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HomeMy WebLinkAboutTIR-4045Job No: 1166-001-005 JESSIE GLEN Technical Information Report L05Sf(054- Prepared For: JPS Holdings, LLC 18124 Riviera Place SW SeatUe, WA 98166 Prepared By: ESM Consulting Engineers, LLC. 33915 1 st Way South, Suite 200 Federal Way, Washington 98003 253) 838-6113 Revised -April 2006 JESSIE GLEN Technical Information Report Revised -April 2006 Prepared for JPS Holdings. LLC 18124 Riviera Place SW Seattle. WA 98166 206) 799-3051 Prepared by ESM Consulting Engineers. LLC 33915 1st Way South. Suite 200 Federal Way. WA 98003 253.838.6113 tel 253.838.7104 fax www.esmcivil.com Job No: 1166-001-005 JESSIE GLEN Technlcallnfonnation Report Prepared For: JPS Holdings, LLC 18124 Riviera Place SW Seattle, WA 98166 20 ... Z -3051 Prepared By: ESM Consulting Engineers, LLC. 33915 1 st Way South, Suite 200 Federal Way, Washington 98003 253) 838-6113 Revised -April 2006 Section 1.0 Section 2.0 Section 3.0 Section 4.0 Part A Part B Part C Part D Part E Section 5.0 Section 6.0 Section 7.0 Section 8.0 Part A Part B Section 9.0 Section 1 0.0 Appendix A AppendixB AppendixC Table of Contents Project Overview Rgure 1 -T1R Worksheet Rgure 2 -Site Location Map Rgure 3 -Drainage Basin, Sub-basins, and Site Characteristics Conditions and Requirements Summary Off-Site Analysis Flow Control and Water Quality Facility Analysis and Design Existing Site Hydrology Developed Site Hydrology Performance Standards Row Control System Water Quality System Conveyance Systems Analysis and Design Special Reports and Studies Other Permits CSWPPP Analysis and Design ESC Plan Analysis and Design SWPPS Plan Design Bond Quantities, Facility Summaries and Declaration of Covenant Operations and Maintenance Manual Stormwater Flow Control Calculations Storm water Quality Calculations Stormwater Conveyance Calculations Project Overview The proposed Jessie Glen project has an area of 7.70 acres and is located in unincorporated King County, on the East Hill of Kent More specifically, as shown in Fi~ure 2 -Site Location, the project is located between 116th Avenue SE and 120t Avenue SE, just north of SE 192nd Street including King County Tax Parcel Numbers 619840-0080, 619840-0100,619840-0120,619840-0140, and 619840- 0320. The property is partially undeveloped, consisting of low density single family residential development All building structures and associated utilities on the project site will be demolished and removed except one manufactured home which will be relocated to Lot 32. The existing 12 inch diameter culvert along 120th Avenue SE will be removed and replaced. According to the Soil Survey of the Pierce County Area issued February 1979, as provided by the United States Department of Agriculture (USDA) Soil Conservation Service, the type of soils located on the Jessie Glen project site are predominantly Alderwood series (AgB). The project site is fairly level with mild site slopes ranging from 1 to 4 percent The proposed development is composed of 49 residential single family lots and the respective roadways and utilities. The single family homes will have a footprint of approximately 1,800 square feet with an additional 544 square feet for the driveway, patios, and walkways for a total of 2,344 square feet of impervious area per lot The total impervious area for the developed lots of 2.64 acres over a total lot area of 6.57 acres results in an average of 40 percent impervious area which is significantly less than the allowed 70 percent Section 5.2 of the 2005 King County Surface Water Design Manual (KCSWDM) has flow control BMP requirements that allow for a reduced impervious surface credit This credit will be applied to the proposed development due to the reduced impervious area per lot The layout of the Jessie Glen project is divided in two separate areas to be developed. These areas are connected via a 30' wide parcel of land, which is proposed to be part of a park area \Tract B). See attached Figure 3 -Drainage Basins, Subbasins, and Site Characteristics for more detail. The natural stormwater runoff from the site sheet flows from the west to the east toward 120th Avenue SE. An undeveloped forested 2.94 acre area upstream of the project site drains to the south portion of the proposed development The proposed stormwater drainage system has been designed to incorporate the undeveloped flows from this property. Storm water drainage for the north and south proposed developed areas includes lawn, foof, and driveway areas from the residential lots as well as asphalt concrete pavement from the proposed roadways. This runoff will be collected in catch basins and conveyed to a combined wetpond and detention stormwater facility. The overflow above the 100 year storm event will be released from the detention facility and conveyed along the east side of 120th Avenue SE south under the existing drainage ditch to an existing catch basin at the intersection with 192nd Street The existing drainage ditch will be restored after construction to original conditions. The existing catch basin is old as shown in Photo 3 of the Level 1 Downstream Analysis and it will therefore be replaced with a new Type 248-inch diameter catch basin (#32). From this location, the Jessie Glen storrnwater drainage will continue to flow off site through a tight-line system then a drainage swale and finally to Big Soos Creek FIGURE 1 -TlR WORKSHEET w <' 8 ~ a ON ., ri:~ ~~ i:i FIGURE 2 SITE LOCATION SE 186TH ST SE 188TH ST SE 189TH IN SE SE 192ND ST SE 196TH ST VICINITY MAP NOT TO SCALE CONSULTING ENGINEERS LLe 33915 1st Way South Federal Way, WA 98003 www.esmcivil.com FtDEJIAL WAf 1'''1 fI38-61U BOTHELL ~2~ (1 ~-~ I H CLE Ei.U~ 5Qg B7~_,gO"" JOB NO. DRAWING NAME DATE: DRAWN Civil Engineering Land Surveying Land Plonning SHEET OF n 1166-001-005 EN-OJ 2005-09-13 EAP Qj 0 Public Works Project ~on0gement Landscape Architecture ~~L-~~~~~ ____ L-~~~~~~~ __ ~~~~~~~==~~ ________________________________________________________ ~ KING COUNTY, WASHINGTON, SURFACE WATER DESIGN MANUAL TECHNICAL INFORMATION REPORT (TIR) WORKSHEET Part 1 PROJECT OWNER AND PROJECT ENGINEER Project Owner JPS Holdings. LLC Phone 206-799-3051 Address 18124 Riviera Place SW Seattle. WA 98166 Project Engineer Laura G. Cociasu Company ESM Consulting Engineers. LLC Phone 253-838-6113 Part 3 TYPE OF PERMIT APPLICATION gf Land Use Services (circle one) Formal SUbdiviSiO~J Short Subdivision / UPD o Building Services (circle one) Multi Family / Commercial / Single Family Residence Clearing and Grading o Right-of-Way Use o Other Part 5 PLAN AND REPORT INFORMATION Technical Information Report Type of Drainage Review cE!ill) Targeted / Large circle one): Site Date (include revision October 2005 dates): Date of Final: 2005 Surface Water Design Manual 1 Part 2 PROJECT LOCATION AND DESCRIPTION Project Name _J"'e""s"'s"'ie'-'G"'I""en"-_______ _ ODES Permit # ____________ _ Location Township ---=:23"-'-'N"'0"'rth"-______ _ Range 5 East Section _3"'3"-________ _ Site Address _____________ _ Part 4 OTHER REVIEWS AND PERMITS o DFWHPA o COE404 o DOE Dam Safety o FEMA Floodplain o COE Wetlands o Shoreline Management o Structural Rockery / Vault / o ESA Section 7 o Other ____ _ Site Improvement Plan (Engineering Plans) Type (circle one): <6!jj) Mod ified / Small Site Date (include revision October 2005 dates): Date of Final: 1/1/05 KING COUNTY, WASHINGTON, SURFACE WATER DESIGN MANUAL TECHNICAL INFORMATION REPORT (TIR) WORKSHEET Rirt 6ADJO~TMEOh[t~Re?M~E§'[i,L:< i" Type (circle one): ~tandariiJ 1 Complex 1 Pre-application 1 Experimental/Blanket Description: (include conditions in TIR Section 2) Request for Adjustment to the Surface Water Design Manual Core Requirement No.1 Date of Approval: Approved September 22. 2005 Monitoring Required (circle one): Yes 18 Describe: ______________________________ __ Start Date: ____________________________________________________________________ __ Completion Date: Community Plan: ---'K"'i"'n""g-'C"o"'u,C!nt"y ________________________________________________________ _ Special District Overlays: ____________________________________________________________ _ Drainage Basin: __ S"'o"'o"'s"'C"""re",e"'k ________________________________________________________ _ Stormwater Requirements: Level 2 Analysis DRiver/Stream 0 Steep Slope ________________________ _ o Lake 0 Erosion Hazard ________________________ _ o Wetlands 0 Landslide Hazard ______________________ _ o Closed Depression 0 Coal Mine Hazard ______________________ _ o Floodplain 0 Seismic Hazard ________________________ _ o Other 0 Habitat Protection 2005 Surface Water Design Manual 111105 2 KING COUNTY, WASHINGTON, SURFACE WATER DESIGN MANUAL TECHNICAL INFORMATION REPORT (TIR) WORKSHEET Soil Type AgB Slopes less than 4% Erosion Potential minimal o High Groundwater Table (within 5 feet) o Sole Source Aquifer o Other o Seeps/Springs o Additional Sheets Attached REFERENCE LIMITATION / SITE CONSTRAINT o Core 2 -Offsite Analysis ________ _ o Sensitive/Critical Areas ________ _ DSEPA ________________________ __ o Other _____________ _ o o Additional Sheets Attached c:" .:_.!.£ .. • •. •. Part 12 TIR SUMMARY: SHEET (provide one TIR Summary Sheet per Threshold Discharge Area) . • .: ,'. .' .... :. ". ... ..:. . .' '.: .. : : .... Threshold Discharge Area (name or description): Jessie Glen Drainage Basin Core Requirements (all 8 apply) Discharge at Natural Location Number of Natural Discharge Locations: 1 w/ Adjustment Offsite Analysis Level: G) / 2 / 3 dated: March 4, 2005 Flow Control (include facility summary sheet) Level: 1 / ® / 3 or Exemption Number ____ _ Small Site BMPs Conveyance System Spill containment located at: Lowest Catch Basin 2005 Surface Water Design Manual 1/1105 3 KING COUNTY, WASHINGTON, SURFACE WATER DESIGN MANUAL TECHNICAL INFORMATION REPORT (TIR) WORKSHEET Core Requirements (continued) Erosion and Sediment Control ESC Site Supervisor: Contact Phone: After Hours Phone: Maintenance and Operation Responsibility: Private I(fUbliSJ If Private, Maintenance Log Required: Yes 1 No Financial Guarantees and Liability Provided: Yes G Water Quality (include facility summary sheet) Type: 91 Sensitive Lake 1 Enhanced Basic 1 Bog or Exemption No_ Landscape Management Plan: Yes 1 No Special Requirements (as applicable) Area Specific Drainage Requirements Type: C~O 1 MDP 1 BP 1 LMP 1 Shared Facility lone Name: Floodplain/Floodway Delineation Type: Major 1 Minor 1 Exemption 1 ~ 100-year Base Flood Elevation (or range): Datum: Flood Protection Facilities Describe: Source Control (commercial 1 industrial land use) Describe landuse: Describe any structural controls: Oil Control High-use Site: Yes 18 Treatment BMP: Maintenance Agreement: Yes 1 No with whom? 2005 Surface Water Design Manual 1/1/05 4 KING COUNTY, WASHINGTON, SURFACE WATER DESIGN MANUAL TECHNICAL INFORMATION REPORT (TIR) WORKSHEET Other Drainage Structures Describe: _________________________________ _ MINIMUM ESC REQUIREMENTS DURING CONSTRUCTION Clearing Limits D Cover Measures D Perimeter Protection D Traffic Area Stabilization Sediment Retention Dust Control Construction Sequence Flow Control Detention o Infiltration o Regional Facility o Shared Facility o Small Site BMPs o Other Type/Description Combined Wetpond and Detention Facility 2005 Surface Water Design Manual 5 MINIMUM ESC REQUIREMENTS AFTER CONSTRUCTION a" Stabilize Exposed Surfaces mRemove and Restore Temporary ESC Facilities Clean and Remove All Silt and Debris Ensure Operation of Permanent Facilities D Flag Limits of SAO and open space preservation areas o Other _____________ _ Water Quality D Biofiltration Wetpool D Media Filtration D Oil Control D Spill Control D Small Site BMPs D Other TypelDescription Combined Wetpond and Detention Facility 1/1/05 KING COUNTY, WASHINGTON, SURFACE WATER DESIGN MANUAL TECHNICAL INFORMATION REPORT (TIR) WORKSHEET o Drainage Easement o Access Easement o Native Growth Protection Covenant o Tract Other -Temporary Construction/Grading Easement 2005 Surface Water Design Manual 6 o Cast in Place Vault o Retaining Wall o Rockery> 4' High o Structural on Steep Slope o Other 1/1/05 Conditions and Requirements Summary Review of Eiqht Core Requirements and Five Special Requirements The proposed project has been reviewed in accordance with the Core and Special Requirements in Sections 1.2 and 1.3 of the 2005 King County Surface Water Design Manual (KCSWDM) for a full drainage review of the proposed Jessie Glen development The conclusions determined by evaluating the Eight Core Requirements and Rve Special Requirements area as follows: Core Requirement No. 1 -Discharge at the Natural Location Discharge of stormwater flows and surface water runoff from the site flows to two natural locations. The proposed storm drainage system improvements will discharge flows to one of the two natural drainage locations using an adjustment An adjustment to the Core Requirement #1 has been requested to combine the subbasins for the north and south sites into one post developed stormwater drainage facility along 120th Avenue SE. The adjustment request was approved September 22, 2005. Core Requirement No.2 -Offsite Analvsis An offsite analysis is provided in Section 3 to evaluate downstream conditions. This Level 1 Downstream Analysis was originally submitted to King County on March 4, 2005. Core Requirement No.3 -Flow Control The project site is located in the Conservation Flow Control Areas. Per 2005 KCSWDM, historic site conditions apply with a Level 2 flow control side matching historic durations for 50% of the 2 year through 50 year peaks and matching the historic 2 year and 10 year peaks. The exemptions to this core requirement do not apply to the proposed project Row-control will be provided by means of a detention pond designed to the Level 2 flow control requirements. For more information and calculations, see Section 4.0, Part D. Core Requirement No.4 -Conveyance System Conveyance reqUirements for a new system are described in Section 1.2.4 of the 2005 KCSWDM. The conveyance system for the proposed development will have sufficient capacity to convey and contain the 25-year storm peak flow. As prescribed in Table 3.2 of the 2005 KCSWDM, due to tributary areas to individual conveyance elements being less than 10 acres, the peak flow for the conveyance system was sized using the Rational Method. See Section 5.0 of this report for more information and calculations. Core Requirement No.5 Erosion and Sediment Control The proposed project includes clearing and grading for the roadways and the proposed park shown in Tract B. Erosion and sediment controls will be provided to prevent, to the maximum extent possible, the transport of sediment from the project site to downstream drainage facilities, water resources, and adjacent properties. The proposed erosion and sedimentation control measures are further described in Section 8.0 of this report in accordance with criteria in Section 1.2.5 and Appendix D of the 2005 KCSWDM. Core Requirement No. 6 Maintenance and Operations Maintenance and operation of the drainage facilities on residential lots will be the responsibility of the property owner. Maintenance and operation of the drainage facilities within public right-of-way and the combined wetpond and detention stormwater facility will be the responsibility of King County. The Maintenance and Operation Manual for the stormwater system is included in Section 10.0 of this report. Core Requirement No. 7 Financial Guarantees and Liability All drainage facilities constructed or modified for projects (except downspout infiltration and dispersion systems) must comply with the financial guarantee requirements as provided in the King County Bond Quantities Worksheet This information is further described in Section 10.0 of this report. Core Requirement NO.8 Water Quality All proposed projects must provide water quality (WQ) facilities to treat the runoff from new and/or replace pollution-generating impervious surfaces and pollution- generating pervious surfaces. As identified on the King County Water Quality Treatment Areas Map, the site is considered a Basic Water Quality. Due to site constraints, the proposed development will utilize a wetpond to treat for water quality control. The exemptions to this core requirement do not apply to the proposed project. For more information, see Section 4.0, Part E. The following Special Requirements do not apply to the proposed project: Special Requirement No.1 -Other Adopted Area -Specific Requirements Special Requirement No.2 -Roodplain/Roodway Delineation Special Requirement NO.3 -Rood Protection Facilities Special Requirement No.4 -Source Controls Special Requirement NO.5 -Oil Control ma mCON SilL TIN G E N 6 NEE R S I Ie I @J I ® I ({I I Janual)' 24, 2005 Job No. 1166-001-005 Mr. Ted Cooper, P.E. King County DDES Land Use Services Division 900 Oaksdale Avenue SW Renton WA 98055-1219 Re: Jessie Glen Application No. L05PO005 Dear Mr. Cooper: On November 3, 2005 Pete Dye sent Mr. Joe Singh at JPS Holdings, LLC. a letter regarding the Penn it Fee Estimate for the proposed Jessie Glen development As you know, Mr. Singh has already provided a check for $17,000 to the County. Included in this letter was a request for additional infonnation. The requested additional infonnation is listed below in items N through G) with our responses in bold. N Illumination Plans required per KCRS 5.05 Illumination Plans are currently being designed by Puget Sound Energy and will be submitted as soon as the design is completed. B) Pavement design for arterials per KCRS 4.03 The pavement design for 116th Avenue SE arterial will be included in the second submittal of the construction plan set that will incorporate the King County DDES comments. C) TlR Section 1 -SummaI)' and/or analysis of BMP's (Drainage Manual Chapter 5.2) The requested summary and/or analysis will be included in the second submittal of the Technical Information Report that will incorporate the King County DDES comments. D) TlR Section 2 -Plat conditions with applicant responses On behalf of JPS Holdings, LLC., ESM Consulting Engineers, LLC. is submitting with this letter our responses to the conditions for final plat approval in the Hearing Examiner's Report and Decision dated October 20, 2005 for the preliminary plat of Jessie Glen, application number L05PO005. The original conditions are shown in italics with our responses in bold. E) TlR Section 4 -Evaluation of enhanced water quality (Drainage Manual Page 1-60) The enhanced water quality standard is required for development that exceeds 8 units per acre when considering lot area only. The proposed Jessie Glen development has 49 lots in 6.57 acres lot area Therefore, the proposed development with 7.46 units per acre will not require an enhanced water quality standard. 720 south 34Bth Street FedlHal Way, WI<. 99003 Tel (253) 8JB 6113 Fax (253) B38 7104 WWW.esmcivit.com Bolhet\ (425) "5 6141, Toll Free (800) 3455694 Civil Engineering Project Management L2nd Surveying Land Pl",nning Public Works. Landscape Architecture Mr. Ted Cooper, P.E. January 24, 2006 Page 2 F) . TlR Section 7 -Pollution plan (Drainage Manual pg. 2-28) Attached is the Stormwater Pollution Prevention Plan (SWPPP) for the proposed Jessie Glen project that is referenced in Section 7 of the Technical Information Report G) TlR Section 9 -Bond quantity sheets The requested bond quantity sheets will be included in the second submittal of the Technical Information Report that will incorporate the King County DOES comments. RESPONSES TO CONDmONS FOR FINAL PLAT APPROVAL IN THE HEARING EXAMINER'S REPORT AND DECISION DATED OCTOBER 20. 2005 FOR THE PREUMINARY PLAT OF JESSIE GLEN. APPUCATlON NUMBER L05POOO5 1. Compliance with all platting provisions of Title 19 of the King County Code. This condition will be met 2. All persons having an ownership interest in the subject property shall sign on the face of the final plat a dedication which includes the language set forth in King County Council Motion No. 5952. This condition will be met 3. The plat shall comply with the base density (and minimum density) requirements of the R-6-S0 zone classification. All lots shall meet the minimum dimensional requirements of the R-6-S0 zone classification or shall be as shown on the face of the approved preliminary plat whichever is larger, except that minor revisions to the plat which do not result in substantial changes may be approved at the discretion of the Department of Development and Environmental Services. This condition will be met 4. All construction and upgrading of public and private roads shall be done in accordance with the King County Road Standards established and adopted by Ordinance No. 11187, as amended (1993 KCRS). This condition will be met 5. The applicant shall obtain documentation by the King County Rre Protection Engineer certifying compliance with the fire flow standards of Chapter 17.08 of the King County Code. The documentation shall be obtained. 6. . Rnal plat approval shall require full compliance with the drainage provisions set forth in King County Code 9.04. Compliance may result in reducing the number andlor location of lots as shown on the preliminary approved plat Preliminary review has identified the following conditions of approval which represent Mr. Ted Cooper, P.E. January 24, 2006 Page 3 portions of the drainage requirements. All other applicable requirements in KCC 9.04 and the Surface Water Design Manual (SWDM) must also be satisfied during engineering and final review. This comment has been noted. a Drainage plans and analysis shall comply with the 2005 King County Surface Water Design Manual and applicable updates adopted by King County. DOES approval of the drainage and roadway plans is required prior to any construction. This comment has been noted. b. Current standard plan notes and ESC notes, as established by DOES Engineering Review, shall be shown on the engineering plans. This condition will be met c. The following note shall be shown on the final recorded plat All building downspouts, footing drains, and drains from all impeNious surfaces such as patios and driveways shall be connected to the permanent storm drain outlet as shown on the approved construction drawings # on file with DOES and/or the King County Department of Transportation. This plan shall be submitted with the application of any building permit All connections of the drains must be constructed and approved prior to the final building inspection approval. For those lots that are designated for individual lot infiltration systems, the systems shall be constructed at the time of the building permit and shall comply with plans on file .• This completed note shall be shown on the final recorded plat 7. The drainage detention facility shall be designed to meet at a minimum the ConseNation Row Control and Basic Water Quality provisions in the 2005 King County Surface Water Design Manual (KCSWDM). This condition has been met 8. A drainage adjustment (L05V0052) is approved to combine the onsite subbasins into one post-developed detention facility. All conditions of approval for this adjustment shall be incorporated into the engineering plans . The conditions of approval for this adjustment have been incorporated into the engineering plans as requested. 9. The proposed subdivision shall comply with the 1993 King County Road Standards (KCRS) including the following requirements: Mr. Ted Cooper, P.E. January 24, 2006 Page 4 This condition will be met a Road A from 12cJ1' Avenue SE to Lot 37 shall be improved to the urban one-half street standard. The remaining portion of Road A from Lot 37 to the south plat boundary shall be improved to the urban subaccess street standard. This condition will be met Road A shall include an adequate pavement radius to 12cJ1' Avenue SE on the north side; unless otherwise approved by DOES. Property owner permission and an appropriate easement are required for this improvement to be submitted with the engineering plans. The existing private driveway at this location is to be abandoned, with new access to Parcel 6198400300 on the new Road A Property owner permission is required to relocate the driveway. Note that DOES has received a letter of intent to provide permission. This condition will be met This subdivision shall comply with Section 1.03(0) of the KCRS. This Section requires a continuous public access prior to recording. If the proposed subdivision to the south (L04S0003) is not completed and approved by King County prior to this subdivision recording, a temporary turnaround shall be provided at or near the south end of Road A, subject to DOES approval as to location. This condition will be met b. Roads B, C, and 0 shall be improved to the urban subaccess street standard. This condition will be met c. The west RIW line for Road A shall be extended north across Lot 36 and Tract C to the north line of Tract C. This condition will be met d. The east RIW line for Road C shall be extended north across Lot 7 and 8 to the north line of Lot 7. This condition will be met e. FRONTAGE: The frontage of the site along 116"' Avenue SE shall be improved to the urban minor arterial standard (33 ft half-width pavement section). The design shall require compliance with Section 4.01 (f) of the KCRS; asphalt overlay when widening. Mr. Ted Cooper, PE January 24, 2006 Page 5 This condition will be met f. Twelve feet of additional RIW is required to be dedicated along the 11 ffh Ave SE frontage as required for a 42 ft total half width RIW(east side). This condition will be met g. FRONTAGE: The frontage along 120th Ave SE (west side) shall be improved at a minimum to the urban neighborhood collector standard. The design shall require compliance with Section 4.01 (f) of the KCRS; asphalt overlay when widening. This condition will be met h. Tract A shall be a minimum 26 feet wide and improved as a private access tract per Section 2.09 of the KCRS. This tract shall be owned and maintained by the lot owners served. Notes to this effect shall be shown on the engineering plans and on the final plat map. As an altemative to private access tract status, Tract A may be improved and dedicated as a public road subject to the KCRS. This condition will be met i. Tract C shall be a minimum 20 feet wide and improved as joint use driveways per Section 3.01 of the KCRS. This tract shall be owned and maintained by the lot owners served. Notes to this effect shall be shown on the engineering plans and on the final plat map. This condition will be met j. A minimum 5 foot wide paved, public pedestrian walkway shall be provided between Road A and Road B, through Tract B. This condition will be met k Modifications to the above road conditions may be considered according to the variance provisions in Section 1.08 of the KCRS. This condition will be met 10. All utilities within proposed rights-of-way must be included within a franchise approved by the King County Council prior to final plat recording. This comment has been noted. 11. The applicant or subsequent owner shall comply with King County Code 14.75, Mitigation Payment System (MPS), by paying the required MPS fee and administration fee as determined by the applicable fee ordinance. The applicant Mr. Ted Cooper, P.E January 24, 2006 Page 6 has the option to either: (1) pay the MPS fee at final plat recording, or (2) pay the MPS fee at the time of building permit issuance. "the first option is chosen, the fee paid shall be the fee in effect at the time of plat application and a note shall be placed on the face of the plat that reads, 'All fees required by King County Code 14.75, Mitigation Payment System (MPS), have been paid.' If the second option is chosen, the fee paid shall be the amount in effect as of the date of building permit application. This comment has been noted. 12. Lots within this subdivision are subject to King County Code 21 A 43, which imposes impact fees to fund school system improvements needed to seNe new development As a condition of final approval, fifty percent (50%) of the impact fees due for the plat shall be assessed and collected immediately prior to recording, using the fee schedules in effect when the plat receives final approval. The balance of the assessed fee shall be allocated evenly to the dwelling units in the plat and shall be collected prior to building permit issuance. This condition will be met 13. There shall be no direct vehicular access to or from 116th Avenue SE from those lots which abut it A note to this effect shall appear on the engineering plans and final plat This condition will be met 14. The planter islands (if any) within the cul-de-sacs shall be maintained by the abutting lot owners or homeowners association. This shall be stated on the face of the final plat This condition will be met 15. Prior to final plat approval and recording, the applicant shall provide a valid Transfer of Development Rights (TOR) Certificate approved by the King County Department of Natural Resources to create the three additional lots within the proposed development The certificate must show the applicant (or successor or assign) as the lawful owner of the development rights. This condition will be met 16. . Suitable recreation space shall be provided consistent with the requirements of KCC 21 A 14.180 and KCC 21 A 14.190 (i.e., sport courtfsl, children's play equipment, picnic tab/e[sj, benches, etc.). This condition will be met a A detailed recreation space plan (i.e., area calculations, dimensions, landscape specifications, equipment specifications, etc.) shall be Mr. Ted C90per, P.E. January 24, 2006 Page? submitted for review and approval by DOES and King County Parks prior to or concurrent with the submittal of the engineering plan. This plan must not conflict with the Significant Tree Inventory & Mitigation Plan. This condition has been mel b. A performance bond for recreation space improvements shall be posted prior to recording of the plat This condition will be mel 17. A homeowners' association or other workable organization shall be established to the satisfaction of DOES which provides for the ownership and continued maintenance of the recreation, open space and/or sensitive area tract(s). This condition will be mel 18. Street trees shall be provided as follows (per KCRS 5.03 and KCG 21 A 16.050): a Trees shall be planted at a rate of one tree for every 40 feet of frontage along all roads. Spacing may be modified to accommodate sight distance requirements for driveways and intersections. This condition will be mel b. Trees shall be located within the street right-of-way and planted in accordance with Drawing No. 5-009 of the 1993 /(jng County Road Standards, unless King County Department of Transportation determines that trees should not be located in the street right-of-way. This condition will be mel c. If /(jng County determines that the required street trees should not be located within the right-of-way, they shall be located no more than 20 feet from the street right-of-way line. This condition will be mel d. The trees shall be owned and maintained by the abutting lot owners or the homeowners association or other workable organization unless the County has adopted a maintenance program. Ownership and maintenance shall be noted on the face of the final recorded plat This condition will be mel e. The species of trees shall be approved by DOES if located within the right-of-way, and shall not include poplar, cottonwood, soft maples, gum, any fruit-bearing trees, or any other tree or shrub whose roots are likely to Mr. Ted Cooper, PoE January 24, 2006 Page 8 obstruct sanitary or storm sewers, or that is not compatible with overhead utility lines. This condition will be met t The applicant shall submit a street tree plan and bond quantity sheet for review and approval by DOES prior to engineering plan approval g. This condition will be met The applicant shall contact Metro Service Planning at 684-1622 to determine if 116'" Avenue SE andlor 12d" Avenue SE are on a bus route. If 116t" Avenue SE andlor 12dh Avenue SE are a bus route, the street tree plan shall also be reviewed by Metro. Metro Service Planning has been contacted and 116th Avenue SE and 120111 Avenue SE are not on a bus route. h. The street trees must be installed and inspected, or a performance bond posted prior to recording of the plat If a performance bond is posted, the street trees must be installed and inspected within one year of recording of the plat At the time of inspection, if the trees are found to be installed per the approved plan, a maintenance bond must be submitted or the performance bond replaced with a maintenance bond, and held for one year. After one year, the maintenance bond may be released after DOES has completed a second inspection and determined that the trees have been kept healthy and thriving. This condition will be met i. A landscape inspection fee shall also be submitted prior to plat recording. The inspection fee is subject to change based on the current County fees. This condition will be met 19. To implement KCC 21.A38.230, Special District Overlay -significant trees, which applies to the site, a detailed tree retention plan shall be submitted with the engineering plans for the subject plat The tree retention and engineering plans shall be consistent with the requirements of KCG. No clearing of the site is permitted until the tree retention plan is approved by DOES. Ragging and temporary fencing of trees to be retained shall be provided, consistent with KCG. The placement of impervious surfaces, fill material, excavation work, or the storage of construction materials is prohibited with the fenced areas around preserved trees, except as may be permitted under the provisions of KCG. A note shall be placed on the final plat indicating that the trees shown to be retained on the tree retention plan shall be maintained by the future owners of Mr. Ted Cooper, P.E. Januaiy 24, 2006 Page 9 the proposed lots, consistent with KGG 21 A38.230B6. The tree retention plan shall be included as part of the final engineering plans for the subject plat This condition will be met If you have any questions during your review of this submittal, please call me at (253) 838- 6113. Sincerely, ESM CONSULTING ENGINEERS, LLC. 0~ LAURA G. COCIASU, P.E Project Engineer Attachments: Stormwater Pollution Prevention Plan (1 copy) cc: Joe Singh, JPS Holdings LLC. (letter only) esmBlengnesm-jobsl11661001 lOOSldocument\letter-OOS.doc 3 Off-site Analysis The attached Level 1 Downstream Analysis evaluates the drainage system Y. mile downstream of the site along with the five tasks outlined under the Level 1 Downstream Analysis. JESSIE GLEN PRELIMINARY PLAT LEVEL ONE DOWNSTREAM ANALYSIS MARCH 4. 2005 JOB NO: 1123-002-004 Prepared for The Herbrand Company ATTN: Ty Pendergraft 315 39 th Ave. SW. Suite 8 Puyallup. WA 98373 253.848.7700 Submitted by ESM Consulting Engineers. LLC 720 South 348'· St. FederalVVay. VVA 98003 253.838.6113 tel 253.838.7104 fax www.esmcivil.com March 4, 2005 Approved By: King County LEVEL ONE DOWNSTREAM ANALYSIS FOR Jessie Glen Preliminary Plat Prepared for: The Herbrand Company 315 39th Ave. SW, Suite 8 PUYALLU~WA 98373 Prepared by: ESM Consulting Engineers 720 So. 348111 Street FederalWa~WA 98003 Job No. 1123-002-004 Date TABLE OF CONTENTS Task 1 Task 2 Task 3 Task 4 Task 5 Study Area Definition and Maps............................................................................ 1 Resource Review ............... _.................................................................................................. 2 Reid Inspection .............................................................. _........................................................ 3 Drainage System Description and Problems Descriptions..... 4 Mitigation of Existing or Potential Problems ............................................ 5 Figures Offsite Analysis Topo Map............................................................................................................................................ Back Pocket Appendix A - Appendix B - Appendix C - Appendix 0 - Appendix E - Appendix F - Appendix G - Vicinity Map FEMAMap Soils Map Appendices Offsite Analysis System Table, Offsite Analysis Photps Drainage Complaints Aerial Photos, Water Quality/Flow Control Map Preliminary Detention Pond Calculations, Preliminary Water Quality Pond Calculations Task 1. Study Area Definition and Maps The Jessie Glen Preliminary Plat is a proposal to subdivide a 7.7 acre parcel into 48 single-family residences. The project is located in unincorporated King County, on the east hill of Kent The project is more specifically located between 116th Avenue SE and 120th Avenue SE, just north of SE 192nd Street and includes King County Tax Parcel Numbers 6198400-0080, 619840-0100, 619840-0120, 619840-0140, and 619840- 0320. Please see Appendix A for vicinity map. This property is partially undeveloped and also contains a few existing residential homes. This property is generally surrounded by lower density single-family residential development; however, there are a few similar, higher density projects in various stages of development in the immediate vicinity. The runoff from the site currently sheet flows from the west to the east toward 120th Avenue S.E. Approximately 2.9 acres of area drains to the site from the west The project is located within the Soos Creek drainage basin. The drainage study area is approximately one quarter mile long path encompassing the site's downstream corridor. See the exhibit in rear pocket of th'ls report for a topographic map of the site and a map of the basin study area. Task 2. Resource Review The following resources have been reviewed for the downstream analysis: Adopted Basin Plans The site is located within the Soos Creek Basin. Roodplain/floodway (FEMA) Maps There is no mapped floodplain in this area per the available FEMA Maps. The site is located in Zone X per the Rood Insurance Rate Map (RRM) map number 53033C0991 F. A copy of the RRM map is included in Appendix B of this report Sensitive Areas Folio Wetlands -None mapped. Streams and 100-Year Roodplains -None mapped Erosion Hazard Areas -None mapped. Landslide Hazard Areas -None mapped Seismic Hazard Areas -None mapped Coal Mine Hazard Areas -None mapped. DNRP Drainage Complaints Drainage complaints are located in Appendix E of this report U. S. Department of Agriculture, King County Soils Survey The soils are predominantly of the Alderwood series (AgB). A copy of the King County Soils Survey map is included in Appendix C of this report Wetlands Inventory Map There are no wetlands located on this site. Erosion Hazard and Landslide Hazard Area Map The site is not located in a erosion or landslide hazard area Row Control Applications Map The site is located in a Conservation Row Control area per the 2005 King County Surface Water Design Manual Water Quality Applications Map The site is located in the Basic Water Quality treatment area per the 2005 King County Surface Water Design Manual. 2 Task 3. Field Inspection A site reconnaissance was performed on February 16, 2005 for the purpose of analyzing the proposed project site and its upstream and downstream corridors. The offsite drainage system was inspected'!. mile downstream. These ten items were inspected during the field inspection per the 2005 King County Surface Water Design Manual. 1. Investigate any problems reported or observed during the resource review. The culvert that was plugged in drainage complaint 96-1550 appears to be plugged again. 2. Locate all existing /potential problems constrictions or lack of capacity in the existing drainage system. The existing drainage system appears to have adequate capacity. 3. Identify all existing/potential downstream drainage problems as defined in section 1 .2.2.1. The drainage complaints are included in Appendix E of this report Drainage complaints 1991-1132 and 1997-1301 were missing and not available. 4. Identify all existing/potential overtopping, scouring, band sloughing, or sedimentation. None observed. 5. Identify significant destruction of aquatic habitat or organisms (e.g., severe siltation, bank erosion, or incision in a stream). None observed. 6. Collect qualitative data features such as land use, impervious surfaces, topography, and soil types. This information is included in Task 4 of this report 7. Collect information on pipe sizes, channel characteristics, drainage structures, and relevant critical areas (e.g., wetlands, streams, steep slopes). This information is included in Task 4 of this report 8. Verify tributary basins delineated in Task 1. The tributary basins were verified. 9. Contact neighboring property owners or residents in the area about past or existing drainage problems, and describe these in the report (optional). No property owners were contacted 10. Note the date and weather conditions a the time of the inspection. The site visit was conducted on February 16, 2005. The weather conditions were dry, 50 degrees Fahrenheit and clear and sunny. 3 Task 4. Drainage System Description and Problem Descriptions Please see Appendix 0 for downstream photos and off-site analysis drainage system table. The site currently drains from the west to the east The northwest 4.3 acres drains toward the adjacent property to the east The southeast 3.5 acres drain toward the drainage ditch located along 120th Avenue S.E. This area also receives runoff from approximately 2.9 acres to the west Surface water runoff that leaves the site enters a ditch along the west side of 120th Avenue S.E. It flows to the south to the intersection of SE 192nd Street and 120th Avenue S.E. There it enters a 12" storm drainage pipe and flows to a catch basin in 120th Avenue S.E. The runoff then flows to the east through 18" storm pipe at approximately 4% slope. The road continues down the hill and the pipes slopes increase to approximately 10%. The pipe size increases to 24" and the flow discharges to a half concrete pipe. The flow continues through a heavily vegetated swale toward a driveway. It appears that the runoff is supposed to flow through a concrete culvert This culvert is plugged and the runoff appears to be infiltrating in the ground. There is evidence that water has been flowed across the driveway and caused some erosion. One problem observed during the site visit was the ditch along the north side of 120th Avenue S.E. had some debris in it This is a minor problem and the ditch could be cleaned out easily to allow for better flow. The other problem observed was the plugged pipe that caused erosion across the driveway. This appears to have been a problem before and was mentioned in drainage complaint #96-1550. The offsite drainage complaints from King county are Included in Appendix E. 4 Task 5. Mitigation of Existing or Potential Problems The existing downstream problem that was observed was the erosion of the driveway described in Task 4. The developed site will not aggravate this existing problem because the site will also have Level 2 flow control. This will restrict the flow of the 2-year release to 50% of the pre-developed site. 5 APPENDIX A Vicinity Map 5E 186TH 5T 5E 192ND 5T 5E 196TH 5T SE 189TH LN 5E 190TH LN w iE 0 5E 188TH 5T w I l- e N VICINITY MAP KING COUNlY. WASHINGTON n N.T.S. APPENDIX B FEMAMap 32 w => z ZONE X STREET t;; APPROXIMATE SCALE IN FEET 500 0 500 E3 NATIONAL FLOOD INSURANCE PROGRAM FLOOD INSURANCE RATE MAP KING COUNTY, WASHINGTON AND INCORPORATED AREAS PANEL 991 OF 1725 ISEE MAP INDEX FOR PANELS NOT PRINTED) PANEL sumx KING CDUNTY UNINCO~POIIA.n;o AAEAS 5JQ(I11 O!!el MAP NUMBER 53033C0991 F MAP REVISED: MAY 16,1995 map. changes date on the Rood Insurance APPENDIXC Soils Map APPENDIX D Offsite Analysis Drainage System Table Offsite Analysis Photos Photo 1 Drainage ditch along the north side of 120th Avenue S.E. where pond would discharge. Photo 2 Drainage ditch along 120th Ave SE at the SE 192nd street intersection. The runoff enters the road conveyance system through a 12" inlet pipe. Looking south I Photo 3 Catch basin at 120th Ave SE and SE 192nd Street intersection. Photo 4 Catch basin at 120th Ave SE and SE 192nd Street intersection Lo oking west Catch basin along SE 192nd Street Looking East Photo 5 Catch basin along SE 192nd Street Looking East Photo 6 Catch basin along SE 192nd Street Lo oking East Photo 7 Z Catch basin along SE 192nd Street Looking East Photo 8 Photo 9 24" outlet pipe drains to a half 24" concrete culvert ditch Looking west Photo 10 Half 24" concret e culvert ditch Photo 11 Heavily vegetated drainage swale in front of 19121 124th Ave SE Looking west Photo 12 Plugged inlet of culvert across driveway to house at 19121 124111 Ave SE Looking East Photo 13 Broken outlet of culvert across driveway to house at 19121 124th Ave SE Looking West Photo 14 Eroded ditch across driveway to house at 19121 124th Ave SE Looking East Photo 15 Eroded ditch across driveway to house at 19121 124111 Ave SE Looking East OFF-SITE ANALYSIS DR AGE SYSTEM TABLE Surface 'Vater Desigu Manual, Core Requirements #2 Basin: So os Creek Subbasin Name: Subbasin Nnmber: Reach See Figure 3.1 and Photos A B C D E F G I-I Drainage Component Type, Name & Size Type: s heet flow, swa le, stream, c hannel, pipe. pond; Site: diarncter, surface area DilCh 12 " Pipe Calc h Bas in s and 18 " Pipe Catch Basins and 18" Pipe Drainage Component Description Slope I Distaneeljrom Existing Problems Potential . Observations .of Field Site'Discllarge '. ' ... "'" Problems: : Inspector ResoUrce Reviewer or R es ident Drait.I.<mc basin, vegetation, ·c;onstIjc:tions,."up:~er ,capa~ity, ,,' :~~~ ):riputary,area,. cover, deplh;lypc 'of ··..·ponding·; oVerhJppirlil ;Uoodmg, ". '" 'Iikelihood of·· sensitive area, vo lume h<l,bita~.o(organism destrd6,t.ip#,~,;" ;:::; ,p'io;b,l:~.rri,'~verflqw · scouriflg, bank slo ughinll, :. . '.' pathways; po\ential Grassy, 2' wide at bottom, 2 ' deep (see phOlO #2) F lows soulh F lows eas t Flows cast sedinjen ta~io~, i!tcisjon ~ other ·lPt?~Rts', erosion 2% I 0 -300' I None None None Observed 2% I 300' -320' None None None Observed 4% I 320' -900 ' None None None Observed 10 % I 900' -136 0 ' No n e None None Observed Manhole and 24" Pipe I Flows cast -10 % I 1360'-1400' None None None Observed Half24" concrete pipe I Overgrown with vegetation Swa le Swa le H eavil y vegetaled, 3'-5 wide Flows across driveway. 2' w ide, 6" deep 2% 1400'-1530' 2% 15 30'-1670 ' 2% 16 70' + None None Eroded driveway None None Further erosIOn None Observed None Observed Eroded driveway APPENDIX E Drainage Complaints A04PM288 HYDRO/GEO 9;;i ld Eagle Nests N T(N{flStlp unes Wlldlilo Nelv>«!< CJ BiI $lns 1'-R OSUNES SeCU N ES l\!TW PIJNES IVStrae>s s.t'l._m 1p N,2S I,'V~ b~:~ SAO WeU.md SAO Landslk19 I(! SAO CCQI Mine t::S SAO Seismic g SAO ErosIon W;;I ler Bodies o WlRO Drallla\16 Complain ts I Par!:els Wo'F'W'''''' "'.~, WOFW2 OR TREES1 WDFW2 OR TREES) TREES2 N FEMACross Sectlons Cl FEMA F\oo!t.oray o FEMA tOO-yr . Floodplain O~es NO ly Boundaries 500 1000 Feel I"" 1000 feet King County Plot da 19: Dec 7,2004; \\ddesD0 1I..;.Ol;gls\ilv_oo\l\projocts\b<lse2.ap- FEB, 22. 2005 3: 45PM KING CO, WLRD NO, 0947 KING CoUNTY iillRF:a:CE WATER MANAGEME:NT DMSION DRAINAGE INVESTIGATION REPORT p, 7/19 Paga 1: INVESTlGAnON'REQU,EST Type. c: Data: S. OK'd by; FDe'No. 96-08o~ r . i: "ebeiv~ by: , , ecaivPd from: ' (Pl ..... print plainly fo, ooanntngJ. (Day) (Eve) i V/tL re Y /J.rMIt.7?l&/ PHONE«P~/7Itt -"----;1 ill ~R'~SS: ,bpc S' WJa.ngct&t. b~A!(Clrf ______ State ,Zip,___ ;1 I ~ 'I " lo'catlon of problem. if different: . .' : ' IIrtported Problem: II}fI'A c-r~ §"/re;.dt:'" #ltL '~,&.::oG.. -.. W'iM-r' QN bc? '-reP £ ?I_/,J'J:) <",(eF, r~ j)-b1//./I1 C'o:! '') I . 46 L ! i;, plat name: )lor..fhwesrerr) I ' i Other age:ncies involved: f ~ ImlnOI 5111~' ;!ilO! i ~.u33 2.3 ~ ParCel No. 6/Cf8/fO 631.{ I ii74~--r--R- Basin ?.:?O CounGii Dist q Charge No: lot No: 8 Block No: ..z. No Field Investigation Needed _____ _ KroU 60SuI Th.Bros: New 686 £2..3 Old <1211:;;" i8~, RESPONSE: Cltlzen notified on f=t., 'Ie. by _ phone -+ letter _In person e-c J4-r,'crtc.~ [~1T~ D,SPOSfTlON: Turned 10, __ on ____ by __ _ OR: No further action recommended becau, Lead agency has been notified: Problem has been corrected. --=-·N:;:o:-:p=ro:;:b;:le:::m-;:h~as::-;b~e~en::-;iG'cle::-:nt:;:;ifi::=le7cl.-----=P""'rio-r-;-Inve-sti""'g-atl""o-n-a""dd""re~s-se-s-pr-o'blerr: 0& File '" ' • ; I' , L Private problem -NDAP win 'not consider because: Watr.r originates onshe and/or on neighboring parcel DATE CLOSED: L;:;on; :~r~ S: :JJ? ' _ Other (SpecifY): i1.jF8Ikdli/O~, i I,~ i; l l~ p i 11 I" FEB. 22. 2005 3:45PMI::il/\l l KING CO. WLW'Hl O::l..l..V/y\ "vv'lOIl'" r..J..""V"--.I'NO. 0947 i ," _... .• ----''-_ P. 8/~9 ___ I tI l complaint 95-0805 Wilsey Samlleon Investi~ated by Jacquie ~ittle 03/29/96 1 1180S I l 120l'H AVE @' t I~., 0; fl'C,+w?"-L/- f:'~~we. S"- I a"'" .. elk-!, r Q) N If ~~r "-<.f Ie sr; 19'1n=l L~oK",,!'i nor'U, /U:~ #..t. .1 •. 1 .' IN I4J.trrt..£t' t#.p ~ Ol:::tnJ we..... c::.1at')jI' -h<L 12.?" Cl1'/p I ~" c,.."", F m~ d,ra.J (J f' I d-c.v~ ~ .:>r-: i +-. .....,""'>" I I SE H2ND ST c~ol fo 192 ~<f . . Ic " fEB,22.2005 3:46PM KING CO, WlRD ~O,0947 P,9/19 TO:: FROM: DATE: XING COUN'l'Y sURFACE WATER MANAGEMENT lNT2RNAJ. KEKOlUlNDUM Wil~~Y Hamilton -..AJi1 Larry Gettle f'" April 6, 1996 SUBJECT: Hamilton -96-0805 south 192nd street Drain~ge -spring Hill Element~, Per your request I have investigated the constructed drainage system along Southeast 1.92nd street west of 1.20th Avenue . southeast, reviewed the drainage plans ana field notes ,for Southeast 192nd street and reviewed the drainage impro'VelIlent completed in 1992 and have the fOllowing i~formation. he plan/pro tile for Southeast 1.92nd Street (90-43) Shows a 18- i.n.ch dia. cross-eul.vert at Sta. 36+15. A floW direction arrow,' on the plan ;i.n.dicates the'flow is from south to north. The plan also shows the construction cif ~ '''special 'ditch and a dike to }:>e constructed along the south side of the road. It appears this ditch and diXe were constructed ~o insure flow was directed into the crOSS-CUlvert. A review 9f the field survey notes (co~y enolosed) do not show a cross culv~. A check of the elevations of the drivevay ~verts and side pipe(~) shows the elevations to be higher on the north side of the road. I a1so reviewed the 199Z drainage improvement oompleted by Roads KaintelliUlce as part of a school path proj,ect. The plans do not show the cross culvert. Improvement Plans sta. 3 ... 30 = BE l.92nd sta: 36+1.5. 'All flow to the north side of SE 192nd is conveyed easterly to 120th A~e BE. It is interesting that the basin map shows the flow from this project going south, just west of l.20th Ave SE., ' ' ' The problem was discussed in the Road ooordination meeting on April 2nd. Racheal Gutierrez, Roads Drainage Design will investigate further but I don't think much will come of it. ~e only concern voiced during the discussion, regarding abandoning the cross~culvert was the history'of road shoulder and ditch erosion east of 1.20th Ave SE. No information was pro~ided why the asbuilt does not match existing conditions'. I had Jacquie Little complete a more,*br.~ugA site inVestigation at the cross culvert. She walked the area between BB 192nd and the sehool site. A well defined channel was identified that app'ell.rs to have historically conveyed flows to the south onto the soh'ool site. The ohannel. ends where the school graded along the nortb property line. IT il I , h II I I I" t. 1 I FEB, 22, 2005 3:46PM KING CO, WLRD April 6, 1U6 Wilsey Hamilton Page 2 We did not oheek invert elevations in the t1P8 XI catch basin where the cross culvert is'loeated,but it appears from visual observation the cross cUlvert is lower than the pipe outlet to the east. 'Also becli.use Qf the entrance pipe fr'om the north it Would'seem the flow wouldqo south before 'any would flow east. Just because its .ore of a straiqht shot to the south. il~ not sure h~W much thi~ helps you with your project. xt appears from existinq'conditions some quantity of flo. does historically-flow, south to the school site. If a split' in the flows is appropriate that would prohabl:1 match existinq , conditions. Xf'the school wantlJ to elilli.i.nate all now to,'the south they will need to address Roads concern of :pot~ntial ' erosion prOblem east of 120th Sill. ,', If you need further information or I,can be of SOme other assistance please'qive me a oail On 6-8326. I~ J I', I TFEB, 22. 2005 i , j 3:46PIII--KING CO, WLRD ----NO, 0947 KING COUNTY SURFACE WATER MANAG,EMENT DIVISION DRAINAGE llNESTIGATION REPORT Page 1: INVESTIGATlON'REQUEST P" 11/19 MA I , ' ece"Ned by: I Date: B /26/,,} e:,OK'd by: 1) ~ FBe-No. I ' ' , 'Reoeived "DIP; PI .... print plainly lor =nnInll), (Day) , (Eve) d SP 27'1,113 i , ~ Cp.rAf/1 1f;.S .t7I'V S Plirt name: jl/fJr.ff, cJ,)e S LotNe: )3 Block No: agencies involved: No Field Investigation Needoo __ _ D/SppsmON: Turned to __ on ____ by __ _ OR: No further aCllon recommended because: Ii' Leacl agency has been, notified: roblem has been cOlTected. -::"'No~pr:-:-o"bl""'em-ch-::-:as'--;b-e~en::-·"'lde-:-::n-:;!ffi;;-le-:;d.---::P::Cr""io""'r '-in-ve:-:stlOCg:-a~tio:-::n-a-'d'7dre-ss'--:"es:-p:-:-roblem: Se. File #. ___ ~_ Private,problem -NDA? wiD not consider becwse: Water originates onstte and/or on neighboring parcel Location is outside SWM Service Area. _ Other (Specify): it ,DA~E CLoSED: -1.; ;! 1 j?/ by: --B . I!' -1t!c/.iU-rb I Ii i~ , I' I, I~ i I' I _!1EB,22. 2005 3:46PM p, 12/19KINGCO. WLRD -.•• '"'=I1Wi'fiSi8IMj " ,"WIQ'Y·1NO. 0947 ns J...l.Nnoo 0Nf>I . 1 "-__ ~w -."~; ...... , I I I i i KIn; County Surface Wal", Man..gemllhl TIll'AGB DRAINAGE INVESTIGATION REPORT FIELD INVESTIGATION PHONE ~~~L-__ nOIL PAGB lOSW MAlN't DIVISION _4_ DATE; =7=,-_~i 1NlI'IALS. I I lITE VltlT ON .-"~ .. !'LUGIIED DRAINAGI CROSS CULVERT· INYUTlQATlON FOUHD tlG:Nt OF IlRlvewAY BEING. WASIWI OUT I<T 1t121 -1:MnI I<VE tE. . N U' CONCRETE DRIVEWAY CULV2IIT 11''''' FOUND TO Ie I'\ILL 01' "~IM~NT ~D GUVEL WHICH IS R~STRleTlNCI FI.OWL DURING INVEmGATlON ONLY A 8lllAU UoIOUNT ON WATER WAS PASSING THROUGH THE: PIPE. PHOTOS TAKEN # 1 LC!)KlHQ AT DRIVEWI<Y ~D SICIHS 01' WASHING. OUT CI<USED BY PLUGGED CULVERT. a LOOIONQ AT IIP8TREAU END OF CULV!RT IMPACTED WITH SKETCH: ARU IEING WUHm OUT ftQA.D8IPE DMlHAtlli: __ _ -------- SE 192ND ST t . i f, REB,22.2005 3:46PM mG co, I'ILRD---'-:-" -:-:-'-------------,-NO,0947 - i~: ' lJRAl.NAGE INVESTfGAIlON REpORT p, 13!1~ geht it . i : -" Page 1: INvEsTIOATIONREQUESf ' PROBLEM: ~~ Type • .".k"--,-,_ DlIY: tid Date: '1/1. ADDRESS: ,tt DIU, flU ~ Ii' OK'dby:~ FILENo. ctg-()OI9' Day) ! 4'2'5) PHON!! ::s ~ -k.'2Q I CitytZ~, Eve): C</1h )' 22-& ;.. q~ 72. State'---_ Zip qa"5K Locmon 'of problem, if different: I ' I 1 'i kepQrted Problem: CALL FIRST II (Would Like To Be Pr~ VJorK~ I ' , , 4 Ib-Ivr ~ ) M67W i;~ rr;d~ N.it~, pwf' ~ y1) ()c. -n'!I (LI'\O! I)l;(.J-W 601 [~ (Q !'l:tv [r1t r 1 ~~'r~(rJDrJtJ?1dc). , j' j' I r I ' !~ Jlatn~e: N~~ ~ f1!--1J1'v-t Lot No: r:P BloctNo:L i' , Other ag~ncies involved: 2.o5~ No field investigation ~7-:---:-:- i (1I11t!W) I ' Parcel No_ ttl '18'40-0(1.'5 Th.Bros: New (ilk E:Z. Old 41. I-t-5 Basin 171..-¥-Council District ~ Charge No. REsPONSE: Citizen norl£ed on' I~ 21-q 8 by: V phone ~ letter _' _ in person I I . i , I p\,,~,,;ie. ?r-o\:.\e.'fV\, '5v..~~I!.!:>f~r1 p ..... -r)'1 il-1te..rc:.e.rf" .... d:f~h E: WE> 'f K. ...,) i +J... Yle,.: ~ \.'d~1) Y' 'rf 0.. to Ie.. to. DISPOSITION! Turned to ~ on _-,1,--.... 1,--_ by_OR: No further action recommended because: Ii ' Lead agency has been notified: __ """':"':_:----:----:-:--'-:~:--_-=-_:__:____:___:_---,.---- 1 _ 'Problem hasoeen corrected. _ No problem has been identified, _ Prior investigation addresses problem: I 'SEEFn.E#, -$- Private problem -NDAP will riot consider because: K Water originates onsite and/or on neighboring parcel. . LocationisoutsideWLRDS~"-_Other (Specify): DATE CLOSED: ? 1 3 1:7 r ,By: ---AI 1 " I 1l " " " ,', j! I 'I I ~ '~1 I~ i iii 1 I' i I, I ' KI NG CO, WLRD NO,0947 p, 14/19 ,~I, FEB, 22. 2005 3: 46PM iii t i.~ ,- 1 Complaint 98-0019 Weldon Investigated by IWbert MaIms 011 1-16-98 Mari~ Weldon told me that water OOIllOS orito her property now because ofthe gravel fill put in by her leighbor. ,Th~ Deighbor at # 19022 built his hollSe 3-4 years ago and put in the gravcl4rll'eway at that tUne. He had to bring in fill fur the f01JDdatirm and parkiDg area. Aocording to Weldon be.still brings in gravel - i doe to the ~ sinking , ' I I found standing water on the neighbors property and small puddles and streamlets in the Weldon's pasture. It appears that prior to development that the ground was boggy with water on it, in the area of concern. Now the gravel fill bas reduc-ed the boggy area,. thus pushing more oftbe water onto Weldon's '- slope 4'BarilWucFence Horse paSIme NTS I wH2o ... vuw..u,s c . Fill PondingHZo I EJ 11(;'" Ave. BE t 3: I i i j, I i 1 I 1 , , I I I l" " II • , ' sa/ ...M~..L ,'. . I, ~ S. T :it iarcel No. C,!?9t2!Jr2/ J'tJ Kroll .1;.l754J Th.Bros: New NI Old '1,2/15".85 Basin c./fA/ '. CounciIDistrlctL ChargeNo. ___ ~ __ _ II I . ~NSE": Citizen notified on (-12. ~9 't by: _ phr;>ne __ letter -.2:s::.... in person I '. • J-.~ClrH:,"/J7..I.K.N'w ~i-IDf ~t1rr M--8Je-:tl ..f) .1;'17'1/ &QS~O ~p Rt7f7r;Ht ~.j((JIIlt>.J' 1?,V/f/lW /fJ t!1f17~~ !/KI9.u.t,<p6c i!');.( SF IP~N'/)sr 6i2 13t.Qd~l/~ -e ~ , i DISPOSITION: Thmed to on I I by...:....-OR: No further action recommended because: 1&. Lead agency has been not;ffl.ed: [0 ~ S' d1.fr ,tJ/ 01 Ii 4-: . L..... Problem has been corrected. _. ._ No proolem has been idartified. _ Prior investigation addn::sses JlIC1blern: s.u FILE 1/ . i _. Pnvate problein -NDAP will not consider because: Water originates onsite and/or on neighboring parcel. Location is outside WLRD7Z1ervi ' _. _Other (Specify): i IDATECLOSED: ~ [ ?5ft t 9· By:' P!/Jf. KING CO, WLRD ~r--I FEB, 22. 2005 3:47PM L--'-.-""--" --~c..:.-~~" ! ' KING CotJNTY Department of Natllrld RGsources Watar and L.and Reeouree Division NO,0947 FJ:q; NO. ,98:'0926 jAMB ClARY VANGO ADDRESS 1&133 '. 121ST pL SE, p, 16119 DRAINAGE INVESTIGATION REPORT l'HONE (258)864.28'9 . TB PAGB.l!.l!. "'B~:-=I"---i i FIELD INVESTIGATION KROLL PAGS S05W MAJNI: DIVISION ....!........ DATB 1.22-99 lNITlALS-MAM DETAILS OF INVESTIGA.TION; , ; i~' ' SITE VISIT ON ,., ..... STREET DRAlNAQE BLOOKED CAUSING DRAINAGE SYSTEM ON PRIVATE qOAD TO BACK UR, • INVES11aAnON FOUND THE DRAINAGE SY$TEM ON u.ST PL SE HAS A CONTROL STRUCTURE WHICH DRAINS TOA ' N I, CATOH UBIN IN THE ROAD RIGHT·OF·WA'L THE SUD. GATE FOR THE snTEII WAS OPEN WHIOH ALLOWS FOR WATER TO Flow INTO SYSTEM FROM STREET OATOH BASiN. OLOSED SUDe GATE AT TI'I18 TIME. INoPECTED STREET );ITS DRAlNAIn ON SE 1nND ST JUST EAST OF n,ST PL SE FOR AllY BLOCKAGE. WHEN UNE IVAS OANDLED LIGHT REFLECTED BACK. THERE APPuutS TO BE A METAl: OBJECT A80UT ;0' DOWN THE UNE. TAlKlD TO COMpLAINANT IT WAS SIiGGiESTED SUDE GAT!! BE KEPT OLOSED TO PREVENT A BACK WASH INTO PRIVATE SYSTEM. MENnONED A' MEMO WOULD BE SENT TO ROA\l$ 10 HAVE THeM IKVESTIGATE OBJECT IN PIPE. ' ' NO PHaro!! TAKEN I-iOUliiE' ,,, .. w m a.. I- m ... N ... v ~~ SE 192ND ST L. CANb~ PJpe NOTED SOME TYPe OF BLOCKAGE l.IGlHi REFl.EeTSl 9A,eK I L-____ ~ ______ ~ ________________________________________________ ~ I i I , I i I I I i I i APPENDIX F Aerial Photos Water Quality/Flow Control Map 0 i a coI- l coO • , NI ~ ~ 8 2:0.. z " ~ ~ ~ .s UJ ~ z z ~ • ~ '" a..N ... J ~ ® (!) ~ h i ~ O UJ ~ ~ 00 u; < ~:::«< ( f) «N UJ .., z ~ Iw ~ ro--l 1: c roC) ~ , N W I ~ 8 " I 0 fa mID t cei! 1 z z a !> o..(f) z a ~ ~ } ~ m ~ ill ~ .. tOO ~ ~ If. (J 8 S OW < « "« <-: 1-' < 0 ~ I I !. ~ cb ....... .:'! L-....: r" I, . BASIC I' A04PM288 1998 MANUAL NTOWl'I$hIPUnes 5-T-R OSUNES ~ SEQJNES I\ITWPUNFS NS\ruB1s Water Bodies L_ j Parcels Cities Seosltlve Slope Level 2 Areas C2JDA CJ ERS Landailde Hazard Level 2 Areas DA lJ<D Area Specific Flow Control ReQUIrements Level 1 Fe Area 1'">1 Level 2 FC Area Level 3 Fe Area Basin-wide Flow Control Requirel118fltsoLevel1FeAraoI ffiEJ Level 2 Fe Araa N City Boundaries o 4Q{) Feel I"" 500 Feel King Countv 1II.ubJ1Ic:! 10 Plot date: Dec 7, 2004; \lddesOO1\1101'Q1s'av_deVlproj6Cls\baSe2,apr APPENDIXG Preliminary Detention Pond Calculations Preliminary Water Quality Pond Calculations Preliminary Detention Pond Calculations Detention Pond Summary Pre-Developed Land Use Condition 10.94 0.00 0.000000 0.00 0.00 0.000000 0.00 0.00 0.000000 0.000000 Till Forest Till Pasture Till Grass Outwash Forest0.00 0.00 0.00 0.00 0.00 0.00 0.00 O. 00 0.00 0.00 0.000000 Outwash Pasture 0.000000 Outwash Grass 0.000000 Wetland 0.000000 Impervious predev. tsf ST 1. 00000 Flow Frequency Analysis Time Series File:predev.tsf Project Location:Sea-Tac Annual Peak Flow Rates--------Flow Frequency Analysis------- Flow Rate Rank Time of Peak CFS) 0.690 2 2/09/01 18,00 0.lB7 7 1/06/02 3,00 0.511 4 2/28/03 3,00 0.018 8 3/24/04 20,00 0.304 6 1/05/05 8,00 0.530 3 1/18/06 21,00 0.447 5 11/24/06 4,00 0.883 1 1/09/0B 9,00 Computed Peaks Developed Land Use Condition 2.94 0.00 0.000000 0.00 0.00 0.000000 3.32 0.00 0.000000 0.00 0.00 0.000000 0.00 0.00 0.000000 0.00 0.00 0.000000 0.00 0.00 0.000000 4.38 0.00 0.000000 dev. tsf ST 1. 00000 Flow Frequency Analysis Time Series File:dev.tsf Project Location:Sea-Tac Peaks Rank Return Prob CFS) Period 0.883 1 100.00 0.990 0.690 2 25.00 0.960 0.530 3 10.00 0.900 0.511 4 5.00 O.BOO 0.447 5 3.00 0.667 0.304 6 2.00 0.500 0.187 7 1. 30 0.231 0.018 8 1.10 0.091 0.818 50.00 0.980 Till Forest Till Pasture Till Grass Outwash Forest Outwash Pasture Outwash Grass Wetland Impervious Annual Peak Flow Rates--------Flow Frequency Analysis------- Flow Rate Rank Time of Peak -Peaks Rank Return Prob CFS) (CFS) Period 1. 48 5 2/09/01 2,00 2.98 1 100.00 0.990 1.14 8 1/05/02 16, 00 1. 76 2 25.00 0.960 1. 76 2 2/27/03 7,00 1. 68 3 10.00 0.900 1. 25 7 8/26/04 2,00 1. 57 4 5.00 0.800 1. 39 6 10/28/04 16,00 1. 48 5 3.00 0.667 1. 57 4 1/18/06 16,00 1. 39 6 2.00 0.500 1. 68 3 10/26/06 0,00 1.15 7 1. 30 0.231 2_98 1 1/09/08 6,00 1.14 B 1.10 0.091 Computed Peaks 2.57 50.00 0.980 Detention Pond Sizing Type of Facility: Side Slope: Pond Bottom Length: Pond Bottom Width: Pond Bottom Area: Top Area at 1 ft. FB, Effective Storage Depth: Stage 0 Elevation: Storage Volume: Riser Head: Riser Diameter: Number of orifices: Orifice # Height ft) 1 0.00 2 5.00 3 6.25 Top Notch Weir: Outflow Rating Curve: Stage Elevation Detention Pond 2.00 H,lV 146.50 ft 47.00 ft 6BB6. sq. 15148. sq. ft ft 0.348 acres 8.00 ft 0.00 ft 82583. cu. Ft 90,500 cf provided 1.896 ac-ft B.OO ft 12.00 inches 3 Full Head Pipe Diameter Discharge Diameter in) (CFS) (in) 1. 50 0.173 2.75 0.355 6.0 1. 25 0.056 4.0 None None Storage Discharge Percolation ft) (ft) (cu. ft) (ae-ft) (efs) (efs) 0.00 0.00 o. 0.000 0.000 0.00 0.02 0.02 DB. 0.003 O.OOB 0.00 0.03 0.03 207. 0.005 0.01l 0.00 0.05 0.05 345. 0.008 0.013 0.00 0.06 0.06 415. 0.010 0.015 0.00 0.08 0.08 553. 0.013 0.017 0.00 0.09 0.09 623. 0.014 0.019 0.00 0.11 0.11 762. 0.017 0.020 0.00 0.13 0.13 902. 0.021 0.022 0.00 0.28 0.28 1958. 0.045 0.032 0.00 0.44 0.44 3105. 0.071 0.040 0.00 0.60 0.60 4272. 0.098 0.047 0.00 0.75 0.75 5384. 0.124 0.053 0.00 0.91 0.91 6590. 0.151 0.058 0.00 1. 07 1. 07 7817. 0.179 0.063 0.00 1. 22 1. 22 8986. 0.206 0.067 0.00 1. 38 1. 38 10253. 0.235 0.072 0.00 1. 54 1.54 ll541. 0.265 0.076 0.00 1. 69 1. 69 12768. 0.293 0.079 0.00 1. B5 1. 85 14096. 0.324 0.083 0.00 2.01 2.01 15447. 0.355 0.086 0.00 2.16 2.16 16732. 0.384 0.090 0.00 2.32 2.32 18124. 0.416 0.093 0.00 2.48 2.48 19538. 0.449 0.096 0.00 2.63 2.63 20883. 0.479 0.099 0.00 2.79 2.79 22339. 0.513 0.102 0.00 2.95 2.95 23817. 0.547 0.105 0.00 3.ll 3.ll 25317. 0.581 0.108 0.00 3.26 3.26 26744. 0.614 o .1l0 0.00 3.42 3.42 28288. 0.649 0.113 0.00 3.58 3.58 29855. 0.685 o .1l5 0.00 3.73 3.73 31344. 0.720 0.118 0.00 3.89 3.89 32955. 0.757 0.120 0.00 4.05 4. 05 34588. 0.794 0.123 0.00 Surf Area sq. ft) 6886. 6901. 6909. 6924. 6932. 6948. 6955. 6971. 6986. 7103. 7229. 7356. 7475. 7603. 7732. 7854. 7984. B115. B239. 8372. 8506. 8632. 8767. 8903. 9032. 9170. 9308. 9447. 9579. 9720. 9861. 9995. 10138. 10283. 4.20 4.36 4.52 4.67 4.83 4.99 5.00 5.03 5.06 5.09 5.11 5.14 5.17 5.20 5.23 5.39 5.54 5.70 5.86 6.01 6.17 6.25 6.26 6.28 6.29 6.30 6.32 6.33 6.34 6.35 6.51 6.67 6.82 6.98 7.14 7.30 7.45 7.61 7.77 7.92 8.00 8.10 8.20 8.30 8.40 8.50 8.60 8.70 8.80 8.90 9.00 9.10 9.20 9.30 9.40 9.50 9.60 9.70 9.80 9.90 4.20 4.36 4.52 4.67 4.83 4.99 5.00 5.03 5.06 5.09 5.11 5.14 5.17 5.20 5.23 5.39 5.54 5.70 5.86 6.01 6.17 6.25 6.26 6.28 6.29 6.30 6.32 6.33 6.34 6.35 6.51 6.67 6.82 6.98 7.14 7.30 7.45 7.61 7.77 7.92 8.00 8.10 8.20 8.30 8.40 8.50 8.60 8.70 8.80 8.90 9.00 9.10 9.20 9.30 9.40 9.50 9.60 9.70 9.80 9.90 36141. 37820. 39522. 41139. 42886. 44658. 44769. 45104. 45440. 45777. 46002. 46340. 46679. 47019. 47360. 49191. 50930. 52809. 54712. 56518. 58469. 59454. 59577. 59825. 59948. 60072 . 60320. 60445. 60569. 60693. 62697 . 64726. 66651. 68729. 70833. 72962. 74982. 77161. 79367. 81458. 82583. 83998. 85424. 86860. 88306. 89763. 91230. 92708. 94196 . 95695. 97205. 98725. 100255. 101797. 103349. 104912. 106485. 108070. 109665. 111271. 0.830 0.868 0.907 0.944 0.985 1. 025 1. 028 1. 035 1. 043 1. 051 1. 056 1. 064 1.072 1. 079 1. 087 1.129 1.169 1.212 1. 256 1. 297 1. 342 1. 365 1. 368 1.373 1. 376 1. 379 1. 385 1. 388 1. 390 1. 393 1.439 1.486 1. 530 1.578 1. 626 1. 675 1.721 1.771 1. 822 1. 870 1. 896 1. 928 1.961 1. 994 2.027 2.061 2.094 2.128 2.162 2.197 2.232 2.266 2.302 2.337 2.373 2.408 2.445 2.481 2.518 2.554 0.125 0.127 0.130 0.132 0.134 0.136 0.136 0.139 0.145 0.155 0.169 0.185 0.206 0.229 0.238 0.269 0.295 0.317 0.338 0.356 0.374 0.382 0.384 0.386 0.389 0.392 0.397 0.401 0.404 0.406 0.430 0.450 0.469 0.486 0.503 0.519 0.534 0.549 0.563 0.577 0.584 0.900 1. 470 2.210 3.010 3.300 3.560 3.810 4.030 4.240 4.450 4.640 4.820 5.000 5.170 5.330 5.490 5.640 5.790 5.940 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 10419. 10564. 10711. 10849. 10997. 11146. 11156. 11184. 11212. 11240. 11258. 11287. 11315. 11343. 11371. 11522. 11665. 11817. 11971. 12115. 12270. 12348. 12358. 12377. 12387. 12397. 12416. 12426. 12436. 12446. 12602. 12760. 12908. 13068. 13228. 13388. 13540. 13702. 13865. 14019. 14102. 14205. 14308. 14412. 14516. 14621. 14725. 14830. 14936. 15041. 15148. 15254. 15361. 15468. 15575. 15683. 15790. 15899. 16007. 16116. Hyd Inflow Outflow Storage Target Calc Peak Stage 8.28 8.03 6.92 6.72 6.32 5.28 4.68 3.19 Elev 8.28 8.03 6.92 6.72 6.32 5.28 4.68 3.19 Cu-Ft) (Ac-Ft) 1 2 3 4 5 6 7 8 2.98 ******* 2.06 86564. 1.987 1.48 0.69 1.68 ******* 1.76 ******* 1.57 ******* 1.39 ******* 1.14 ******* 1.15 ******* 0.69 0.48 0.46 0.40 0.25 0.13 0.11 83052. 67935. 65377 . 60324. 47979. 41265. 26059. Route Time Series through Facility Inflow Time Series File:dev.tsf Outflow Time Series File:rdout Inflow/Outflow Analysis Peak Inflow Discharge: Peak Outflow Discharge: Peak Reservoir Stage: Peak Reservoir Elev: Peak Reservoir Storage: 2.98 CFS at 6:00 on Jan 2.06 CFS at 10:00 on Jan 8.28 Ft 8.28 Ft 86564. Cu-Ft 1.987 Ac-Ft Flow Duration from Time Series File:rdout.tsf 1. 907 1.560 1. 501 1.385 1.101 0.947 0.598 9 in Year B 9 in Year 8 Cutoff Count Frequency CDF Exceedence_Probability CFS % % % 0.010 0.029 0.049 0.068 0.087 0.107 0.126 0.145 0.165 0.184 0.204 0.223 0.242 0.262 0.281 0.300 0.320 0.339 0.359 0.378 0.397 0.417 0.436 0.455 0.475 0.494 0.514 0.533 0.552 0.572 0.591 0.610 0.630 0.649 0.669 0.688 36764 6426 5628 4587 3203 2078 1361 754 63 53 37 28 53 38 22 22 18 18 23 27 24 19 9 14 10 8 9 6 5 6 5 o o 1 o a 59.954 10.479 9.178 7.480 5.223 3.389 2.220 1.230 0.103 0.086 0.060 0.046 0.086 0.062 0.036 0.036 0.029 0.029 0.038 0.044 0.039 0.031 0.015 0.023 0.016 0.013 0.015 0.010 0.008 0.010 0.008 0.000 0.000 0.002 0.000 0.000 59.954 70.434 79.612 87.092 92.316 95.704 97.924 99.154 99.256 99.343 99.403 99.449 99.535 99.597 99.633 99.669 99.698 99.728 99.765 99.809 99.848 99.879 99.894 99.917 99.933 99.946 99.961 99.971 99.979 99.989 99.997 99.997 99.997 99.998 99.998 99.998 40.046 29.566 20.388 12.908 7.684 4.295 2.076 0.846 0.744 0.657 0.597 0.551 0.465 0.403 0.367 0.331 0.302 0.272 0.235 0.191 0.152 0.121 0.106 0.083 0.067 0.054 0.039 0.029 0.021 0.011 0.003 0.003 0.003 0.002 0.002 0.002 0.400E+00 0.296E+00 0.204E+00 O.129E+DO 0.768E-01 0.430E-Ol 0.208E-01 0.846E-02 0.744E-02 0.657E-02 0.597E-02 0.551E-02 O.46SE-02 o .403E-02 0.367E-02 0.331E-02 0.302E-02 0.272E-02 0.235E-02 0.191E-02 0.152E-02 0.121E-02 0.106E-02 0.832E-03 0.669E-03 0.538E-03 0.391E-03 0.294E-03 0.212E-03 o .1l4E-03 0.326E-04 0.326E-04 O.326E-04 0.163E-04 O.163E-04 0.163E-04 Paused ~ Our-atlon AnalYS15 -KCRTS r:l[01&] ci fi) LL 01 u ciIn is 10 ., R 000 00 0 I I IIII 10 '·4 I IIIIII 10 ·3 I I I II 10 ·2 Probability Exceedence Duration Comparison Anaylsis Base File: predev. tsf New File: rdout.tsf Cutoff Units: Discharge in CFS i I IIIII 10 ·1 rdout,dur 0 target dur • I I I I I I II 10' Fraction of Time--------------Check of Tolerance------- Cutoff Base New %Change Probability 0.153 0.93E-02 0.80E-02 -14.5 0.93E-02 0.194 0.62E-02 0.62E-02 0.0 0.62E-02 0.235 0.49E-02 0.50E-02 2.3 0.49E-02 0.277 0.37E-02 0.37E-02 1.3 0.37E-02 0.318 0.2BE-02 0.30E-02 7.5 0.28E-02 0.359 0.22E-02 0.23E-02 7.5 O.22E-02 0.401 0.15E-02 0.15E-02 2.2 0.15E-02 0.442 0.10E-02 0.99E-03 -1. 6 0.10E-02 0.484 O.62E-03 O.59E-03 -5.3 0.62E-03 0.525 0.34E-03 0.31E-03 -9.5 0.34E-03 0.566 0.21E-03 0.lSE-03 -30.8 0.21E-03 0.60B O.16E-03 0.33E-04 -80.0 a.16E-03 0.649 0.98E-04 0.16E-04 -B3.3 O.9BE-04 Maximum positive excursion = 0.016 cfs 4.9%) occurring at 0.317 cfs on the Base Data:predev.tsf and at 0.332 cfs on the New Data:rdout.tsf Maximum negative excursion = 0.084 cfs (-12.6%) occurring at 0.666 cfs on the Base Data:predev.tsf and at 0.582 cfs on the New Data:rdout.tsf Base New %Change 0.153 0.13 B -9.4 0.194 0.194 0.0 0.235 0.238 1.2 0.277 0.280 1.2 0.318 0.334 4.9 0.359 0.367 2.0 0.401 0.405 1.0 0.442 0.441 -0.3 0.484 0.480 -0.8 0.525 0.517 -1.6 0.566 0.552 -2.5 0.608 0.562 -7.4 0.649 0.577 -11.2 Flow Frequency Analysis Time Series File:rdout.tsf Project Location:Sea-Tac Annual Peak Flow Rates--------Flow Frequency Analysis------- Flow Rate Rank Time of Peak --Peaks --Rank Return Prob CFS) (CFS) (ft) Period 0.689 2 2/09/01 20,00 2.06 8.28 1 100.00 0.990 0.132 7 12/29/01 11 ,00 0.689 8.03 2 25.00 0.960 0.456 4 3/06/03 22,00 0.479 6.92 3 10.00 0.900 0.109 8 8/26/04 7,00 0.456 6.72 4 5.00 0.800 0.248 6 1/05/05 16,00 0.397 6.32 5 3.00 0.667 0.397 5 1/19/06 0,00 0.248 5.28 6 2.00 0.500 0.479 3 11/24/06 8,00 0.132 4.68 7 1.30 0.231 2.06 1 1/09/08 10,00 0.109 3.19 8 1.10 0.091 Computed Peaks 1.60 8.22 50.00 0.980 Preliminary Water Quality Pond Calculations Volume runoff from lill Grass = Volume runoff from lill Forest = Volume runoff from impervious = 3.32 Ac x 0.47 in. x 0.25/12 = 0.0325 Ac -It. 2.94 Ac x 0.47 in. x 0.10/12 = 0.D115 Ac -It. 4.38 Ac x 0.47 in x 0.90/12 = 0.1543 Ac -It. Total runoff volume VR = 0.1983 Ac -It. Wetpool volume Volume Factor Total basin volume VB = 0.1983 x 3 = 0.5949Ac -It = 26,000 cf 30,500 cf provided HYDROLOGIC ANALYSIS FOR JESSIE GLEN EXISTING DRAINAGE BASIN PROJECT DATE Total Area: Jessie Glen April 13, 2006 Impervious Area (using 6.5 Dwelling Units/Acre = 54%): Pervious Area: KCRTS Calculated Flow: Storms Flow (cis) 36.50 acres 16.80 acres 19.70 acres 2 year 5 year 24 hr 24 hr 4.78 5.95 17% zoned as R-8. 83% zoned as R-6) 10 year 24 25 year 24 50 year 24 100 year hr hr hr 24 hr 6.75 7.77 8.55 9.34 PART E. -WATER QUALITY SYSTEM The project site will have a wetpond for treating stonnwater ftows for Basic Water Quality as identified on the King County Water Quality Treatment Areas Map. The enhanced water quality standard will not be required for the Jessie Glen project because the development does not exceed 8 units per acre when considering lot area only. The proposed Jessie Glen development has 49 lots in 6.57 acres lot area which results in 7.46 units per acre. The design calculations are attached following this section. Table 5 below summarizes the parameters for the proposed wetpond. Table 5 -Wetpond Bottom Length (feet) 180.00 Bottom Width (feet) 50.00 Side Slope, Z 2:1 Bottom Elevation (feet) Varies Top of Wetpond Elevation (feet) 496.25 Required Wetpond Volume (cubic feet) 26,763 Available Wetpond Volume - 2 cells (cubic feet) 33,043 A riprap pad will be provided as an energy dissipater for the storm drainage pipe discharging into the combined wetpond and detention stonnwater facility. KCRTS/RUNOFF CALCULATIONS JESSIE GLEN DRAINAGE BASINS FOR KCRTS/RUNOFF CALCULATIONS PROJECT DATE Jessie Glen August 4, 2005 Existing Drainage Basin Till Forest Area Offsite Till Forest Area Total Existing Drainage Basin Area Proposed Drainage Basin Offsite Till Forest Area Till Grass Area Lot Impervious Area Road Impervious Area Open Space Impervious Area Pond Tract Impervious Area Total Impervious Area Total Proposed Drainage Basin Area KCRTS/Runoff Calculated Flow: Storms 2 year 24 hr Existing Flow (cfs) 0.260 Proposed Flow (cIs) 1.420 5 year 24 hr 0.405 1.790 335214.00 tt' = 128221.00 tt' = 463435.00 tt 2 = 128221.00 tt' = 133647.28 tt' = 114856.00 tt' = 62061.42 tt' = 5756.40 tt' = 18892.90 tt' = 201566.72 tt' = 463435.00 tt' = 10 year 25 year 24 hr 24 hr 0.507 0.641 2.040 2.360 1:IESM-JOBSI116610011005IworksI2005-08-04 KCRTSlkcrtsan.xls 7.70 acres 2.94 acres 10.64 acres 2.94 acres 3.07 acres 2.64 acres 1.42 acres 0.13 acres 0.43 acres 4.63 acres 10.64 acres 50 year 100 year 24 hr 24 hr 0.744 0.848 2.600 2.850 Job No. 1166-001-005 Flow Frequency Analysis LogPearson III Coefficients Time Series File:existing.tsf Mean= -0.590 StdDev~ 0.233 Project Location:Sea-Tac Skew~ -0.136 Annual Peak Flow Rates--------Flow Frequency Analysis------- Flow Rate Rank Time of Peak --Peaks Rank Return Prob CFS) (CFS) Period 0.315 16 2/16/49 22:00 0.7l6 1 89.50 0.989 0.615 5 3/03/50 16:00 0.676 2 32.13 0.969 0.676 2 2/09/51 18:00 0.641 3 19.58 0.949 0.212 32 1/30/52 9:00 0.627 4 14.08 0.929 0.163 42 1/18/53 19:00 0.615 5 10.99 0.909 0.238 28 1/06/54 5:00 0.520 6 9.01 0.889 0.420 9 2/07/55 21:00 0.502 7 7.64 0.869 0.357 13 12/20/55 17:00 0.452 S 6.63 0.849 0.278 21 12/09/56 15:00 0.420 9 5.S6 0.829 0.295 20 1/16/58 20:00 0.420 10 5.24 0.S09 0.243 24 1/24/59 2:00 0.416 11 4.75 0.789 0.452 8 11/20/59 21:00 0.362 12 4.34 0.769 0.245 23 2/24/61 15:00 0.357 13 3.99 0.749 0.147 44 1/03/62 2:00 0.350 14 3.70 0.729 0.196 36 11/25/62 15:00 0.326 15 3.44 0.709 0.243 25 1/01/64 19:00 0.315 16 3.22 0.690 0.17l 40 ll/30/64 12:00 0.312 17 3.03 0.670 0.186 38 1/06/66 3:00 0.311 18 2.85 0.650 0.416 11 1/19/67 14:00 0.303 19 2.70 0.630 0.246 22 2/03/68 23:00 0.295 20 2.56 0.610 0.241 27 12/03/68 17: 00 0.278 21 2.44 0.590 0.204 34 1113/70 23:00 0.246 22 2.32 0.570 0.165 41 12/06/70 8:00 0.245 23 2.22 0.550 0.502 7 2/28/72 3:00 0.243 24 2.13 0.530 0.222 30 1/13/73 5:00 0.243 25 2.04 0.510 o . 241 26 1/15/74 2:00 0.241 26 1. 96 0.490 0.362 12 12/26/74 23:00 0.241 27 1. 89 0.470 0.223 29 12/03/75 17:00 0.238 28 1. 82 0.450 0.026 50 3/24/77 20:00 0.223 29 1. 75 0.430 0.193 37 12110/77 17:00 0.222 30 1. 70 0.410 0.116 46 2/12/7 9 8:00 0.217 31 1. 64 0.390 0.311 18 12/15/7 9 8:00 0.212 32 1. 59 0.370 0.172 39 12/26/80 4:00 0.208 33 1. 54 0.350 0.312 17 10/06/81 15:00 0.204 34 1. 49 0.330 0.303 19 1/05/83 8:00 0.202 35 1. 45 0.310 0.202 35 1124/84 11: 00 0.196 36 1. 41 0.291 0.097 48 2111/85 6:00 0.193 37 1. 37 0.271 0.520 6 1/18/86 21:00 0.186 38 1. 33 0.251 0.420 10 11/24/86 4:00 0.172 39 1. 30 0.231 0.158 43 1/14/88 12:00 0.171 40 1. 27 0.211 0.101 47 4/05/89 16:00 0.165 41 1. 24 0.191 0.716 1 1109/90 9:00 0.163 42 1. 21 0.171 0.627 4 4/05/91 2:00 0.158 43 1.18 0.151 0.208 33 1/27/92 17:00 0.147 44 1.15 0.131 0.2l7 31 3/23/93 0:00 0.122 45 1.12 0.111 0.060 49 3/03/94 4:00 0.116 46 1.10 0.091 0.326 15 2/19/95 20:00 0.101 47 1. OS 0.07l 0.641 3 2/09/96 1:00 0.097 48 1. 05 0.051 0.350 14 1/02/97 9:00 0.060 49 1. 03 0.031 0.122 45 1/07/98 11: 00 0.026 50 1. 01 0.011 Computed Peaks 0.848 100.00 0.990 Computed Peaks 0.744 50.00 0.980 Computed Peaks 0.641 25.00 0.960 Computed Peaks 0.507 10.00 0.900 Computed Peaks Computed Peaks Computed Peaks Computed Peaks 0.479 0.405 0.260 0.172 8.00 5.00 2.00 1. 30 0.875 0.800 0.500 0.231 Flow Frequency Analysis LogPearson III Coefficients Time Series File:develoEed.tsf Mean= 0.161 StdDev~ 0.113 Project Location:Sea Tac Skew~ 0.404 Annual Peak Flow Rates--------Flow Frequency Analysis------- Flow Rate Rank Time of Peak --Peaks Rank Return Prob CFS) (CFS) Period 1. 52 21 2/16/49 21:00 2.72 1 89.50 0.989 2.57 2 3/03/50 16:00 2.57 2 32.13 0.969 1. 59 19 2/09/51 2:00 2.48 3 19.58 0.949 1.15 42 10/15/51 13: 00 2.30 4 14.08 0.929 1.13 44 3/24/53 15:00 2.00 5 10.99 0.909 1. 39 27 12/19/53 19:00 2.00 6 9.01 0.889 1. 42 24 11/25/54 2:00 1. 94 7 7.64 0.869 1. 40 25 12/20/55 17:00 1. 85 8 6.63 0.849 1. 68 13 12/09/56 14 :00 1. 81 9 5.86 0.829 1. 44 22 12/25/57 16:00 1. 81 10 5.24 0.809 1. 08 47 ll/18/58 13: 00 1.77 II 4.75 0.789 1. 43 23 ll/20/59 5:00 1. 69 12 4.34 0.769 1. 25 35 2/14/61 21:00 1. 68 13 3.99 0.749 1. 19 39 ll/22/61 2:00 1. 66 14 3.70 0.729 1. 25 36 12/15/62 2:00 1. 65 15 3.44 0.709 1. 4 0 26 12/31/63 23:00 1. 63 16 3.22 0.690 1. 24 37 12/21/64 4:00 1. 63 17 3.03 0.670 1. 26 34 1/05/66 16:00 1. 62 18 2.85 0.650 1. 85 8 11/13/66 19:00 1. 59 19 2.70 0.630 2.00 5 8/24/68 16:00 1. 55 20 2.56 0.610 1.17 40 12/03/68 16:00 1. 52 21 2.44 0.590 1.27 32 1/13/70 22:00 1. 44 22 2.32 0.570 1. 22 38 12/06/70 8:00 1. 43 23 2.22 0.550 1. 94 7 2/27/72 7:00 1. 42 24 2.13 0.530 1.13 45 1/13/73 2:00 1. 40 25 2.04 0.510 1. 33 29 11/28/73 9:00 1. 40 26 1.96 0.490 1. 81 9 12/26/74 23:00 1. 39 27 1. 89 0.470 1. 17 41 12/02/75 20:00 1. 35 28 1. 82 0.450 1. 29 31 8/26/77 2:00 1. 33 29 1. 75 0.430 1.77 11 9/17/78 2:00 1. 30 30 1. 70 0.410 1. 55 20 9/08/79 15:00 1. 2 9 31 1. 64 0.390 1. 63 l7 12/14/79 21:00 1.27 32 1. 59 0.370 1. 66 14 11/21/80 11: 00 1.27 33 1. 54 0.350 2.30 4 10/06/81 0:00 1. 26 34 1. 49 0.330 1. 63 16 10/28/82 16:00 1. 25 35 1. 45 0.310 1. 35 28 1/03/84 1:00 1. 25 36 1. 41 0.291 1.12 46 6/06/85 22:00 1. 24 37 1. 37 0.271 1. 69 12 1/18/86 16:00 1. 22 38 1. 33 0.251 2.00 6 10/26/86 0:00 1. 19 39 1. 30 0.231 0.887 49 ll/11/87 0:00 1.17 40 1.27 0.211 1. 15 43 8/21/89 17:00 1.17 41 1. 24 0.191 2.72 1 1/09/90 6:00 1.15 42 1.21 0.171 2.48 3 11/24/90 8:00 1.15 43 1. 18 0.151 1. 30 30 1/27/92 15:00 1.13 44 1.15 0.131 0.827 50 11/01/92 16:00 1.13 45 1.12 o .lll 0.961 48 11/30/93 22:00 1.12 46 1.10 0.091 1.27 33 11/30/94 4:00 1. 08 47 1. 08 0.071 1. 81 10 2/08/96 10:00 0.961 48 1. 05 0.051 1. 62 18 1/02/97 6:00 0.887 49 1.03 0.031 1. 65 15 10/04/97 15:00 0.827 50 1. 01 0.011 Computed Peaks 2.85 100.00 0.990 Computed Peaks 2.60 50.00 0.980 Computed Peaks 2.36 25.00 0.960 Computed Peaks 2.04 10.00 0.900 Computed Peaks Computed Peaks Computed Peaks Computed Peaks 1. 97 1. 79 1. 42 1.19 8.00 5.00 2.00 1. 30 0.875 0.800 0.500 0.231 Flow Frequency Analysis Time Series File:rdout.tsf Project Location:Sea-Tac Annual Flow Rate CFS) 0.118 0.296 0.710 0.108 0.162 0.168 0.157 0.335 0.146 0.250 0.117 0.524 0.277 0.099 0.164 0.229 0.281 0.121 0.228 0.123 0.123 0.231 0.198 0.490 0.305 0.252 0.121 0.182 0.097 0.281 0.098 0.453 0.158 0.347 0.224 0.108 0.110 0.322 0.462 0.108 0.106 0.588 0.536 0.248 0.107 0.094 0.294 0.614 0.456 0.108 Peak Flow Rates--- Rank Time of Peak 38 14 1 42 30 28 32 11 33 20 39 5 18 47 29 23 17 36 24 34 35 22 26 6 13 19 37 27 49 16 48 9 31 10 25 43 40 12 7 41 46 3 4 21 45 50 15 2 8 44 computed Peaks Computed Peaks Computed Peaks Computed Peaks 2/22/49 3/05/50 2/09/51 2/04/52 1/23/53 1/07/54 2/08/55 1/06/56 2/26/57 1/17 /58 1/27 /59 11/21/59 11/24/60 12/24/61 11/27/62 11/19/63 12/01/64 1/07/66 12/15/66 1/20/68 12/11/68 1/27/70 12/07/70 3/06/72 12/26/72 1/16/7 4 12/27 /74 12/04/75 8/26/77 12/15/77 2/12/79 12/17/79 12/30/80 10/06/81 1/06/83 12/10/83 11/04/84 1/19/86 11/24/86 1/15/88 11/05/88 1/09/90 4/05/91 1/31/92 3/23/93 2/17/94 12/27/94 2/09/96 1/02/97 10/30/97 13:00 6:00 20:00 6: 00 7:00 20:00 15:00 11: 00 5:00 7:00 1:00 2:00 11: 00 5:00 1:00 17:00 2:00 4:00 8:00 22:00 7:00 3:00 11: 00 22:00 6:00 18:00 19:00 3:00 6:00 18:00 19:00 20:00 22:00 18:00 14:00 19:00 1:00 1:00 8:00 7:00 21:00 12:00 6:00 6:00 14: 00 21: 00 7:00 4:00 12:00 15:00 LogPearson III Coefficients Mean~ -0.682 StdDev~ 0.257 Skew~ 0.373 Flow Frequency Analysis------- Peaks - - CFS) (ft) 0.710 8.03 0.614 7.91 0.588 7.73 0.536 7.42 0.524 7.35 0.490 7.18 0.462 7.05 0.456 7.02 0.453 7.01 0.347 6.71 0.335 6.59 0.322 6.47 0.305 6.32 0.296 6.23 0.294 6.22 0.281 6.12 0.281 6.11 0.277 6.09 0.252 5.92 0.250 5.91 0.248 5.90 0.231 5.80 0.229 5.79 0.228 5.79 0.224 5.76 0.198 5.68 0.182 5.66 0.168 5.64 0.164 5.63 0.162 5.62 0.158 5.62 0.157 5.61 0.146 5.59 0.123 5.35 0.123 5.34 0.121 5.24 0.121 5.18 0.118 4.87 0.117 4.84 0.110 4.27 0.108 4.12 0.108 4.10 0.108 4.09 0.108 4.09 0.107 4.06 0.106 3.98 0.099 3.52 0.098 3.43 0.097 3.36 0.094 3.10 0.967 8.10 0.787 8.05 0.630 8.00 0.453 7.01 Rank Return Period 1 89.50 2 32.13 3 19.58 4 14 . 08 5 10.99 6 9.01 7 7.64 8 6.63 9 5.86 10 5.24 11 4.75 12 4.34 13 3.99 14 3.70 15 3.44 16 3.22 17 3.03 18 2.85 19 2.70 20 2.56 21 2.44 22 2.32 23 2.22 24 2.13 25 2.04 26 1. 96 27 1.89 28 1.82 29 1. 75 30 1. 70 31 1. 64 32 1. 59 33 1. 54 34 1. 4 9 35 1. 45 36 1.41 37 1. 37 38 1.33 39 1. 30 40 1. 27 41 1.24 42 1.21 43 1.18 44 1. 15 45 1.12 46 1.10 47 1. 08 48 1. 05 49 1.03 50 1.01 100.00 50.00 25.00 10.00 Prob 0.989 0.969 0.949 0.929 0.909 0.889 0.869 0.849 0.829 0.809 0.789 0.769 0.749 0.729 0.709 0.690 0.670 0.650 0.630 0.610 0.590 0.570 0.550 0.530 0.510 0.490 0.470 0.450 0.430 0.410 0.390 0.370 0.350 0.330 0.310 0.291 0.271 0.251 0.231 0.211 o . 191 0.171 0.151 0.131 0.111 0.091 0.071 0.051 0.031 0.011 0.990 0.980 0.960 0.900 Computed Peaks Computed Peaks Computed Peaks Computed Peaks 0.421 0.338 0.201 0.132 6.91 6.62 5.68 5.56 8.00 5.00 2.00 1. 30 0.875 0.800 0.500 0.231 DETENTION POND CALCULATIONS Retention/Detention Facility Type of Facility, Side Slope, Pond Bottom Length, Pond Bottom Width, Pond Bottom Area: Top Area at 1 ft. FB, Effective Storage Depth, Stage 0 Elevation: Storage Volume: Riser Head: Riser Diameter: Number of orifices: Detention Pond 2.00 H,lV 200.00 ft 71.50 ft 14300. sq. 22035. sq. ft ft 0.506 acres 5.50 ft 496.25 ft 95963. cu. ft 2.203 ae-ft 5.50 ft 12.00 inches 3 Orifice # Height ft) Diameter in) 1. 55 2.55 2.73 Full Head Discharge eFS) 0.153 0.265 0.217 pipe Diameter in) 1 0.00 2 3.25 3 4.35 Top Notch Weir: None Outflow Rating Curve: None Stage Elevation Storage ft) (ft) (cu. ft) (ae-ft) 0.00 496.25 o. 0.000 0.02 496.27 286. 0.007 0.03 496.28 430. 0.010 0.05 496.30 716. 0.016 0.06 496.31 860. 0.020 0.08 496.33 1148. 0.026 0.10 496.35 1435. 0.033 0.11 496.36 1580. 0.036 0.13 496.38 1868. 0.043 0.24 496.49 3463. 0.080 0.34 496.59 4925. 0.113 0.45 496.70 6545. 0.150 0.56 496.81 8179. 0.188 0.67 496.92 9826. 0.226 0.78 497.03 11487. 0.264 0.88 497.13 l3008. 0.299 0.99 497.24 14694. 0.337 1.10 497.35 16394. 0.376 1. 21 497.46 18107. 0.416 1. 32 497.57 19834. 0.455 1.42 497.67 21416. 0.492 1. 53 497.78 23169. 0.532 1. 64 497.89 24936. 0.572 1. 75 498.00 26717. 0.613 1. 85 498.10 28347. 0.651 1. 96 498.21 30154. 0.692 2.07 498.32 31975. 0.734 6.0 6.0 Discharge efs) 0.000 0.008 0.012 0.014 0.017 0.019 0.020 0.022 0.023 0.032 0.038 0.044 0.049 0.053 0.057 0.061 0.065 0.068 0.072 0.075 0.078 0.081 0.083 0.086 0.089 0.091 0.094 Percolation efs) 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 Surf Area sq. ft) 14300. 14322. 14333. 14354. 14365. 14387. 14409. 14420. 14441. 14562. 14671. 14792. 14913 . 15035. 15157. 15268. 1539l. 15514 . 15637. 15761. 15874. 15999. 16124. 16250. 16364. 16490. 16617. 2.18 2.29 2.39 2.50 2.61 2.72 2.83 2.93 3.04 3.15 3.25 3.28 3.30 3.33 3.36 3.38 3.41 3.44 3.46 3.49 3.60 3.70 3.81 3.92 4.03 4.14 4.24 4.35 4.38 4.41 4.44 4.46 4.49 4.52 4.55 4.58 4.69 4.79 4.90 5.01 5.12 5.22 5.33 5.44 5.50 5.60 5.70 5.80 5.90 6.00 6.10 6.20 6.30 6.40 6.50 6.60 6.70 498.43 498.54 498.64 498.75 498.86 498.97 499.08 499.18 499.29 499.40 499.50 499.53 499.55 499.58 499.61 499.63 499.66 499.69 499.71 499.74 499.85 499.95 500.06 500.17 500.28 500.39 500.49 500.60 500.63 500.66 500.69 500.71 500.74 500.77 500.80 500.83 500.94 501.04 501.15 501. 26 501. 37 501.47 501.58 501. 69 501.75 501.85 501.95 502.05 502.15 502.25 502.35 502.45 502.55 502.65 502.75 502.85 502.95 33810. 35659. 37351. 39227. 41117. 43021. 44939. 46695. 48640. 50600. 52394. 52934. 53295. 53837. 54381. 54743. 55289. 55835. 56199. 56748. 58766. 60614. 62660. 64721. 66797. 68887. 70800. 72919. 73499. 74081. 74663. 75052. 75637. 76222. 76809. 77397. 79561. 81542. 83735. 85943. 88166. 90200. 92453. 94720. 95963. 98045. 100140. 102247. 104367. 106500. 108646. 110804. 112975. 115159. 117356. 119566. 121789. 0.776 0.819 0.857 0.901 0.944 0.988 1.032 1.072 1.117 1.162 1. 203 1.215 1. 223 1. 236 1. 248 1. 257 1. 269 1. 282 1. 290 1. 303 1.349 1. 392 1. 438 1. 486 1.533 1.581 1.625 1. 674 1. 687 1. 701 1. 714 1. 723 1. 736 1. 750 1.763 1.777 1. 826 1. 872 1.922 1.973 2.024 2.071 2.122 2.174 2.203 2.251 2.299 2.347 2.396 2.445 2.494 2.544 2.594 2.644 2.694 2.745 2.796 0.096 0.099 0.101 0.103 0.105 0.107 0.110 0.112 0.114 0.116 0.117 0.120 0.125 0.134 0.146 0.160 0.178 0.197 0.203 0.208 0.227 0.244 0.260 0.273 0.286 0.299 0.310 0.321 0.326 0.334 0.346 0.362 0.381 0.403 0.429 0.439 0.469 0.496 0.521 0.544 0.565 0.586 0.605 0.624 0.634 0.959 1. 540 2.280 3.090 3.390 3.660 3.900 4.140 4.360 4.560 4.760 4.950 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 16744. 16871. 16987. 17115. 17243. 17372. 17502. 17619. 17749. 17880. 17999. 18034. 18058. 18094. 18130. 18153. 18189. 18225. 18249. 18285. 18417. 18537. 18670. 18803. 18936. 19070. 19192. 19327. 19364. 19400. 19437. 19462. 19499. 19536. 19573. 19610. 19745. 19869. 20006. 20142. 20280. 20405. 20543. 20681. 20757. 20883. 21010. 21137. 21264. 21392. 21520. 21648. 21777. 21906. 22035. 22165. 22294. 6.80 503.05 124025. 2.847 5.130 0.00 22425. 6.90 503.15 126274. 2.899 5.310 0.00 22555. 7.00 503.25 128536. 2.951 5.480 0.00 22686. 7.10 503.35 130811. 3.003 5.640 0.00 22817. 7.20 503.45 133100. 3.056 5.800 0.00 22949. 7.30 503.55 135401. 3.108 5.950 0.00 23080. 7.40 503.65 137716. 3.162 6.100 0.00 23213. 7.50 503.75 140044. 3.215 6.250 0.00 23345. Hyd Inflow Outflow Peak Storage Target Calc Stage E1ev (Cu-Ft) (Ac-Ft) 1 1. 57 ******* 0.67 5.51 501. 76 96181. 2.208 2 1. 79 0.64 0.61 5.36 501. 61 93085. 2.137 3 2.69 ******* 0.59 5.22 501.47 90196. 2.071 4 1. 94 ******* 0.46 4.65 500.90 78709. 1. 807 5 1. 91 ******* 0.48 4.73 500.98 80356. 1. 845 6 2.25 ******* 0.32 4.30 500.55 71867. 1. 650 7 1. 37 ******* 0.23 3.64 499.89 59496. 1. 366 8 1. 04 ******* 0.11 3.09 499.34 49477 . 1.136 Route Time Series through Facility Inflow Time Series File:developed.tsf Outflow Time Series File:rdout Inflow/Outflow Analysis Peak Inflow Discharge: 2.69 CFS at 6:00 on Jan 9 in 1990 Peak Outflow Discharge: 0.668 CFS at 20:00 on Feb 9 in 1951 Peak Reservoir Stage: 5.51 Ft Peak Reservoir Elev: 501. 76 Ft Peak Reservoir Storage: 96181. Cu-Ft 2.208 Ac-Ft Flow Duration from Time Series File:rdout.tsf Cutoff Count Frequency CDF Exceedence_probability CFS % % % 0.010 236319 53.954 53.954 46.046 0.460E+00 0.028 56928 12.997 66.951 33.049 0.330E+00 0.047 48741 11.128 78.079 21. 921 0.219E+00 0.066 38280 8.740 86.819 13 .181 o . 132E+00 0.085 28863 6.590 93.409 6.591 0.659E-01 0.103 16102 3.676 97.085 2.915 0.291E-01 0.122 9214 2.104 99.189 0.811 0.811E-02 0.141 637 0.145 99.334 0.666 0.666E-02 0.160 349 0.080 99.414 0.586 0.586E-02 0.179 298 0.068 99.482 0.518 0.518E-02 0.197 230 0.053 99.534 0.466 0.466E-02 0.216 487 0.111 99.646 0.354 0.354E-02 0.235 332 0.076 99.721 0.279 0.279E-02 0.254 244 0.056 99.777 0.223 0.223E-02 0.273 235 0.054 99.831 0.169 0.169E-02 0.291 187 0.043 99.874 0.126 0.126E-02 0.310 188 0.043 99.916 0.084 0.836E-03 0.329 112 0.026 99.942 0.058 0.580E-03 0.348 35 0.008 99.950 0.050 0.500E-03 0.366 15 0.003 99.953 0.047 0.466E-03 0.385 10 0.002 99.956 0.044 0.443E-03 0.404 10 0.002 99.958 0.042 0.420E-03 0.423 6 0.001 99.959 0.041 0.406E-03 0.442 26 0.006 99.965 0.035 0.347E-03 0.460 37 0.008 99.974 0.026 0.263E-03 0.479 16 0.004 99.977 0.023 0.226E-03 0.498 15 0.003 99.981 0.019 0.192E-03 0.517 22 0.005 99.986 0.014 0.142E-03 0.536 14 0.003 99.989 0.011 o .110E-03 0.554 10 0.002 99.991 0.009 0.868E-04 0.573 9 0.002 99.993 0.007 0.662E-04 0.592 11 0.003 99.996 0.004 0.411E-04 0.611 11 0.003 99.998 0.002 0.160E-04 0.629 4 0.001 99.999 0.001 0.685E-05 0.648 2 0.000 100.000 0.000 0.228E-05 0.667 0 0.000 100.000 0.000 0.228E-05 Duration Comparison Anaylsis Base File: existing.tsf New File: rdout.tsf Cutoff Units: Discharge in CFS Cutoff 0.131 0.176 0.221 0.266 0.311 0.356 0.401 0.446 0.491 0.537 0.582 0.627 0.672 Fractian of Time----- Base New %Change Check of Tolerance------- Probability Base New %Change 0.97E-02 0.74E-02 -24.0 0.97E-02 0.131 0.117 -10.9..( 0.50E-02 0.53E-02 5.5 0.50E-02 0.176 0.185 0.28E-02 0.33E-02 16.7 0.28E-02 0.221 0.233 0.17E-02 0.19E-02 13.3 0.17E-02 0.266 0.273 0.l1E-02 0.79E-03 -25.0 0.l1E-02 0.311 0.301 0.66E-03 0.48E-03 -26.8 0.66E-03 0.356 0.321 0.44E-03 0.43E-03 -3.1 0.44E-03 0.401 0.387 0.30E-03 O.32E-03 5.3 0.30E-03 0.446 0.451 O.2lE-03 O.2lE-03 -1.1 0.21E-03 0.491 0.490 0.11E-03 0.l1E-03 -4.0 0.l1E-03 0.537 0.530 0.59E-04 0.57E-04 -3.8 0.59E-04 0.582 0.580 0.32E-04 0.9lE-05 -71. 4 0.32E-04 0.627 0.601 0.68E-05 O.OOE+OO -100.0 0.68E-05 0.672 0.629 Maximum positive excursion = 0.017 cfs ( 9.4%) c... to.\) 'lo [OK] occurring at 0.184 cfs on the Base Data:existing.tsf and at 0.202 cfs on the New Data:rdout.tsf Maximum negative excursion = 0.020 cfs (-14.3%) occurring at 0.139 cfs on the Base Data:existing.tsf and at 0.119 cfs on the New Data:rdout.tsf 5.0 5.6 2.6 3.4 9.9 3.5 0.9 0.3 1. 3 0.2 4.2 6.3 I Dc\:\-~ \ ~ ~j w.~~'u-e \ @?1 o §) WETPOND CALCULATIONS Wetpond Calculations Volume runoff from 1111 Grass = Volume runoff from 1111 Forest = Volume runoff from impervious = Total runoff volume Wetpool volume Volume Factor Total basin volume 3.07 Ac x 0.47 in. x 0.25/12 = 0.0301 Ac -It 2.94 Ac x 0.47 in. x 0.10/12 = 0.0115 Ac -It 4.38 Ac x 0.47 in x 0.90/12 = 0.1632 Ac -It VA = 0.2048 Ac -It VB = 0.2048 x 3 = 0.6144 Ac -It = 26,763.26 cf 33,043 cf provided OVERFLOW CALCULATIONS ovc~~~ow (}AL/!.J.J.lJ.-r/ONS QO~r~w I: /()() 'fr. -/~ 1?U>1. ~ jl-e4.1..., 9.3'1 + L ~ ~~ 11.1f1' ~ y~ (;:tr( 6f) / J~ 0; 7.85 I Q ~ a 53"5 Cel ~~g ,l..H~ E-WeiR. eGlUlI;flOy.) H· 9.3+ .,. 0.315' ,: 'r. 6.2. I, 0.315 (')(r 2.CJl.'i)) (7.6'S) . i ..=::i) /00 yn It; m/~ . ~D1 ~ ':VJ1d-f'JWr i~~ -!.€>z· Ig:,e /NrUlW eJtl"at.lt..A110"; 1 ~ ~" SWI>H «&IJ''h I H .. a~71 EJ1.GI?~9£"1 OVe/f'FWW )PfL,J...WJfl( CAl CUc..A11oNS i <= {Qloo~.:z.III~] -.<..Jt H L -9.3'1-/1).2.1 C. '3$y~IzJ -Z.1f (. '35) go / 3.zl J 8t L c 15. 00 I . - e~~'I't'/~.lMt.J14, ~ IS' c)vtrft.aw FlttJU,~ ~ 'Pol. '15 ! JAI JM~@ ()~ Glwd/fJIA. -'iol.7'S + rJ.fI}1 ".?cR.lt~ 50;..1tZ+O.~ ~2Q.t.77! 70p 1 ~ ~ rt/~ :. $"0.<',77 +-O. ;3 c: 7()', ~7 7rJ-' Or !)t/?14 &.7'lNJ> cr 553.07 ,; 5.3.1 DETENTION PONDS -DESIGN CRITERIA FIGURE 5.3.I.B TYPICAL DETENTION POND SECTIONS control structure top width of berm 8 2..77 -emergency overflow WS I 6' min. t-2. 4 12'/15' min. for D D • 2. -overflow WS~ 'access road j '7~ pond deSign'-'W~S~~~V~V~~:jij~jmirmmmmrrm~ 0.67 1 I debris barrier~I-;'i- berm embankment existing ground profile _ ------ see figure 4.2.1.0 " ¥n=~-l -------, V 6" sediment storage pond desiQn W.S. ey, if required maximum elevation 10-yr W.S. SECTION A-A NTS 11111111 A A v v SECTION a-a NTS circumference length of opening sized for 100 yr flow overflow W.S. v Frame/grate for seconda ry inlet rame @ ms Provide vertical bars in f 4" O.C. (other flow syste acceptable if approved by DOES) See also the separate overflow structure shown in Figure S.3.1.C SECTION B-B has 2 options I. . L • I 10 (as required for 6" depth) m~~iLi;;:::=:=:;;;~=:::21 1 t 10 emergency overflow water surface see Figure 5.3.1.E) Qv~e~rf~lo~w~w~s~i§~~~~1~-~~~-'~~~~~~~~~~~~~~~~~~~~~~~ '" 1'min i nWS. SECTION B-B overflow WS 2005 Surface Water Design Manual 1' rock lining Emergency Ovetflow Spillway NTS emergency overflow WS y compacted embankment 5-27 SECTION C-C NTS rock lining per Table 4.4.1.A 1/24/2005 SECTION 5.3 DETENTION FACILITIES 5.3.1.2 METHODS OF ANALYSIS 1/24/2005 Detention Volume and Outflow The volume and outflow design for detention ponds shall be in accordance with the performance requirements in Chapler I and the hydrologic analysis and design methods in Chapter 3. Restrictor orifice structure design shall comply with Section 5.3.4 (p. 5-38). Note: The design water surface elevation is the highest elevation that occurs in order to meet the required outflow performance for the pond. Detention Ponds in Infiltrative Soils Detention ponds may occasionally be sited on till soils that otherwise meet the basic criteria of "sufficient permeable soil" for a properly functioning infiltration system (see Section 5.4.1, p. 5-57). These detention ponds have a surface discharge and may also utilize infiltration as a second pond outflow. Detention ponds sized with infiltration as a second outflow must meet all the requirements of Section 5.4 for infiltration ponds, including a soils report, performance testing, groundwater protection, presettling, and construction techniques. Emergency Overflow Spillway Capacity The emergency overflow spillway weir section shall be designed to pass the 1OO-year runoff event for developed conditions assuming a broad-crested weir. The broad-crested weir equation for the spillway section in Figure 5.3.I.E, for example, would be: li2 3/2 5/2 Q100 = C (2g) ['/J LH + 8/15 (Tan e) H ) where QIOO C g L H e peak flow for the 100-year runoff event (fps) discharge coefficient (0.6) gravity (32.2 ftIsec 2) length of weir (ft) height of water over weir (ft) angle of side slopes Assuming C = 0.6 and Tan 8 = 3 (for 3:1 slopes), the equation becomes: 3/2 5/2 3.21 (LH + 2.4 H ) 5-1) 5-2) To find width L for the weir section, the equation is rearranged to use the computed QlOo and trial values of H (0.2 feet minimum): L OS min. 312 QIOO / (3.21 H ))-2.4 H or 6 feet minimum FIGURE S.3,l,E WEIR SECTION FOR EMERGENCY OVERFLOW SPILLWAY Tof SCf"ji; C L. S"03. 07' emergency overflow 7 water surface 1 0.2' min. H T----' q:a~:6'DJ,ELg~~~~1 \per Table 4.4.1 A 5-3) overflow water surface 2005 Surface Water Design Manual 5-30 SECTION 5.3 DETENTION FACILITIES 1124/2005 Riser Overflow The nomograph in Figure S.3.4.H may be used to determine the head (in feet) above a riser of given diameter and for a given flow (usually the I OO-year peak flow for developed conditions). 100 0 0 Il. - 10 e s 0 1 FIGURE S.3.4.H RISER INFLOW CURVES 72 54 48 1 '" L; 7 I ~ I ........ " /// ~ ./ ~ II 1/ ./ ~ 36 1 J..; 1/ V-i.-' fIb/ ~3;v' ~/ I rv; V \ .. / 1// V J 27 ~ V :rrl/ VV (/ w'/": ~24;/ V~ I/. V~ ~ t/ (/2V ~ ~VI ~V V II ~-~ 1,/18 (j k / y 7" V- I 'I rIJ V V I 1f!fIIJ. J..; /" ~ L,l-' I Ill. 'J V • ~ V Il///IJ. V V I V ... y / Ih !!I//'I V V /1 ~1I117JV ~ IfA ~ ~ rI 1/1/ l7 I 'I y I r'IJJ 0.1 V 1/ r/; I 1 10 HEAD IN FEET (measured frolTl.crest of riser), I i"Qw'i,=9.739 DH 3I2 ~ H "'" 0, i" 7 2' "'1I.i Qorifice=3.782D H Q in cfs, 0 and H in feet Slope change occurs at weir-orifice transition 2005 Surface Water Design Manual 5-48 I SECTION 6.4 WETPOOL FACILITY DESIGNS FIGURE 6.4.4.A COMBINED DETENTION AND WETPOND (CONTINUED) slope vegetation per detention facility requirements access road per detention facility requirements submerged inlet inlet erosion contr'ol/-~ slope protection per detention facility requirements sediment storage depth = l' min. outlet pipe invert out at wetpool WS elevation det,,,tion d,.sign ws wetpool depth 8' max. Recirculation recommended for depth> 6'. Top of berm or baffle level and at wetpool design elevation (flow exits first cell over berm) or as noted. Note: Berm slope maybe 2:1 when top of berm submerged l' below WQ design W.S. per detention facility requirements Emergent vegetation required for wetpool depths 3' or less. SECTIONA·A NTS fence required for interior side slopes steeper than 3(H) : 1 (V) access road Invert 6" min~. ~~~~:-'~-::~:;;:::~:::::::::::1l capacity of outlet system per detention facility requirements below top of intemal ""''''''~~!Eii berm. Lower placement is desirable. gravity drain if grade allows) 8" min. diameter valve----' Note: See detention facility requi rements for location, interior & exterior sideslopes, and setback requirements. 1124/2005 type 2 catch basin w/sump SECTION B·B NTS 6·100 exterior berms designed per dam safety requirements if applicable 2005 Surface \Vater Design Manual Flow Frequency Analysis LogPearson III Coefficients Time Series File: 15min. tsf Mean= 0.425 StdDev~ 0.164 Project Location:Sea-Tac Skew~ 1. 482 Annual Peak Flow Rates--------Flow Frequency Analysis------- Flow Rate Rank Time of Peak --Peaks Rank Return Prob CFS) (CFS) Period 3.70 9 2/16/49 17: 45 11.14 1 89.50 0.989 5.08 4 3/03/50 15:00 6.17 2 32.13 0.969 2.17 35 8/27/51 18:00 5.51 3 19.58 0.949 2.50 28 10/17/51 7:15 5.08 4 14 .08 0.929 1. 83 43 9/30/53 3:00 5.01 5 10.99 0.909 2.11 38 12/19/53 17:30 4.24 6 9.01 0.889 1. 77 46 7/30/55 21: 15 3.82 7 7.64 0.869 2.66 20 10/04/55 10:00 3.73 8 6.63 0.849 2.55 25 12/09/56 12:45 3.70 9 5.86 0.829 2.36 33 1/16/58 10:00 3.13 10 5.24 0.809 2.97 14 10/18/58 19: 45 3.08 11 4.75 0.789 2.98 13 10/10/59 22:00 3.01 12 4.34 0.769 2.56 22 2/14/61 20:15 2.98 13 3.99 0.749 2.14 36 8/04/62 13: 15 2.97 14 3.70 0.729 2.08 39 12/01/62 20:15 2.87 15 3.44 0.709 1. 63 49 6/05/64 15:00 2.80 16 3.22 0.690 2.40 30 4/20/65 19:30 2.76 17 3.03 0.670 1. 64 48 1/05/66 15:00 2.72 18 2.85 0.650 2.72 18 11/13/66 17: 45 2.69 19 2.70 0.630 5.51 3 8/24/68 15:00 2.66 20 2.56 0.610 2.45 29 10/20/68 12:00 2.65 21 2.44 0.590 1. 50 50 1/13/70 20:45 2.56 22 2.32 0.570 1. 82 44 12/06/70 7:00 2.56 23 2.22 0.550 3.82 7 12/08/71 17:15 2.55 24 2.13 0.530 2.13 37 4/18/73 9:30 2.55 25 2.04 0.510 2.55 24 11/28/73 8:00 2.55 26 1. 96 0.490 2.76 17 8/17/75 23:00 2.54 27 1. 89 0.470 1. 8 9 42 10/29/75 7:00 2.50 28 1. 82 0.450 1. 74 47 8/23/77 14: 30 2.45 29 1. 75 0.430 3.08 11 9/17/78 1:00 2.40 30 1. 70 0.410 4.24 6 9/08/79 13: 45 2.39 31 1. 64 0.390 3.01 12 12/14/79 20:00 2.36 32 1. 59 0.370 2.87 15 9/21/81 8:00 2.36 33 1. 54 0.350 6.17 2 10/05/81 22:15 2.25 34 1. 49 0.330 2.55 26 10/28/82 16:00 2.17 35 1. 45 0.310 1. 98 40 1/02/84 23:30 2.14 36 1. 41 0.291 1. 81 45 6/06/85 21: 15 2.13 37 1. 37 0.271 2.69 19 10/27/85 10:45 2.11 38 1. 33 0.251 3.13 10 10/25/86 22:45 2.08 39 1. 30 0.231 2.54 27 5/13/88 17:30 1. 98 40 1. 27 0.211 2.36 32 8/21/89 16:00 1. 97 41 1. 24 0.191 3.73 8 1/09/90 5:30 1. 89 42 1. 21 0.171 2.56 23 4/03/91 20:15 1. 83 43 1.18 0.151 1. 97 41 1/27/92 15:00 1. 82 44 1.15 0.131 2.39 31 6/09/93 12:15 1. 81 45 1.12 0.111 2.25 34 11/17/93 16:45 1.77 46 1.10 0.091 2.65 21 6/05/95 17:00 1. 74 47 1. 08 0.071 2.80 16 7/19/96 19:30 1. 64 48 1. 05 0.051 11.14 1 12/29/96 11: 45 1. 63 49 1. 03 0.031 5.01 5 10/04/97 14: 15 1. 50 50 1. 01 0.011 Computed Peaks 9.34 100.00 0.990 Computed Peaks 7.49 50.00 0.980 Computed Pea ks 5.99 25.00 0.960 Computed Peaks 4.41 10.00 0.900 computed Peaks Computed Peaks Computed Peaks Computed Peaks 4.15 3.46 2.43 1. 99 8.00 5.00 2.00 1. 30 0.875 0.800 0.500 0.231 Conveyance System Analysis and Design The proposed Jessie Glen stormwater conveyance system consists of a network of catch basins and underground pipes 12, 15, 18 and 24 inch diameter that collect stormwater runoff from the roadway surface and lots, and convey the runoff to the combined wetpond and detention stormwater facility. The stormwater drainage conveyance system has been sized to convey the 25 year design storm event and to contain the 100 year design storm event As directed by King County, the conveyance analysis for the 25 year peak flow has been calculated using the Rational Method and the backwater analysis was completed using the KCRTS software. The existing 12 inch diameter culvert at the intersection of 120th Avenue SE with Road A will be removed and replaced with the pipe segment between catch basins #28 and #29 shown on Figure 3. The capacity of the 12 inch diameter culvert has been calculated to be 2.94 cfs. The pipe system between catch basins 29 to #31 has been sized to convey the culvert flow and the 100 year stormwater flow from the detention pond. The conveyance and backwater calculations are attached following this section. CONVEYANCE CALCULATIONS Job No. 1166-001-005 JESSIE GLEN CATCH BASIN DRAINAGE BASINS PROJECT DATE Drainage Basin 1 Road Impervious Area Jessie Glen September 12, 2005 Total Proposed Drainage Basin 1 Area Drainage Basin 2 Till Grass Area Lot Impervious Area Road Impervious Area Total Impervious Area Total Proposed Drainage Basin 2 Area Drainage Basin 3 Till Grass Area Lot Impervious Area Road Impervious Area Total Impervious Area Total Proposed Drainage Basin 3 Area Drainage Basin 4 Till Forest Area Till Grass Area Lot Impervious Area Road Impervious Area Open Space Impervious Area Total Impervious Area Total Proposed Drainage Basin 4 Area Drainage Basin 5 Till Grass Area Lot Impervious Area Road Impervious Area Total Impervious Area Total Proposed Drainage Basin 5 Area 2904.87 It> = 2904.87 ft' = 14188.67 ft' = 14064.00 ft' = 8524.12 ft' = 22588.12 ft' = 36776.79 It' = 7126.02 ft' = 7032.00 ft' = 4142.06 ft' = 11174.06 ft' = 1830008 ft' = 89153.68 ft' = 10635.11 ft' = 7032.00 ft' = 3664.15 ft' = 927.18ft' = 11623.33 It' = 111412.12 It' = 2874.18 ft' = 2344.00 ft' = 587.22 ft' = 2931.22 ft' = 5805.40 ft' = 0.07 acres 0.07 acres 0.33 acres 0.32 acres 0.20 acres 0.52 acres 0.84 acres 0.16 acres 0.16 acres 0.10 acres 0.26 acres 0.42 acres 2.05 acres 0.24 acres 0.16 acres 0.08 acres 0.02 acres 0.27 acres 2.56 acres 0.07 acres 0.05 acres 0.01 acres 0.07 acres 0.13 acres IIEsm8IengrIESM-JOBSI 11661001 1005IworksI2005-08-04 KCRTSlkcrtsan.xls 1 Job No. 1166-001-005 JESSIE GLEN CATCH BASIN DRAINAGE BASINS PROJECT DATE Drainage Basin 6 Road Impervious Area Jessie Glen September 12, 2005 Total Proposed Drainage Basin 6 Area Drainage Basin 7 Road Impervious Area Total Proposed Drainage Basin 7 Area Drainage Basin 8 Till Grass Area Lot Impervious Area Road Impervious Area Total Impervious Area Total Proposed Drainage Basin 8 Area Drainage Basin 9 Till Forest Area Till Grass Area Lot Impervious Area Road Impervious Area Total Impervious Area Total Proposed Drainage Basin 9 Area Drainage Basin 10 Till Grass Area Open Space Impervious Area Total Proposed Drainage Basin 10 Area 219.10 Ie = 219.10 ft' = 1590.75 ft' = 1590.75 ft' = 6442.27 ft' = 7032.00 ft' = 1440.15 ft' = 8472.15 ft' = 14914.42 ft' = 39415.82 ft' = 7707.73 ft' = 4688.00 ft' = 3750.70 ft' = 8438.70 ft' = 55562.25 ft' = 10884.66 ft' = 4890.21 ft' = 15774.87 ft' = 0.01 acres 0.01 acres 0.04 acres 0.04 acres 0.15 acres 0.16 acres 0.03 acres 0.19 acres 0.34 acres 0.90 acres 0.18 acres 0.11 acres 0.09 acres 0.19 acres 1.28 acres 0.25 acres 0,11 acres 0.36 acres IIEsm8IengrIESM-JOBSI 1166100 11005IworksI2005-08-04 KCRTSlkcrtsan.xls 2 Job No. 1166-001-005 JESSIE GLEN CATCH BASIN DRAINAGE BASINS PROJECT DATE Drainage Basin 11 Till Grass Area Lot Impervious Area Road Impervious Area Total Impervious Area Jessie Glen February 14, 2006 Total Proposed Drainage Basin 11 Area Drainage Basin 12 Till Grass Area Lot Impervious Area Road Impervious Area Total Impervious Area Total Proposed Drainage Basin 12 Area Drainage Basin 13 Till Grass Area Lot Impervious Area Road Impervious Area Total Impervious Area Total Proposed Drainage Basin 13 Area Drainage Basin 14 Till Grass Area Lot Impervious Area Road Impervious Area Total Impervious Area Total Proposed Drainage Basin 14 Area Drainage Basin 15 Till Grass Area Lot Impervious Area Road Impervious Area Total Impervious Area Total Proposed Drainage Basin 15 Area 14127.14ft' = 7032.00 ft' = 4065.52 ft' = 11097.52 ft' = 25224.67 ft' = 4557.90 ft' = 7032.00 ft' = 1587.13 ft' = 8619.13 ft' = 13177.03 ft' = 2675.25 ft' = 2344.00 ft' = 914.45 ft' = 3258.45 ft' = 5933.70 ft' = 7305.23 ft' = 11720.00 ft' = 3347.91 ft' = 15067.91 ft' = 22373.14 ft' = 10340.25 ft' = 14064.00 ft' = 4243.58 ft' = 18307.58 ft' = 28647.82 ft' = 0.32 acres 0.16 acres 0.09 acres 0.25 acres 0.58 acres 0.10 acres 0.16 acres 0.04 acres 0.20 acres 0.30 acres 0.06 acres 0.05 acres 0.02 acres 0.07 acres 0.14 acres 0.17 acres 0.27 acres 0.08 acres 0.35 acres 0.51 acres 0.24 acres 0.32 acres 0.10 acres 0.42 acres 0.66 acres IIEsm8IengrIESM-JOBSI 116610011005IworksI2005-08-04 KCRTSlkcrtsan.xls 3 Job No. 1166-001-005 JESSIE GLEN CATCH BASIN DRAINAGE BASINS PROJECT DATE Drainage Basin 16 Till Grass Area Lot Impervious Area Road Impervious Area Total Impervious Area Jessie Glen February 14, 2006 Total Proposed Drainage Basin 16 Area Drainage Basin 17 Till Grass Area Lot Impervious Area Road Impervious Area Total Impervious Area Total Proposed Drainage Basin 17 Area Drainage Basin 18 Road Impervious Area Total Proposed Drainage Basin 18 Area Drainage Basin 19A Till Grass Area Lot Impervious Area Total Proposed Drainage Basin 17 Area Drainage Basin 19 Road Impervious Area Total Proposed Drainage Basin 19 Area Drainage Basin 20 Till Grass Area Lot Impervious Area Road Impervious Area Total Impervious Area Total Proposed Drainage Basin 20 Area 6630.86 It' = 7032.00 It' = 1742.90 fI' = 8774.90 It' = 15405.76 It' = 2454.93 It' = 2344.00 fI' = 1269.26 It' = 3613.26 It' = 6068.19 fI' = 747.51 It' = 747.51 It' = 9216.25 fI' = 9376.00 It' = 18592.25 It' = 1325.92 It' = 1325.92 It' = 4368.03 It' = 4688.00 It' = 2038.66 It' = 6726.66 It' = 11094.69 It' = 0.15 acres 0.16 acres 0.04 acres 0.20 acres 0.35 acres 0.06 acres 0.05 acres 0.03 acres 0.08 acres 0.14 acres 0.02 acres 0.02 acres 0.21 acres 0.22 acres 0.43 acres 0.03 acres 0.03 acres 0.10 acres 0.11 acres 0.05 acres 0.15 acres 0.25 acres IIEsm8IengrIESM-JOBSI 11661001 1005IworksI2005-08-04 KCRTSlkcrtsan .xls 4 Job No. 1166-001-005 JESSIE GLEN CATCH BASIN DRAINAGE BASINS PROJECT DATE Drainage Basin 21 Till Grass Area Lot Impervious Area Road Impervious Area Total Impervious Area Jessie Glen February 14, 2006 Total Proposed Drainage Basin 21 Area Drainage Basin 22 Road Impervious Area Total Proposed Drainage Basin 22 Area Drainage Basin 23 Road Impervious Area Total Proposed Drainage Basin 23 Area Drainage Basin 24 Till Grass Area Road Impervious Area Total Proposed Drainage Basin 24 Area Drainage Basin 25 Till Grass Area Road Impervious Area Total Proposed Drainage Basin 25 Area Drainage Basin 26 Road Impervious Area Total Proposed Drainage Basin 26 Area 7363.87 re = 7032.00 re = 4426.39 ft' = 11458.39 re = 18822.27 ft' = 795.27 ft' = 795.27 ft2 = 1092.53 ft' = 1092.53 ft' = 113.01 ft' = 1822.86 ft' = 1935.87 ft' = 1488.38 ft' = 6381.12 ft' = 7869.49 ft' = 5404.31 ft' = 5404.31 ft' = 0.17 acres 0.16 acres 0.10 acres 0.26 acres 0.43 acres 0.02 acres 0.02 acres 0.03 acres 0.03 acres 0.00 acres 0.04 acres 0.04 acres 0.03 acres 0.15 acres 0.18 acres 0.12 acres 0.12 acres IIEsm8IengrIESM-JOBSI 1166100 11005IworksI2005-08-04 KCRTSlkcrtsan .xls 5 Job No. 1166-001-005 JESSIE GLEN CATCH BASIN DRAINAGE BASINS PROJECT DATE Drainage Basin 29 Road Impervious Area Jessie Glen February 14, 2006 Total Proposed Drainage Basin 21 Area Drainage Basin 30 Till Grass Area Lot Impervious Area Road Impervious Area Total Impervious Area Total Proposed Drainage Basin 21 Area 2696.38 ft' = 2696.38 ft' = 43107.10 ft' = 4000.00 ft' = 5767.50 ft' = 9767.50 fe = 52874.60 ft' = 0.06 acres 0.06 acres 0.99 acres 0.09 acres 0.13 acres 0.22 acres 1.21 acres IIEsm8IengrIESM-JOBSI 11661001 1005IworksI2005-08-04 KCRTSlkcrtsan .xls 6 STORM SEWER DESIGN CALCULATIONS (by Rational Method) PROJECT: Jessie Glen DATE: September 12, 2005 Runoff Coefficients "c" Values for the Rational Method Till Forest Area 0.15 Till Grass Area Road Impervious Area Lot Impervious Area 0.25 0.90 0.90 Coefficients for the Rational Method" i R" Equation 25-year Design Storm a R 2.66 25-year Design Storm b R 0.65 1OO-year Design Storm a R 1OO-year Design Storm b R 25-year Precipitation PR tOO-year Precipitation PR 25-year i R tOO-year i R 25-year Intensity tOO-year Intensity Paved Area kR 2.61 0.63 3.40 3.90 0.80 0.82 2.73 3.14 20.00 Louupen Drainage 100-year IRoadSpaceDrainageSubbasinCompositeTimeof25-year Till Forest Till Grass Impervious Impervious Subbasin Area Runoff Concentration, Q=CIA Q=CIA Pipe Area (fe) Area (ft') Area (ft') Area (ft') Area (ft') (acres) Coefficient, C, T,(min) (cIs) (cIs) CB#25-CB#24 0.00 1488.38 6381,12 0.00 7869.49 0.18 0.78 6,30 0.38 0.44 CB#24-CB#23 0.00 113.01 1822.86 0.00 1935.87 0.04 0.86 6.30 0.49 0.56 CB#23-CB#22 0.00 0.00 1092.53 000 1092.53 0.03 0.90 6.30 0.55 0.63 CB#22-CB#20 0.00 0.00 795.27 0.00 795.27 0.02 0.90 6.30 0.60 0.68 CB#21-CB#20 0.00 7363.87 4426.39 7032.00 18822.27 0.43 0.65 6.30 0.76 0.87 CB#20-CB#19A 0.00 4368.03 2038.66 4688.00 11094.69 0.25 0.64 6.30 1.81 2.07 CB#19A-CB#19 0.00 9216.25 0.00 9376.00 18592.25 0.43 0.58 6.30 2.48 2,85 CB#19-CB#17 0.00 0.00 1325.92 0.00 1325.92 0.03 0.90 6.30 2.56 2.93 CB#18-CB#17 0.00 0.00 747.51 0.00 747.51 0.02 0.90 6.30 0.04 0.05, CB#17-CB#14 0.00 2454.93 1269.26 2344.00 6068.19 0.14 0.64 6.30 2.84 3.26 CB#16-CB#15 0.00 6630.86 1742.90 7032.00 15405.76 0.35 0.62 6.30 0.60 0.69 CB#15-CB#14 0.00 10340.25 4243.58 14064.00 28647.82 0.66 0.67 6.30 1.80 2,06 CB#14-CB#12 0.00 7305.23 3347.91 11720.00 22373.14 0.51 0.69 6.30 5.60 6.43 CB#13-CB#12 0.00 2675.25 914.45 2344.00 5933.70 0.14 0.61 6.30 0.23 0.26 CB#12-CB#11 0.00 4557.90 1587.13 7032.00 13177.03 0.30 0.68 6.30 6.39 7.33 CB#11-CB#10 0.00 14127.14 4065.52 7032.00 25224.67 0.58 0.54 6.30 7.24 8.30 CB#10-CB#4 0.00 10884.66 0.00 4890.21 15774.87 0.36 0.45 6.30 7.68 8.81 CB#8-CB#7 0.00 6442.27 1440.15 7032.00 14914.42 0.34 0.62 6.30 0.58 0.66 CB#7-CB#6 0.00 0.00 1590.75 0.00 1590.75 0.04 0.90 6.30 0.67 0.77 CB#6-CB#5 0.00 0.00 219.10 0.00 219.10 0.01 0.90 6.30 0.68 0.78 CB#9-CB#5 39415.82 7707.73 3750.70 4688.00 55562.25 1.28 0.28 6.30 0.97 1.11 CB#5-CB#4 0.00 2874.18 587.22 2344.00 5805.40 0.13 0.58 6.30 1.86 2.13 CB#4-CB#3 89153.68 10635.11 3664.15 7959.18 111412.12 2.56 0.24 6.30 11.21 12.85 CB#3-CB#2 0.00 7126.02 4142.06 7032.00 18300.08 0.42 0.65 6.30 11.95 13.71 CB#2-CB#1 0.00 14188.67 8524.12 14064.00 36776.79 0.84 0.65 6.30 13.45 15.43 CB#26-CB#1 0.00 0.00 5404.31 0.00 5404.31 0.12 0.90 6.30 0.31 0.35 CB#l-POND 0.00 0.00 2904.87 0.00 2904.87 0.07 0.90 6.30 13.92 15.96 Ditch Inlet -CB#27 Flow from Existing Culvert -1.01 CB#27-CB#29 1.01 CB#28-CB#29 100 year 15 minute Flow from Detention Pond = 9.34 CB#29-CB#30 0.00 0.00 2696.38 0.00 2696.38 0.06 0.90 6.30 10.50 10.52 CB#30-CB#31-43107.10 5767.50 4000.00 52874.60 1.21 0.37 6.30 11.75 11.93 .- Conservative assumptions were used for establishing the existing areas Velocity Pipe Wet @25-year 25 year % Pipe Diameter Area Perimeter Hydraulic Capacity Capacity 100 year % Pipe Diameter (in) (ft) (ft') (ft) Radius (ft) Slope (ft/ft) Pipe n Capacity (cts) (ft/sec) (cis) Capacity (cIs) CB#25-CB#24 12 1.00 0.7854 3.1416 0.2500 0.0507 0.013 8.04 10.24 4.77% 5.47%, CB#24-CB#23 12 1.00 0.7854 3.1416 0.2500 0.0240 0.013 5.53 7.05 8.83% 10.13%1 CB#23-CB#22 12 1.00 0.7854 3.1416 0.2500 0.0216 0.013 5.25 6.68 10.48% 12.02% CB#22-CB#20 12 1.00 0.7854 3.1416 0.2500 0.0051 0.013 2.55 3.25 23.33% 26.76% CB#21-CB#20 12 1.00 0.7854 3.1416 0.2500 0.0050 0.013 2.53 3.22 30.20% 34.64% CB#20-CB#19A 12 1.00 0.7854 3.1416 0.2500 0.0050 0.013 2.53 3.22 71.51% 82.03% CB#1 9A-CB#1 9 12 1.00 0.7854 3.1416 0.2500 0.0050 0.013 2.53 3.22 98.20% 112.65% CB#19-CB#17 12 1.00 0.7854 3.1416 0.2500 0.0050 0.013 2.53 3.22 101.17% 116.05%, CB#18-CB#17 12 1.00 0.7854 3.1416 0.2500 0.0200 0.013 5.05 6.43 0.84% 0.96% CB#17 -CB#14 12 1.00 0.7854 3.1416 0.2500 0.0235 0.013 5.48 6.97 51.87% 59.49% CB#16-CB#15 12 1.00 0.7854 3.1416 0.2500 0.0052 0.013 2.58 3.28 23.28% 26.70% CB#15-CB#14 12 1.00 0.7854 3.1416 0.2500 0.0050 0.013 2.53 3.22 71.10% 81.56% CB#14-CB#12 15 1.25 1.2272 3.9270 0.3125 0.0080 0.013 5.79 4.72 96.70% 110.92% CB#13-CB#12 12 1.00 0.7854 3.1416 0.2500 0.0113 0.013 3.80 4.84 5.95% 6.83% CB#12-CB#11 18 1.50 1.7671 4.7124 0.3750 0.0066 0.013 8.56 4.84 74.64% 85.62% CB#11-CB#10 18 1.50 1.7671 4.7124 0.3750 0.0160 0.013 13.32 7.54 54.31% 62.29% CB#10-CB#4 18 1.50 1.7671 4.7124 0.3750 0.0098 0.013 10.43 5.90 73.68% 84.51% CB#8-CB#7 12 1.00 0.7854 3.1416 0.2500 0.0050 0.013 2.53 3.22 22.95% 26.32% CB#7-CB#6 12 1.00 0.7854 3.1416 0.2500 0.0050 0.013 2.53 3.22 26.50% 30.40% CB#6-CB#5 12 1.00 0.7854 3.1416 0.2500 0.0051 0.013 2.55 3.25 26.73% 30.66% CB#9-CB#5 12 1.00 0.7854 3.1416 0.2500 0.0583 0.013 8.63 10.98 11.23% 12.88% CB#5-CB#4 12 1.00 0.7854 3.1416 0.2500 0.0050 0.013 2.53 3.22 73.68% 84.52%, CB#4-CB#3 24 2.00 3.1416 6.2832 0.5000 0.0080 0.013 20.29 6.46 55.23% 63.36% CB#3-CB#2 24 2.00 3.1416 6.2832 0.5000 0.0133 0.013 26.16 8.33 45.68% 52.40% CB#2-CB#1 24 2.00 3.1416 6.2832 0.5000 0.0170 0.013 29.58 9.41 45.47% 52.16% CB#26-CB#1 12 1.00 0.7854 3.1416 0.2500 0.0168 0.013 4.63 5.90 6.59% 7.56% CB#1-POND 24 2.00 3.1416 6.2832 0.5000 0.0224 0.013 33.95 10.81 40.99% 47.02% Ditch Inlet -CB#27 12 1.00 0.7854 3.1416 0.2500 0.2000 0.013 15.98 20.34 6.32% 6.32% CB#27-CB#29 12 1.00 0.7854 3.1416 0.2500 0.0195 0.013 4.99 6.35 20.25% 20.25% CB#28-CB#29 18 1.50 1.7671 4.7124 0.3750 0.0101 0.013 10.59 5.99 88.24% 88.24% CB#29-CB#30 18 1.50 1.7671 4.7124 0.3750 0.0109 0.013 11.00 6.22 95.71% 95.71 % CB#30-CB#31 19 1.58 1.9689 4.9742 0.3958 0.0112 0.013 12.88 6.54 92.68% 92.68% Solve For: Discharge Culvert Summary Allowable HW Elevation Computed Headwater Elevation Inlet Control HW Elev Culvert Calculator Report Existing Culvert Flow Calculation 503.75 ft Headwater Depth! Height 503.75 It Discharge 503.67 It Tailwater Elevation 0.70 1.01 cfs 0.00 It Outlet Control HW Elev 503.75 It Control Type Outlet Control Grades Upstream Invert 503.05 It Downstream Invert Length 22.00 ft Constructed Slope Hydraulic Profile Profile M2 Depth, Downstream Slope Type Mild Nannal Depth Flow Regime Subcritical Critical Depth Velocity Downstream 3.20 ftls Critical Slope Section Section Shape Circular Mannings CoeffiCient Section Material CMP Span Section Size 12 inch Rise Number Sections 1 Outlet Control Properties Outlet Control HW Elev 503.75 ft Upstream Velocity Head Ke 0.90 Entrance Loss Inlet Control Properties Inlet Control HW Elev 503.67 ft Flow Control Inlet Type Projecting Area Full K 0.03400 HDS 5 Chart M 1.50000 HDS 5 Scale C 0.05530 Equation Fonn y 0.54000 Project Title: Jessie Glen Existing Culvert along 120th Ave_ SE i:\, .. \001\005\works\2005-08-04 kcrts\existcul.cvm ESM, Inc. 502.74 ft 0.014091 ftllt 0.42 ft 0.46 ft 0.42 It 0.019817 ftlft 0.024 1.00 ft 1.00 ft 0.12 ft 0.11 ft Un submerged 0.8 ft' 2 3 Project Engineer: Laura Cociasu CulvertMaster v1.0 09/28/05 11 :32:08 AM © Haestad Methods, Inc 37 Brookside Road Waterbury, CT 06708 (203) 755-1666 Page 1 of 1 KING COUNTY BACKWATER CALCULATIONS Rational Method Calculated Flow: Catch Basin Drainage Basins Rational Method 1DO-year Q Ratio Overflow (cfs) Drainage Basin 1 0.19 0.012 Drainage Basin 2 1.72 0.108 Drainage Basin 3 0.85 0.053 Drainage Basin 4 1.91 0.119 Drainage Basin 5 0.26 0.016 Drainage Basin 6 0.Q1 0.001 Drainage Basin 7 0.10 0.006 Drainage Basin 8 0.66 0.042 Drainage Basin 9 1.11 0.070 Drainage Basin 10 0.51 0.032 Drainage Basin 11 0.97 0.061 Drainage Basin 12 0.64 0.040 Drainage Basin 13 0.26 0.016 Drainage Basin 14 1.11 0.069 Drainage Basin 15 1.37 0.086 Drainage Basin 16 0.69 0.043 Drainage Basin 17 0.28 0.017 Drainage Basin 18 0.05 0.003 Drainage Basin 1 9 0.09 0.005 Drainage Basin 19A 0.77 0.048 Drainage Basin 20 0.51 0.032 Drainage Basin 21 0.87 0.055 Drainage Basin 22 0.05 0.003 Drainage Basin 23 0.07 0.004 Drainage Basin 24 0.12 0.008 Drainage Basin 25 0.44 0.028 Drainage Basin 26 0.35 0.022 Total Conveyance Flow to Pond 15.98 1.000 Drainage Basin 27 1.01 0.084636 Drainage Basin 28 9.34 0.782676 Drainage Basin 29 0.17 0.01464 Orainaqe Basin 30 1.41 0.118048 Total Conveyance Flow from ~ond 11.93 1.000 BACKWATER CALCULATIONS SHEET 2 3 4 5 6 7 8 9 10 11 Barrel 25-year 100·year Pipe Pipe Hydraulic Outlet Inlet Barrel Barrel Velocity Pipe Segment Q=CIA Q~CIA Length Diameter Radius Elevation Elevation Area Velocity Head Tailwater Friction Pipe Run C8 to C8 (ds) (cfs) (ft) (in) (ft) Pipe n (ft) (ft) (ff) «(Vs) (ft) Elevation (ft Loss N1 POND-C8#1 13.92 15.96 45.00 24 0.500 0.013 494.25 495.26 3.14 5.08 0.40 501.75 0.22 N2 C8#1-C8#2 13.45 15.43 116.00 24 0.500 0.013 495.26 497.23 3.14 4.91 0.37 502.71 0.54 N3 C8#2-C8#3 11.95 13.71 159.00 24 0.500 0.013 497.23 499.35 3.14 4.36 0.30 503.52 0.58 N4 C8#3-C8#4 11.21 12.85 134.00 24 0.500 0.013 499.35 500.42 3.14 4.09 0.26 504.29 0.43 N5 C8#4-C8#10 7.68 8.81 182.00 18 0.375 0.013 500.92 502.71 1.77 4.99 0.39 505.30 1.27 N6 C8#10-CB#11 7.24 8.30 121.00 18 0.375 0.013 502.71 504.65 1.77 4.70 0.34 506.98 0.75 N7 CB#11-CB#12 6.39 7.33 98.00 18 0.375 0.013 504.65 505.30 1.77 4.15 0.27 508.12 0.47 N8 CB#12-CB#14 5.60 6.43 88.00 15 0.313 0.013 505.63 506.33 1.23 5.24 0.43 508.76 0.86 N9 CB#14-CB#17 2.84 3.26 186.00 12 0.250 0.013 506.58 510.96 0.79 4.15 0.27 509.89 1.54 N10 CB#17-CB#19 2.56 2.93 43.00 12 0.250 0.013 510.96 511.23 0.79 3.73 0.22 512.05 0.29 N10A CB#19-CB#19A 2.48 2.85 40.00 12 0.250 0.013 511.23 511.43 0.79 3.62 0.20 512.74 0.25 N11 CB#19A-CB#20 1.81 2.07 74.00 12 0.250 0.013 511.43 511.80 0.79 2.64 0.11 513.41 0.25 N12 CB#20-CB#22 0.60 0.68 37.00 12 0.250 0.013 511.80 511.99 0.79 0.87 0.01 513.76 0.01 N13 CB#22-CB#23 0.55 0.63 40.00 12 0.250 0.013 511.99 512.85 0.79 0.80 0.01 513.79 0.01 N14 CB#23-CB#24 0.49 0.56 57.00 12 0.250 0.013 512.85 514.22 0.79 0.71 0.01 513.82 0.01 N15 CB#24-CB#25 0.38 0.44 33.00 12 0.250 0.013 514.22 515.91 0.79 0.56 0.00 514.52 0.00 N16 CB#1-CB#26 0.31 0.35 217.00 12 0.250 0.013 496.26 499.91 0.79 0.45 0.00 502.71 0.02 N17 CB#4-CB#5 1.86 2.13 115.00 12 0.250 0.013 501.42 501.99 0.79 2.72 0.11 505.30 0.41 N18 CB#5-CB#6 0.68 0.78 41.00 12 0.250 0.013 501.99 502.20 0.79 1.00 0.02 505.84 0.02 N19 CB#6-CB#7 0.67 0.77 88.00 12 0.250 0.013 502.20 502.63 0.79 0.98 0.01 505.87 0.04 N20 CB#7-CB#8 0.58 0.66 23.00 12 0.250 0.013 502.63 502.75 0.79 0.85 0.01 505.95 0.01 N21 CB#14 CB#15 1.80 2.06 57.00 12 0.250 0.013 506.58 506.87 0.79 2.62 0.11 509.89 0.19 N22 CB#15-CB#16 0.60 0.69 23.00 12 0.250 0.013 506.87 506.99 0.79 0.88 0.01 510.35 0.01 N23 CB#5-CB#9 0.97 1.11 23.00 12 0.250 0.013 501.99 503.33 0.79 1.41 0.03 505.84 0.02 N24 CB#12-CB#13 0.23 0.26 24.00 12 0.250 0.013 505.88 506.15 0.79 0.33 0.00 508.76 0.00 N25 CB#17-CB#18 0.04 0.05 24.00 12 0.250 0.013 510.96 511.44 0.79 0.06 0.00 512.05 0.00 N26 CB#20-CB#21 0.76 0.87 24.00 12 0.250 0.013 511.80 511.92 0.79 1.11 0.02 513.76 0.01 N27 CB#31-CB#30 11.75 11.93 19.00 18 0.375 0.013 492.12 492.33 1.77 6.75 0.71 493.62 0.24 N28 CB#30-CB#29 10.50 10.52 289.00 18 0.375 0.013 492.33 495.48 1.77 5.96 0.55 494.90 2.88 N29 CB#29-CB#28 9.34 9.34 25.00 18 0.375 0.013 495.48 496.25 1.77 5.29 0.43 498.19 0.20 N30 CB#29-CB#27 1.01 1.01 156.00 12 0.250 0.013 495.98 499.00 0.79 1.29 0.03 499.92 0.12 Assumed full flow in existing pipe system along 192nd Street BACKWATER CALCULATIONS SHEET 12 13 14 15 16 17 18 19 20 Pipe Run Pipe Segment Entrance I Entrance I Exit I Outlet I Inlet I Q/AD L Q Ratio 1 Appr. ~ Bend ~ Junction ~ HW ~ Upstream ~ CB Grate N1 POND-CB#1 501.97 0.20 0.40 502.57 497.61 3.59 0.00 0.40 0.54 0.00 502.71 504.78 2.07 N2 CB#1-CB#2 503.25 0.19 0.37 503.81 498.99 3.47 0.11 0.37 0.00 0.09 503.52 503.50 -0.02 N3 CB#2-CB#3 504.10 0.15 0.30 504.55 500.89 3.09 0.05 0.30 0.00 0.04 504.29 504.87 0.58 N4 CB#3-CB#4 504.72 0.13 0.26 505.11 501.93 2.89 0.12 0.26 0.35 0.10 505.30 505.93 0.63 N5 CB#4-CB#10 506.57 0.19 0.39 507.15 504.70 4.07 0.03 0.39 0.19 0.03 506.98 507.33 0.35 N6 CB#10-CB#11 507.73 0.17 0.34 508.24 506.52 3.83 0.06 0.34 0.17 0.05 508.12 509.30 1.18 N7 CB#11-CB#12 508.60 0.13 0.27 509.00 506.61 3.38 0.04 0.27 0.00 0.03 508.76 510.24 1.48 N8 CB#12-CB#14 509.63 0.21 0.43 510.26 508.25 4.68 0.07 0.43 0.00 0.06 509.89 511.19 1.30 N9 CB#14-CB#17 511.43 0.13 0.27 511.84 512.30 4.15 0.02 0.27 0.00 0.01 512.05 515.32 3.27 N10 CB#17-CB#19 512.34 0.11 0.22 512.66 512.45 3.73 0.01 0.22 0.29 0.00 512.74 516.34 3.60 N10A CB#19-CB#19A 513.00 0.10 0.20 513.30 512.62 3.62 0.05 0.20 0.28 0.04 513.41 516.21 2.80 N11 CB#19A-CB#20 513.66 0.05 0.11 513.82 512.54 2.64 0.03 0.11 0.02 0.03 513.76 515.57 1.81 N12 CB#20-CB#22 513.77 0.01 0.01 513.79 512.30 0.87 0.00 0.01 0.01 0.00 513.79 515.89 2.10 N13 CB#22-CB#23 513.81 0.01 0.01 513.82 513.15 0.80 0.00 0.01 0.00 0.00 513.82 516.87 3.05 N14 CB#23-CB#24 513.83 0.00 0.01 513.84 514.52 0.71 0.01 0.01 0.00 0.01 514.52 518.38 3.86 N15 CB#24-CB#25 514.53 0.00 0.00 514.53 516.19 0.56 0.03 0.00 0.00 0.02 516.21 519.79 3.58 N16 CB#1-CB#26 502.73 0.00 0.00 502.74 500.21 0.45 0.03 0.00 0.00 0.03 502.76 503.90 1.14 N17 CB#4-CB#5 505.71 0.06 0.11 505.88 502.70 2.72 0.02 0.11 0.06 0.01 505.84 507.33 1.49 N18 CB#5-CB#6 505.86 0.01 0.02 505.88 502.51 1.00 0.00 0.02 0.01 0.00 505.87 507.33 1.46 N19 CB#6-CB#7 505.91 0.01 0.01 505.93 502.94 0.98 0.01 0.01 0.02 0.01 505.95 506.74 0.79 N20 CB#7-CB#8 505.95 0.01 0.01 505.97 503.06 0.85 0.04 0.01 0.00 0.03 505.99 506.74 0.75 N21 CB#14-CB#15 510.08 0.05 0.11 510.24 507.57 2.62 0.09 0.11 0.14 0.07 510.35 510.56 0.21 N22 CB#15-CB#16 510.36 0.01 0.01 510.38 507.30 0.88 0.04 0.01 0.00 0.04 510.40 510.56 0.16 N23 CB#5-CB#9 505.86 0.02 0.03 505.90 503.76 1.41 0.07 0.03 0.00 0.06 505.93 507.33 1.40 N24 CB#12-CB#13 508.76 0.00 0.00 508.77 506.45 0.33 0.02 0.00 0.00 0.01 508.78 510.24 1.46 N25 CB#17 -CB#18 512.05 0.00 0.00 512.05 511.73 0.06 0.00 0.00 0.00 0.00 512.05 515.32 3.27 N26 CB#20-CB#21 513.77 0.01 0.02 513.80 512.24 1.11 0.05 0.02 0.00 0.05 513.83 515.57 1.74 -- N27 CB#31-CB#30 493.86 0.35 0.71 494.93 495.14 5.51 1.41 0.71 0.00 0.68 494.90 495.97 1.07 N28 CB#30-CB#29 497.77 0.28 0.55 498.60 497.89 4.86 0.17 0.55 0.00 0.14 498.19 502.20 4.01 N29 CB#29-CB#28 498.38 0.22 0.43 499.03 498.34 4.32 9.34 0.43 0.00 1.32 499.92 503.65 3.73 N30 CB#29-CB#27 500.04 0.01 0.03 500.08 499.73 1.29 1.01 0.03 0.00 0.56 500.61 503.14 2.53 6 i i 1 i f. 510 500 490 A PORTION OF THE S,W. 1/4 OF SECTION 33, TOWNSHIP 23 NORTH, RANGE 5 EAST, W.M. n C.2, J]'-.LL. Hr., 'SoD. c L ......... , 9 lNST~L 7.5')(12' RIP-RAP PAD, 28 DEEP S.D. r+A r+B ROAD A -"hi-, "_" __ _ EE SHED RD~O~ ---- 1!B_,-- CELL #2 DETENTION .••••.•.••.•• POND BOTTOM EL. = 492.50 r\1";',;';~'" we --1 • ,'~ S"'" "-02 " '::::==-____ " . £ 1 '------' -----. '-. : ,-,-//,,/ . ~, ../' ~ _. __ 0 ~o :00 0 c J-, 0 _.£ ~ 6' BERt.! A 2: 1 POND SIDE PER GEOTECH" / DETENTION POND SCALE: 1"_20' 4. 4.B STORAGE VOLUI,IES (CUBIC FEU) PROVIDED I /JS CONSTRUCTED R/_ r!,· ,,"'" I· ' n --- EMERGENCY OVEl'1FLOW SPILLWAY ELEVATION 502.14 DETENTION 97.1 I' CF WATER OUAllfy-I 26,163 cr I J3,04:5 CF 1:S'"" ,"0"'0 100-1R .. 2~-HR. W.S. EL ~ 501.75 FENCE 1 .. 5' ACCESS RQAO rf5' "" 12 L.r •• o S~8 .. D:r.; 18"",i S D. J \ 1, l' SEDIl,!ENT STORAGE ' 17 BOTTOi,! or POND EL. -491.25 CELL #1 30+60 31 +00 31+40 ITOP Of" w.o. STORAGI; EL. 496.25 BOTTOY or POND EL. "" 492.50 CELL #2 31+80 32+20 SECTION C-C SCALE' I-~ 20' ~O~ll 1-. S' \Il:RT 18 SEDIYENT STORAGE 32+60 W 25 L.r .. o S .. 1.00:; 19 Ill' S.D, Ie.s. 129. TYP 1.C. ;. 503.03 I.E. 496.50. I.E. = 496.00. 3JNI!lf Sl"(!JcfURf lll PER DtTAIL SHEO OT-02 T.G. -50L75 I.E. ~ 496.25. la-Ill 33+00 8"". 7' ' .. 33+40 510 500 490 D:lSTit'lG DITCH ELEVATION = 500.89 1 .. 1 c J EROSION CONTROL SEED MIX FOR POND SLOPES PORTIONS PERCENT PERCENT -~ £ l.!B!Ir ~ REOTOP (Agro"" o.!h) ,~ 92 90 AN"IU"'l RYE (Loll"", "",Ili.,lbrtanJ 4~ 98 90 CKE_CS FESCUE (""1"",, nd\,.." rom"'ull1I~) 40ll: " " " " WHilE DUTCH ClOV£R rrn.joIium. nlP""'J lOll: 510 500 5i 490 HORIZONT"l OATUI>I; .... A$HINGTON STATE PLANE COORDINATES. NORTH ZONE, "lAD '8J/'91, BASED ON TIES TO KING COUNTY PUBLISHED CONTROl. NC'lT 10 SCAL-E VERTiCAl DATUr.4· NAVD '88, BENCH MARK _ 4" :(4· CONCRETE r.40"lUI>IENT WITH LEAD AND lACK IN CASE LOCATED AT THE INTERSECTlQI.j or S£ I92NO ST AND 116 AVE SE. ELEVATION _ 514.98 rEET. SCALE~20' CONTOUR1'"NTEi\VAL _ 2' I' I rENCE EMERGENCY;OVERrLOW SPILLWAY ELEVATION 5i:J2.14 f E~ •. 'STING GROUND ---". . ---"",-- j 2 . -if! 1' \= f=,\~'H'=O-'~' ~,,~. ~.~. ~~".'" ,I I' .... , ~R.WSE . L..~501.75~- W.O: STORAGE EL.= 496.25 I' SEOIIdENl STORAGE nOM or POND EL.-'491.2 C.B. 'I. :TYP[ 2-48""111 fb' \A p~Pkcis6g-; .u. '" 504.78 : 1 : !ggt ;~:: 10+60 w 510 500 490 20+60 WI 'SOLID LOCKING LID T.G. = 50 •. 60 I.E. z 494.99. Ie". CELL #1 11+00 11 +40 SECTION A-A f"ENCE SCALE' ,-.. ZO' HORIZ . 1-~ 5' '/EIlT . 11+80 W rENCE 1 r--] rl.lrRGENCY· DVf.:Rf"LOW SPILLWAY ELEVATION 502. U W.S. EL. K 50t.75 1, fTOP Or W.D. STORAGE 496.25 BOTTOM or p ~92.5- CELL #2 21+00 21+40 SECTION 8-8 SCALE: ,:m 2~' IlORll 1_~y(R1. fj 21+80 KING COUNTY D.D.E.S. 510 500 490 510 500 490 CALL 48 HOURS BEFORE YOU DIG 1-800-424-5555 Jl""";". £"-1~~ So-niotE~" • .,.. Compl~"", [}(ll. 00l5Dt"0 -., Apj:l,o",,' [}(ll~ ~~O~"Es:t'~R~i!&~' Com""'M" EVI"SIONS 1'''''''' jiin.u IV2iII I~ ~H a wl$ m ·f I o J J jJ CJ Z o J o I jJ D.. -, i i::l~ ~ i~ i , , E "fI o .... ;:; f 0 E • • • i. .~ t .~~ z W l C9 W U) U) W J Wo z III Z o ;= u W III I z a. o z o a. z o z w W o 1= z J o U o 00'-00' DWG ...... ,,~ ptl-Ol D~SIC"'[O flY cc;(: DR ........ !Iv JL.c CHEC><ED BY I ::~' 0' n"200~ PRI ... T: PD·01 1 0 D~ 18 $H(05 Special Reports and Studies Pacific Geo Engineering, LLG. has prepared a geotechnical report dated September 19, 2005 for the Jessie Glen project site. This report was reviewed and considered in preparation of this drainage report and a copy has been provided herein for reference. Pacific Geo Engineering, LLC. has also prepared a pavement design report dated February 6, 2006 and a copy is provided following the geotechnical report GEOTECHNICAL ENGINEERING STUDY For JESSIE GLEN PRELIMINARY PLAT 116TH AVENUE SE & 120TH AVENUE SE RENTON, KING COUNTY, WASHINGTON Prepared For JPS HOLDING, LLC 18124 RIVIERA PLACE SW SEATTLE, WA 98166 Prepared By Pacific Geo Engineering, LLC 831 177TH PL SW LYNNWOOD, W ASHlNGTON 98037 PGE PROJECT NUMBER 050996 September 19, 2005 September 19,2005 JPS HOLDING, LLC 18124 RIviera Place SW Seattle, Washington 98166 Attn.: Mr. Joe Singh Re: Dear Mr. Smgh: Geotechnical Engineering Study Proposed Jessie Glen Preliminary Plat 116th Avenue SE and 120th Avenue SE Renton, King County, WaShington PGE Project No. 050996 As per the request of Laura Cociasu of ESM, Pacific Geo Engineering, LLC (PGE) has completed a geotechnical engineering study at the proposed development to be located at Renton. The purpose of this study was to determine the groundwater table, pond berm slope, and the pavement sections. This study was accomplished in general accordance with our proposal No. 58144, dated September 1,2005, and was granted to proceed by written authorization of Mr. Joe Singh, on September 8,2005. Site Location & Descriptions The general location of the site is shown on the Vicinity Map, Figure I. The project site is located WIthin a region dominated by residences. The site is currently vacant and covered with scattered to dense small to large trees, bushes, and shrubs. Based on our visual observations, in general, the site is relatively level with minor undulations across the site. Field Investigation We explored the surface and subsurface conditions at the project site on September 8, 2005. Six 6) test pits were excavated to depths of about 5 to 13 feet below the existing grades, three (3) of which were excavated at the proposed storm pond area to depths of about 13 feet below the existing grades. The lest pits were completed usmg a backhoe provided by a subcontractor. The specific number, locations, and depths of the test pits were selected in relation to the existing and proposed site features, 831177th PL SW. Lynnwood. WA. 98037 (Tel) 425-918-1428. (Fax) 425-918-1401 Jessie Glen Preliminary Plat 116th & 120th Avenue SE ProJect No. 050996 September 19,2005 Page 2 of8 Pacific Geo Engineering, LLC Geotechnical Engineering Consultation & Inspection accessibility, underground utility conflicts, purpose of evaluation, and budget considerations. The proposed locations of the test pits were estimated by measuring from existing site features and should be considered accurate only to the degree implied by the method used. The approximate test pit locations are shown on the Site & Exploration Plan, Figure 2. A professional geotechnical engineer from our firm observed the excavations, continually logged the subsurface conditions in each test pit, collected representative bulk samples from different soil layers, and observed pertinent site features. Samples were designated according to the test pit number and depth, stored in watertight plastic containers. The samples that were not used for laboratory testing will be retained for 30 days from the date of submission of this report. Further storage or transfer of samples can be made at the client's expense upon written request. Results of the field investigation are presented on the test pit logs, which are presented on Pages A-I through A-3 of Appendix A. The final logs are modified based on the interpretation of our field logs, laboratory test results, and visual examination of the samples in the laboratory. Laboratory Testing The bulk samples were visually classified in the field and laboratory, and later on supplemented by grain size analysis to evaluate the general physical properties and engineering characteristics of the soils encountered. Sieve analysis was performed on one selected sample in accordance with the ASTM 0-422 and 0-2487 procedures. The result of the sieve analysis with the uses classifications of the soil is presented on the grain-size distribution graph (Figure B-1) enclosed in Appendix B. Engineering Evaluation The results from the field and laboratory tests were evaluated and engineering analyses were performed to provide pertinent information and recommendations on the following geotechnical aspects of the proposed site development: o Soil and groundwater conditions of the site. o Detention pond berm slope. o Asphalt pavement thickness. Jessie Glen Preliminary Plat J J6th & J 20th A venue SE Project No. 050996 September J 9,2005 Page 3 of 8 Soil & Groundwater Conditions Pacific Geo Engineering, He Geotechnical Enaineering Consultation & Inspection Based on the results of our field explorations, we believe that glacial till exists at shallow depths across the entire site with weathered silty sandy gravelly soils over it. The average thickness of the topsoil was found to be about 12 inches, which was composed of light brown silt with roots and organics. The topsoil was underlain by weathered brown silty sandy gravelly soils, which continued upto 2.5 feet below the existing grades. This deposit was then underlain by gray glacial tills consisted of silty sandy gravel. The till was occasionally cemented. This deposit was continued upto the bottom of the test pits. In general, the weathered soils were medium dense and moist in condition, whereas the tills were very dense and slightly moist in conditIOn. The preceding discussion on the subsurface conditions of the site is intended as a general review to highlight the major subsurface stratification features and material characteristics. For more complete and specific information at individual test pit locations, please review the Test Pit Logs (Pages A-I through A-3) included in Appendix A. These logs include soil descriptions, stratification, and location of the samples and laboratory test data. It should be noted that the stratification lines shown on the individual logs represent the approximate boundaries between various soil strata; actual transitions may be more gradual or more severe. The subsurface conditions depicted in the logs are for the test pit locations indicated only, and it should not necessarily be expected that these conditions are representative at other locations of the site. Neither groundwater nor seepage or mottling was encountered in the test pits within their tennination depths. It is to be noted that seasonal fluctuations in the groundwater elevations and the presence of perched water in the upper weathered soils may be expected in the amount of rainfall, surface runoff, and other factors not apparent at the time of our exploration. Typically, the groundwater levels rise higher and the seepage flow rates increase during the wet winter months in the Puget Sound area. The possibility of groundwater level fluctuations and the presence of perched water must be considered when designing and developing the proposed pond at this site. Jessie Glen Preliminary Plat 116th & 120th Avenue SE Project No. 050996 September 19,2005 Page 4 of8 Engineering Recommendations Pond Berm Slopes Pacific Geo Engineering, HC Geotechnical Engineering Consultation & Insoection Based on the nature of the soils in this site the pond berms could be laid on 2H: I V slopes. Clearing and Grubbing Initial site preparation for construction of paved areas should include stripping of vegetation and topsoils from the site. Based on the topsoil thickness encountered at our test pit locations, we anticipate topsoil stripping depths of about 12 inches, however, thicker layers of topsoil may be present in unexplored portions of the site. Stripped vegetation debris should be removed from the site. Stripped organic topsoils will not be suitable for use as structural fill but may be used for future landscaping purposes. Sub grade Preparation After the site clearing and site stripping, cut and fill operations can be initiated to establish desired pavement grades. Any exposed sub grades that are intended to provide direct support for the pavement andlor require new fills should be adequately proofrolled to evaluate their conditions. Proofrolling should be done with a loaded dump truck or front-end loader under the supervision of a geotechnical engineer from PGE, andlor must be probed with aT-probe by the geotechnical engineer to identify the presence of any isolated soft and yielding areas and to verify that stable subgrades are achieved to support the pavements. If any subgrade area ruts and pumps excessively and cannot be stabilized in place by compaction, the affected soils should be over-excavated completely to firm and unyielding suitable bearing materials, and replaced with new structural fills to desired final subgrade levels, If the depth of overexcavation to remove unstable soils becomes excessive, a geotextile fabric, such as Mirafi 500X or equivalent in conjunction with granular structural fills may be considered. Such decision should be made on-site by a geotechnical engineer from PGE during the actual construction of the project. Reuse of On-Site Soils The on-site near surface weathered soils contain fines of approximately 12%. Due to such fines content, this material is considered moderately sensitive to changes in moisture content and therefore, may be adversely affected by wet weather conditions. A detailed discussion on this issue is provided latter on in this report. However, this soil may be considered suitable for use as structural fills during the dry weather periods. Jessie Glen Preliminary Plat 116th & 120th Avenue SE Project No. 050996 September 19,2005 Page 5 of8 Structural Fill Pacific Geo Engineering, LLC Geotechnical Engineering Consultation & Inspection Structural fill is defined as non-organic soil, free of deleterious materials, and well-graded and free-drainmg granular material, with a maximum of 5 percent passing the No. 200 sieve by weight, and not exceeding 6 inches for any individual particle. A typical gradation for structural fill is presented in the following table. Structural Fill U.S. Standard Sieve Size Percent Passing by Dry Weight 3 inch 100 inch 50 -100 No.4 25 -65 No. 10 10 -50 No. 40 0-20 No. 200 5 Maximum' Other materials may be suitable for use as structural fill provided these are approved by a geotechnical engineer from PGE. Such materials typically include clean, well-graded sand and gravel pit-run); clean sand; various mixtures of gravel; crushed rock; controlled-density-fill (CDF); and lean- mix concrete. Recycled concrete derived from crushed parent material is also useful for structural fill provided this material is thoroughly crushed to a size deemed appropriate by the geotechnical engineer usually less than 2 inches). The top 12 inches of compacted structural fill and all underlying fill should havc a maximum 3-inch particle diameter unless specifically approved by a geotechnical engineer from PGE. Fill Placement and Compaction Requirements Structural fills under the pavement sub grades should be placed in uniform loose lifts not exceeding 12 inches in thickness, and compacted to a minimum of 95% of the soil's laboratory maximum dry density as determined by ASTM Test Designation D-1557 (Modified Proctor) method, to produce a firm and unYlelding surface. The fi'lls should be moisture conditioned such that its final moisture content at the time of compaction should be within about 2 percent of its optimum moisture content, as determined by this ASTM method. If field density tests indicate that the last lift of compacted fills has not been achieved the required percent of compaction or the surface is pumping and weaving under loading, then the fills should be Jessie Glen Preliminary Plat I I 6th & 120th Avenue SE Project No. 050996 September 19,2005 Page 6 of 8 Pacific Geo Engineering. LLC Geotechnical Engineering Consultation & Inspection scarified, moisture-conditioned to near optimum moisture content, re-compacted, and re-tested prior to placing additional lifts. Wet Weather Construction Due to the moderate fines content in the near surface weathered soils this soil should be considered moisture sensitive when wet. During wet weather periods, typically between October and May, increases in the moisture content of this soil can cause significant reduction in the soils strength and support capabilities. In addition, this soil when become wet may be slow to dry and thus significantly retard the progress of grading and compaction activities. It will, therefore, be advantageous to perform the earthwork construction activities in this site during the dry season, typically between July and September, so that earthwork costs can be significantly reduced over wet weather construction. The earth contractor must use reasonable care during site preparation and excavation so that the subgrade soils are remain firm, unyielding, and stable, particularly during wet weather conditions. If the construction takes place during the wet weather, and should the near surface weathered soils become wet and disturbed, and cannot be adequately compacted it may be necessary to adopt some remedial measures to enhance the subgrade conditions in this site. The contractor should include a contingency in the earthwork budget for this possibility. The appropriate remedial measure be best determined by PGE during the actual construction of the project. In the event earthwork takes place during the wet season, we recommend that special precautionary measurements should be adopted to minimize the impact of water and construction acltvities on the moisture sensitive soils. It is recommended that earthwork be progressed part by part in small sections to minimize the soil's exposure to wet weather. Traversing of construction equipment can cause considerable disturbance to the exposed subgrades, therefore, should be restricted within the specific drive areas. This will also prevent excessive widespread disturbance of the subgrades. Construction of a new working surface from an advancing working surface could be used to avoid trafficking the exposed subgrade soils. Any excavations or removal of unsuitable soils should be immediately followed by the placement of backfill or pavement. At the end of each day, no loose on-site soils and exposed subgrades be left uncompacted or properly tamped, which will help seal the subgrade and thereby to minimize the potential for moisture infiltration into the underlying layers of fills or subgrades. Pavement Thickness All pavement sub grades be prepared as described above. Depending on the final grading plan, we assume that the pavement subgrades should either be comprised of adequately proofrolled competent undisturbed native soil, or be comprised of a minimum of one foot of granular structural fill that is compacted adequately. Jessie Glen Preliminary Plat 116th & 120th Avenue SE Project No. 050996 September 19, 2005 Page 7 of 8 Pacific Geo Engineering, LLC Geotechnical Engineering Consultation & Inspection We assumed that the traffic would mostly consist of passenger cars, which is typical for a residential community. Two types of pavement sections may be considered for such traffic, the minimum thickness of which are as follows: 2 mches of Asphalt Concrete (AC) over 2 inches of Crushed Surface Top Course (CSTC) over a 6 inches of Granular Subbase, or 2 inches of Asphalt Concrete (AC) over 4 inches of Asphalt Treated Base (A TB) materiaL The 1998 Standard Specifications for Washington State Department of Transportation (WSDOT) and American Public Works Association (APW A) should be applicable to our recommendations that aggregate for AC should meet the Class-B grading requirements as per WSDOT Standard Specifications 9-03.8(6). For the CSTC, we recommend using imported, clean, crushed rock, per WSDOT Standard Specifications 9-03.9(3). For the untreated base course (CRB), we recommend using Bank run per WSDOT Standard Specifications 9-03,19, For the ATB, the aggregate should be consistent with WSDOT Standard Specifications 9-03.6 (2), For the granular subbase course, we recommend using imported, clean, well-graded sand and gravel, such as Ballast or Gravel Borrow per WSDOT Standard Specifications 9-03.9(1) and 9-03.14, respectively, Long-term performance of the pavement will depend on its surface drainage. A poorly-drained pavement section will deteriorate faster due to the infiltration of the surface water into the subgrade soils and thereby reducing their supporting capability, Therefore, we recommend that using a minimum surfacing drainage gradient of about 1 % to minimize this problem and to enhance the pavement performance. Also, regular maintenance of the pavement be considered by sealing surface cracks that may occur during the life of the pavement Report Limitations The recommendations submitted in this report are based on the information available from ESM, and the subsurface informatIOn available from this study. If there are any revisions to the plans for this project or if traffic volume assumed for such development changes or if deviations from the subsurface conditions noted in this geotechnical report are encountered during construction, PGE should be notified IITunediately to determine if changes in the pavement recommendations are required, If PGE is not notified of such changes, PGE will not be responsible for the impact of those changes on the project The geotechnical engineer warrants that the assumptions, recommendations, specifications, or professional advice contained herein have been made in accordance with the generally accepted professional geotechnical engineer practices in the local area, No other warranties are implied or expressed. Jessie Glen Preliminary Plat I 16th & 120th Avenue SE Project No. 050996 September 19,2005 Page 8 of 8 Pacific Geo Engineering, LLe Geotechnical Engineering Consultation & Inspection ThIS report has been prepared for the exclusive use of JPS Holding, and their design consultants for the specific application to the proposed development in Renton, Washington. We appreciate the opportunity to perform this geotechnical study and look forward to continued participation during the design and construction phase of this project. If you have any questions pertaining to this report, or if we may be of further service, please do not hesitate to call us at 425-918- 1428 or 425-218-9316. Respectfully submitted, Pacific Geo Engineering, LLC Santanu Mowar, MSCE, P.E. Principal Attachments: Figure I Figure 2 Appendix A Appendix B Vicinity Map Site & Exploration Plan Soil Test Pit Logs Laboratory Test Result D'\GEOTECHNfCALI1005-proj\050996Jessie Glen Rpt lEXPIRES 01 -0I-~(' Project No: 050996 Date: September 19, 200S Drawn by: SM Client: JPS Holding, LLC VICINITY MAP Not to Scale PROJECT Jessie Glen Preliminary Plat 116th Ave SE & 120th Ave SE Renton, Pierce Co., Washington Pacific Geo Enqineerinq,LLc Geotechnical Engineering, Consulting & Inspection Figure No.1 hli ~ ~ #l !O I --II 'If /' """'" ,,,.,,,,,..., , ' </' " ,/ ROAt:\D 1,", "''':''''''''' .'1:.~.". .. ~U " 0 .'/ I _ rr-t' ',,~ 1,6 I T L:~~~~~7L--22 . ~. hrl''--w- R=~~~ ~'I 1/ •. .,' ROAD BI ~ -(suBACCESS) 26 29 30 31 :sr.?" .,.. ~ naa 5' ~ Sf n.:J g IJ 0 j!'J' .' SIGHT DISTANCE 116TH A.VE. Sf... I R!W) B (MINOR NUfRW) DESIGN SI'£El), 4lI IoFH EImJI!IHG SICHf OISTNIC£: 0= f'RO't'IIlED: )020' STOPPN.:i SICKf [IIS1AitIX: REQUIRED: 400' 400' SCALE: 1-_ I"""iw _ .. 5; &,2!W1 }, (NfJGIjOOBHQOO mil ECIOR) I EH1mIIIG SIGHT OIST.o.NCE: 5TOPf'It«) SIOHT ~ -- REOUIftEl): +to" REQUIRED:. ~ F'f«14llD: :><'90" PR!]VI)£D: >~ A ' ~.,,."" "',~' , " LWI" __ . " .' " t' ,! -~:, , ' I • ~I' ,f' " TP-f P3 I ~ <~., "", 37 j-' /'\ 10 '-' ... t- 0° , 4 • 4>' , II- 0 Project No.: 050996 Date: September 19,2005 Drawn By: SM Client: JPS Holding, LLC SITE PLAN & EXPLORATION PLAN Not to Scale PROJECT J essie Preliminary Plat 116th Ave SE & 120th Ave SE Renton, King Co., Washington Pacific Geo Enqineerinq,LLc Geotechnical Engineering, Consulting & Inspection Fignre 2 I Pacific Geo Enqineerinq,LLC Geotechnical Engineering Consultation & Inspection Jessie Glen Preliminary Plat Project No. 050996 Sept. 19.2005 Page A-I SOIL TEST PIT LOGS TEST PIT -1 Date of Excavation: 09/08/05 Depth, Ft. USCS Soil Description Sample No.! Moisture -#200 % Depth, Ft. Content 0/0 0-1 Topsoil: 12" thk. Lt. Brn. Silt wi Roots and Organics I -2.5 GM Weathered Brown Silty Sandy Gravel S1/2 10.5 12.1 Moist, Med. Dense 2.5 -7 SP Gray Silty Sandy Gravel (Glacial Till) S2/6 6.1 S1. Moist, V. Dense V. Hard digging was encountered in this deposit Note: Test pit was terminated at approximately 7 feet below the existing ground surfaces (bgs). No groundwater or seepage was encountered within the exploratory depth. No mottling was noticed within the exploration depth. No caving was noticed within the exploration depth TEST PIT -2 Date of Excavation: 09/08/05 Depth, Ft. USCS Soil Description Sample No.! Moisture -#200 % Depth, Ft. Content % 0-I I Topsoil: 12" thk. Lt Bm. Silt wi Roots and I Organics I -2.S GM Weathered Brown Silty Sandy Gravel Moist, Med. Dense 2.S -5 SP Gray Silty Sandy Gravel (Glacial Till) SI. Moist, V. Dense V. Hard digging was encountered in this deposit Note: Test pit was terminated at approximately 5 feet below the existing ground surfaces (bgs). No groundwater or seepage was encountered within the exploratory depth. No mottling was noticed within the exploration depth. 1'0 caving was noticed within the exploration depth I I Jessie Glen Preliminary Plat Project No. 050996 Sept. 19,2005 Page A-2 i Depth, Ft. uses 0-1 I -2.5 GM 2.5 -13 SP TEST PIT -3 Soil Description Topsoil: 12" thk. Lt. Brn. Silt wi Roots and Organics Weathered Brown Silty Sandy Gravel Moist, Med. Dense Gray Silty Sandy Gravel (Glacial Till) SI. Moist, V. Dense V. Hard digging was encountered in this deposit Pacific Geo Enqineerinq,LLC Geotechnical Engineering Consultation & Inspection Date of Excavation: 09108/05 Sample No.1 Moisture -#200 % Depth, Ft. Content 0/0 SI/2 9.8 S2110 4.2 Note: Test pit was temUnated at approximately 13 feet below the existing ground surfaces (bgs). No groundwater or seepage was encountered vvithin the exploratory depth. No mottling was noticed within the exploration depth. No caving was noticed within the exploration depth TEST PIT -4 Date of Excavation: 09108/05 Depth, Ft. uses Soil Description Sample No.1 Moisture -#200 % Depth, Ft. Content 0/0 0-1 Topsoil: 12" thk. U. Brn. Silt wi Roots and Organics I -2.5 GM Weathered Brown Silty Sandy Gravel Moist, Med. Dense 2.5-12 SP Gray Silty Sandy Gravel (Glacial Till) SI. Moist, V. Dense V. Hard digging was encountered in this deposit Note: Test pit was temUnated at approximately 12 feet below the existing ground surfaces (bgs). No groundwater or seepage was encountered within the exploratory depth. No mottling was noticed within the exploration depth. No caving was noticed within the exploration depth I I I I JeSS1e Glen Preliminary Plat Pcoject No. 050996 Sept. 19,2005 Page A-3 Depth, Ft. uses 0-1 I ~ 2.5 GM 2.5-13 SP Pacific Geo Enqineerinq,LLC Geotechnical Enaineering Consultation & Inspection TEST PIT -5 Date of Excavation: 09/08/05 Soil Description Sample No.! Moisture -#200 % Depth, Ft. Content % Topsoil: 12" thk Lt. Bm. Silt wi Roots and Organics Weathered Brown Silty Sandy Gravel Moist, Med. Dense Gray Silty Sandy Gravel (Glacial Till) SI. Moist, V. Dense V. Hard digging was encountered in this deposit Note: Test pit was temlinated at approximately 13 feet below the existing ground surfaces (bgs). No groundwater or seepage was encountered within the exploratory depth. No mottling was noticed within the exploration depth. No caving was noticed within the exploration depth TEST PIT -6 Date of Excavation: 09108/05 Depth, Ft. uses Soil Description Sample No.! Moisture -#200 % Depth, Ft. Contcnt % O~ I Topsoil: 12" thk. Lt. Bm. Silt wi Roots and Organics I ~ 2.5 GM Weathered Brown Silty Sandy Gravel Moist, Med. Dense 2.5 -5 SP Gray Silty Sandy Gravel (Glacial Till) SI. Moist, V. Dense V. Hard digging was encountered in this deposit Note: Test pit was temlinated at approximately 5 feet below the existing ground surfaces (bgs). No groundwater or seepage was encountered within the exploratory depth. No mottling was noticed within the exploration depth. No caving was noticed within the exploration depth Particle Size Distribution Report 0 , , , , , , ~ s ~ : 0 ~ ~ ;r W 8 ~ ~ < N -" " 100 I ! I II: I : 1 i I ' :' :: I: 90 i H~~-:---~--: I , I' I-. , --, t\ : i I 1 I i ' , I I I 80 --~ , I , , r .~-. -,---+--i : I , , I II I i I i I 70 :! I \ -~ I' i: ! 0:: /: I ..:." , I [ ,'! llJ 60 --~ -----, z i j' " .. _. I LL , I-" 50 -z !: : II I I: ~ .-llJ i I I i U I , I : : 1'1 !' i0:: I' I llJ 40 CL I ' Ii I! I: :\ I 1 II !: I I 1 I' , , i ' ,II , , , , I, I \ . 30 -, I I, 1\ I: " I Ii I , I, I 20 , '" II: I: I I I , I i, I' , ,! i I 10 --,. , ' , , !: , I I I I ' I: , I ' i i i0 , I ' i 500 100 10 1 0,1 0.01 0,001 GRAIN SIZE -mm COBBLES % GRAVEL % SAND % FINES CRS. FINE CRS. MEDIUM I FINE SILT I CLAY 0.0 39.1 I 7.7 3.6 9.9 I 27.6 12.1 SIEVE PERCENT SPEC.' PASS? Soil Oescrigtion SIZE FINER PERCENT (X=NO) Silty gravel with sand 3.0 In. 100.0 2.5 In. 88.5 2 in. 85.1 1.5 In. 70.1 Atterberg Limits I In. 66.8 PL= LL= PI= 3/4 In. 60.9 4 53.2 Coefficients # 10 49.6 085= 50.6 060~ 18.1 050= 2.20 #40 39.7 100 20.2 030= 0.252 015= 0.100 010= 200 12.1 Cu = Cc= Classification uses= GM AASHTO= Remarks no specification provided) Sample No.: S-I Source of Sample: Native Soil Date: 09-08-05 Location: Test Pit -1 Elev.lDepth: 2 feet Client: JPS Holding, LLC Pacific Geo Engineering. LLC Project: Jessie Glen Preliminary Plat Geotechnical Enu/ne.erlng, Consultation & Inspect/on Prolect No: 050996 Plate B-1 PAVEMENT DESIGN For JESSIE GLEN PRELIMINARY PLAT FRONTAGE ROAD IMPROVEMENT 116TH AVENUE SE) RENTON, KING COUNTY, WASHINGTON Prepared For JPS HOLDING, LLC 18124 RIVIERA PLACE SW SEATTLE, WA 98166 Prepared By Pacific Geo Engineering, LLC 831177THPLSW LYNNWOOD, WASHINGTON 98037 PGE PROJECT NUMBER 050996-1 February 6, 2006 February 6, 2006 JPS HOLDING, LLC 18124 Riviera Place SW Seattle, Washington 98166 Attn.: Mr. Joe Singh Re: Pavement Design for 116th Avenue SE Proposed Jessie Glen Preliminary Plat Renton, King County, Washington PGE Project No. 050996-1 Ref: Geotechnical Report (No. 050996) for Jessie Glen Preliminary Plat, prepared by PGE, dated September 19, 2005. Dear Mr. Singh: As per the verbal request of Ms. Laura Cociasu of ESM Consulting Engineering, Pacific Geo Engineering, LLC (PGE) has completed a pavement design for the proposed widening section of the northbound lane of 116th Avenue SE adjacent to the project's west boundary. The location of the site is shown on the Vicinity Map, Figure I and the proposed widening area is shown on Road Improvement Area, Figure 2. The proposed expanded road section will be approximately 13 feet wide. The details of the pavement design calculations are included in Appendix A of this report. 1.0 Subsurface Information The subsurface information used for the pavement design is obtained from the above-referenced geotechnical report prepared previously by PGE. A brief description of the native soil type expected in the road-widening area is provided below. The proposed road improvement area may be underlain by weathered brown silty sandy gravelly soils, followed by shallow glacial till (hardpan) soils. The tills could be expected at approximately 2.5 feet below the existing grades. 831 177th PI. SW • Lynnwood, WA 98037 • (Tel) 425-918-1428 • (Fax) 425-918-1401 Jessie Glen Preliminary Plat Frontage Road Improvement I I 6th Avenue SE Project No. 050996-1 February 6,2006 Page 2 of8 Pacific Geo Engineering, LLC Geotechnical Engineering, Consultation & Inspection It is to be noted that the presence of perched water in the near surface permeable loams just above the till deposit are expected during the wet winter months. Typically, the groundwater levels rise higher and the seepage flow rates increase during the wet winter months in the Puget Sound area. The possibility of presence of perched water must be considered if the proposed road section is built during the wet winter months. It should be noted that the above soil information is available from the test pits that were excavated within the property during PGE's previous geotechnical study. Due to the proximity of these test pits to the proposed road improvement area, it is assumed that similar soil type found in the test pits may also exist in the proposed road improvement area. However, it should be noted that the assumed soils units in the improvement area may contain inclusions of other soil types or may contain entirely different soil types. Therefore, we recommend that the soil information used in this design must be verified during the actual construction of the road. If the actual soil types found different during the constmction than what it is assumed during this design then PGE should be notified immediately of these differences so that necessary amendment to our design provided in this report can be made. 2.0 Pavement Design The pavement section is designed based on the "Layered Design Analysis", as outlined in Section 3.1.5 of Part II, Chapter 3 "Highway Pavement Structural Design", of AASHTO Guide for Design of Pavement Structures 1993". The general pavement design parameters used in this study is based on the guidelines published in the King County Draft Pavement Specifications, available from Mr. Doug Walters of King County Materials Laboratory. These guidelines are utilized in conjunction with the soil information available from the above-referenced geotechnical report. The total traffic volume including the current traffic (Annual Average Daily Traffic (AADT», the truck percentage, and the annual growth factor are available from Mr. Johny Walker of King County Traffic Department. The average daily traffic to be generated from the project is available from Ms. Laura Cociasu of ESM Consulting Engineering. Based on the native sub grade soil type expected in the road widening area, the rood subgrade design parameters are estimated and used in the pavement design. According to the soil descriptions provided above, the soil type for the native subgrade soil may be classified as SILTY GRAVEL with SAND (USCS classification 'GM'). Based on this soil type, a Resilient Modulus (Mr) value of 10,000 psi is estimated from the King County Draft Pavement Specifications. Jessie Glen Preliminary Plat Frontage Road Improvement 116th Avenue SE Project No. 050996-1 February 6, 2006 Page 3 of S Layer Material Parameters Resilient Modulus, psi Drainage Co-efficient Layer Co-efficient Table 1: Design Parameters AC ATB 450,000 250,000 1.0 1.0 0.44 0.34 Pacific Geo Engineering, LLC Geotechnical Engineering, Consultation & Inspection Layers eRB Granular Subbase 30,000 20,000 0.9 0.9 0.14 O.t I Based on the total traffic volume and the pavement design parameters, the design ESAL value and the corresponding structural number for the proposed road improvement are determined, which are presented in the following table. Table 2: Design Parameters Street Name AADT LDF D Truck % Growth Design Single Axle ESAL Design Factor Life Loading Factor ESAL 116thAveSE 6585 1.0 1.0 5.0 1.129 20yr 20,0001b, [.4 3.63 x 10 N-bound Line AADT-Average Daily Traffic (includes current traffic in I 16th and project traffic) LDF -Lane Distribution Factor D -Directional Distribution Factor ESAL -Equivalent Single Axle Loading SN -Structural Number Tota[ SN Required 3.87 Based on the above structural number the thickness of different layers of the pavement is determined using the 'Layered Design Analysis' method. A step-by-step design for determining the layer thickness is presented in Appendix A. The layer thickness for different pavement section options is given below. Jessie Glen Preliminary Plat Frontage Road Improvement 116th Avenue SE Project No. 050996-1 February 6, 2006 Page 4 0[8 Layers Asphaltic Concrete (AC), Class B Asphalt Treated Base (ATB) Crushed Rock Base Course (CRB)/ Crushed Surfacing Top Course (CSTC) Granular Subbase above native subgrade SN Provided SN Required Pacific Geo Engineering, LLC Geotechnical Enalneen"nq Consultation & Insoection Table 3: Pavement Sections Layer Thickness Option A Option B 4 inch 4 inch 8 inch 8 inch - 12 inch - 3.87 3.87 3.96 4.16 We recommend that the pavement thickness shown above should be used for the proposed widening area of I I 6th Avenue SE. The 1998 Standard Specifications for Washington State Department of Transportation (WSDOT) and American Public Works Association (APWA) should be applicable to our recommendations that aggregate for AC should meet the Class-B grading requirements as per WSDOT Standard Specifications 9-03.8(6). For the CSTC, we recommend using imported, clean, crushed rock, per WSDOT Standard Specifications 9-03.9(3). For the untreated base course (CRB), we recommend using Bank run per WSDOT Standard Specifications 9-03.19. For the ATB, the aggregate should be consistent with WSDOT Standard Specifications 9-03.6 (2). For the granular subbase course, we recommend using imported, clean, well-graded sand and gravel, such as Ballast or Gravel Borrow per WSDOT Standard Specifications 9-03.9(1) and 9-03.14, respectively. Long-term performance of the pavement will depend on its surface drainage. A poorly-drained pavement section will deteriorate faster due to the infiltration of the surface water into the subgrade soils and thereby reducing their supporting capability. Therefore, we recommend that using a minimum surfacing drainage gradient of about I % to minimize this problem and to enhance the pavement performance. Also, regular maintenance of the pavement be considered by sealing surface cracks that may occur during the life of the pavement. Jessie Glen Preliminary Plat Frontage Road Improvement 116th Avenue SE Project No. 050996-1 February 6,2006 Page 5 of 8 3.0 Other Recommendations 3.1 Laboratory Tests Pacific Geo Engineering, LLC Geotechnical Engineering Consultation & Inspection It should be noted that our pavement analysis is based on the assumption that the final road subgrade will be consisted of SILTY GRAVEL with SAND (USeS classification 'GM'). Therefore, Sieve Analysis test must be performed on the final road subgrade soils prior to the actual construction of the pavement to confirm that the assumed soil type is correct. 3.2 Sub grade Verification We recommend that a professional geotechnical engineer from PGE must be retained on-site by the owner or the contractor during the construction of the pavement to verify that the final road subgrade is consisted of the native soils that is assumed in the design. In the event, the native soils at the final road subgrades are found different than what is assumed in the design the pavement recommendations provided in this report must be revised to reflect those differences. 3.3 Subgrade Preparation The final pavement subgrades be prepared in accordance with the recommendations described in this section. After the removal of the vegetations from the shoulder areas, cut and fill operations can be initiated to establish the final pavement subgrades. Any exposed subgrades that are intended to provide direct support for new pavements and/or require new fills should be adequately proofrolled and/or must be probed with a T-probe by the project geotechnical engineer to identify the presence of any isolated soft and yielding areas, and to verify that stable subgrades are achieved to support the pavements. Proofrolling should be done with a loaded dump truck or a front-end loader or a steel drum vibratory roller under the supervision of a geotechnical engineer of PGE. If any sub grade area ruts and pumps excessively and cannot be stabilized in place by compaction, the affected soils should be over-excavated completely to firm and unyielding, and suitable bearing materials, and replaced with new structural fills to desired final sub grade levels. 3.4 Structural Fill Structural fill is defined as non-organic soil, free of deleterious materials, and well-graded and free-draining granular material, with a maximum of 5 percent passing the No. 200 sieve by weight, and not exceeding 6 inches for any individual particle. A typical gradation for structural fill is presented in the following table. Jessie Glen Preliminary Plat Frontage Road Improvement 116th Avenue SE Project No. 050996-1 February 6, 2006 Page 60[8 U.S. Standard Sieve Size 3 inch J/4 inch No.4 No. 10 No. 40 No. 200 Pacific Geo Engineering, LLC Geotechnical Engineering Consultation & Inspection Table 4: Structural Fills Percent Passing by Dry Weight 100 50 -100 25 -65 10-50 0-20 5 Maximum>t< Based on the % inch fraction. Other materials may be suitable for use as structural fills provided they are approved by PGE, Such materials typically used include clean, well-graded sand and gravel (pit-run); clean sand; various mixtures of gravel; crushed rock; controlled-density-fill (CDF); and lean-mix concrete. Recycled concrete derived from crushed parent material is also useful for structural fills provided this material is thoroughly crushed to a size deemed appropriate (usually less than 2 inches) by PGE. The top 12 inches of compacted structural fills should have a maximum 3-inch particle diameter and all underlying fills a maximum 4 to 6 inch diameter unless specifically approved by PGE. 3.5 Fill Placement and Compaction Requirements Structural fills should be placed in uniform loose lifts not exceeding 12 inches in thickness for heavy compactors and 4 inches for hand held compaction equipment. Each lift should be compacted to a minimum of 95 percent of the soil's laboratory maximum dry density as determined by ASTM Test Designation D-1557 (Modified Proctor) method, or to the applicable minimum City or County standard, whichever is the more conservative. The fills should be moisture conditioned such that its final moisture content at the time of compaction should be at or near (typically within about 2 percent) of its optimum moisture content, as determined by the ASTM method. If the fill materials are on the wet side of optimum, they can be dried by periodic windrowing and aeration or by intermixing lime or cement powder to absorb excess moisture. If field density tests indicate that the last lift of compacted fills has not been achieved the required percent of compaction or the surface is pumping and weaving under loading, then the fills should be scarified, moisture-conditioned to near optimum moisture content, Te-compacted, and re-tested prior to placing additional lifts. lessie Glen Preliminary Plat Frontage Road Improvement I I 6th Avenue SE Project No. 050996-1 February 6, 2006 Page 7 of8 3.6 Wet Weather Construction Pacific Geo Engineering, HC Geotechnical Engineering, Consultation & Insaection Based on the soil information available from PGE's referenced geotechnical report, the native subgrade soils are expected to be of silty soils containing moderate amount of fines (12.1%). Due to the possibility of containing such amount of fines the native subgrades should be considered moisture sensitive when wet. During wet weather periods, typically between October and May, increases in the moisture content of this soil can cause significant reduction in the soils strength and support capabilities. In addition, this soil when become wet may be slow to dry and thus significantly retard the progress of grading and compaction activities. It will, therefore, be advantageous to perform the earthwork construction activities in this site during the dry season, typically between July and September, so that earthwork costs can be significantly reduced over wet weather construction. The earth contractor must use reasonable care during site preparation and excavation so that the subgrade soils are remain firm, unyielding, and stable, particularly during wet weather conditions. If the construction takes place during the wet weather, and should the near surface silty soil becomes wet and disturbed, and cannot be adequately compacted it may be necessary to adopt some remedial measures to enhance the subgrade conditions in this site. The contractor should include a contingency in the earthwork budget for this possibility. The appropriate remedial measure be best determined by PGE during the actual construction of the project. In the event earthwork takes place during the wet season, we recommend that special precautionary measurements should be adopted to minimize the impact of water and construction activities on the moisture sensitive soils. It is recommended that earthwork be progressed part by part in small sections to minimize the soil's exposure to wet weather. Traversing of construction equipment can cause considerable disturbance to the exposed subgrades, therefore, should be restricted within the specific drive areas. This will also prevent excessive widespread disturbance of the subgrades. Construction of a new working surface from an advancing working surface could be used to avoid trafficking the exposed subgrade soils. Any excavations or removal of unsuitable soils should be immediately followed by the placement of backfill or pavement. At the end of each day, no loose on-site soils and exposed subgrades be left uncompacted or properly tamped, which wiII help seal the subgrade and thereby to minimize the potential for moisture infiltration into the underlying layers of fills or subgrades. Jessie Glen Preliminary Plat Frontage Road Improvement 116th Avenue SE Project No. 050996-1 February 6, 2006 Page 8 of 8 Report Limitations Pacific Geo Engineering, LLC Geotechnical Engineering Consultation & Inspection The recommendations submitted in this report are based on the information available from POE's geotechnical report, ESM's project plan, and King County's traffic count. Ifthere are any revisions to the plan for this project or if traffic volume information changes or if deviations from the subsurface conditions noted in the PGE's referenced geotechnical report are encountered during the construction, PGE should be notified immediately of those changes and deviations to determine if corresponding changes in the pavement recommendations are required. If PGE is not notified of such changes and deviations, PGE will not be responsible for the impact of those changes and deviations on the project. PGE makes no responsibility regarding the accuracy of the information available from other consultant and sources, based on which, the pavement design was performed. The geotechnical engineer warrants that the assumptions, recommendations, specifications, or professional advice contained herein have been made in accordance with the generally accepted professional geotechnical engineer practices in the local area. No other warranties are implied or expressed. This report has been prepared for the exclusive use of IPS Holding, and their design consultants for the specific application to the proposed improvement area of 116th Avenue SE in Renton, Washington. We appreciate the opportunity to perform this geotechnical study and look forward to continued participation during the construction phase of this project. If you have any questions pertaining to this report, or if we may be of further service, please do not hesitate to call us at 425-918-1428 or 425-218- 9316. Respectfully submitted, Pacific Geo Engineering, LLC Santanu Mowar, MSCE, P.E. Principal Attachments: Figure 1 Figure 2 Appendix A Vicinity Map Road Improvement Area Pavement Design Calculations D:\GEOTEC HN ICA L \2006-proj\050996-1 pavement design IEXPIRES O{-Ol-2008 Project No: 050996-1 Date: February 6, 2006 Drawn by: SM Client: JPS Holding VICINITY MAP Not to Scale PROJECT Jessie Glen Preliminary Plat Frontage Road Improvement 116th Avenue SE Reuton, King County, Washington Pacific Geo Enqineerinq,LLc Geotechnical Engineering, COnsulting & Inspection Figure 1 n,~· ,C-cE) '1/" .' "'~"<w ,,,.,. '-U "V' _. l ____ l IIA.. _, ~A." 7 " . 15 ;~I'] I (' ~ !:--F~' 1'\-' .",,' ~"~. ,=,r. '11 21 ~ I ~ P 8 14" 7 ~ _.,-22 I f~~ ) ~~ 0" • "'. ~~ • I J~ ~.~~. 1\. .... \ ~. • • 1: 'f::.. .~~ ~ko:~i.~ . be c~ c SIGHT DISTANCE U6TH A'iE. __ .5E I RQN) 8 (MINOR AlUfRtAJ) D[5IGN SPUD: 4S YPti T "l~v~ .~ ~.~ ', A .1,,),9j ~~ J..2~ .].3) 1-~.J)l'y '''. 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'L,,,,t ,~.". .' \ I ! . :-'-~b -''0' ttit=. h'n -t,;.. -~--'; ~-+f-1 sue,ccEss:'!?;F TA '/ • 7, _. "\.' ~. /' ,.' I ~I~ J !oj! f--_____ b ' 0 ..... .,. J' ~ ,'-1/ / Ii _ '--' -~ ~, .~ r" '~6 'Y ~. ~ ~ ~ 1 ". ~. -r ' -'" ~ I ........ ' f'-.J 1 \-_. --~ ./' L ,-~ AACTO ~?5'~ <oJ " -~ l1E ~Ul -38 ::39:; ::4 -42 -43 ::44 -4 ::46 ~47:: ~@~ ~~ l ... rP "" ~,,~!oj " . ! ,,~,7. .~.~,;. g. • ~~ "' •• ~T" "7' ~1i';; ~"( ::::: • , ••• , • 0 ~ ---. .' I ~ t ~,:? ,--, l1! ~, 1----...... , Il ! :;;~ .. , >t..,. _ , II '" \! :C:/ / ~v .....,. , ... or ,. r ..... ~ /--\. iI, . ROAD IMPROVEMENT AREA j~if I # . ~ .' "! o Ill" ~ I~ z ~ I~ I; ~~ w PROJECTProjectNo,: 050996-1 Pacific Geo Enqineerinq.LLcDate: February 6, 2006 Drawn By: SM Client: JPS Holding Jessie Glen Preliminary Plat Frontage Road Improvement 116th Avenue SE Renton, Kim' I'mmtv, Wa.hin!Jton Geotechnical Engineerlngr Consulting & Inspection Figure 2 PAVEMENT J:JESIGN I> HATIVE SOIL TY PE AT ROFlb SUBGRADE: SoiL Il!CSCRIPl1DN = usc s SOIL-CLASS. ;:::. GM NAnVF- ASSUME» 3) TRAFFIC. VOLUME IlbitlAVE SE ~6'21'55 vpd.(1'1-86Ut--Ib LAH:) 313':;' \lpJ {§ -BoO U ",]) LM-IE) A ~ Pc c ~ "T .,.,., ~ E P ~o ~ E C T -n-II S L. AN E SINCE-N-80UND LANE ~S ~:r. ~" ,~ '" .,..." ROAIl TiPE TWO-Lf\,JE D = !·o L/'I',IE ""J:.IS-rR1S1JT\O" FAC' ,< ,D f<, L ~ "I ·0 T -5 -j. TI' IJ C)<. .). ESIG"J LIFE. r = 20 -yRS ~ GPo ," TIl r'= fleTO f< G ~ 1 . I 2. '3 1· 4 DESIGN ESAL = 6235;< 6·051< )-4)< 300 X a·o:",y 1·4 1·12'3 ;< I' 0 ')< I ·0 X 20:>' 3'; 5 Project No: 050996-1 Date: February 6, 2006 Drawn by: SM 3,£2.5 ,'75G ~ 3·63 '1-16 PROJECT Jessie Glen Preliminary Plat Frontage Road Improvement 116th Avenue SE Pacif~c Geo Enqineerinq,LLC Geotechnical Engineering, Consulting & Inspection Client: JPS Holding Renton, King County, Washington I Design Sheet No. 1/+ 5) Pf\'fEMENT J:;>ESIGN PAl'''' r'lETF P5 PEL-l 11. 13lLI:':" , F' = 85 '/. C,vE f' A I. L S -! p. tJ:-I) ,.,. f<-)) 'J) ~V\ All 0 t'J , So ~ 0·50 rNIT1AL SfO PVICE'" \3lLl T'I , "p( ~ -4,6 TEI'-VIINP,'L-SERVI eEl' Bll-IT,! rt " 2·5 , E5\G., 5E-Pv I CEP,8ILI T 'I L05S, t> PS I : \·5 t 1-A 'f r=c R-eo, EFF, * A SS v f.l\S)) MR \}"LV E S 4)RAINJOGE LA'lE P ::tlRAIHfiG f;. L-I','f E R G ., tv1 R \j AI-UE" I J>E-5CP1P11ONS CO-fFF-, ('me) co-EFf, C>..l.) (ps L) , 1 Ac \.0 i 0·44 -4 so, tS0D j , II AlB [,0 0' 30 1 250,000 i i ---I CRIJSH EJ) I , 0'9 0·14 30, (jOc) i ! RoC 1"-8 ~s E CP-B) i i , , i I GR~NNUL-I\R I 20, uTO f--:' i 0-1\ , I I i I SUBBASE I I INAll'lE -IOj 000 5UBG i1 A1lE 1 -I ----- 1 Project No: 050996-1 PROJECT Date: February 6, 2006 Jessie Glen Preliminary Plat Pacific Geo Engineering,LLc Drawn by: SM Frontage Road Improvement Geotechmcal Engineering, Consulting & Inspection 116th Avenue SE Client: JPS Holding Renton, King County, Washington Design Sheet No. 21 + o PilON '" 5A'I SN St~1 2· 49 PC'(').])· SN2- I $ 1'13j I -! - 2·93 - GRA",NULI\i"- SUBBflSE 3.87 MflTIV., I _____ -l __ . __ . ___ --'-___ -ks_u_B_G..:f_~_J;> ___ Ei___l q TK f'--A c. 0.44:><4 =t·7~ 2·-19 3·5 Ii S N 3 -5 r-l : -5 \'1,") I (IA 3 Of' " ') 0. B7 _ I. DO ~ _ , . 76) / @.. 0 x o· II) = 1\'/, '5 A'-f I 'Z." 'll-\)< - J.g i" a·ll.>" I ~ r 0]0('3 "D3 = 5 t l 3 = y. - t-5N2 TOTfl 1.-SN P!,OV II> roD = SN, 1'76 + I' 00 a I AC. = 4 C. RB ;: 2; " GPANNU1.IIR. Su8B1'5E. = 1'2. Project No: 050996 1 Date: February 6, 2006 Drawn by: SM Client: JPS Holding PROJECT J essie Glen Preliminary Plat Frontage Road Improvement 116th Avenue SE Reuton, King County, Washington II 1 • 1 '? t-S N] I' 1 ':l = 3'3(; >3.87~ 5 D '" 1-<' Pacific G~o .Enqineerinq,LLc Geotechmcal Engmeermg, Consulting & Inspection Design Sheet No.3 / + oPll ~"I B 5N 'RESIn· l-A'fERS I S N I I 5N'2.. 1·7b -/ITS I IN"VEI -I 3· 87 5u BGl" f\DI'" I SA"' 4 f\C TilTlH .. SN Project No: 050996·1 Date: February 6, 2006 Drawn by: SM Client: JPS Holding pp-ov I:DE:D ATB = PROJECT J essie Glen Preliminary Plat Frontage Road Improvement 116th A venue SE Renton, King County, Washington 2·+ Pacif~c Geo .Enqineerinq,LLC Geotechnical Engmeermg, Consulting .& Inspection Design Sheet No. 4-/+ 7 Other Permits A Stormwater Pollution Prevention Plan (SWPPP) has been prepared. It is not expected at this time that the Jessie Glen project will require any other state or federal permits (i.e. Hydraulic Project Approval, Short-Term Water Quality Modification Approval, a Dam Safety Permi~ Section 10 Permit or Section 404 Permit). The project also will not require onsite sewage disposal or any new well permits. CSWPP Analysis and Design The Temporary Erosion and Sedimentation Control (TESC) Plan is shown on sheets GR-1 through GR-2 of the Jessie Glen plan set The TESC Plan was developed in accordance with criteria in Section 1.2.5 and Appendix D of the 2005 KCSWDM. Two sediment trap drainage basins were placed in the proposed north and south areas following existing topography with the intent of preventing to the maximum extent possible, the transport of sediment from the project site to downstream drainage facilities, water resources, and adjacent properties. The soils and hydrology of the proposed project site are described in Section 4.0. The 15-minute peak discharge from the 2 year storm event was used to size the sediment traps. Table 6 is a summary of the sediment trap drainage basins hydrology calculations. The sediment traps have been sized with 3:1 side slopes, 1.5 feet of sediment storage depth, 2 feet of settling depth, and 1 foot of overflow depth. rrable 6 -Sediment Trap Area 2 year Peak FlowBasinCharacteristics (ac) ( cfs) Trap 1 1.58 0.45 Trap 2 1.73 0.40 Detailed calculations are attached following this section. 9/28/2005 JESSIE GLEN SEDIMENT TRAP SIZING Temporary Erosion and Sediment Control Plan (TESCP) Sediment Trap Parameters Maximum basin contributing area (acres) Settling Velocity (feeUsecond) Sediment Storage (feet) Settling Depth (feet) Overfow (feet) Total Depth (feet) Sediment Trap Sizing Sediment Trap #1 Trap Top Elev. 508.0 Width at Top of Sed. Star. 14 Length at Top of Sed. Star. 24 Settling Depth feet) 2.0 Impervious Contributing Area (acres) 0.83 Pervious Contributing Area ~acres) 0.75 tal Contributing ea (acres) 1.58 15-minute 2yr Flow cfs) . 0.45 Design Surface Area(square feet) 931 Trap Surface Area (square feet) 1131 Table for Plans 3.0 0.00096 1.5 2.0 1.0 4.5 Sediment Trap #2 503.0 14 24 2.0 0.68 1.05 1.73 OAO 832 1131 S d' t T #1 S d' t T #2eImenrapeImenrap Bottom Width 5 5 Bottom Length 15 15 Top Width 32 32 Top Length 42 42 Side Slopes 3: 1 3:1 Over. Elev. 507.0 502.0 Bottom Elev. 503.5 498.5 5' Bench Elev. 508.0 503.0 IIEsm81eng rlES M-J 0 BSI1166\001 10051wo rks 12 005-08-04 KCRTSIsedim enttra ptab le.xls Laura Cociasu, PE Flow Frequency Analysis LogPearson III Coefficients Time Series File:sedl.tsf Mean= -0.312 StdDev~ 0.167 Project Location:Sea-Tac Skew~ 1. 399 Annual Peak Flow Rates--------Flow Frequency Analysis------- Flow Rate Rank Time of Peak - -Peaks Rank Return Prob CFS) (CFS) Period 0.685 9 2/16/49 l7: 45 1. 99 1 89.50 0.989 0.931 5 3/03/50 15:00 1.18 2 32.13 0.969 0.389 35 8/27/51 18:00 1. 05 3 19.58 o . 949 o .464 27 10/17/51 7:15 0.960 4 14.08 0.929 0.332 44 9/30/53 3:00 0.931 5 10.99 0.909 0.384 37 12/19/53 17:30 0.767 6 9.01 0.889 0.318 46 7/30/55 21:15 0.709 7 7.64 0.869 0.478 21 10/04/55 10:00 0.702 8 6.63 0.849 0.473 23 12/09/56 12: 45 0.685 9 5.86 0.829 0.434 32 1/16/58 10:00 0.571 10 5.24 0.809 0.545 14 10/18/58 19: 45 0.562 11 4.75 0.789 0.557 13 10/10/59 22:00 0.560 12 4.34 0.769 0.471 25 2/14/61 20: 15 0.557 13 3.99 0.749 0.383 38 8/04/62 13: 15 0.545 14 3.70 0.729 0.380 39 12/01/62 20: 15 0.516 15 3.44 0.709 0.294 49 6/05/64 15:00 0.511 16 3.22 0.690 0.444 30 4/20/65 19:30 0.510 l7 3.03 0.670 0.295 48 1/05/66 15:00 0.498 18 2.85 0.650 0.511 16 11/13/66 17: 45 0.495 19 2.70 0.630 1. 05 3 8/24/68 15:00 0.478 20 2.56 0.610 0.454 29 10/20/68 12:00 0.478 21 2.44 0.590 0.271 50 1/13/70 20:45 0.475 22 2.32 0.570 0.328 45 12/06/70 7:00 0.473 23 2.22 0.550 0.709 7 12/08/71 17:15 0.472 24 2.13 0.530 0.386 36 4/18/73 9:30 0.471 25 2.04 0.510 0.475 22 11/28/73 8:00 0.471 26 1. 96 0.490 0.495 19 8/17/75 23:00 0.464 27 1. 89 0.470 0.348 42 10/29/75 7:00 0.456 28 1. 82 0.450 0.311 47 8/23/77 14:30 0.454 29 1. 75 0.430 0.560 12 9/17/78 1:00 0.444 30 1. 70 0.410 0.767 6 9/08/79 13: 45 0.440 31 1. 64 0.390 0.562 11 12/14/79 20:00 0.434 32 1. 59 0.370 0.516 15 9/21/81 8:00 0.423 33 1. 54 0.350 1.18 2 10/05/81 22: 15 0.404 34 1. 4 9 0.330 0.472 24 10/28/82 16:00 0.389 35 1. 45 0.310 0.364 40 1/02/84 23: 45 0.386 36 1. 41 0.291 0.333 43 6/06/85 21:15 0.384 37 1. 37 0.271 o . 498 18 10/27/85 10:45 0.383 38 1. 33 0.251 0.571 10 10/25/86 22:45 0.380 39 1. 30 0.231 0.456 28 5/13/88 17:30 0.364 40 1.27 0.211 0.423 33 8/21/89 16:00 0.360 41 1. 24 0.191 0.702 8 1/09/90 5:30 0.348 42 1.21 0.171 0.471 26 4/03/91 20:15 0.333 43 1. 18 0.151 0.360 41 1127/92 15:00 0.332 44 1. 15 0.131 0.440 31 6/09/93 12:15 0.328 45 1.12 0.111 0.404 34 11/17/93 16:45 0.318 46 1.10 0.091 0.478 20 6/05/95 17:00 0.311 47 1. 08 0.071 0.510 17 5/19/96 11: 30 0.295 48 1. 05 0.051 1. 99 1 12/29/96 11: 45 0.294 49 1. 03 0.031 0.960 4 10/04/97 14:15 0.271 50 1. 01 0.011 computed Peaks 1.72 100.00 0.990 Computed Pea ks 1. 38 50.00 0.980 Computed Peaks 1.11 25.00 0.960 Computed Peaks 0.816 10.00 0.900 Computed Peaks 0.768 8.00 0.875 Computed Peaks 0.640 5.00 0.800 Computed Peaks 0.447 2.00 0.500 Computed Peaks 0.362 1. 30 0.231 Flow Frequency Analysis LogPearson III Coefficients Time Series File: sed2. tsf Mean= -0.361 StdDev~ 0.182 Project Location:Sea-Tac Skew~ 1. 452 Annual Peak Flow Rates--------Flow Frequency Analysis------- Flow Rate Rank Time of Peak - -Peaks Rank Return Prob CFS) (CFS) Period 0.650 8 2/16/49 17: 45 2.01 1 89.50 0.989 0.916 5 3/03/50 15:00 1. 14 2 32.13 0.969 0.333 37 10/08/50 4:15 0.981 3 19.58 0.949 0.416 26 10/17/51 7:15 0.934 4 14.08 0.929 0.284 45 9/30/53 3:00 0.916 5 10.99 0.909 0.347 34 12/19/53 17:30 0.710 6 9.01 0.889 0.280 46 11/25/54 1:00 0.678 7 7.64 0.869 0.392 31 10/04/55 10:00 0.650 8 6.63 0.849 0.454 17 12/09/56 12:45 0.644 9 5.86 0.829 0.399 29 1/16/58 10:00 0.532 10 5.24 0.809 0.472 14 10/18/58 19: 45 0.507 11 4.75 0.789 0.507 11 10/10/59 22:00 0.489 12 4.34 0.769 0.437 20 2/14/61 20:15 0.476 13 3.99 0.749 0.314 42 8/04/62 13: 15 0.472 14 3.70 0.729 0.342 35 12/01/62 20:15 0.469 15 3.44 0.709 0.248 49 12/31/63 21 :00 0.461 16 3.22 0.690 0.420 23 4/20/65 19:30 0.454 17 3.03 0.670 0.264 47 1/05/66 15:00 0.442 18 2.85 0.650 o .469 15 11/13/66 17 :45 0.438 19 2.70 0.630 0.981 3 8/24/68 15:00 0.437 20 2.56 0.610 0.409 27 10/20/68 12:00 0.435 21 2.44 0.590 0.242 50 1/13/70 20:45 0.423 22 2.32 0.570 0.296 43 12/06/70 7:00 0.420 23 2.22 0.550 0.678 7 ~2/08/71 17:15 0.419 24 2.13 0.530 0.326 39 4/18/73 9:30 0.417 25 2.04 0.510 0.435 21 11/28/73 8:00 0.416 26 1.96 0.490 0.417 25 12/26/74 20: 15 0.409 27 1. 89 0.470 0.315 41 10/29/75 7:00 0.403 28 1. 82 0.450 0.260 48 8/26/77 1:00 0.399 29 1. 75 0.430 0.476 13 9/17/78 1:00 0.397 30 1. 70 0.410 0.644 9 9/08/79 l3: 45 0.392 31 1. 64 0.390 0.532 10 12/14/79 20:00 0.374 32 1. 59 0.370 0.423 22 9/21/81 8:00 0.347 33 1. 54 0.350 1.14 2 10/05/81 22:15 0.347 34 1. 49 0.330 0.419 24 10/28/82 16:00 0.342 35 1. 45 0.310 0.336 36 1/02/84 23:45 0.336 36 1. 41 0.291 0.291 44 6/06/85 21:15 0.333 37 1. 37 0.271 0.442 18 10/27/85 10:45 0.332 38 1. 33 0.251 0.489 12 10/25/86 22: 45 0.326 39 1. 30 0.231 0.374 32 5/13/88 17:30 0.325 40 1. 27 0.211 0.347 33 8/21/89 16:00 0.315 41 1. 24 0.191 0.710 6 1/09/90 5:30 0.314 42 1.21 0.171 0.438 19 4/03/91 20:15 0.296 43 1.18 0.151 0.325 40 1/27/92 15:00 0.291 44 1. 15 0.131 0.403 28 6/09/93 12:15 0.284 45 1. 12 0.111 0.332 38 11/17/93 16:45 0.280 46 1. 10 0.091 0.397 30 6/05/95 17:00 0.264 47 1. 08 0.071 0.461 16 5/19/96 11: 30 0.260 48 1. 05 0.051 2.01 1 12/2 9/96 11: 45 0.248 49 1. 03 0.031 0.934 4 10/04/97 14: 15 0.242 50 1. 01 0.011 computed Peaks 1. 74 100.00 0.990 Computed Peaks 1. 37 50.00 0.980 Computed Peaks 1. 07 25.00 0.960 Computed Peaks 0.762 10.00 0.900 Computed Peaks 0.713 8.00 0.875 Computed Peaks 0.584 5.00 0.800 Computed Peaks 0.395 2.00 0.500 Computed Peaks 0.316 1. 30 0.231 Bond Quantities, Facility Summaries and Declaration of Covenant A Stormwater Facility Summary Sheet and a Site Improvement Bond Quantity Worksheet have been included following this page. KING COUNTY, WASHINGTON, SURFACE WATER DESIGN MANUAL STORMW A TER FACILITY SUMMARY SHEET Number DOES Permit cc provide one Stormwater Facility Summary Sheet per Natural Discharge Location) Overview: Project Name jd"l-'e.ss=i'-"-~___=_<9=lA=_\Il_'______ ______ Date______'~41=2-'-+ll~05=--- Downstream Drainage Basins Major Basin Name 500:5 ~ l>I&.iKa'1 ~S;I'I. Immediate Basin Name ----------- Flow Control: Flow Control Facility NamelNumber CoM4Jn'H,tg{ uJU-~IlHdJJeleuliM 1iti!J'",! Facility Location OJ( r/JI(tj,M-Stle-" .fJJ4f-¥120ru Atte SE I S'OI),.fh at RoA 1> A- Ifnone, Flow control provided in regional/shared facility (give location ),-----,-------,----c:-------~-____:_- No flow control required Exemption number General Facility Information: TypelNumber of detention facilities: TypelNumber of infiltration facilities: V ponds C> ponds vaults 0 tanks tanks 0 trenches Control Structure Location .1 SOu.tU.eM r urnur sf tiJW'(ll1 plJY/D/ Type of Control Structure _____________ Number of OrificeslRestrictions 3 Size of OrificelRestriction: No.1 /.55 No. 2 ~2~.s:~5:<-__ No. 3 ----"'2'-'-,7-'-<3"'----__ _ NO.4 ______ _ Flow Control Performance Standard _-"Leo.<LJUAe.!CLif,,-_ .. 2~,~ ______ _ 2005 Surface Water Design Manual 111105 1 KING COUNTY, WASHINGTON, SURFACE WATER DESIGN MANUAL Live Storage Volumlfl~ ~31043 U\.~ Depth 't fed: Volume Factor of Safety 2..3 ,:~ Number of Acres Served /.1 O)1Sik cl..tveLopeq -I-:l "If iJffl'/c CJM.tfpl.ltlbped Number of Lots _---'Lf_~-'-----___ _ Dam Safety Regulations (Washington State Department of Ecology) Reservoir Volume above natural grade ______ _ Depth of Reservoir above natural grade ______ _ Facility Summary Sheet Sketch All detention, infiltration and water quality facilities must include a detailed sketch. II "x 17" reduced size plan sheets may be used) 1i1/05 2005 Surface Water Design Manual 2 Maintenance and Operations Manual Excerpts from Appendix A of the 2005 KCSWDM have been included to guide in the operation and maintenance of the proposed combined wetpond and detention stormwater facility. along with the conveyance system. 1lesm8lengrlesm-jobsl 11661001 1005ldocumentltir-stormreportdoc KING COUNTY, WASHINGTON, SURFACE WATER DESIGN MANUAL APPENDIX A MAINTENANCE REQUIREMENTS FOR FLOW CONTROL, CONVEYANCE, AND WQ FACILITIES NO.1 -DETENTION PONDS Maintenance Defect or Problem Conditions When Maintenance Is Needed Results Expected When Component Maintenance Is Performed General Trash & Debris Any trash and debris which exceed 1 cubic foot Trash and debris cleared from site. per 1,000 square feet (this is about equal to the amount of trash it would take to fill up one standard size office garbage can). In gener~1. there should be no visual evidence of dumping. Poisonous Vegetation Any poisonous or nuisance vegetation which may No danger of poisonous vegetation Dr Noxious Weeds constitute a hazard to County personnel or the where County personnel or the public. public might normally be. Coordination with Seattle~King County Health Department Contaminants and Oil, gasoline, or other contaminants of one gallon No contaminants present other than Pollution or more, or any amount found that could: a surface film. (Coordination with 1) cause damage to plant, animal. or marine life; Seattle/King County Health 2) constitute a fire hazard; or 3) be flushed Department) downstream during rain storms. Unmowed If facility is located in private residential area, When mowing is needed, Grass/Ground Cover mowing is needed when grass exceeds 18 grass/ground cover should be inches in height. In other areas, the general mowed to 2 inches in height. policy is to make the pond site match adjacent Mowing of selected higher use areas ground cover and terrain as long as there is no rather than the entire slope may be interference with the function of the facility. acceptable for some situations. Rodent Holes Any evidence of rodent holes if facility is acting Rodents destroyed and dam or berm as a dam or berm, or any evidence of water repaired. (Coordination with piping through dam or berm via rodent holes or Seattle/King County Health other causes. Department) Insects When insects such as wasps and hornets Insects destroyed or removed from intenere with maintenance activities. Mosquito site. Mosquito control: Swallow complaints accompanied by presence of high nesting boxes or approved larvicide mosquito larvae concentrations (aquatic phase). applied. Tree Growth Tree growth threatens integrity of berms acting Trees do not hinder maintenance as dams. does not allow maintenance access, or activities. Harvested trees should interferes with maintenance activity (i.e., slope be recycled into mulch or other mowing, silt removal, vactoring, or equipment beneficial uses (e.g., alders for movements). If trees are a threat to berm firewood). integrity or not interfering with access, leave trees alone. 2005 Surface Water Design Manual -Appendix A 1/24/2005 A-I APPENDIX A MAINTENANCE REQUIREMENTS FLOW CONTROL, CONVEYANCE, AND WQ FACILITIES NO.1 -DETENTION PONDS Maintenance Defect or Problem Conditions When Maintenance Is Needed Results Expected When Component Maintenance Is Performed Side Slopes of Pond Erosion Eroded damage over 2 inches deep where cause Slopes should be stabilized by using of damage is still present or where there is appropriate erosion control potential for continued erosion. measure(s); e.g., rock Any erosion observed on a compacted benn reinforcement, planting of grass, embankment. compaction. If erosion is occurring on compacted berms a licensed civil engineer should be consulted to resolve source of erosion. Storage Area Sediment Accumulated sediment that exceeds 10% of the Sediment cleaned out to designed designed pond depth. pond shape and depth; pond reseeded if necessary to control erosion. UnerDamage Uner is visible and has more than three 'X.-inch Uner repaired or replaced. If Applicable) holes in it. Pond Berms (Dikes) Settlement Any part of berm that has settled 4 inches lower Dike should be built back to the than the design elevation. Settling can be an design elevation. indication of more severe problems with the berm or outlet works. A licensed civil engineer should be consulted to determine the source of the settlement. Emergency Tree Growth Tree gro'vVth on emergency spillways create Trees should be removed. If root Overflow/Spillway blockage problems and may cause failure of the system is small (base less than 4 and Berms over 4 berm due to uncontrolled overtopping. inches) the root system may be left feet in height. Tree growth on berms over 4 feet in height may in place. Otherwise the roots should be removed and the berm restored. lead to piping through the berm which could lead A licensed civil engineer should be to failure of the berm. consulted for proper berm/spillway , restoration. Emergency Rock Missing Only one layer of rock exists above native soil in Replace rocks to design standards. Overflow/Spillway area five square feet or larger, or any exposure of native soil at the top of out flow path of spillway. Rip-rap on inside slopes need not be replaced. 1/24/2005 2005 Surface Water Design Manual-Appendix A A-2 APPENDIX A MAINTENANCE REQU[REMENTS FOR FLOW CONTROL, CONVEYANCE, AND WQ FAC[LIT[ES NO.4 -CONTROL STRUCTURE/FLOW RESTRICTOR Maintenance Defect or Problem Condition When Maintenance is Needed Results Expected When Component Maintenance is Performed General Trash and Debris Distance between debris build-up and bottom of All trash and debris removed. Includes Sediment) orifice plate is less than 1.5 feet Structural Damage Structure is not securely attached to manhole Structure securely attached to wall wall and outlet pipe structure should support at and outlet pipe. least 1,000 Ibs of up or down pressure. Structure is not in upright position (allow up to Structure in correct position. 10% from plumb). Connections to outlet pipe are not watertight and Connections to outlet pipe are water show signs of rust. tight; structure repaired or replaced and works as designed. Any holes-other than designed holes-in the Structure has no holes other than structure. designed holes. Cleanout Gate Damaged or Missing Cleanout gate is not watertight or is missing. Gate is watertight and works as designed. Gate cannot be moved up and down by one Gate moves up and down easily and maintenance person. is watertight. Chain/rod leading to gate is missing or damaged. Chain is in place and works as designed. Gate is rusted over 50% of its surface area. Gate is repaired or replaced to meet design standards. Orifice Plate Damaged or Missing Control device is not working properly due to Plate is in place and works as missing, out of place, or bent orifice plate. designed. Obstructions Any trash. debris. sediment. or vegetation Plate is free of all obstructions and blocking the plate. works as designed. Overflow Pipe Obstructions Any trash or debris blocking (or having the Pipe is free of all obstructions and potential of blocking) the overilow pipe. works as designed. Manhole See "Detention Tanks See "Detention Tanks and Vaults" Table No. 3 See "Detention Tanks and Vaults" and Vaults" Table No.3 2005 Surface Water Design Manual ~ Appendix A [/2412005 A-5 APPENDIX A MAINTENANCE REQUIREMENTS FLOW CONTROL, CONVEYANCE, AND WQ FACILITIES NO.5 -CATCH BASINS Maintenance Defect or Problem Conditions When Maintenance is Needed Results Expected When Component Maintenance is pelionned General Trash & Debris Trash or debris of more than ~ cubic foot which No Trash or debris located Includes Sediment) is located immediately in front of the catch basin immediately in front of catch basin opening or is blocking capacity of the basin by opening. more than 10%. Trash or debris (in the basin) that exceeds 1/3 the No trash or debris in the catch depth from the bottom of basin to invert the basin. lowest pipe into or out of the basin. Trash or debris in any inlet or outlet pipe blocking Inlet and outlet pipes free of trash or more than 1/3 of its height. debris. Dead animals or vegetation that could generate No dead animals or vegetation odors that could cause complaints or dangerous present within the catch basin. gases (e.g., methane). Deposns of garbage exceeding 1 cubic foot in No condition present which would volume. attract or support the breeding of insects or rodents. Structure Damage to Comer of frame extends more than :y". inch past Frame is even with curb. Frame and/or Top curb face into the street (If applicable). Slab Top slab has holes larger than 2 square inches Top slab is free of holes and cracks. or cracks wider than y.. inch (intent is to make sure all material is running into basin). Frame not sitting flush on top slab, i.e., Frame is sitting flush on top slab. separation of more than ~ inch of the frame from the top slab. Cracks in Basin Cracks wider than 12 inch and longer than 3 feet, Basin replaced or repaired to design WallsiBottom any eviden~ of soil particles entering catch standards. basin through cracks, or maintenance person judges that structure is unsound. Cracks wider than Y2 inch and longer than 1 foot No cracks more than '/4 inch wide at at the joint of any inleUoutiet pipe or any the joint of inlet/outlet pipe. evidence of soil particles entering catch basin through cracks. SettiemenV Basin has settled more than 1 inch or has rotated Basin replaced or repaired to design Misalignment more than 2 inches out of alignment. standards. Fire Hazard Presence of chemicals such as natural gas, oil No flammable chemicals present. and gasoline. Vegetation Vegetation growing across and blocking more No vegetation blocking opening to than 10% of the basin opening. basin. Vegetation growing in inleVoutlet pipe joints that No vegetation or root grow1h is more than 6 inches tall and less than 6 inches present. apart. Pollution Nonflammable chemicals of more than Y2 cubic No pollution present other than foot per three feet of basin length. surface film. Catch Basin Cover Cover Not in Place Cover is missing or only partially in place. Any Catch basin cover is closed open catch basin requires maintenance. Locking Mechanism Mechanism cannot be opened by on Mechanism opens with proper tools. Not Working maintenance person with proper tools. Bolts into frame have less than Y2 inch of thread. Cover Difficult to One maintenance person cannot remove lid after Cover can be removed by one Remove applying 80 Ibs. of lift; intent is keep cover from maintenance person. sealing off access to maintenance. Ladder Ladder Rungs Unsafe Ladder is unsafe due to missing rungs, Ladder meets design standards and misalignment, rust, cracks, or sharp edges. allows maintenance person safe , access. 1/24/2005 2005 Surface Water Design Manual-Appendix A A-6 APPENDIX A MAINTENANCE REQUIREMENTS FOR FLOW CONTROL, CONVEYANCE, AND WQ FACILITIES NO.5 -CATCH BASINS Maintenance Defect or Problem Conditions When Maintenance is Needed Results Expected When Component Maintenance is performed Metal Grates Unsafe Grate Grate with opening wider than 71s inch. Grate opening meets design If Applicable) Opening standards. Trash and Debris Trash and debris that is blocking more than 20% Grate free of trash and debris. of grate surface. Damaged or Missing. Grate missing or broken member(s) of the grate. Grate is in place and meets design standards. NO.6 -DEBRIS BARRIERS (E.G., TRASH RACKS) Maintenance Defect or Problem Condition When Maintenance is Needed Results Expected When Component Maintenance is Performed. General Trash and Debris Trash or debris that is plugging more than 20% Barrier clear to receive capacity of the openings in the barrier. flow. Metal Damaged/Missing Bars are bent out of shape more than 3 inches. Bars in place with no bends more Bars. than % inch. Bars are missing or entire barrier missing. Bars in place according to design. Bars are loose am rust is causing 50% Repair or replace barrier to design deterioration to any part of barrier. standards. NO.7 -ENERGY DISSIPATERS POC'S wcrr APPLY Maintenance Defect or Problem Conditions When Maintenance is Needed Results Expected When / Component Maintenance is Performed. External: ./ Rock Pad Missing or Moved Only one layer of rock exists above native soil in Replace rocks 7tandards. Rock area five square feet or larger, or any exposure of native soil. Dispersion Trench Pipe Plugged with Accumulated sediment that exceeds 20% of the Pipe cle~,ushed so that il Sediment design depth, matches sign. Not Discharging Visual evidence of water discharging at ~ must be redesigned or Water Properly concentrated points along trench {normal r uilt to standards. condition is a ~sheet flow H of water along tre/ Intent is to prevent erosion damage. Perforations Plugged. Over ~ of perforations in pipe ar~ with Clean or replace perforated pipe. debris and sediment. Water Flows Out Top Mainlenance pers~rater flowing out Facility must be rebuilt or of "Distributo( Catch during any storm less t the design storm or redesigned to standards. Basin. its causing or appe ikely to cause damage. Receiving Area Over-wate~~ area is causing or has No danger of landslides. Saturated potenti causing landslide problems. Intemal: ./ Manhole/Chamber warn~ Structure dissipating flow deteriorates to % or Replace structure to design Post. Baffles, Si of original size or any concentrated wom spot standards. Chamber exceeding one square foot which would make structure unsound. 2005 Surface Water Design Manual ~ Appendix A 1114/2005 A-7 APPENDIX A MAINTENANCE REQUIREMENTS FLOW CONTROL, CONVEYANCE, AND WQ FACILITIES NO.8 -FENCING Maintenance Defect or Problem Conditions When Maintenance is Needed Results Expected When Component Maintenance is Performed General Missing or Broken Any defect in the fence that permits easy entry to Parts in place to provide adequate Parts a facility. security. Erosion Erosion more than 4 inches high and 12·18 No opening under the fence that inches wide permitting an opening under a fence. exceeds 4 inches in height. Wire Fences Damaged Parts Post out of plumb more than 6 inches. Post plumb to within 1Y2 inches. Top rails bent more than 6 inches. Top rail free of bends greater than 1 inch. Any part of fence (including post, top rails, and Fence is aligned and meets design fabric) more than 1 foot out of design alignment. standards. Missing or loose tension wire. Tension wire in place and holding fabric. Missing or loose barbed wire that is sagging Barbed wire in place with less than more than 21h inches between posts. Y. inch sag between post. Extension arm missing, broken, or bent out of Extension arm in place with no shape more than 114 inches. bends larger than ~ inch. Deteriorated Paint or Part or parts that have a rusting or scaling Structurally adequate posts or parts Protective Coating condition that has affected structural adequacy. with a uniform protective coating. Openings in Fabric Openings in fabric are such that an 8-inch No openings in fabric. diameter ball could fit through. NO.9-GATES Maintenance Defect or Problem Conditions When Maintenance is Needed Results Expected When Component Maintenance is Periormed General Damaged or Missing Missing gate or locking devices. Gates and Locking devices in place. Members Broken or missing hinges such that gate cannot Hinges intact and lubed. Gate is be easily opened and closed by a maintenance working freely. person. Gate is out of plumb more than 6 inches and Gate is aligned and vertical. more than 1 foot out of design alignment. Missing stretcher bar, stretcher bands, and ties. Stretcher bar, bands, and ties in place. Openings in Fabric See "Fencing~ Table NO.8 See "Fencing~ Table NO.8 1/24/2005 2005 Surface Water Design Manual-Appendix A A-8 APPENDIX A MAINTENANCE REQUIREMENTS FOR FLOW CONTROL, CONVEYANCE, AND WQ FACILITIES NO, 10-CONVEYANCE PIPES AND DITCHES Maintenance Defect or Problem Conditions When Maintenance is Needed Results Expected When Component Maintenance is Performed Pipes Sediment & Debris Accumulated sediment that exceeds 20% of the Pipe cleaned of all sediment and diameter of the pipe. debris. Vegetation Vegetation that reduces free movement of water All vegetation removed $0 water through pipes. flows freely through pipes. Damaged Protective coating is damaged; rust is causing Pipe repaired or replaced. more than 50% deterioration to any part of pipe. Any dent that decreases the cross section area Pipe repaired or replaced. of pipe by more than 20%. Open Ditches Trash & Debris Trash and debris exceeds 1 cubic foot per 1,000 Trash and debris cleared from square feet of ditch and slopes. ditches. Sediment Accumulated sediment that exceeds 20% of the Ditch cleaned/flushed of all design depth, sediment and debris so that it matches design. Vegetation Vegetation that reduces free movement of water Water flows freely through ditches. through ditches. Erosion Damage to See "Detention Ponds~ Table No.1 See ~Detention Pondsn Table No.1 Slopes Rock Lining Out of Maintenance person can see native soil beneath Replace rocks to design standards. Place or Missing (If the rock lining. Applicable), NO.11-GROUNDS (LANDSCAPING) Maintenance Defect or Problem Conditions When Maintenance is Needed Results Expected When Component Maintenance is Performed Genera! Weeds Weeds growing in more than 20% of the Weeds present in tess than 5% of Nonpoisonous, not landscaped area (trees and shrubs only). the landscaped area. noxious) Safety Hazard Any presence of poison ivy or other poisonous No poisonous vegetation present in vegetation. landscaped area. Trash or Litter Paper, cans, bottles, totaling more than 1 cubic Area clear of Jitter. foot within a landscaped area (trees and shrubs only) of 1,000 square feet. Trees and Shrubs Damaged Limbs or parts of trees or shrubs that are split or Trees and shrubs with less than 5% broken which affect more than 25% of the total of total foliage with split or broken foliage of the tree or shrub. limbs. Trees or shrubs that have been blown down or Tree or shrub in place free of injury. knocked over. Trees or shrubs which are not adequately Tree or shrub in place and supported or are leaning over, causing exposure adequately supported; remove any of the roots. dead or diseased trees. 2005 Surface Water Design Manual .-Appendix A 1/24/2005 A,9 APPENDIX A MAINTENANCE REQUIREMENTS FLOW CONTROL, CONVEYANCE, AND WQ FACILITIES NO. 12 -ACCESS ROADS Maintenance Defect or Problem Condition When Maintenance is Needed Results Expected When Component Maintenance is Performed General Trash and Debris Trash and debris exceeds 1 cubic foot per 1,000 Roadway free of debris 'Nhich could square feet (Le., trash and debris would fill up damage tires. one standards size garbage can). Blocked Roadway Debris which CQuid damage vehicle tires (glass Roadway free of debris which could or metal). damage tires. Any obstruction which reduces clearance above Roadway overhead clear to 14 feet road surface to less than 14 feet. high, Any obstruction restricting the access to a 10-to Obstruction removed to allow at 12-foot width for a distance of more than 12 feet least a 12-foot access. or any point restricting access to less than a 10- foot width, Road Surface Settlement, Potholes, When any surface defect exceeds 6 inches in Road surface uniformly smooth with Mush Spots, Ruts depth and 6 square feet in area. In general, any no evidence of settlement, potholes, surface defect which hinders or prevents mush spots, or ruts. maintenance access. Vegetation in Road Weeds growing in the road surface that are more Road surface free of weeds taller Surface than 6 inches tall and less than 6 inches tall and than 2 inches. Jess than 6 inches apart within a 400-square foot area. Modular Grid Build-up of sediment mildly contaminated with Removal of sediment and disposal Pavement petroleum hydrocarbons. in keeping with Health Department recommendations for mildly contaminated soils or catch basin sediments. Shoulders and Erosion Damage Erosion within 1 foot of the roadway more than 8 Shoulder free of erosion and Ditches inches wide and 6 inches deep. matching the surrounding road. Weeds and Brush Weeds and brush exceed 18 inches in height or Weeds and brush cut to 2 inches in hinder maintenance access. height or cleared in such a way as to allow maintenance access. 112412005 2005 Surface Water Design Manual-Appendix A A-IO APPENDIX A MAINTENANCE REQUIREMENTS FOR FLOW CONTROL, CONVEYANCE, AND WQ FACILITIES NO. 16-WETPOND Maintenance Defect or Problem Condition When Maintenance is Needed Recommended Maintenance to Component Correct Problem Pond Area Water Level First cell empty, doesn't hold water. Line the first cell to maintain at least 4 feet of water. Although the second cell may drain, the first cell must remain full to control turbulence of the incoming now and reduce sediment resuspension. Defective Vegetation Vegetation such as grass and weeds need to be Vegetation should be mowed to 4 to mowed when it starts to impede aesthetics of 5 inches in height. Trees and pond. MOwing is generally required when height bushes should be removed where exceeds 18 inches. Mowed vegetation should be they are interfering with pond removed from areas where it could enter the maintenance activities; that is, at the pond, either when the pond level rises, or by inlet. outlet and near engineered rainfall runoff. structures. Algae Mats When algae mats develop over more than 10% Algae mats that cover more than of the water surface, they should be removed. 10% of the surface of any cell Also remove mats in the late summer before fall should be removed. A rake or rains, especially in Sensitive Lake Protection mechanical device should be used Areas. Excessive algae mats interfere with to remove the algae. Removed dissolved oxygen content in the water and pose a algae can be left to dry on the pond threat to downstream lakes if excess nutrients slope above the 1DO-year water are released. surface. Trash and Debris Accumulation that exceeds 1 cubic foot per 1000 Trash and debris removed from square foot of pond area. pond. Sediment Sediment accumulations in pond bottom that Removal of sediment from pond Accumulation exceeds the depth of sediment zone plus 6 bottom. inches, usually in the first cell. Oil Sheen on Water Prevalent and visible oil sheen. Remove oil from water by use of oil- absorbent pads or by vactor truck. Refer problem to locate source and correct. If chronic low levels of oil persist, plant wetland plants such as Juncus effusus (soft rush) which can uptake small concentrations of oil. Erosion Erosion of the pond's side slopes and/or Slopes should be stabilized by using scouring of the pond bottom, that exceeds 6 proper erosion control measures, inches, or where continued erosion is prevalent. and repair methods. Pond Dike/Berm Settlement Any part of these components that has settled 4 Dike/berm is repaired to inches or lower than the design elevation, or specifications. inspector determines dike/berm is unsound. Internal Berm Concentrated Flow Berm dividing cells should be level. Build up low areas of berm or lower high areas so that the berm surface is level and water flows evenly over the entire length of the berm from the first cell to the second. Inlet/Outlet Pipe Sediment and Debris InleVOutlet pipe clogged with sediment andlor No clogging or blockage in the inlet debris material. and outlet piping. Overflow Spillway Rock Missing Rock is missing and soil is exposed at top of Replace rocks to specifications. spillway or outside slope. 2005 Surface Water Design Manual-Appendix A 1/24/2005 A·13 Site Improvement Bond Quantity Worksheet Web date: 1112112005 King County Department of Development & Environmental Services 900 Oakesdale Avenue Southwest Renton, Washington 98055-1219 206-296-6600 TTY 206-296-7217 Project Name: Jessie Glen Location: King County Clearing greater than or equal to 5,000 board feet of timber? yes If yes, Forest Practice Permit Number: RCW 76.09) Page 1 Of 9 Est-002.xls Lno For alternate formats, call 206-296-6600. Date: 4/13/2006 Project No.: L050005 Activity No.: L05SR054 Note: All prices include labor, equipment, materials, overhead and profit. Prices are from RS Means data adjusted for the Seattle area or from local sources if not included in the RS Means database. l> JJ 15/Z " m Z :;0 0c'" ~(') I-' m cnO ~ _ c:: < oz '" $::! g m ~ 0).-. en _ orr;;i~" Unit prices updated: 02/12/02 Version: 04/22/02 Report Date: 411212006 Page 2 of 9 Est-002.xls Site Improvement Bond Quantity Worksheet ESC SUBTOTAL: 30% CONTINGENCY & MOBILIZATION: ESC TOTAL: COLUMN: Web date: 1112112005 51,743,12 15,522,94 67,266.06 A Unit prices updated: 02/12102 Version: 04/22/02 Report Date: 411212006 Page 3 of 9 KCC 27 A authorizes only one bond reduction. Est·Q02.)(1s Site Improvement Bond Quantity Worksheet SUBTOTAL 80,842.79 Web dale: 11/21/2005 Unit prices updated: 02112/02 Version: 4/22102 Report Date: 4/12/2006 Page 4 of 9 KCC 27A authorizes only one bond reduction. Est-002.xls Site Improvement Bond Quantity Worksheet SUBTOTAL 79,204.80 Web dale: 11/21/2005 Unit prices updated: 02/12/02 Version: 4122/02 Report Date: 4/12/2006 Page 5 of 9 KCC 27A authorizes only one bond reduction. Est~002.xls Site Improvement Bond Quantity Worksheet SUBTOTAL 77,836.00 Web date: 11121/2005 9,480.65 Unit prices updated: 02/12/02 Version: 4122102 Report Date: 4/12/2006 Page 6 of9 KCC 27A authorizes only one bond reduction. Est-002.xls Site Improvement Bond Quantity Worksheet SUBTOTAL 58,162.39 Web date: 11121/2005 Unit prices updated: 02/12/02 Version: 4122102 Report Date: 4/12/2006 Page 7 of 9 KCC 27A authorizes only one bond reduction. Est~002.xls Site Improvement Bond Quantity Worksheet SUBTOTAL 70819.73 Web date: 1112112005 Unit prices updated: 02/12/02 Version: 4122102 Report Date: 4/12/2006 Site Improvement Bond Quantity Worksheet SUBTOTAL SUBTOTAL (SUM ALL PAGES): 30% CONTINGENCY & MOBILIZATION: Page 8 of 9 KCC 27A authorizes only one bond reduction. Est-002.xls GRANDTOTAL: COLUMN: 366,865.71 110,059.71 476,925.42 B C Web dale: 11121/2005 9,480.65 2,844.20 12,324.85 o E Unit prices updated: 02/12102 Version: 4122/02 Report Date: 4/12/2006 Site Improvement Bond Quantity Worksheet Web date: 11/2112005 Original bond computations prepared by: Name: Jessie Glen Date: 4113/2006 PE Registration Number: 40111 Tel. #: 1-800-345-5694 Finn Name: ESM Constulting Engineers, LLC Address: 33915 1st Way South, Suite #200, Federal Way, WA 98003 Project No: L050005 ROAD IMPROVEMENTS & DRAINAGE FACILITIES FINANCIAL GUARANTEE REQUIREMENTS Stabilization/Erosion Sediment Control (ESC) ) (A) Exisllng Right-ai-Way Improvements (B) Future Public Road Improvements & Drainage Facilitie (C) Private Improvements (D) $ Calculated Quantity Completed PERFORMANCE BOND' AMOUNT 67,266.1 476,925.4 12,324.8 Total Right-ol Way and/or Site Restoration Bond'/" First $7,500 01 bond' shall be cash.) A+B) $ 67,266.1 BOND' AMOUNT REQUIRED AT RECORDING OR TEMPORARY OCCUPANCY'" E) $ Performance Bond' Amount (A+B+C+D) = TOTAL (T) $ 556,516.3 Minimum bona; amount IS $1000. T x 0.30 $ 166,954.9 Reduced Performance Bond· Total U. Maintenance/Defect Bond· Total NAME OF PERSON PREPARING BOND' REDUCTION: ~L-&~l~ NOTE: The word "bond" as used in this document means any financial guarantee acceptable to King County. NOTE: KeC 27A authorizes right of way and site restoration bonds to be combined when both are required. T-E) $ 556,516.3 Use larger of Tx30% or (T-E) OR Date: PUBLIC ROAD & DRAINAGE MAINTENANCE/DEFECT BOND' B+C) X 0.25= $ 119,231.4 1.;//3/0{' : : I The restoration requirement shall include the total cost for all TESC as a minimum, not a maximum. In addition, corrective work, both on-and off-site needs to be included. Quantities shall reflect worse case scenarios not just minimum requirements. For example, if a salmonid stream may be damaged, some estimated costs for restoration needs to be reflected in this amount. The 30% contingency and mobilization costs are computed in this quantity. NOTE: Per KeC 27A, total bond amounts remaining after reduction shall not be less than 30% of the original amount (T) or as revised b major design changes. SURETY BOND RIDER NOTE: If a bond rider is used, minimum additional performance bond shall be $ 489,250.3 (C+D)-E REQUIRED BOND' AMOUNTS ARE SUBJECT TO REVIEW AND MODIFICATION BY DDES Page 9 019 Est-002.xls Check out the DDES Web site at www.metrokc.qov/ddes Unit prices updated: 02/12/02 Version: 4122102 Report Date: 4/12/2006 OSSR05~ SIGNIFICANT TREE BOND QUANTITY WORKSHEET (Planting & Existing Trees) Complete and return electronically) Date: 2}3/ 0 & , Project NameJtS01L 61 tA DDES Project Number: L0 5 P (Xf) 5 Trees (Nursery Trees SUBTOTAL 30% CONTINGENCY & MOBILIZATION TOTAL PERFORMANCE BOND AMOUNT First $2500.00 shall be cash L'Mli Quantity Calculations completed bY:1f!nmUU(l:/~ Approved by Site Development Specialist: (/ Use Tree Value for lumber mill prices at minimum RECEIVED FEB 1 I) 2006 KING COUNlY LAND USE SERVICES