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HomeMy WebLinkAbout03554 - Technical Information Report - Drainage � � m � ENGINEERING REPORT Drrtirt�ge Report Hazen High School Classroom Addition Renton,WA Fee�an�i y,�uio .� � . - � :� � , :� L �--� 25 zoi� ��:r,` ' �,. _ " _ ''t�; �11�')�;(�.i!'^�i PREPARED FOK: Renton School District 7812 South 124�Street Seattle,WA 98178 Contact: Stewart Shusterman `1�� C� �Q� PREPARED THROUGH: '4j' "���'�`A'�� �► DLR Group '� F?'� �.:' E., ��= 901 Fifth Ave,Suite 700 � �� -�, Seattle,W A 98164 � ' Contact: Larr�� Ahern � ___ �� �L1. � ` � w��'°P�m'% � ��SSIONAL ��`� Z� �9�2�� � PREPARED BY: C OUG H LI N PORTE RLUN D EE N 413 Pine Street,Suite 300 Seattle,Washington 98101 P:206/343-04b0 Contact: Alan Jacobson,P.E. �ct 35�s� TECHNICAL INFORMATION REP - Renton School District No.403 Hazen High School Classroom Additi Coughlin Porter Lundeen Project No.C09- Februar� "CaBLE UF CU,'VTENTS Section Page I. PROJEC"T OVERVIEW........................................................................................................................................ 1 GeneralDescription....................................................................................................................................................... 1 ExistingConditions........................................................................................................................................................ I ProposedConditions..................................................................................................................................................... 1 II. CONDTTIONS AND REQUIREMENTS SUMMARY...................................................................................2 King County Surface Water Management Design Manual Core Requirements:................................................� SpecialRequirements:....................................................................................................................................................� Project Specific Requirements:.....................................................................................................................................3 III. OFF-SITE ANALYSIS..........................................................................................................................................� Task 1 -Study Area Definition and Maps..................................................................................................................-� Task2-Resource Review...............................................................................................................................................� Task3-Field Investigation............................................................................................................................................� Task 4-Drainage System Description and Problem Screening..............................................................................k Task 5-Mitigation of Existing or Potential Problems..............................................................................................� N. FLOW CONTROL AND WATER QUALTTY FACILTTY ANALYSIS AND DESIGN............................� PartA-Existing Site Hydrology..................................................................................................................................� PartB-Developed Site Hydrology............................................................................................................................. � Part C-Performance Standards..................................................................................................................................6 PartD-Flow Control System......................................................................................................................................h PartE-Water Quality System.....................................................................................................................................6 StandardRequirements.................................................................................................................................................6 V. CONVEYANCE SYSTEM ANALYSIS AND DESIGN.................................................................................7 On-site Conveyance.......................................................................................................................................................7 VI. SPECIAL REPORTS AND ST'[.JDIES...............................................................................................................7 VII. OTHER PERMl`I'5................................................................................................................................................7 VIII. CSWI'PP ANALYSIS AND DESIGN...............................................................................................................7 Part A-ESC Plan Analysis and Design.....................................................................................................................7 PartB-SWPI'S Plan Design.........................................................................................................................................8 IX. BOND QUANTTTIES,FACILTTY SUMMARIES,AND DECLARATION OF COVENANT.......................9 X. OPERATIONS AND MAINENANCE MANUAL......................................................................................10 Standard Maintenance...................... ..................................................................10 ......................................................... COUGHUNPORTERLUNDEEN Hazen High School Classroom Addition i Renton,Lti'ashington LIST OF FIGURES FIGURE Figure 1 -TIR Worksheet Figure 2-Site Location Figure 3a-Existing Site Conditions Figure 3b-Proposed Site Conditions Figure 4-Soils Map LIST OF TABLES Table 1 -Existing Site Conditions Area Breakdown.....................................................................................................5 Table 2-Developed Site Conditions Area Breakdown................................................................................................5 .APPENDICES Appendix A Figures Appendix B Supporting calculations • Detention • Conveyance • Backwater • T.E.S.C. Appendix C Geotechnical Report Appendix D Bond Quantities,Facility Summaries,and Declaration of Covenant Appendix E Operations and Maintenance Manual COUGHLINPORTERLUNDEEN Hazen High School Classroom Addition ii Renton,41'ashington I. PROJEC'I'OVERVIEW General Description The following Preliminary Drainage Report provides the technical information and design analysis required for developing the Drainage Plan for the Renton School District Hazen High School Classroom Addition. Hazen High School is located within the City of Renton at 1101 Hoquiam Avenue NE,(see Figure 2-Site Location)and is located within the May Geek drainage basin. The existing site consists of two classroom buildings,a gym building,and two portables with associated parking,landscape and walkways and sports fields. The terrain is fairly flat,falling generally north from the south. The Renton School District is proposing to construct a classroom addition of approximatel}'26,�00 square feet that will connect the existing site buildings. The addition will be two stories and take the shape of an "L",creating a courtyard betrveen the buildings. This courtyard will be both landscaped and hardscaped to provide an outdoor learning space. Stormwater runoff from the new courtyard area will sheet flow into rain gardens(water feature functionality only)within the new courtyard. The flow from these rain gardens will be picked up either by underdrains or an overflow structure and routed to a detention vault located below the courtyard. Downspouts from the new building roof will also be routed to the detention vault. Once discharged from the detention vault the water will be directed into the existing site storm system to the west of the new building. No water quality treatrnent will be provided onsite as there will be no added pollution generating impervious surfaces. Existing Conditions The existing project area of the Hazen High School site occupies approximately 1.74 acres and consists of two portable buildings,concrete walkways,grass landscaping,and a portion of an existing asphalt parking lot (see Table 1-Existing Project Site Conditions Area Breakdown). There are also storm,sewer,gas and electrical utility lines running underground in this area;many of these utilities will be relocated as part of the site work. The proposed site will consist of asphalt and concrete paving,a building footprint,and associated landscaping;resulting in approximately 37,390 SF of additional total site unpervious area(see Table 2- Proposed Project Site Conditions Area Breakdown).The project is located within the May Creek Drainage Basin which ultimately drains to Lake Washington. Currenfly the project area drains south out of the site to NE lOw Street(See Figure 3a-Existing Site Conditions). The on-site soils consist mainly of recessional outwash and fill material. The upper 7.�feet is fill material, which consists of materials from on-site which were moved and or disiurbed during eazlier work with a wide range of densities. Below the 7.5 feet of fill,is the outwash which is a silty sand with gravel,inter- bedded in places with fine sand zones or silt seams. The outwash was deposited by a receding glacier. (See Figure 4 for the USGS soils map and Appendix C for the Geotechnical Report). Proposed Conditions The proposed site area at Hazen High School will consist of a new two story building,a courtyard with rain gardens,associated hardscaping and landscaping,and the reconstruction of a portion of the existing parking lot to the west. Drainage unprovements will include building downspouts,rain gardens and catch basins to direct flows to the existing storm system on the west side of the new building(see Figure 3b-Proposed Site Conditions). As previously stated,storm water detention will be provided on-site with the use of an underground detention vault located below the new courtyard. Due to the geometry of the rain gardens, they do not provide very much detention capacity for this case,and are being ignored for the purpose of detention calculations,and will function more as a site water feature. Water quality treatrnent is not required onsite because w-e are not proposing any additional pollution generating impervious surfaces. COUGHLINPORTERLUNDEEN Hazen High Schcx�l Classroom Addirion 1 Renton,l�'ashingt��n II. CONDITIONS AND REQUIREMENTS SUMMARY This section will address the requirements set forth by the Core and Special Requirements listed in Chapter 1 of the KCSWDM (as adopted by the City of Renton). King County Surface Water Management Design Manual Core Requirements: 1. Discharge at a nafiural location(1.21): The existing and proposed discharge points are concurrenk 2. Off-site Analysis(1.2.2): This subject is covered in Sections III and N. Please refer to the Level 1 downstream analysis in those sections. 3. Flow Conriol(1.23): Leve12 flow control will be provided for the project azea per the requirements set forth in the 2005 KCSWDM. 4. Conveyanee System (1.2.4): This information and calculations are presented in Section V. Rain gardens and a closed pipe system have been provided for on-site stormwater conveyance. 5. Erosion and Sediment Control(1.25): The project will construct a series of sediment controLs to address the specific conditions at the site. DetaiLs are shown in Section IX. 6. Maintenanee and Operation(1.26): The proposed storm drainage system will be owned,operated and maintained by the owner. A maintenance and operation manual is included in Section XI. 7. Financial Guarantees and Liability(1.2.�: T'he owner and contractor will obtain all necessary permits prior to the begiruiing of construction. The owner will be responsible for required bonds. 8. Water Quality(1.28): This project does not require water quality treatrnent since the amount of pollution generating impervious surface is not changing. Special Requirements: Special Requirement#1. Other Adopted Area-Specific Requirements Section 1.3.1 • Critical Drainage Areas(CDAs):Not Applicable • Master Drainage Plans(MDPs):There are no known master drainage plans covering this project site. • Basin Plans(BPs):The project is located within the May Geek Basin Plan. There are no area specific drainage review thresholds for this area. • 'Salmon Conservation Plans:Not Applicable • Stormwater Compliance Plans:Not Applicable • Lake Management Plans(LMI's):Not Applicable • Flood Hazard Reduction Plan Updates:Not Applicable • Shared Facility Drainage Plans(SFDPs):Not Applicable COUGHLINPORTERLUNDEEN Hazen High School Classroom Addition 2 Renton,Washington Special Requirement#2. Floodplain/Floodway Delineation,Section 1.3.2: This project is not within a designated flood plain. Special Requirement#3. Flood Protection Facilities,Section 1.3.3: Not applicable Special Requirement#4. Source Control,Section 1.34: Since there aze no additional pollution generating surfaces,no source control is required onsite. Special Requirement#5. Oil Control: Not applicable Project Specific Requirements: There are no project specific requirements. COUGHLINPORTERLUNDEEN Hazen High School Classroom Addition 3 Renton,bVashington III. OFF-SITE ANALYSIS Task 1 - Study Area Definition and Maps See Figure 3a far drainage sulrbasins,discharge points from the site and other related information. Task 2 - Resource Review a) Adopted Basin Plans: May Creek Basin-does not affect project site. b) Finalized Drainage Studies: No information provided effects site work. c) Basin Reconnaissance Summary Reports: No information found for May Creek. d) Critical Drainage Area Maps: Not in critical Drainage areas. e) Floodplain/floodway(FEMA)Maps: Site not in 100-yr Floodplain fl Other Offsite Analysis Reports: No other reports available. g) Sensitive Areas Folio: Site is not part of a sensitive area. h) Drainage Complaints and Studies: No record of drainage complaints i) Road Drainage Problems: No record of road drainage problems j) King County SoiLs Survey: Soils information has been included,See Figure 4. k) Wetland Inventory Maps: Site is not within a wedand 1) Mitigating River Studies: River mitigarion does not affect site. Task 3 -Field Investigation A site visit has not been made to the project site to gather information for a Level l Downstream Analysis. However,survey,maps,and a past report by LPD Engineers from February 2009 have given us a picture of what is happening with offsite storm water. Please refer to the discussion below. Task 4 -Drainage System Description and Problem Screening Upstream Drainage Review There are no upstream flows flowing on to our project area. Level l Downstream Drainage Review The project site drains west and south through the on-site storm system and out into NE 10�Street. The storm drainage in NE 10�Street enters a regional detention facility approximately 900 feet downstream of the project site. T"his regional facility discharges back into NE 10�Street. From there,the storm system is directed down Anacortes Ave NE in a 36-inch main line. This 36-inch main eventually discharges into Honey Creek in the Whitman Court NE right of way,just south of NE Sunset Blvd. Honey Creek flows northwest and discharges to May Creek at May Creek Park. May Creek continues to flow northwest and outfalls into Lake Washington. Task 5 —Mitigation of Existing or Potential Problems T'here are no existing or foreseen potential problems that require mitigation. COUGHLINPORTERLUNDEEN Hazen High School Clas.sroom.addition 4 Renton,LVashington IV. FLOW CONTROL AND WATER QUALITY FACILITY ANALYSIS AND DESIGN This section describes the conditions that contribute to the storm water runoff values and mitigation efforts proposed for the site. Part A-Existing Site Hydrology The existing site hydrology consists of two existing portable buildings,concrete walkways and landscaping, and a portion of the existing asphalt parking lot. There are existing established storm water runoff conveyance lines and flow control for the entire site. The total project site area is 174 acres. The existing site conditions are shown in Figure 3a,from a documented field survey. The sifie is generally flat with a soft slope to the north. The project site drains south off the school site into NE 10�Street. The existing site conditions are summarized in Table 1 below. Table 1 -Existing Site Conditions Area Breakdown Drainage Basin Land Cover Area(acres) Description May Creek Impervious 0.86 Building,Concrete and Asphalt Paving Till Grass 0.88 Landscaping Total 1.74 Existing Project Site Area Part B - Developed Site Hydrology The proposed site hydrology consists of a new building addition,concrete walkways and landscaping including rain gardens,and a portion of the existing asphalt parking lot. T'he proposed drainage flow from the project site will tie into the existing storm drainage line to the west of the new building. Please refer to Figure 3b for proposed drainage areas. T'here are portions of the project area which due to location,and grading restraints,will not be able to be ' routed to the proposed detention vault. These areas have necessitated a Bypass condition has been noted ' and accounted for in the storm water design,and the combined flows(detention and bypass)have been ' evaluated as the allowable runoff. The developed site conditions are summarized in Table 2 below. Table 2-Developed Site Conditions Area Breakdoum Drainage Basin Land Cover Area(acres) Description May Creek Impervious 0.67 Building,Concrete and Asphalt Paving � Wetland 0.04 Rain Gardens I Till Grass 0.29 Landscaping I, Impenrious 0.48 Bypass Bldg, Co�tc.and Asphalt Pavirig �' Ti11 Grc�ss 0.26 Bypass Landscaping Total 1.74 Proposed Project Site Area COUGHLINPORTERLUNDEEN Hazen High School Classroom Addition � Renton,�Nashington Part C—Performance Standards • Area-Specific Flow Control Facility Standard-Flow control will be provided for this site with the use of an underground detention vault. See Part D of this section. • Conveyance System Capacity Standards-Conveyance calculations will be included for the on-site system in Appendix B. • Area-Specific Water Quality Treatment-Water quality is not required for this site. See Part E of this section for further discussion. Part D—Flow Control System Based on the 2005 King County Storm Water Drainage Manual,Basic Level 2 flow contr-ol will be provided for the proposed site area work. An underground detention vault is proposed in the new site courtyard area to provide the necessary flow control for the site. For preexisting conditions,we have modeled all areas as forest till except for those areas which are currendy impervious and will be converted to pervious areas per King County code as explained by KCDDES Engineer David Ratte December 07,2007(See Letter in Appendix C).According to Mr.Ratte,conversion of existing impervious to pervious areas does not meet the definition of"new pervious surface"found on page 1-4 of the 2009 KCSWDM,and is therefore not included in targeted review.Therefore for this project,these "exchanged"areas were modeled as preexisting impervious. Also modeled as preexisting impervious are impervious areas within the project limits that will not be disturbed as part of the work occurring onsite. Table 3-Preexisting Modeled Areas Drainage Basin Land Cover Area(acres) Description May Creek Impervious 0.51 Concrete and Asphalt Paving not disturbed by construction activity or being replaced by impervious Till Forest 1.23 Landscaping,Concrete and Asphalt paving,Building Total 1.74 Existing Project Site Area Part E—Water Quality System Standard Requirements This site will not provide water quality because there are no new pollution generating impervious surfaces proposed as part of the project,per Core Requirement#8. COUGHLINPORTERLUNDEEN Hazen High School Classroom Addition 6 Renton,SVashington V. CONVEYANCE SYSTEM ANALYSIS AND DESIGN On-site Conveyance The on-site conveyance rystem will consist of catch basins,six,eight and 12-inch conveyance lines,rain gardens,and an underground detention vault. The capacity of the proposed storm lines were evaluated using the Rational Method and a Manning's-based conveyance spreadsheet. Pipe capacity has been further evaluated using the Direct Step Backwater Method. The conveyance system has been designed to provide adequate slopes and sizes. Refer to Appendix B for conveyance and backwater calculations along with sub- basin maps and areas. VI. SPECIAL REPORTS AND STUDIES See appendix C for geotechnical report. VII. OTHER PERMITS An NPDES permit will be required for this project and will be filed separately with Ecology by the School District. VIII. SWPPP ANALYSIS AND DESIGN Part A-ESC Plan Analysis and Design Erosion/Sedimentarion Plan shall include the following: 1. Facilities required include:stabilized constrtcction entrance,sedirnentation pond,interceptor swales, filter fabric fencing. (1.2.5-1).The project will provide a construction entrance/exit,truck wheel wash, filter fabric fencing,a series of sediment tanks,and catch basin protection. See Appendix B for sediment tanlc calculations. 2. Timing-For the period betzueen Noverriber 1 through March 1 disf��rbed areas greater than 5,000 square feet left undisturbed for more than 12 hours must be covered with mulch,sodding,or plastic covering. A construction phasing plan shall be provided to ens:tre that erosion control measures are installed prior to clearing and grading. (1.2.5-1). Notes addressing each of these items have been placed on the civil engineering plans. 3. Planning-Plan sha11 limit tributary drainage to an area to be cleared and gradec� Delineate ciimension, stake and flag clearing Iimits(1.2.5-1). The clearing limits will be indicated on the T'ESC plan. Notes addressing this item have been placed on the civil engineering plans. 4. Re-vegetation—Re-vegetate areas to be cleared as soon as practicable aftergrading. (1.2.5-1). Notes addressing this item have been placed on the civil engineering plans. COUGHLINPORTERLUNDEEN Hazen High School Classroom Addition 7 Renton,�h'ashington T'he TESC plan for this project will be designed to protect off-site properties as well as to minim;�e the quantity of sediment-laden water that enters the public storm system. The following BMP's will be included on the TESC plan for this project. • Clearly delineated clearing limits staked prior to any construction activity. • Stabilized construction entrances with a wheel washing station for trucks exiting the site. All material that is tracked off the site will be cleaned by sweeping. • Catch basin protection will be used on all existing and future catch basins as they are installed, to reduce the amount of sediment that can enter the storm system. • Cover measures will be implemented for disturbed areas greater than 5,000 square feet in accordance with the King County standards. • Temporary sediment tanks will be included,if necessary,to allow the opportunity for sediment to settle out of on-site runoff prior to discharging from the site. All construction debris will be promptly removed from the site to minimi�.e demoiition and construction impacts to the site. The contractor will unplement additional BMP's as required or recommended by the City of Renton inspectors or other agencies as required. This will help prevent demolition and construction debris,waste material,fuel,oil,lubricants and other fluids from entering the public storm system. These measures will be shown on the TESC plan sheets included in the construction permit set. Part B- S WPPP Plan Design The site SWPPP will be completed by the project contractor and based on the civil TESC plan. COUGHLINPORTERLUNDEEN Hazen High School Classroom Addition 8 Renton,Washington IX. BOND QUANTITIES,FACILITY SUMMARIES,AND DECLARATION OF COVENANT Bond Quantity Worksheets Bond quantity worksheets are included in Appendix D. Flow Control and Water Quality Facility Summary Sheet and Sketch Flow Control summary and sketch are included in Appendix D. Declaration of Covenant for Privately Maintained Flow Control and WQ Facilities Declaration of Covenant is included in Appendix D. Declaration of Covenant for Privately Maintained Flow Control BMPs Dedaration of Covenant is included in Appendix D. COUGHLINPORTERLUNDEEN Hazen High School Classroom�lddition 9 Renton,�ti'ashington X. OPERATIONS AND MAINENANCE MANUAL Standard Maintenance Per standards set forth in the King County Surface Water Design Manual,the owner will maintain facilities. Sections of the King County Storm Water Management Design Manual outlining the Operations and Maintenance of these facilities are included in Appendix E. COUGHLINPORTERLUNDEEN Hazen High School Classroom AddiHon 10 Renton,j�Vashington APPEIVDIX A Figure 1 -TIR Worksheet Figure 2-Site Location Figure 3a-Eacisting Drainage System Figure 3b-Proposed Drainage System Figure 4-Soils Map COUGHLIN PORTER LUNDEEN Hazen HS Classroom Addition TECHNICAL INFORMATION REPORT (TIR) WORKSHEET Part 1 PROJECT OWNER AND Part 2 PROJECT LOCATION AND PROJECT ENGINEER DESCRIPTION Project Owner Ren:or. School District rk403 Project Name Hazen High School Classroom Addition PhOne 425-204-4429 DDES Pe►'mit# Address 7812 soucn izatn sereec Location Township 23 N seattle, WA 98178 Range 5 E Project Engineer Alan Jacobson Section 10 ,i Company Coughlin Porter Lundeen Site Address iioi Hoquiam Ave Na Phone z60-343-0460 Renton , WA 98059 Part 3 TYPE OF PERMIT APPLICATION Part 4 OTHER REVIEWS AND PERMITS ❑ Landuse Services ❑ DFW HPA ❑ Shoreline Subdivison / Short Subd. / UPD ❑ COE 404 Management � Buildin Services ❑ DOE Dam Safety � Structural M/F/ ommerica / SFR RockeryNaulU ❑ Clearing and Grading ❑ FEMA Floodplain ❑ ESA Section 7 ❑ Right-of-Way Use ❑ COE Wetlands , 0 Other site �laz xeview ❑ Other Part 5 PLAN AND REPORT INFORMATION Technical Information Report Site Improvement Plan (Engr. Plans) Type of Drainage Review ull / Targeted / Type (circle one): Full / odifie / I (circle): Large Site Small Site Date (include revision 8/6/09 Date (include revision 8/6/09 dates): dates): Date of Final: Date of Final: ' Part 6 ADJUSTMENT APPROVALS Type (circle one): Standard / Complex / Preapplication / Experimental/ Blanket ', Description: (include conditions in TIR Section 2) Date of A roval: ' ?0p5 Surface Water Design Ma�ual I11/0> 1 KING COUNTY, WASHINGTON, SURFACE WATER DESIGN MANUAL TECHNICAL INFORMATION REPORT (TIR) WORKSHEET Part 7 MONITORING REQUIREMENTS Monitoring Required: Yes / No Describe: Start Date: Completion Date: Part 8 SITE COMMUNITY AND DRAINAGE BASIN Community Plan : Special District Overlays: Drainage Basin: May Creek Stormwater Requirements: sasic Detention Part 9 ONSITE AND ADJACENT SENSITIVE AREAS ❑ River/Stream ❑ Steep Slope ❑ Lake ❑ Erosion Hazard ❑ Wetlands ❑ Landslide Hazard ❑ Closed Depression ❑ Coal Mine Hazard ❑ Floodplain ❑ Seismic Hazard i ❑ Other ❑ Habitat Protection ❑ Part 10 SOILS Soil Type Slopes Erosion Potential Outwash 6-15� ❑ High Groundwater Table (within 5 feet) ❑ Sole Source Aquifer ❑ Other ❑ Seeps/Springs ❑ Additional Sheets Attached '� 2005 Surface Water Design Manual 1/1/OS 2 h���� c u� � � ��. �� �,�f+���� � u�. ���[.} ���� �� � � �.}� 1>> �<<�� �� ��i_� �� TECHNICAL INFORMATION REPORT (TIR) WORKSHEET Part 11 DRAINAGE DESIGN LIMITATIONS REFERENCE LIMITATION/SITE CONSTRAINT ❑ Core 2—Offsite Analvsis ❑ Sensitive/Critical Areas ❑ SEPA ❑ Other ❑ ❑ Additional Sheets Attached Part 12 TIR SUMMARY SHEET rovide one TIR Summa Sheet r Threshold Dischar e Area Threshold Discharge Area: name or descri tion Develo ed srie Core Requirements(all 8 apply) Dischar e at Natural Location Number of Natural Dischar e Locations: 1 Offsite Analysis Level: Q/ 2 / 3 dated: Flow Control Level: 1 / 2 / 3 or Exemption Number incl.facilit summa sheet Small Site BM s Conveyance System Spill containment located at: Erosion and Sediment Control ESC Site Supervisor: Contact Phone: TBD After Hours Phone: Maintenance and Operation Responsibility: Privat / Public If Private, Maintenance Lo R uired: Ye /No Financial Guarantees and Provided: Yes / No TBD Liabilit Water Quality Type: Basic / Sens. Lake / Enhanced Basicm / Bog (include facility summary sheet) or Exemption No. Landsca e Mana ement Plan: Yes / No S ecial Re uirements as a licable Area Specific Drainage Type: CDA/SDO/MDP/BP/LMP/Shared Fac./ on Re uirements Name: Floodplain/Floodway Delineation Type: Major / Minor / Exemption / on 100-year Base Flood Elevation (or range): Datum: Flood Protection Facilities Describe: None Source Control Describe landuse: commer�iai (comm./industrial landuse) Describe any structural controls: None 2005 Surface Water Design Manual 1/1/OS 3 KING COUNTY, WASHINGTON, SURFACE WATER DESIGN MANUAL T�r'u�llr`�I IR1�r1R�/!�TI(l�l R�P(1RT /TIR1 1/1!(IRKCNF� Oil Control High-use Site: Yes � Treatment BMP: Maintenance Agreement: Yes /Do with whom? Other Draina e Structures Describe: Part 13 EROSION AND SEDIMENT CONTROL REQUIREMENTS MINIMUM ESC REQUIREMENTS MINIMUM ESC REQUIREMENTS DURING CONSTRUCTION AFTER CONSTRUCTION ❑ Clearing Limits 0 Stabilize Exposed Surfaces 0 Cover Measures X❑ Remove and Restore Temporary ESC Facilities 0 Perimeter Protection 0 Clean and Remove All Silt and Debris Ensure � Traffic Area Stabilization Operation of Permanent Facilities X❑ Sediment Retention ❑ Flag Limits of SAO and open space preservation areas ❑ Surface Water Control ❑ Other 0 Dust Control 0 Construction Se uence Part 14 STORMWATER FACILITY DESCRIPTIONS Note: Include Facilit Summa and Sketch Flow Control T /Descri tion Water Qualit T e/Descri tion � Detention Vault ❑ Biofiltration ❑ Infiltration ❑ Wetpool ❑ Regional Facility ❑ Media Filtration ❑ Shared Facility ❑ Oil Control ❑ Small Site BMPs ❑ Spill Control ❑ Other ❑ Small Site BMPs ❑ Other 2005 Surface Water Design Manual I/1/OS 4 KING COUNTY, Vb'ASHINGTON, SURFACE WATER DESIGN MANUAL TECHNICAL INFORMATION REPORT (TIR) WORKSHEET Part 15 EASEMENTS/TRACTS Part 16 STRUCTURAL ANALYSIS ❑ Drainage Easement ❑ Cast in Place Vault ❑ Access Easement ❑ Retaining Wall ❑ Native Growth Protection Covenant ❑ Rockery>4' High ❑ Tract ❑ Structural on Steep Slope ❑ Other ❑ Other Part 17 SIGNATURE OF PROFESSIONAL ENGINEER I, or a civil engineer under my supervision, have visited the site. 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M,�'„� • >_�-! ��' � � � 01i�SI •.- .^ SE tt6tii S! � � NE 106ti"St �'�A"�r� _.__ �; � � � -- � ,�i f � ��,� -' }�. � �, ,� �:. a.c�. � ' , s '�1, �n r � �t i Ol+ ,{� i i•y� �„�� gy� .� 2s .k�. ,�� A� � �� � � 1�� ' !F S._9 q .�3 .�'�� .� �ry ' 6 � .. t: _ 't. � ��:, ..v�"''1?.�..��` _,* �' ��t� r U +�� ,�� �����, `'- q i'.� m.• �----'�. m '..r�„y-�`�"'5 ��� - � .. -� � �� -1 '�_..a. j / �tt: - �.� ��ea �l !`.C? i _ . >;.l� �- ,1. *1C�S.A p�. �R`�. ► �� q� Ne 8lh 51 ' � 1 . � I� , �., t �, �� � �� �! �` r t t ,.,,,1 r � I } + i � � �� �, 3 �;, � y f�+ � � R9 7 f'� �.� �. � �'�R�k r r�� � ��� NE 9tR P� � ' ,y ��, SE 1181h St -' � " . !� � , t����� �����';s�� �. -�`'� _� Fi ure 2 - Vicinit Ma Project: Hazen High School Classroom Addition Designed By: CMP Date: 11/0�/09 Project No. C090125-02 Client: DLR Group Checked By: JAJ Sheet 1 of 1 413 Pine Street • Suite 300 • Seattle, 1�VA • Phone (206) 343-0460 • F�ax (?Ob) 343-569] COUGHLIN PORTERLUNDEEN A CONSULTING STRUCTURAL AND CIVIL ENGINEERING CORPORATION _ I I � I =—�e-�d II Y// \ I � I /y I . /� � � � � / _ ��,I I ; � �y--- I� � � I � � `° � � ' -� / � � i � � '�` li r \ t� j ,, = I li i�; r � I I ! I � �� � � -I- � � 'I� � �;� � � � I�I � \\� / �,..lr-e,w,�+ � �� �� �� � '�"�1 - � / � .3 / �}�.. i�. _ I���. ✓ \ � / I .��` e � `� �� �,. ." � � �� � � ��� a =. Q ` � ,, � � � 3 � �. �� x ,. � ` � EXISIING � � � _�����` � c ��` �, ;�� � , .;� ,_;:� E ��' �' ' I BUILDING - ` — � � I►� — � =�;:<�' \ r—���I � `�, �\ ;�. � y � �� � iR' EXISTING _ � �I ��� � � � r l- � ss�'>� ; !i ' �� � � I � ` �'' ' ���� BUILDING = � I I � � I �'k:�: � � '� � I �.�; � ' �:�.; �� , ; I � �I � ��l � ' :�;:�'. � I'� I � ��f � � °� r . ; � I � �.�. I +�f'� � ��y�. 1 [; � � 1 I ( I'�I ! � � ,,� I ' '� I�I I I ' �� r °,�: � ., - ,i i /� I �I / ,.';+ �'�a_ �I�II �A � ',I� \ ��?a�� �..�a�.v c /�� �.� Itk � � LOT �,�; - y F��,�I , _� '�XI G V I I II�p , — _ r /�C � , ` — — '� ��� ��� �OF�' ' �E ' � / �� - . � � �.. �, � � , ��� ��� ,�.�..� =`=�., � BUI GS ,\ li; / / h ,l � i � , ,�,. � i �� -� � t t � � � � �,� � � , - �I � \ ` S - - Y\�, 1 � \,� Y� .� S � �/ ' I i�' !� s � � J, �r�� � 1 � ��i �`� l� / � � � j� v� � � ��� ; , i � ,. s { �„� � I � � � I) �II I � ` �� �.�.: t r..r'�;�4�: e'.y ,y' :t'�s:..+�'�`.i_.�.�--�-__ k. _ _ - I 1 � I I1 '1 '{,/ , C_�`� ~�,I � � O ��} ' - ,..� IiVf � , ll�� l� � � ��,,;� ,' � \ � � :� / :�� � _ �,� 'L:` � -��E �� � �� �,, —��_� —� '` � Ii � �\ �tJ� � L_��- - - - - _� — .•� � Y �r 111 11 \ \ — - - &" Y :, I/ � ;;, i x ��i �i_ � �� � �`` �. c � ���� � � I �-�� {z _ ' � �/ �� � ii � � I 2 ; �' ��� � ��� � �, , PROJECT r ; , X I � I, I � _ AREA LIMffS � 30 60 ,20 � � � I � � �i � � � 0 o i�� � i � (� � SCALE 1�=60' � � � � i �� Figure 3a - Existing S�e Cond�ions � � ��tisi!�� PROJECT: HAZEN I�MC#I SCHODL DESIGNED Bll: CIuP DATE: 06-14-09 PROJECT N0. 009-0015-42 CIIENT: DLR C�OUP CHECKED BY: SLG SHEET 1 OF 1 I 413 PINE STREET- SUITE 300 SEATTLE,WA 98101 P: 206/343-0460 F: 206/343-5691 COUGHLIN PORTERLUNDEEN A CONSULTING STRUCTURAL AND CIVIL ENGINEERING CORPORATION ; , ���� '\�I ` � �/ I � \ 'I �. � I I i �� � � �' � �� I `� 'I I \ � o I � � .� I �1 11 f ., � � � � � � �� � � \� , i � � ; ti r � = ` ' li� �i' I I � � �� � '� ; � i I � �� , I ; '; � � ' I� ! \� -- � � �� � a I ; ',, ' � ( c I �' I \ /��\, � I � � ����� � ; , 1 � - � � �� ` '� ��I EXISTING ,I , , Q I , �� �� � - � �� , , � � ` BUILDING , . - - ` � ' � ��I ' ` "a � � , � ; � � ( �- EXIS�ING _ ' '� � i � � ' BUILDING � � � � �, � /: � �/ �� . _ ` ' , � ✓ a I I' � \ , i p � - _ i I � / ���, '� � �� ;��,�� - - - i � ���� �� I , �� I \ � s— � G � , � „� �� DETENTION , .� � � �� � � �' V U T ' LOT , •� z � _ � A L , � , ��� ;� � ; _ - - _ i � , \ ;�' � ; - � i �� ' - i PROPOSED RAIN �' i�. m� - , ��. —T--, ,\ _ _ - � GAF�EN CTYP) - � �, � � \�{, - - . . •'`�, r _ - � - - \ _ " " i �k�, I�..�i � i, — r � � � I � �i j��� '�� '�'i''�� V� \ i �� i ■ �,. � � jl�l I I'i �I����11✓� � 'i \� � � � I I I�� '��( � � � � ��11�I � o A� �i ` / / \\\� � v / / i ���� ��, � , � /I� � / / / iI — � / / � a �' � g �; PROJECT o 30 60 ,Zo ` ' ' AREA LIMITS ���� r � , , � U � o � ;� SCALE 1A=60' � � � �� Figure 3b- Proposed Site Conditions , �r��1 � PROJECT: HAZBd I�(�I SCHOOL DESIGNED BY: CIuP DATE: 08-10-09 PROJECT N0. 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iiaii�i►iiiiiiii � � � � �� - u �s��r���ru.- � � � .�� ��� ��� �i��et�tiiiiiininn� � f'� � � �u�u��o�....0 � \ �.'---- /�� f � 1 - � . � • � • � � • � � � � � . . � � • -� �. 1 1 • ' • • • 1 ' 1 1 � � � - � C - � �1 1 1. ��.� 1. i � Retention/Detention Facility f Type of Facility: Detention Vault Facility Length: 99.89 ft Facility Width: 34.94 ft Detention Vault � Facility Area: 3988. sq. ft $ummary Effective Storage Depth: 6.00 ft Stage 0 Elevation: 100.00 ft IStorage Volume: 20930. cu. ft , Riser Head: 6.00 ft Riser Diameter: 12.00 inches � Number of orifices: 1 Full Head Pipe Orifice # Height Diameter Discharge Diameter (ft) (in) (CFS) (in) 1 1 0.00 0.50 0.017 � Top Notch Weir: None Outflow Rating Curve: None { Stage Elevation Storage Discharge Percolation (ft) (ft) (cu. ft) (ac-ft) (cfs) (cfs) , 0.00 100.00 0. 0.000 0.000 0.00 o.oi ioo.oi 35. 0.001 o.00i o.00 Racingtablefor 0.02 100.02 �o. 0.002 0.001 0.0o detention system 0.03 100.03 105. 0.002 0.001 0.00 0.09 100.09 140. 0.003 0.001 0.00 0.05 100.05 174. 0.004 0.001 0.00 0.15 100.15 523. 0.012 0.003 0.00 0.25 100.25 872. 0.020 0.003 0.00 0.35 100.35 1221. 0.028 0.004 0.00 0.95 100.45 1570. 0.036 0.005 0.00 ' 0.55 100.55 1919. 0.099 0.005 0.00 0.65 100.65 2268. 0.052 0.005 0.00 0.75 100.75 2616. 0.060 0.006 0.00 0.85 100.85 2965. 0.068 0.006 0.00 0.95 100.95 3319. 0.076 0.007 0.00 1.05 101.05 3663. 0.089 0.007 0.00 1.15 101.15 9012. 0.092 0.007 0.00 1.25 101.25 9361. 0.100 0.008 0.00 1.35 101.35 9709. 0.108 0.008 0.00 1.95 101.95 5058. 0.116 0.008 0.00 1.55 101.55 5907. 0.124 0.008 0.00 1.65 101.65 5756. 0.132 0.009 0.00 1.75 101.75 6105. 0.190 0.009 0.00 1.85 101.85 6954. 0.148 0.009 0.00 1.95 101.95 6802. 0.156 0.009 0.00 2.05 102.05 7151. 0.169 0.010 0.00 2.15 102.15 7500. 0.172 0.010 0.00 2.25 102.25 7899. 0.180 0.010 0.00 2.35 102.35 8198. 0.188 0.010 0.00 2.95 102.95 8597. 0.196 0.011 0.00 2.55 102.55 8895. 0.204 0.011 0.00 2.65 102.65 9249. 0.212 0.011 0.00 2.75 102.75 9593. 0.220 0.011 0.00 - � , 2.85 102.85 9992. 0.228 0.011 0.00 2. 95 102.95 10291. 0.236 0.012 0.00 � 3.05 103.05 10640. 0.299 0.012 0.00 , 3.15 103.15 10988. 0.252 0.012 0.00 � 3.25 103.25 11337. 0.260 0.012 0.00 3.35 103.35 11686. 0.268 0.012 0.00 3.95 103.45 12035. 0.276 0.013 O.CO ' 3.55 103.55 12389. 0.284 0.013 0.00 3.65 103.65 12733. 0.292 0.013 0.00 3.75 103_75 13082. 0.300 0.013 0.00 , 3.85 103.85 13930. 0.308 0.013 0.00 3.95 103.95 13779. 0.316 0.013 0.00 4.05 109.05 19128. 0.329 0.019 0.00 . 4.15 104.15 19477. 0.332 0.014 0.00 4.25 109.25 19826. 0.340 0.014 0.00 9.35 109.35 15175. 0.398 0.014 0.00 4.45 109.95 15523. 0.356 0.014 0.00 ' 9.55 109.55 15872. 0.369 0.014 0.00 9.65 109.65 16221. 0.372 0.015 0.00 9.75 109.75 16570. 0.380 0.015 0.00 � 4.85 109.85 16919. 0.388 0.015 0.00 � 4.95 109.95 17268. 0.396 0.015 0.00 5.05 105.05 17616. 0.904 0.015 0.00 5.15 105.15 17965. 0.912 0.015 O.CO ' S.25 105.25 18314. 0.920 0.016 0.00 5.35 105.35 18663. 0.928 0.016 0.00 5.45 105.45 19012. 0.936 0.016 0.00 � 5.55 105.55 19361. 0.944 0.016 0.00 5.65 105.65 19710. 0.952 0.016 0.00 5.75 105.75 20058. 0.960 0.016 0.00 • 5.85 105.85 20407. 0.468 0.016 0.00 5.95 105.95 20756. 0.476 0.017 0.00 6.00 106.00 20930. 0.480 0.017 0.00 6.10 106.10 21279. 0.489 0.325 0.00 Hyd Inflow Outflow Peak Storage Stage Elev (Cu-Ft) (Ac-Fti 1 0.34 0.01 4.04 104.09 14108. 0.3��i 2 0.32 0.01 3.01 103.01 10513. 0.291 Level-pool 3 0.31 0.01 4.29 104.29 19979. 0.399 4 0.27 0.01 1.06 101.06 3690. 0.085 routing summary 5 0.25 0.01 2.15 102.15 7509. 0.172 fordetention 6 0.23 0.01 2.10 102.10 7316. 0.168 system. 7 0.18 0.01 1.53 101.53 5352. 0.123 ' 8 0.16 0.01 1.05 101.05 3696. 0.084 ' �lyd R/D Facility Tributary Reservoir POC Outflow Outflow Inflow Inflow Target Calc 1 0.01 0.25 ******** ******* 0.26 2 0.01 0.23 ******** ******* 0.24 3 0.01 0.23 ******** ******* 0.24 Discharge 9 0.01 0.20 ******** ******* p.2p summary for Point 5 0.01 0.�8 ******** ******* o.i9 of Compliance 6 0.01 0.17 ******** ******* 0.18 7 0.01 0.13 ******** ******* 0.19 8 0.01 0.12 ******** ******* 0.12 - , i ; � , 0.013 13 10/08/81 21:00 0.011 2.58 34 1.99 0.330 � 0.011 28 1/08/83 6:00 0.011 2.56 35 1.95 0.310 0.009 94 11/24/83 9:00 0.011 2.55 36 1.91 0.291 0.009 43 11/11/84 9:00 0.010 2.37 37 1.37 0.271 0.012 29 1/19/86 10:00 0.010 2.32 38 1.33 0.251 0.013 11 11/27/86 1:00 0.010 2.27 39 1.30 0.231 0.010 40 12/10/87 8:00 0.010 2.22 40 1.27 0.211 � 0.009 42 11/25/88 1:00 0.010 2.17 41 1.29 0.191 0.019 9 1/09/90 22:00 0.009 1.97 92 1.21 0.171 0.019 7 11/25/90 0:00 0.009 1.96 93 1.18 0.151 �i 0.012 22 2/O1/92 0:00 0.009 1.95 99 1.15 0.131 I 0.009 97 1/26/93 5:00 0.009 1.88 95 1.12 0.111 0.008 50 12/11/93 11:00 0.009 1.83 96 1.10 0.091 0.013 16 12/27/99 21:00 0.009 1.63 97 1.08 0.071 0.015 3 2/09/96 12:00 0.008 1.97 98 1.05 0.051 0.019 6 1/03/97 3:00 0.008 1.97 99 1.03 0.031 Calculated o.oio 9i i/25/gs o:oo o.00s i.qi so i.oi o.oil �00- ear WSE M Computed Peaks 0.017 5. 93 100.00 0.990 Y Computed Peaks 0.016 5.86 50.00 0.980 Computed Peaks 0.015 5.19 25.00 0.960 Computed Peaks 0.019 9.58 10.00 0.900 Calculated Peak Computed Peaks 0.019 9.56 8.00 0.875 Flow and Peak Computed Peaks 0.013 3.98 5.00 0.800 Computed Peaks 0.012 2.90 2.00 0.500 Stagefor ' Computed Peaks 0.010 2.36 1.30 0.231 Detention System Flow Frequency Analysis LogPearson III Coefficients Time Series File:dsout.tsf Mean= -0.836 StdDev= 0.106 Project Location:Sea-Tac Skew= 0.395 ---Annual Peak Flow Rates--- -----Flow Frequency Analysis------- Flow Rate Rank Time of Peak - - Peaks - - Rank Return Prob {CFS) (CFS) Period 0.150 21 2/16/99 21:00 0.260 1 89.50 0.989 Flow Frequency 0.243 2 3/03/50 16:00 0.243 2 32.13 0.969 0.156 20 2/09/51 2:00 0.240 3 19.58 0.999 analysis for Point 0.119 40 10/15/51 13:00 0.235 9 19.08 0.929 of Compliance. 0.112 47 3/29/53 15:00 0.203 5 10.99 0.909 0.140 26 12/19/53 19:00 0.203 6 9.01 0.889 0.196 23 11/25/59 2:00 0.188 7 7.64 0.869 0.141 25 11/18/55 15:00 0.166 8 6.63 0.899 0.166 15 12/09/56 14:00 0.177 9 5.86 0.829 0. 146 22 12/25/57 16:00 0.176 10 5.24 0.809 0.113 46 11/18/58 13:00 0.173 11 4.75 0.789 0.193 29 11/20/59 5:00 0.170 12 9.34 0.769 0.128 39 2/14/61 21:00 0.169 13 3.99 0.799 0.123 39 11/22/61 2:00 0.167 14 3.70 0.729 0.127 35 12/15/62 2:00 0.166 15 3.44 0.709 0.190 27 12/31/63 23:00 0.164 16 3.22 0.690 0.126 37 12/21/69 9:00 0.163 17 3.03 0.670 0.130 33 1/05/66 16:00 0.163 18 2.65 0.650 0.188 7 11/13/66 19:00 0.158 19 2.70 0.630 0.203 6 8/24/68 16:00 0.156 20 2.56 0.610 0.117 91 12/03/68 16:00 0.150 21 2.94 0.590 I 0.127 36 1/13/70 22:00 0.146 22 2.32 0.5'70 0.129 38 12/06/70 8:00 0.146 23 2.22 0.550 0.186 8 2/27/72 7:00 0.143 24 2.13 0.530 0 .115 95 1/13/73 2 :O�J 0.191 25 2.04 0.510 � � 0.136 28 11/28/73 9:00 0.190 26 1.96 0.490 � 0.176 10 12/26/79 23:00 0.190 27 1.89 0.470 ' 0.117 42 12/02/75 20:00 0.136 28 1.82 0.950 ', � 0.136 29 8/26/77 2:00 0.136 29 1.75 0.930 ,I 0.177 9 9/17/78 2:00 0.135 30 1.70 0.910 0.158 19 9/08/79 15:00 0.132 31 1.69 0.390 0.169 16 12/19/79 21:00 0.131 32 1.59 0.370 � 0.170 12 11/21/80 11:00 0.130 33 1.59 0.350 I r f 0.235 9 10/06/81 0:00 0.128 34 1.99 0.330 0.167 19 10/28/82 16:00 0.127 35 1.95 0.310 � 0.135 30 1/03/89 1:00 0.127 36 1.91 0.291 � 0.116 43 6/06/85 22:00 0.126 37 1.37 0.271 0.163 17 1/18/86 16:00 0.124 38 1.33 0.251 0.203 5 10/26/86 0:00 0.123 39 1.30 0.231 0.092 49 11/11/87 0:00 0.119 40 1.27 0.211 0.116 49 8/21/89 17:00 0.117 41 1.29 0.191 0.260 1 1/09/90 6:00 0.117 42 1.21 0.171 ! 0.240 3 11/29/90 8:00 0.116 43 1.18 0.151 0.132 31 1/27/92 15:00 0.116 49 1.15 0.131 0.087 50 11/O1/92 16:00 0.115 95 1.12 0.111 0.100 98 11/30/93 22:00 0.113 46 1.10 0.091 0.131 32 11/30/99 9:00 0.112 47 1.08 0.071 0.173 11 2/08/96 10:00 0.100 48 1.05 0.051 0.163 18 1/02/97 6:00 0.092 49 1.03 0.031 0.169 13 10/09/97 15:00 0.087 SO 1.01 0.011 computed Peaks 0.275 100.00 0.990 Calculated Peak Computed Peaks 0.253 50.00 0.980 Flow and Peak Computed Peaks 0.230 25.00 0.960 $� e for Point of Computed Peaks 0.201 10.00 0.900 g Computed Peaks 0.195 8.00 0.875 COmPIianCe Computed Peaks 0.178 5.00 0.600 Computed Peaks 0.199 2.00 0.500 Computed Peaks 0.121 1.30 0.231 Flow Duration from Time Series File:rdout.tsf Cutoff Count Frequency CDF Exceedence Probability CFS o % o 0 .000 6778 1.597 1.547 98.453 0.985E+00 Exceedence 0.001 153969 35.153 36.700 63.300 0.633E+00 0.001 38523 8.795 95.495 54.505 0.545E+00 Probability 0.001 19733 3.369 48.859 51.191 0.511E+00 Analysisfor �_002 11293 2.578 51.437 98.563 0.986E+00 Detention System 0.002 8911 2.039 53.472 96.528 0.465E+00 0.003 7166 1.636 55.108 44.892 0.949E+00 �I 0.003 34649 7.911 63.019 36.981 0.370E+00 I 0 .009 9999 2.283 65.302 34.698 0.347E+00 I 0.004 8366 1.910 67.212 32.788 0.328E+00 I'� 0.009 7552 1.729 68.936 31.064 0.311E+00 I 0.005 6789 1.550 70.486 29.519 0.295E+00 ��I 0.005 31918 7.173 77.659 22.391 0.223E+00 v.006 5203 1.188 78.847 21.153 0.212E+00 C.006 19923 3.293 82.140 17.860 0.179E+00 0.007 3701 0.845 82.985 17.015 0.170E+00 0.007 3651 0.839 83.618 16.182 0.162E+00 C.007 16791 3.839 87.652 12.348 0.123E+00 C.008 2640 0.603 88.255 11 .795 0.117E+00 C.008 1770C 4.C41 9�.296 7 .�'G4 0 .�70E-C1 i 0.009 1830 0.918 92.713 7.287 0.729E-01 i 0.009 11265 2.572 95.285 9.715 0.971E-01 0.010 988 0.226 95.511 4.989 0.499E-01 0.010 956 0.218 95.729 9.271 0.927E-01 E 0.010 6833 1.560 97.289 2.711 0.271E-01 0.011 699 0.158 97.448 2.552 0.255E-01 0.011 5192 1.179 98.622 1.376 0.138E-01 ; 0.012 339 0.076 98.698 1.302 0.130E-01 � 0.012 2809 0.691 99.339 0.661 0.661E-02 0.012 243 0.055 99.395 0.605 0.605E-02 � 0.013 206 0.047 99.442 0.556 0.558E-02 ; 0.013 1915 0.323 99.765 0.235 0.235E-02 0.014 66 0.015 99.780 0.220 0.220E-02 0.014 580 0.132 99.912 0.088 0.877E-03 1 0.015 32 0.007 99.920 0.080 0.809E-03 0.015 29 0.007 99.926 0.074 0. 737E-03 � Flow Duration from Time Series File:dsout.tsf Cutoff Count Frequency CDF Exceedence Probability CFS o o g I, I 0.009 267615 61.099 61.099 38.901 0.389E+00 Exceedence � 0.011 116970 26.591 87.691 12.309 0.123E+00 0.018 30965 7.070 99.760 5.240 0.524E-01 Probability 0.026 9293 2.110 96.871 3.129 0.313E-01 Analysis for Point � 0.033 9929 1.125 97.996 2.009 0.200E-01 of Compliance 0.090 2953 0.679 98.670 1 .330 0.133E-01 0.097 1900 0.434 99.104 0.896 0.896E-02 0.055 1205 0.275 99.379 0.621 0. 621E-02 ' 0.062 826 0.189 99.568 0.932 0.432E-02 0.069 540 0.123 99.691 0.309 0. 309E-02 0.077 386 0.088 99.779 0.221 0.221E-0� 0.084 268 0.061 99.840 0.160 0.160E-02 0.091 199 0.045 99.886 0.114 0.114E-02 0.099 192 0.032 99.918 0.082 0.820E-03 0.106 92 0.021 99.939 0.061 0.610E-03 0.113 68 0.016 99.955 0.045 0.959E-03 0.120 99 0.010 99.965 0.035 0.359E-03 0.128 37 0.008 99.973 0.027 0.269E-03 0.135 28 0.006 99.979 0.021 0.205E-03 0.142 23 0.005 99.985 0.015 0.153E-03 , 0.150 18 0.004 99.989 0.011 0.112E-03 0.157 12 0.003 99.992 0.008 0.895E-09 0.169 5 0.001 99.993 0.00� 0.731E-09 0. 171 7 0.002 99.999 0.006 0.571E-09 0.179 5 0.001 99.995 0.005 0.957E-09 0.186 5 0.001 99.997 0.003 0.392E-09 0.193 4 0.001 99.997 0.003 0.251E-09 0.201 1 0.000 99.998 0.002 0.228E-09 0.208 2 0.000 99.998 0.002 0.183E-04 0.215 1 0.000 99.998 0.002 0.160E-04 0.223 0 0.000 99.998 0.002 0.160E-04 0.230 2 0.000 99.999 0.001 0.119E-04 0.237 2 0.000 99.999 0.001 0.685E-05 0.294 2 0.000 100.000 0.000 0.228E-05 ' 0.252 0 0.000 100.000 0.000 0.228E-OS 0.259 0 0.000 100.000 0.000 0.228E-05 Duration Comparison Anaylsis f � f f Base File: existing.tsf New File: dsout.tsf Cutoff Units: Discharge in CFS ! -----Fraction of Time----- ---------Check of Tolerance------- Cutoff Base New �Change Probability Base New %Change 0.073 I 0.30E-02 0.27E-02 -11.0 I 0.30E-02 0.073 0.070 -3.6 Developed ` 0.089 I 0.16E-02 0.13E-02 -19.9 � 0.16E-02 0.089 0.089 -5.3 flOw 0.105 I 0.83E-03 0.65E-03 -21.7 I 0.83E-03 0.105 0.098 -6.5 durationsare 0.121 I 0.99E-03 0.35E-03 -28.0 I 0.49E-03 0.121 0.111 -8.1 i 0.137 I 0.29E-03 0.18E-03 -37.3 I 0.29E-03 0.137 0.126 -7.g �essthanthe ` 0.153 I 0.15E-03 O.10E-03 -33.3 I 0.15E-03 0.153 0.193 -6.7 existing flow 0.170 I 0.89E-09 0.62E-04 -30.8 I 0.89E-09 0.170 0.156 -7-9 durations. � 0.186 I 0.53E-09 0.34E-09 -39.8 I 0.53E-04 0.186 0.176 -5•9 Therefore 0.202 I 0.25E-09 0.23E-09 -9.1 I 0.25E-04 0.202 0.199 -1.2 0.218 I 0.18E-09 0.16E-09 -12.5 � 0.18E-04 0.218 0.208 -4.9 the storm � 0.234 I 0.19E-09 0.91E-05 -33.3 I 0.14E-09 0.239 0.229 -2.9 water � 0.250 I 0.19E-09 0.23E-05 -83.3 I 0.14E-04 0.250 0.229 -8.7 requiremenu 0.266 I 0.23E-05 O.00E+00 -100.0 � 0.23E-OS 0.266 0.260 -2.5 0.283 I 0.23E-05 O.00E+00 -100.0 I 0.23E-OS 0.283 0.260 -g.p are met. � Maximum positive excursion = 0.001 cfs ( 0.2$) Compare occurring at 0.228 cfs on the Base Data:existing.tsf Fjcceedence 4 and at 0.229 cfs on the New Data:dsout.tsf betweenthe Maximum negative excursion = 0.028 cfs (-10.90) exiStingCOndition5 occurring at 0.259 cfs on the Base Data:existing.tsf andthe developed and at 0.231 cfs on the New Data:dsout.tsf conditions at the point of � compliance. � � � � � N _ _-- - -- - - ---- --- — � rdout.dur � dsout.dur • �, existing.DUR �=' v N . _ --- o ,� — - ! ��! � '. O N ----------- --_----------- �' '- --------------------------- -- ---- � �' Existing Flow �►._ _ • Duration Curve y � �'� ,, ^ �----- — --------- __ -_, — — -- ---------------�—��_..----- cn o _ � �, � ,r, U '+� _ � a� ',� ', m m �� L U \y� ' fn �y .. � �- ---- ---- \. -� ��'2 � Developed Point of �. - Compliance Flow �►, '-'. Duration Curve ''` �� �, ao �:< � - - -------- o 'R',. ��,;� .�\ � �� v � , o- -----------------..___ ---- ---__.-- - --__----_------- �. 0 '� Vault Discharge Flow �, R _ __ Duration Curve � ,.._ --_, ,i ; _ _ . o > _ , _..+__ -_ , o _ _ -- ,�.:», � � '�::_.,,�., 10 -6 � I 1� 5 10 _4 101-s 10 �2 10 -� 10° Drnh�hilifii CvnnnrJnnn� � i � vault.exc KCRTS Program. . .File Directory: C:\KC_SWDM\KC_DATA\ [C] CREATE a new Time Series � ST 1.23 0.00 0.000000 Till Forest 0.00 0.00 0.000000 Till Pasture 0.00 0.00 0.000000 Ti 11 Grass Existing Site Area 0.00 0.00 0.000000 outwash Forest 0.00 0.00 0.000000 outwash Pasture 0.00 0.00 0.000000 outwash Grass 0.00 0.00 0.000000 wetland 0. 51 0.00 0.000000 Impervious ' existing.tsf F 1.00000 T [C] CREATE a new Time Series ST 0.00 0.00 0.000000 Till Forest � 0.00 0.00 0.000000 Till Pasture 0.29 0.00 0.000000 Ti 11 Grass Developed Site Area 0.00 0.00 0.000000 outwash Forest 0.00 0.00 0.000000 outwash Pasture Dischargingto 0.00 0.00 0.000000 outwash Grass Detention System 0.04 0.00 0.000000 wetland 0.67 0.00 0.000000 Impervious detention.tsf F 1.00000 T [C] CREATE a new Time Series � ST ' 0.00 0.00 0.000000 Till Forest ; 0.00 0.00 0.000000 Ti 11 Pasture Develo ed Site Area ; 0.26 0.00 0.000000 Till Grass P 0.00 0.00 0.000000 outwash Forest Bypassing Detention 0.00 0.00 0.000000 outwash Pasture S stem r 0.00 0.00 0.000000 outwash Grass Y 0.00 0.00 0.000000 wetland 0.48 0.00 0.000000 Impervious bypass.tsf F 1.00000 T [T] Enter the Analysis Too�s Module [P] Compute PEAKS and Flow Frequencies existing.tsf exi sti ng.pks Calculate peak flows [P] Compute PEAKS and Flow Frequencies of existing area, area detention.tsf detenti on.pks discharging to [P] Compute PEAKS and Flow Frequencies detention, and bypass.tsf by ass.pks bypass areas. [�]� Compute Flow DURATION and Exceedence Calculate existing exi sti ng.tsf flow durations. existing.DUR F F 36 ' 0.557000E-02 0.730000E-01 [R] RETURN t� Previous Menu Page 1 , vault.exc [F] Size a Retention/Detention FACILITY Manual �esi gn Route area through vault.rdf detention system. 5 Route Time Series ' 0 Return to Main Menu Add bypass to [F] Size a Retention/Detention FACILITY detentionsystem Manual Design vault.rdf discharge. ` 5 Route Time SerieS 0 Return to Main Menu � [T] Enter the Analysis TooLS Module ! [C] COMPARE Flow Durations existing.tsf dsout.tsf compare.prn F Compare peak flows 0.730000E-01 and flow durations of 0.283000 14 existing time series [P] Compute PEAKS and Flow Frequencies with point of dsout.tsf doust.pks compliance time [R] RETURN to Previous Menu series. [X] eXit KCRTS Program Page 2 COUGHLIN PORTERLVNDEEN STRUCTURAL • CIVIL • SEISMIC ENGINEERING � /�' � � ' '� 1 : � = � � , �; ���� . _ _ c;A, �� � I I � �I � � ', �! ' �� ' � , � } i � � �� ���� �� � � � � , � ; , ,� � ; . . � � ; ��, ........... � ►. � : �� � ,�, � �,�j � t : EX N �B 10 < < + �, i � � � , ` � �� � � I ; � /, � ; � �� ; � �� ; �� ���� �� , � ; , � - � i �i� � — � i + �, ; i � � � � �� . � I �; , � , ,� / . j �� t ,�-; , , I, �i I�' I / % ,, 1 \I � / � � �� � i I ✓ , � � j �\� �' % I - � ; � I� � Q i �,� / �a. . ' 1 �I II I � 1,1 \\�, t � ' \\\\ � Ili x �� � � � iI � \\I =j r�l` � i l �� � \ � I �`� `� � I �, � I ��� ' � `a � � I �, ; � �; I � , , , + � � �� ; ; T i . , I ' i �— � ��;`' ` � � l I � `' CB fi � � _ _ . � �,i� � . , � , ; � I � �� �� � � , �,\ }} �' � , � � � � � i � � I I 1 _ — , � � ��1 1 ^ � _ � \ � '\ -- I a,` 'I��11 �� j j f , - "'— � � \ �� . � �p� ;I� I �� !;(C�i _�'� \ � � � , ,, �, �`,� ,r, � . � � �. � ���i o ��� �� i , .� � � i ��� ,' � i, I�I,�`�i� � � �' \ � , � DIRECT TO DEfEM10N e , ; I i I � ; �� � ;� � ��� ����'� � , _ � �. I', , 3 �� ,�� �} � `�� . / / � � � ,� �� � � ��� �� �� � S / ����_�� �� ���:; - � �c � / I / \��� 1 ����; g � � I � � . z � , ;V; ; � ,i �� � � _, i T/ r u I/ I v li �% ,� � ` I"=50' � � ; �' —" CB Areas , f-� �I ,�,�/ � I, Project Hazen HS Classroom Addition Designed By: GMP Date: I I-05-09 Project No: C090125-02 Client: DLR Group Checked By:JAJ Sheet: I of I 413 PINE STREET � SUITE 300 • SEATTLE,WA 98101 � P:206/343-0460 � F:206/343-5691 www.cplinc.com Hazen Hi�h School Classroom Addition f .. � Draina e Sub-Basin Areas Sub- Totai Composite AsphalUConcrete Roof Grass � Basin Area� C Value Area Area Area � (Acres) (Sq.Ft),C=0.90 (Sq.Fr.),C=0.90 (Sq.Ft),C=0.25 4 CB 102 O:U8 0.30 276 0 3362 ' EX N CB� O.J 1 0:90 1075 0 3705 CB 9 O:l l 0:41 1 i25 0 3524 CB S 0.14 0:58 3185 0 3055 CB 7 O:OU . O:f�O 0 0 0 CB 6 0:3D 0.67 1070 7427 4552 CB 5 0:26 0.5� 3670 0 3373 CB 4 080 O.Q� 0 0 0 CB 3 0:00 0.00 0 0 0 CB 2 6:OD U.(H1 0 0 0 CB 1 O:f10 U:QO 0 0 0 EX W CB D:00 U.�O 0 0 0 Not Detained Q.55 4.7� 19960 0 4139 Area West Direct to 0.28 fl.9li 0 ]2208 0 Detention Torals I.,74 303b1 19635 2S71� ' Notes: �These sub-basin areas are based on developed site conditions. zThese sub-basin azeas are not detained. Hazen High School Classroom Addition Conveyance Analysis 12115l2009 F CONVEYANCE SYSTEM ANALl'SIS AND SIZING TABLE US1NG THE RATIONAL METHOD Sub Area C C*A Sum Tc i(R) I(R) Q(R) - Pipe Typ. Slope Q(F) V V L Tt %d/D Basin (ac) C*A (min.) (c.f.s.) (in.) n (ft.ft.) (pipe (pipe (at (ft.) (min.) From To Number full) full) Q(R)) CB 102 EX N CB2 CB 102 0.08 030 0.02 0.02 6.3 0.80 2.49 0.06 6 0.013 0.50% 0.40 2.04 1.46 50 0.6 27.00% EX N CB2 Out EX N CB2 0.11 0.40 0.04 0.07 6.9 0.76 236 0.16 4 0.013 0.50% O.l 3 1.49 1.85 50 0.5 99.90% CB 9 CB 7 CB 9 0.1 l 0.41 0.04 0.04 6.3 0.80 2.49 0.11 8 0.013 2.50% 1.92 5.50 3.01 35 0.2 16.00% CB 8 CB 7 CB 8 0.14 0.58 0.08 0.08 63 0.80 2.49 0.21 8 0.013 2.10% 1.76 5.04 3.43 42 0.2 23.00% CB 7 Detention CB 7 0.00 0.00 0.00 0.13 6.5 0.79 2.44 031 8 0.013 2.00% 1.71 4.90 3.68 27 0.1 29.00% CB 6 CB 4 CB 6 030 0.67 0.20 0.20 6.3 0.80 2.49 0.50 8 0.013 2.60% 1.95 5.59 4.62 46 0.2 35.00% CB 5 CB 4 CB 5 0.16 0.59 O.10 0.10 63 0.80 2.49 0.24 8 0.013 3.10% 2.13 6.10 4.17 39 02 22.00% CB 4 Detention CB 4 0.00 0.00 0.00 030 6.5 0.79 2.45 0.73 8 0.013 2.00% 1.71 4.90 4.58 l 1 0.0 46.50% ' Detention CB 3 Detention 0.00 0.00 0.00 0.00 63 0.80 2.49 O.U7 12 O.Ol3 0.50% 2.53 3.22 1.71 90 0.9 10.00% CB 3 CB 2 CB 3 0.00 0.00 0.00 0.00 7.2 0.74 2.29 0.07 12 0.013 0.60% 2.77 3.53 1.71 25 0.2 10.00% CB 2 CB 1 CB 2 0.00 0.00 0.00 0.00 7.4 0.72 224 0.{1'7 12 0.013 0.50% 2.53 3.22 1.71 131 13 10.00% CB 1 EX W CB CB 1 a.00 0.00 0.00 0.00 8.7 0.65 2.02 0.07 12 O.Ol3 0.50% 2.53 3.22 1.71 34 03 10.00% � Project: Hazen Hig Sc oo C BRcrn�u�AC� ition R= � P(R)= �1.Q Calcs by: CMP Job No: C09-0125-02 Location: Kin Coun , WA Date: 12!15/2009 Pa e l e Hazen High School Classroom Addition Conveyance Analysis- 25 Year 12/15/2009 Backwater Analysis Table Mannings Coefficient 0.011 The difference between the water elevation(Headwater)and Hazen High School Classroom Addition the RtM should bc geater�han o.0 feec Pmposed Site Conditions Location Q L Pipe TYP Outlef Inlet Barrel Barrel Velocity Excel Critical TW Friction HGL Entry Entry Exit Outlet Headwater Iniet Approach $end Bend Junct�on Headwater Rim Elev. O.K.? Downstream Upstream (cfs) (F� Diam(in), n F1ev �Iev Area Velocity Head Check Depth Elev Loss E�¢v Coef Loss Loss Control Depth Control Head Coefficient Loss - Loss Elevation nrnfterence Q L D n ELEV O ELEV 1 A V H dc TW Floss HGL Ke ENLoss Eloss Eloc HW/D Elic Hv IL"b BI Junc 1iVV �Lim HGL EXWCB CB7 0.07 34 12 Qall 454_59 454.74 0.785 0.089 0.000 7.i5 029 455.55 0.00 455.74 03 0.00 0.00 455J4 0.29 455.03 0.000 0 0.00 0� 455.94 454 8.06 yes CB 1 CB 2 0.07 131 1� 0_011 d54_74 455.A 0.785 0.089 0.000 7.14 029 455.94 0.00 456 40 0:5 0_00 0.00 456.40 0.29 455.69 0.000 134 0.00 0 456.40 457.05 ]Ob5 yes CB 2 CB 3 0.07 23 12 0_O!1 453.4 A55.55 0.785 0.069 0.000 7.14 0.29 456.40 0.00 456.55 0.5 0.00 0.00 456.55 0.29 455.84 0.000 �34 0.00 0 456.55 456:7 10.15 ycs CB 3 Detention 0.07 90 14 0.0]1 455.55 456 0.765 0.089 0.000 7.14 0.29 456.55 0.00 457.00 0:5 0.00 0.00 457.00 0.29 456.29 0.000 0 0.00 0 45200 451 4.00 ycs Detention CB 4 0.73 I1 8 D.O11 460.55 46Q:77 0.349 2.087 0.068 1.00 0.40 461.00 0.03 461.44 D.5 0.03 0.07 461.54 0.63 461.19 0.068 9 0.00 0.2 461.81 467 5.19 ycs CB 4 CB S 024 39 8 0.011 460.77 461.98 0349 0.680 0.007 1.00 022 461.81 OA1 462.65 U.5 0.00 OA1 462.66 0.33 462.�0 0.007 1.34 0.01 0 462.67 465.15 2.48 ycs CB 4 CB 6 O.SO 46 S 0.011 4g0.77 461.48 0.349 1.440 0.032 I.00 033 461.81 0.06 462b5 0.5 0.02 0.03 462.69 0.51 462.32 0.032 1.34 0.04 0 . 462.77 465.15 238 yes Dctention CB 7 031 2'7 8 0.011 46fl.35 461.09 0349 0.887 OAl2 l 00 026 46I.00 0.01 461.76 0.5 0.01 0.01 461.7? 039 461.35 0.012 0 0.00 0.2 461.99 4bG 4.01 yes CB 7 CB 8 021 43 8 DAl l 461.09 461.98 0.349 0.595 0.005 I 00 021 461.99 0.0] 462.65 OS 0.00 0.01 462.65 031 462.19 0.005 1.34 0.0] 0 462b7 465.t3 2.48 yes CB 7 CB 9 O.I I 35 8 0.011 46l.09 4b1:98 0.349 0.310 0.001 L00 0.15 461.99 0.00 462.65 0;3 0.00 0.00 462b5 0.22 462.13 0.001 1.34 0.00 0 462.65 463.13 2.50 yes Out E7C N CB 0.16 50 4 0.011 464A5 464.3 0.087 L848 0.053 0 79 0.20 464.80 0.25 465.05 0:5 0.03 OAS 465J 3 0.63 464.51 0.05? 0 0.00 0 46519 4b5.27 0.08 ye> EX N CB CB]0 0.06 50 b O.011 4643 4b4:d5 0.196 0317 0.00? LUO 0.12 465.I9 0.00 465.19 0.5 0.00 0.00 465.�9 0.25 464.57 0.002 1.34 0.00 0 46520 '456.15 0.95 yes Hazen High School Classroom Add�tion Backwater Analysis-25-Year 12l15r2009 areas.exc KCRTS Program. . .File Directory: C:\KC_SWDM\KC_DATA\ [C] CREATE a new Time Series ST 0.00 0.00 0.000000 Till Forest 0.00 0.00 0.000000 Till Pasture 0. 59 0.00 0.000000 Till Grass 0.00 0.00 0.000000 outwash Forest 0.00 0.00 0.000000 outwash Pasture � 0.00 0.00 0.000000 Outwash Grass 0.00 0.00 0.000000 wetland f 1.15 0.00 0.000000 Impervious j TESC.tSf F 1.00000 T ` [T] Enter the Analysis TOOLS Module [P] Compute PEAKS and Flow Frequencies tesc.tsf TESC.pks [R] RETURN to Previous Menu [X] eXit K�RTS Program Page 1 TESC.pkS Flow Frequency Analysis �ogPearson III Coefficients Time Series File:tesc.tsf Mean= -0.481 StdDev= 0.107 Project �ocation:sea-Tac Skew= 0.450 ---Annual Peak Flow Rates--- -----Flow Frequency Analysis------- Flow Rate Rank Time of Peak - - Peaks - - Rank Return Prob I (CFS) (CFS) Period � 0.338 21 2/16/49 21:00 0. 589 1 89.50 0.989 II 0.553 2 3/03/50 16:00 0. 553 2 32.13 0.969 i ' 0.343 20 2/09/51 2:00 0. 541 3 19.58 0.949 '� 0.273 41 10/15/51 13:00 0. 539 4 14.08 0.929 ' 0.260 44 3/24/53 15:00 0.473 5 10.99 0.909 : 0.315 27 12/19/53 19:00 0.473 6 9.01 0.889 0.326 23 11/25/54 2:00 0.434 7 7.64 0.869 0.319 24 11/18/55 15:00 0.421 8 6.63 0.849 0.375 15 12/09/56 14:00 0.420 9 5.86 0.829 0.332 22 12/25/57 16:00 0.399 10 5.24 0.809 0.248 47 11/18/58 13:00 0.389 11 4.75 0.789 0.318 25 11/20/59 5:00 0.387 12 4.34 0.769 0.283 36 2/14/61 21:00 0.386 13 3.99 0.749 0.281 38 11/22/61 2:00 0.382 14 3.70 0.729 0.282 37 12/15/62 2:00 0.375 15 3.44 0.709 0.316 26 12/31/63 23:00 0.370 16 3.22 0.690 0.284 35 12/21/64 4:00 0.368 17 3.03 0.670 � 0.285 34 1/05/66 16:00 0.364 18 2.85 0.650 0.434 7 11/13/66 19:00 0.356 19 2.70 0.630 : 0.473 5 8/24/68 16:00 0.343 20 2.56 0.610 0.260 43 12/03/68 16:00 0.338 21 2.44 0.590 0.288 33 1/13/70 22:00 0.332 22 2.32 0.570 0.274 40 12/06/70 8:00 0.326 23 2.22 0.550 0.421 8 2/27/72 7:00 0.319 24 2.13 0.530 0.254 46 1/13/73 2:00 0.318 25 2.04 0.510 0.304 30 11/28/73 9:00 0.316 26 1.96 0.490 0.399 10 12/26/74 23:00 0.315 27 1.89 0.470 0.259 45 12/02/75 20:00 0.306 28 1.82 0.450 0.306 28 8/Z6/77 2:00 0.305 29 1.75 0.430 0.420 9 9/17/78 2:00 0.304 30 1.70 0.410 0.370 16 9/08/79 15:00 0.298 31 1.64 0.390 0.368 17 12/14/79 21:00 0.298 32 1.59 0.370 0.389 11 11/21/80 11:00 0.288 33 1.54 0.350 0.539 4 10/06/81 0:00 0.285 34 1.49 0.330 0.386 13 10/28/82 16:00 0.284 35 1.45 0.310 0.305 29 1/03/84 1:00 0.283 36 1.41 0.291 0.264 42 6/06/85 22:00 0.282 37 1.37 0.271 0.364 18 1/18/86 16:00 0.281 38 1.33 0.251 0.473 6 10/26/86 0:00 0.275 39 1.30 0.231 0.212 49 11/11/87 0:00 0.274 40 1.27 0.211 0.275 39 8/21/89 17:00 0.273 41 1.24 0.191 0.589 1 1/09/90 6:00 0.264 42 1.21 0.171 0.541 3 11/24/90 8:00 0.260 43 1.18 0.151 0.298 32 1/27/92 15:00 0.260 44 1.15 0.131 0.197 SO 11/Ol/92 16:00 0.259 45 1.12 0.111 0.228 48 11/30/93 22:00 0.254 46 1.10 0.091 0.298 31 11/30/94 4:00 0.248 47 1.08 0.071 0.382 14 2/08/96 10:00 0.228 48 1.05 0.051 0.356 19 1/02/97 6:00 0.212 49 1.03 0.031 0.387 12 10/04/97 15:00 0.197 SO 1.01 0.011 computed Peaks 0.636 100.00 0.990 Computed Peaks 0.581 50.00 0.980 Computed Peaks �.528 25.00 0.960 computed Peaks 0.458 10.00 0.900 Computed Peaks 0.444 8.00 0.875 Computed Peaks 0.404 5.00 0.800 Page 1 COUGHLINPORTERLUNDEEN I! A CONSULTING STRUCTURAL AND CIVIL ENGINEERING CORPORATION I , Hazen High School Classroom Addition and Renovation Temporary Construction Storage , Storage Volume based on King County Storm Water Design Manual,Appendix D,D3.5(2005) * the volume is based on a minimum pond depth of 2'-this depth does not include the minimum sediment storage volume or freeboard � i 2 S.A.= Q x F.S. Vsed f V = S.A.x D r where: � S.A.= Minimum allowable top surface area of pond(ft 1) Qz= Design Peak Flow Rate(cfs) � V�d= Approximate Particle Settling Velocity=0.00096 ft/s F.S.= Factor of safety=2 D= Minimum pond depth=2 ft V�= Minimum Required Storage Volume(cn Site TESC Storage Developed 2 year peak(&om KCTRS. See following sheets): 0.73 cfs ' � ` S.A. = 0.73 x 2 = 1,521 ft 2 0.00096 ' Vr = 1,521 x 2 = 3,042 ft 3 � Minimum Required Storage Volume= 3.042 ft3=22.755 gallon. Volume Provided =36,200 �all�ns ' I � F Project: Hazen High School Classroom Addition Designed By: CMP Date 12/15/09 Project No. C090125-02 Client: DLR Group Checked By: JAJ Sheet 413 Pine Street Suite 300� Seattle,WA 98101 � P:206l343-0460• F:2061343-5691 APPENDIX C Geotechnical Report COUGHLIN POKTER LUNDEEN Hazen HS Classroom Addition �''=`�"'''` - �"� - 'u�t��`' - - f� , s Geotechnical Engineering Associated Earth Sciences, I11C. .�.i:: ����1"G�lll?GJ alfef Z� �BG3'�1'Of��l''l/ICG' - �.�-�.�-- ✓ _� � �. � ...��,.t -�-�, i _.. f �� _ .� . . �. " ,x_.� r . _ � �i __- � ��� Subsurface Exploration, Geologic Hazards, and Preliminary Geotechnical Engineering Report Water Resources �r"`�- =�;�V� S`��� . HAZEN HIGH SCHOOL t<, ��-;; . "j-.- .��f::Y�J -�. - BUILDING ADDITION �� �:�;, . _.;:�; ���:,_ Renton, Washington Environmental Assessments and Prepared for Remediation . ;, Renton School District � ��;: r =- � . - �- ��� - � ` � ,;�f ` Project No. KE080762B -_-- _ _ .,.;,f. ,. - ° May 15, 2009 Sustainable Development Services _ ; . :f- _�- �- :_ - t - ^, .�.- - � _ � .rr �_ ' - -... �-.: . , ';�. " ... '�� Geologic Assessments Associated Farth Sciences, Inc. � �� . F,:.."- � _ -_ . _ ' M1, Ce�hv�af,i��'1u,e�25 Zfe�s��of s'evvice May 15, 2009 Project No. KE080762B Renton School District Capital Projects Office 7812 South 124`� Street Seattle, Washington 98178 Attention: Mr. Stewart L. Shusterman Subject: Subsurface Exploration, Geologic Hazards, and Preliminary Geotechnical Engineering Report Hazen High School Building Addition 1101 Hoquiam Avenue NE Renton, Washington � Dear Mr. Shusterman: We are pleased to present these copies of our preliminary report for the referenced project. This report summarizes the results of our subsurface exploration, geologic hazards, and geotechnical engineering studies, and offers preliminary recommendations for the design and development of the proposed project. Our report is preliminary since project plans were under development at the time this report was written. We should be allowed to review the recommendations presented in this report and modify them, if needed, once final project plans have been formulated. We have enjoyed working with you on this study and are confident that the recommendations presented in this report will aid in the successful completion of your project. If you should have any questions or if we can be of additional help to you, please do not hesitate to call. Sincerely, ASSOCIATED EARTH SCIENCES, INC. Kirkland, Washington a rt D. Merriman, P. . Principal Engineer KDM/tb KE080762B2 Projects12D080762\KE1W P Kirkland � Everett ■ Tacoma 425-827-7701 425-259-0522 253-722-2992 E ! . ' SUBSURFACE EXPL�RATION, GEOLOGIC HAZARDS, AND PRELIMINARY GEOTECHNICAL ENGINEERING REPORT �I � ' ' Ht�1ZEN HIGH SCHOOL , BUILDING ADDITION Renton, Washington Prepared for: Renton School District Capital Projects Office 7812 South 124`� Street Seattle, Washington 98178 Prepared by: Associated Earth Sciences, Inc. 911 5`� Avenue, Suite 100 Kirkland, Washington 98033 425-827-7701 ' Fax: 425-827-5424 ' May 15, 2009 Project No. KE080762B Subsccrface Fxploration, Geologic Hazards, and Hazen High School Building Addition Preliminary Geotechnical Engineering Report Renton, Warhington Project and Site Conditions I. PROJECT AND SITE CONDITIONS � 1.0 INTRODUCTION This report presents the results of our subsurface exploration, geologic hazards, and preliminary geotechnical engineering studies for the proposed building addition to Hazen High School. The site location is shown on Figure 1, "Vicinity Map." The approximate location of exploration borings completed for this study are shown on the "Site and Exploration Plan," Figure 2. Logs of the subsurface explorations completed for this study are included in the Appendix. 1.1 Purpose and Scope The purpose of this study was to provide geotechnical engineering design recommendations to , be utilized in the preliminary design of the project. This study included a review of selected available geologic literature, advancing �ive hollow-stem auger soil borings, and performing geologic studies to assess the type, thickness, distribution, and physical properties of the subsurface sediments and shallow ground water. Geotechnical engineering studies were completed to establish recommendations for the type of suitable foundations and floors, allowable foundation soil bearing pressure, anticipated foundation and floor settlement, pavement recommendations, and drainage considerations. This report summarizes our fieldwork and offers preliminary recommendations based on our present understanding of the project. We recommend that we be allowed to review the recommendations presented in this report and revise them, if needed, when a project design has been finalized. 1.2 Authorization Authorization to proceed with this study was granted by Mr. Stewart L. Shusterman of Renton School District. Our work was completed in general accordance with our scope of work and cost proposal dated April 30, 2009. This report has been prepared for the exclusive use of Renton School District and its agents for specific application to this project. Within the limitations of scope, schedule, and budget, our services have been performed in accordance with generally accepted geotechnical engineering and engineering geology practices in effect in this area at the time our report was prepared. No other warranty, express or implied, is made. 2.0 PROJECT AND SITE DESCRIPTION This report is based on a site layout concept drawing provided by Coughlin Porter Lundeen, the project engineer, which was used as the basis for Figure 2 of this report. The proposed May 15, 2009 ASSOCIATED EARTH SCIENCES, INC. lPUib-KE08076282-Projects1200807621KE1WP Page 1 i Subsurface Exploration, Geologic Hazards, and Hazen High Scliool Buildi�zg Addition Preliminary Geotechnical Engineering Report ' Renton, Wasl:ingto�: Project and Site Conditions project will include a building addition which will extend north and west from entrances along , the rnain school building, past the current locations of two portable classrooms, and connecting to an existing classroom building. The areas currently proposed for the building addition are covered with grass or existing paved surfaces. At the time this report was written, no grading ' plan or detailed structural designs had been completed. For ihe purpose of preparing this report, we have assumed the new structure and associated paving will be constructed close to existing grades, and that the new structure will be a one- to two-story building, with relatively light foundation loads. ' The project site is that of the existing Hazen High School. The existing school includes several buildings with paved parking and driveways surrounding the buildings and grass athletic fields to the west. The site has heen graded to its current configuration by past earthwork on-site. Site topography is relatively flat to gently sloping within the areas proposed for construction, except where adjacent to the existing building to the south of the proposed addition. Along this existing building, the existing grade slopes upward roughly 4 feet from the greater part of the proposed addition footprint to the existing sidewalk. It is likely ttiat this slope was created ; during previous site and infrastructure grading. The existing slopes are not expected to be subject to regulation as critical areas. 3.0 SUBSURFACE EXPLORATION ', � Our subsurface exploration completed for this project included advancing five hollow-stem ' ; auger soil borings. The conclusions and recommendations presented in this report are based � on the explorations completed for ihis study. The locations and depths of the explorations were completed within site and budget constraints. 3.1 Exploration Borings ' The exploration borings were completed by advancing hollow-stem auger tools with a track- mounted drill rig. During the drilling process, samples were obtained at generally 2.5- to 5-foot-depth intervals. The exploration borings were continuously observed and logged by a representative from our firm. The exploration logs presented in the Appendix are based on the field logs, drilling action, and inspection of the samples secured. Disturbed but representative samples were obtained by using the Standard Penetration Test (SPT) procedure in accordance with American Society for Testing ancl Materials , (ASTM):D 1586. This test and sampling method consists of driving a standard, 2-inch ' outside-diameter, split-barrel sampler a distance of 18 inches into the soil with a 140-pound ', hammer free-falling a distance of 30 inches. The number of blows for each 6-inch interval is '� i recorded, and the number of blows required to drive the sampler the final 12 inches is known , May 1 S, 2009 ASSOCIATED EARTH SCIENCES,INC. ' JPL✓rb-KE08076?U2-Projecrs120iD807631KE1WP Page 2 Sc�bsurface Exploration, Geologic Hazards, and Hazen High School Building Addition Preliminary Geotechnical Engineering Report Renton, Washington Project and Site Coriditiorrs as the Standard Penetration Resistance ("N") or blow count. If a total of 50 is recorded within one 6-inch interval, the blow count is recorded as the number of blows for the corresponding number of inches of penetration. The resistance, or N-value, provides a measure of the relative density of granular soils or the relative consistency of cohesive soits; these values are plotted on the attached exploration boring logs. The samples obtained from the split-barrel sampler were classified in the field and representative portions placed in watertight containers. The samples were then transported to our laboratory for further visua] classification. 4.0 SUBSURFACE CONDITIONS Subsurface conditions at the project site were inferred from the field explorations accomplished for this study, visual reconnaissance of the site, and review of selected applicable geologic literature. Because of the nature of exploratory work below ground, interpolation of subsurface conditions between field explorations is necessary. It should be noted that differing subsurface conditions may sometimes be present due to the random nature of deposition and the alteration of topography by past grading and/or filling. The nature and extent of any variations between the field explorations may not become fully evident until construction. 4.1 Stratigraphy Surficial Topsoil Exploration borings EB-3 through EB-5, which were completed in unpaved areas, generally encountered approximately 4 to 12 inches of topsoil and grass. Topsoil is not suitable for structural support, and should be stripped from structural areas. Excavated topsoil may be suitable for reuse in landscape areas. Fill Existing fill was encountered in exploration borings EB-1, EB-2, EB-4, and EB-5 to a depth of up to approximately 7'/z feet below the existing ground surface. The encountered fill exhibited a wide range of soil densities, and appeared to consist of materials derived on-site and moved or disturbed during earlier site work. The fill generally was free of organics or roots; although trace amounts of organics were observed in EB-1. Due to the variability in density, the exisiing fill will require removal from building areas and remedial preparation below pIanned paving. May I5, 2009 ASSOCIATED EARTH SCIENCES, INC. JPLIrb-KE080762B2-Projec�.s1200807621KE1WP Page 3 Suhsurface Exploration, Geologic Hazards, and Hazen High School Building Addition Prelinunary Geotechnical Engineering Report � Renton, Washington Project and Site Conditions E Vashon Ice Contact Sediments/Recessional Outwash ; Below the existing fill or topsoil, our exploration borings encountered variable silty sand with gravel, interbedded in places with fine sand zones or silt seams. Density typically varied from medium dense to dense, increasing to very dense within zones containing increased amounts of gravel. These native sediments are interpreted to represent Vashan ice contact sediments. Ice contact sediments were initially deposited above or within a glacial ice mass, and were subsequently redeposited when the ice melted. Ice contact sediments can be stratified and alluvially re-worked, and stratification was noted in our exploration borings on this site. This re-working, in places, resulted in sediments resembling recessional outwash, which was deposited by meltwater streams flowing from the receding Vashon glacier approximately 10,000 years ago. Ice contact or recessional outwash deposits are typically not consolidated to the same degree as advance outwash and lodgement till sediments, though some degree of compaction by glacial activity can occur. The ice contact sediments observed in our exploration borings for this project are silty and are considered highly moisture-sensitive. With proper preparation, these sediments will provide adequate support for the new building addition or paved surfacing. Excavated ice contact or wet recessional outwash sediments are expected to be above optimum moisture content for compaction purposes, and will need to be dried during favorable dry site and weather conditions to allow their reuse in structural fill applications. At the locations of exploration borings EB-1 and EB-4, the ice contact/recessional outwash deposits extended beyond the maximum depth explored of approximately 21.5 feet. Vashon Lodgement Till Sediments encountered below the ice contact sediments at the location of exploration boring EB-5 consisted of very dense, silty sand with gravel. We interpret these sediments to be representative of Vashon lodgement till. The Vashon lodgement till was deposited directly from basal, debris-laden glacial ice during the Vashon Stade of the Fraser Glaciation approximately 12,500 to 15,000 years ago. The high relative density of the unweathered till is due to its consolidation by the massive weight of the glacial ice from which it was deposited. At the location of EB-5, the till extended beyond the maximum depth explored of approximately 21.5 feet. Pre-Fraser Fine-grained Deposit This unit was observed in exploration borings EB-2 and EB-3. This unit underlies the Vashon- age deposits described above and extended beyond the maximum depths explored of approximately 21.5 to 20.5 feet at EB-2 and EB-3, respectively. The pre-Fraser fine-grained deposits generally consist of hard, moist, bluish gray, silt, with gravel inderbeds of dense to very dense sand or silty sand. This unit typically possesses high strength and low May IS, 2009 ASSOCIATED EARTH SCIENCES, INC. !PL/tb-KE08076?BZ-Projecrs12q7807621KE1WP Page 4 Subsurface Exploration, Geologic Hazards, and Hazen High School Btulding Addition Preliminary Geotechnical Et:gineering Report , Renton, Washington Project and Site Condiri�,-� compressibility attributes that are favorable for support of foundations, floor slabs, and pa� with proper preparation. The high relative density characteristic of the pre-Fraser fine-grained deposits is due to its consolidation by one or more advances of glacial ice after deposition. 4.2 Geologic Mapping We reviewed a published geologic map of the area (Geologic Map of King County, Washington, by Derek B. Booth, Kathy A. Troost, and Aaron P. Wisher, 2006). The referenced map indicates that the site vicinity is characterized primarily by lodgement till at the ground surface, with smaller areas of advance outwash neazby. The shallow native sediments observed in our explorations for this project are not consistent with this mapping, although lodgement till was encountered at depth. It is not unusual to find localized areas that vary from published regional scale geologic mapping, and that is the case with this site. Ice contact sediments occur regularly in the project area above lodgement till. We recommend that design activities for this project be based on subsurface materials observed in our on-site explorations. 4.3 Hydrology Three of the exploration borings encountered ground water seepage, typically originating from granular horizons within the ice contact/recessional outwash sediments. The encountered ground water seepage also appeared to be perched above lower permeability Vashon lodgement till or pre-Fraser fine-grained deposits at depth. We expect ground water seepage across much of the site to be limited to interflow. Interflow occurs when suiface water percolates down through the surficial weathered or higher permeability sediments and becomes perched atop underlying, lower permeability sediments. It should be noted that the occurrence and level of ground water seepage at the site may vary in response to such factors as changes in season, precipitation, and site use. May IS, 20119 ASSOCIATED EARTH SCIENCES, INC. lPUtb-KE(�0762B2-ProjectslZ0�D8076?IKEIWP Page 5 1 i Subsurface Exploration, Geologic Hazards, and Hazen High School Bicilding Addition Prelirninary Geotech�iical Engineering Report ! Re►uon, Washington Geologic Hazards and Mitigations II. GEOLOGIC HAZARDS AND MITIGATIONS The following discussion of potential geologic hazards is based on the geologic, slope, and ' ground and surface water conditions, as observed and discussed herein. The discussion will be limited to seismic and erosion issues. 5.0 SEISMIC HAZARDS AND MITIGATIONS Earthquakes occur regularly in the Puget Lowland. The majority of these events are small and � are usually not felt by people. However, large earthquakes do occur, as evidenced by the 1949, 7.2-magnitude event; the 2001, 6.8-magnitude event; and the 1965, 6.5-magnitude event. The 1949 earthquake appears to have been the largest in this region during recorded � history and was centered in the Olympia area. Evaluation of earthquake return rates indicates that an earthquake of the magnitude between 5.5 and 6.0 is likely within a given 20- year period. Generally, there are four types of potential geologic hazards associated with large seismic events: 1) surficial ground rupture, 2) seismically induced landslides, 3) liquefaction, and 4) ground motion. The potential for each of these hazards to adversely impact the proposed project is discussed below. 5.1 Surficial Ground Rupture The subject site is located approximately 2 miles to the south of the Seattle Fault Zone. Recent studies by the United States Geological Survey (USGS) (e.g., Johnson, et al., 1994, Origin and Evolution of the Seattle Fault and Seattle Basin, Washington, Geology, v. 22, p.71-74; and Johnson et al., 1999, Active Tectonics of the Seattle Fault and Central Puget Sound Washington - Implications for Earthquake HaZards, Geological Society of America Bulletin, July 1999, v. 111, n. 7, p. 1042-1053) have provided evidence of surficial ground rupture along a northern splay of the Seattle Fault. The recognition of this fault is relatively new, and data pertaining to it are limited, with the studies still ongoing. According to the USGS studies, the latest movement of this fault was about 1,100 years ago when about 20 feet of surficial displacement took place. This displacement can presently be seen in the form of raised, wave- cut beach terraces along Alki Point in West Seattle and Restoration Point at the south end of Bainbridge Island. The recurrence interval of movement along this fault system is still unknown, although it is hypothesized to be in excess of several thousand years. Due to the suspected long recurrence interval, the potential for surficial ground rupture is considered to be low during the expected life of the structures, and no mitigation efforts beyond complying with the current (2006) International Building Code (IBC) are recommended. � May I5, 2009 ASSOCIATED EARTH SCIENCES, INC. JPUrb-KE080763B2-Projeas1300807621KEIWP Page 6 Subsurface Exploration, Geologic Hazards, and Hazen High School Building Addition Pre[iminary Geotechnical Engineering Report Renton, Washington Geologic Hazards and Mitigations 5.2 Seismically Induced Landslides It is our opinion that the potential risk of damage to the proposed development by seismically induced slope failures is low due to the lack of steep slopes in the project area. 5.3 Liquefaction Liquefaction is a process through which unconsolidated soil loses strength as a result of vibrations, such as those which occur during a seismic event. During normal conditions, the ' weight of the soil is supported by both grain-to-grain contacts and by the fluid pressure within the pore spaces of the soil below the water table. Extreme vibratory shaking can disrupt the grain-to-grain contact, increase the pore pressure, and result in a temporary decrease in soil shear strength. The soil is said to be liquefied when nearly all of the weight of the soil is supported by pore pressure alone. Liquefaction can result in deformation of the sediment and settlement of overlying structures. Areas most susceptible to liquefaction include those areas underlain by non-cohesive silt and sand with low relative densities, accompanied by a shallow water table. The subsurface conditions encountered at the site pose little risk of liquefaction due to relatively high density and lack of shallow ground water. No detailed liquefaction analysis was completed as part of this study, and none is warranted, in our opinion. 5.4 Ground Motion It is our opinion that any earthquake damage to the proposed structure, when founded on a suitable bearing stratum in accordance with the recommendations contained herein, will be caused by the intensity and acceleration associated with the event and not any of the above- discussed impacts. Structural design of the proposed building should follow the 2006 IBC. Information presented by the USGS Earthquake Hazards Program indicates a spectral acceleration for the project area for short periods (0.2 seconds) of Ss = 1.401 and for a 1- second period of S� = 0.477. Based on the results of subsurface exploration and on an estimation of soil properties at depth utilizing available geologic data, Site Class "C", in conformance with Table 1613.5.2 of the IBC, may be used. 6.0 EROSION HAZARDS AND MITIGATIONS As of October 1, 2008, the Washington State Department of Ecology (Ecology) Construction Storm Water General Permit (also known as the National Pollutant Discharge Elimination System [NPDES] permit) requires weekly Temporary Erosion and Sedimentation Control (TESC) inspections and turbidity monitoring of site runoff for all sites 1 or more acres in size May 1 S, 2009 ASSOCIATED EARTH SCIENCES, INC. JPiJtb-KFA80763B2-Projec1s1200807621KE1WP Page 7 � ( Subsurface Exploration, Geologic Hazards, and ' Hazen High School Btulding Addition Preliminary Geotechnical Engineering Report � Renton, Washington Preliminary Design Recommendations III. PRELIMINARY DESIGN RECOMMENDATIONS f � '�.0 INTRODUCTION The proposed building addition area is underlain by a layer of surficial existing fill that is variable in density. Existing fill is not suitable for support of new foundations, and warrants ' remedial preparation where it occurs below paving and similar lightly loaded structures. Structural fill or native ice contact/recessional outwash deposits are suitable for support of � shallow foundations with proper preparation. 8.0 SITE PREPAR.ATION i Existing buried utilities, vegetation, topsoil, and any other deleterious materials should be removed where they are located below planned construction areas. All disturbed soils resulting ; from demolition activities should be removed to expose underlying, undisturbed, native sediments and replaced with structural fill, as needed. All excavations below final grade made for demolition activities should be backfilled, as needed, with structural fill. Erosion and . surface water control should be established around the clearing limits to satisfy local requirements. ' Once demolition has been completed, existing �11 should be addressed. The observed fill depth in our borings was up to approximately 7'/z feet below existing grade. We recommend that existing fill be removed from below areas of planned foundations to expose underlying undisturbed native sediments, followed by restoration of the planned foundation grade with structural fill. Removal of existing fill should extend laterally beyond the building footprint by a distance equal to the depth of overexcavation. For example, if existing fill is removed to a � depth of 2 feet below a planned footing area, the excavation should also extend laterally 2 feet beyond the building footprint in that area. Care should be taken not to disturb support soils of existing foundations. Support soils should be considered those soils within a prism projected downward and outward from existing footings at inclinations of 1H:1V. Where existing fill is removed and replaced with structural fill, conventional shallow foundations may be used for building support. The required depth of removal should be determined in the field based on actual conditions encountered during excavation. 8.1 Site Drainage and Surface Water Control The site should be graded to prevent water from ponding in construction areas and/or flowing into excavations. Exposed grades should be crowned, sloped, and smooth drum-rolled at the end of each day to facilitate drainage. Accumulated water must be removed from subgrades , ; May 1 S, 2009 ASSOCIATED EARTH SCIENCES, INC. IIs JPUtb-KE08076?B2-Projecta1300807611KL•IWP Page 12 I � Subsurface Exploration, Geologic Hazards, and Hazen High School Building Addition Preliminary Geotechnical Engineering Repon Renton, Washington Preliminary Design Recommendatio�u and work areas immediately prior to performing further work in the area. Equipment access may be limited, and the amount of soil rendered unfit for use as structural fill may be greatly increased, if drainage efforts are not accomplished in a timely sequence. If an effective drainage system is not utilized, project delays and increased costs could be incurred due to the greater quantities of wet and unsuitable fill, or poor access and unstable conditions. Our exploration borings encountered evidence of seasonal ground water seepage from granular intervals within the ice contact/recessional outwash deposits. We also anticipate that perched ground water could be encountered in excavations completed during construction. We do not anticipate the need for extensive dewatering in advance of excavations. The contractor should be prepared to intercept any ground water seepage entering the excavations and route it to a suitable discharge location. Final exterior grades should promote free and positive drainage away from the buildings at all times. Water must not be allowed to pond or to collect adjacent to foundations or within the immediate building azea. We recommend that a gradient of at least 3 percent for a minimum distance of 10 feet from the building perimeters be provided, except in paved locations. In paved locations, a minimum gradient of 1 percent should be provided, unless provisions are included for collection and disposal of surface water adjacent to the structures. 8.2 Sub�rade Protection To the extent that it is possible, existing pavement should be used for construction staging areas. If building construction will proceed during the winter, we recommend the use of a working surface of sand and gravel, crushed rock, or quarry spalls to protect exposed soils, particularly in areas supporting concentrated equipment traffic. In winter construction staging areas and areas that will be subjected to repeated heavy loads, such as those that occur during construction of masonry walls, a minimum thickness of 12 inches of quarry spalls or 18 inches of pit run sand and gravel is recommended. If subgrade conditions are soft and silty, a geotextile separation fabric, such as Mirafi SOOx or approved equivalent, should be used between the subgrade and the new fill. For building pads where floor slabs and foundation construction will be completed in the winter, a similar working surface should be used, composed of at least 6 inches of pit run sand and gravel or crushed rock. Construction of working surfaces from advan�cing fill pads could be used to avoid directly exposing the subgrade soils to vehicular traffic. Foundation subgrades may require protection from foot and equipment traffic and ponding of runoff during wet weather conditions. Typically, compacted crushed rock or a lean-mix concrete mat placed over a properly prepared subgrade provides adequate subgrade protection. Foundation concrete should be placed and excavations backfilled as soon as possible to protect the bearing surface. May I5, 2009 ASSOCIATED EARTH SCIENCES, INC. lPLJrb-KE080762B2-ProjecrsL00807621KElWP Page 13 ! � Subsurface Ezploration, Geologic Hazards, and � Haze�t High Schoo[Building Addition Preliminary Georechnical Engineering Report � Renton, Washington Preliminary Design Recommendalions � 8.3 Proof-Rolling and Subgrade Compaction � Following the recommended demolition, site stripping, and planned excavation, the stripped subgrade within the building areas should be proof-rolled with heavy, rubber-tired construction j equipment, such as a fully loaded, tandem-axle dump truck. Proof-rolling should be performed prior to structural fill placement or foundation excavation. The proof-roll should be monitored by the geotechnical engineer so that any soft or yielding subgrade soils can be identified. Any soft/loose, yielding soils should be removed to a stable subgrade. The subgrade should then be scarified, adjusted in moisture content, and recompacted to the required density. Proof-rolling should only be attempted if soil moisture contents are at or near optimum moisture content. Proof-rolling of wet subgrades could result in further degradation. Low areas and excavations may then be raised to the planned finished grade with compacted structural fill. Subgrade preparation and selection, placement, and compaction of structural fill should be pexformed under engineering-controlled conditions in accordance with i j the project specifications. � 8.4 Overexcavation/Stabilization Construction during extended wet weather periods could create the need to overexcavate j exposed soils if they become disturbed and cannot be recompacted due to elevated moisture content and/or weather conditions. Even during dry weather periods, softlwet soils, which ; may need to be overexcavated, may be encountered in some portions of the site. If ' overexcavation is necessary, it should be confirmed through continuous observation and testing � by AESI. Soils that have become unstable may require remedial measures in the form of one or more of the following: � 1. Drying and recompaction. Selective drying may be accomplished by scarifying or windrowing surficial material during extended periods of dry and warm weather. 2. Removal of affected soils to expose a suitable bearing subgrade and replacement with compacted structural fill. 3. Mechanical stabilization with a coarse-crushed aggregate compacted into the subgrade, possibly in conjunction with a geotextile. � 4. Soil/cement admixture stabilization. 8.5 Wet Weather Conditions , If construction proceeds during an extended wet weather construction period and the moisture- sensitive site soils become wet, they will become unstable. Therefore, the hids for site grading operations should be based upon the time of year that construction will proceed. It is expected May IS, 2009 ASSOCIATED EARTH SCIENCES, INC. JPUtb-KE080762B2-Projectsl_�(.108076?IKEIWP Page 14 Subsurface Exploration, Geologic Hazards, and ' Nazen High School Building Addition Preliminary Geotechnica!Engineering Report �� Renton, Washingto�: Preliminary Design Recommendations that in wet condirions additional soils may need to be removed and/or other stabilization methods used, such as a coarse crushed-rack working mat to develop a stable condition if silty subgrade soils are disturbed in the presence of excess moisture. The severity of construction disturbance will be dependent, in part, on the precautions that are taken by the contractor to protect the moisture- and disturbance-sensitive site soils. If overexcavation is necessary, it should be confirmed through continuous observation and testing by a representative of our firm. 8.6 Temporary and Permanent Cut Slopes In our opinion, stable construction slopes should be the responsibility of the coutractor and should be determined during construction. For estimating purposes, however, we anticipate that temporary, unsupported cut slopes in the existing fill can be made at a maximum slope of 1.SH:1V or flatter. Temporary slopes in ice contact/recessional outwash deposits may be planned at 1H:1V. As is typical with earthwork operations, some sloughing and raveling may occur, and cut slopes may have to be adjusted in the field. If ground water seepage is encountered in cut slopes, or if surface water is not routed away from temporary cut slope faces, flatter slopes will be required. In addition, WISHA/OSHA regulations should be followed at all tunes. Permanent cut and structural fill slopes that are not intended to be exposed to surface water should be designed at inclinations of 2H:1V or flatter. All permanent cut or fill slopes should be compacted to at least 95 percent of the modified Proctor maximum dry density, as determined by ASTM:D 1557, and the slopes should be pratected from erosion by sheet plastic until vegetation cover can be established during favorable weather. 8.7 Frozen Subgrades If earthwork takes place during freezing conditions, all exposed subgrades should be allowed to thaw and then be recompacted prior to placing subsequent lifts of structural fill or foundation components. Altematively, the frozen material could be stripped from the subgrade to reveal unfrozen soil prior to placing subsequent lifts of fill or foundation components. The frozen soil should not be reused as structural fill until allowed to thaw and adjusted to the proper moisture content, which may not be possible during winter months. 9.0 STRUCTUR.AL FILL All references to structural fill in this report refer to subgrade preparation, fill type and placement, and compaction of materials, as discussed in this section. If a percentage of compaction is specified under another section of this report, the value given in that section should be used. May 1 S, 2009 ASSOCIATED EARTH SCIENCES, INC. 1PLltb-KEA8076ZB2-Projecu120D807631KEIWP Page 15 � Subsicrface Exploration, Geologic Hazards, and � Hazen High School Building Addition Prelirninary Geotechnical Engineering Report � Renton, Washington Preliminary Design Recommendations i 1- After stripping, planned excavation, and any required overexcavation have been performed to the satisfaction of the geotechnical engineer, the upper 12 inches of exposed ground in areas to receive fill should be recompacted to 90 percent of the modified Proctor maximum density using ASTM:D 1557 as the standard. If the subgrade contains silty soils and too much moisture, adequate recompaction may be difficult or impossible to obtain and should probably not be attempted. In lieu of recompaction, the area to receive fill should be blanketed with washed rock or quarry spalls to act as a capillary break between the new fill and the wet subgrade. Where the exposed ground remains soft and further overexcavation is impractical, placement of an engineering stabilization fabric may be necessary to prevent contamination of , the free-draining layer by silt migration from below. � After recompaction of the exposed ground is tested and approved, or a free-draining rock � course is laid, structural fill may be placed to attain desired grades. Structural fill is defined as non-organic soil, acceptable to the geotechnical engineer, placed in maximum 8-inch loose j lifts, with each lift being compacted to 95 percent of the modified Proctor maximum density using ASTM:D 1557 as the standard. In the case of roadway and utility trench filling, the � backfill should be placed and compacted in accordance with current City of Renton codes and standards. The top of the compacted fill should extend horizontally outward a minimum distance of 3 feet beyond the locations of the roadway edges before sloping down at an angle of 2H:1V. The contractor should note that any proposed fill soils must be evaluated by AESI prior to their use in fills. This would require that we have a sample of the material 72 hours in advance to perform a Proctor test and determine its field compaction standard. Soils in which the amount of fine-grained material (smaller than the No. 200 sieve) is greater than approximately 5 percent (measured on the minus No. 4 sieve size) should be considered moisture-sensitive. Use of moisture-sensitive soil in structural fills should be lunited to favorable dry weather conditions. The native and existing fill soils present on-site contained variable amounts of silt and are considered moisture-sensitive. In addition, construction equipment traversing the site when the soils are wet can cause considerable disturbance. If fill is placed during wet weather or if proper compaction cannot be obtained, a select import material consisting of a clean, free- draining gravel and/or sand should be used. Free-draining fill consists of non-organic soil with the amount of fine-grained material limited to 5 percent by weight when measured on the minus No. 4 sieve fraction with at least 25 percent retained on the No. 4 sieve. A representative from our firm should inspect the stripped subgrade and be present during placement of structural fill to observe the work and perform a representative number of in-place density tests. In this way, the adequacy of the earthwork may be evaluated as filling progresses, and any problem areas may be corrected at that time. It is important to understand ' that taking random compaction tests on a part-time basis wili not assure uniformity or May 1 S, 2009 ASSOCIATED EARTH SCIENCES, INC. JPL✓7b-KE08076?Ii3-Projects1200807621KE1WP Page 16 Subsurface Fxploration, Geologic Hazards, and Hazen High School Building Addition Prelinzinary Geotechnical Engineeri�Tg Report Rentori, Washington Preiiminary Design Recommertdations acceptable performance of a fill. As such, we are available to aid the school district in � developing a suitable monitoring and testing program. 10.0 FOUNDATIONS Spread footings rnay be used for building support when founded directly on undisturbed ice ' contact/recessional outwash deposits or on structural fill placed above suitable native deposits, as previously discussed. We recommend that an allowable bearing pressure of 3,000 pounds per square foot (ps�} be used for design purposes, including both dead and live loads. An increase of one-third may be used for short-term wind or seismic loading. Higher foundation soil bearing pressures are possible for foundations supported entirely on undisturbed ice contact/recessional outwash deposits; however, we do not expect that higher bearing pressures will be needed. If higher foundation soil bearing pressures are needed, we should be allowed to offer situation-specific recommendations. Perimeter footings should be buried at least 18 inches into the sunounding soil for frost protection. However, all footings must penetrate to the prescribed bearing stratum, and no footing should be founded in or above organic or loose soils. All footings should have a minimum width of 18 inches. It should be noted that the area bound by lines extending downward at 1H:1V from any footing must not intersect another footing or intersect a filled area that has not been compacted to at Ieast 95 percent of ASTM:D 1557. In addition, a 1.SH:1V line extending down from any footing must not daylight because sloughing or raveling may eventually undermine the footing. Thus, footings should not be placed near the edge of steps or cuts in the bearing soils. Anticipated settlement of footings founded as described above should be on the order of �a inch or less. However, disturbed sail not removed from footing excavations prior to footing placement could result in increased settlements. All footing areas should be inspected by AESI prior to placing concrete to verify that the design bearing capacity of the soils has been attained and that construction conforms to the recommendations contained in this report. Such inspections may be required by the governing municipality. Perimeter footing drains should be provided, as discussed under the "Drainage Considerations" section of this report. Care should be exercised when constructing new foundations adjacent to existing building foundations. If possible, the new foundations should be founded at the same elevation as the existing. If new footings are founded above existing footings, they will impart new loads that may lead to settlement of the existing footings. If adjacent foundations are to be founded at different elevations, the structural engineer should review the effect of the new loads on May I5, 2009 ASSOCIATED EARTH SCIENCES, INC. lPUtb-KE080762B3-Projecrsl?00807621KEIWP Page 17 4 � Subsurface Exploration, Geologic Hazards, and Hazen High School Building Addition Preliminary Geotec/inical Engineering Report Re�uon, Washington Preliminary Design Reconvnendations foundations and stem walls. If new foundations will be placed below existing footing � elevations, the existing elements may need to be underpinned. If any part of the excavations will intersect a 45-degree line extended down from the base of the existing building foundation, then that portion of the excavation should be completed and backfilled in short segments on the order of 5 to 10 feet in length. Care should be taken so as not to undermine the existing foundation elements. Consideration should be given to deferring the installation of a settlement-sensitive finish, as �; long as practical, especially at the transition from the new to existing building. To further reduce the potential for differential movement, a closure pour strip between the new and existing floors could be deferred until the new dead loads are in place. 10.1 Drainage Considerations Foundations should be provided with foundation drains placed at the base of footing elevation. , Drains should cansist of rigid, perforated, polyvinyl chloride (PVC) pipe surrounded by washed pea gravel. The drains should be constructed with sufficient gradient to allow gravity discharge away from the proposed buildings. Roof and surface runoff should not discharge ; into the footing drain system, but should be handled by a separate, rigid, tightline drain. In ' � planning, exterior grades adjacent to walls should be sloped downward away from the �, proposed structures to achieve surface drainage. � ' ; 11.0 FLOOR SUPPORT i Floor slabs can be supported on suitable native sediments, or on structural fill placed above � suitable native sediments. Floor slabs should be cast atop a minimum of 4 inches of clean, washed, crushed rock or pea gravel to act as a capillary break. Areas of subgrade that are ; disturbed (loosened) during construction should be compacted to a non-yielding condition prior to placement of capillary break material. Floor slabs should also be protected from dampness � � by an impervious moisture barrier at least 10 mils thick. The moisture barrier should be placed between the capillary break material and the concrete slab. � 12.0 FOUNDATION WALLS ' All backfill behind foundation walls or around foundation units should be placed as per our recommendations for structural fill and as described in this section of the report. Horizontally ' backfilled walls, which are free to yield laterally at least 0.1 percent of their height, may be � designed using an equivalent fluid equal to 35 pounds per cubic foot (pc fl. Fully restrained, May I5, 2009 ASSOCIATED EARTH SCIENCES, INC. 1PL1rb-KE080762D3-Projeus12008076?IKEIWP Page 18 Subsurface Fxploration, Geologic Hazards, and Hazen High School Building Addition Preliminary Geotechnical Engineering Repon Renton, Washington Preli�ninary Design Recomrnendations horizontally backfilled, rigid walls that cannot yield should be designed for an equivalent fluid of 50 pcf. Walls with sloping backfill up to a maximum gradient of 2H:1V should be designed using an equivalent fluid of 55 pcf for yielding conditions or 75 pcf for fully restrained conditions. If parking areas are adjacent to walls, a surcharge equivalent to 2 feet of soil should be added to the wall height in determining lateral design forces. As required by the 2006 IBC, retaining wall design should include a seismic surcharge pressure in addition to the equivalent fluid pressures presented above. Considering the site soils and the recommended wall backfill materials, we recommend a seismic surcharge pressure of SH and lOH psf, where H is the wall height in feet for the "active" and "at-rest" loading conditions, respectively. The seismic surcharge should be modeled as a rectangular distribution with the resultant applied at the mid-point of the walls. The lateral pressures presented above are based on the conditions of a uniform backfill consisting of excavated on-site soils, or unported structural fill compacted to 90 percent of ASTM:D 1557. A higher degree of compaction is not recommended, as this will increase the pressure acting on the walls. A lower compaction may result in settlement of the slab-on-grade or other structures supported above the walls. Thus, the compaction level is critical and must be tested by our firm during placement. Surcharges from adjacent footings or heavy construcrion equipment must be added to the above values. Perimeter footing drains should be provided for all retaining walls, as discussed under the "Drainage Considerations" section of this report. It is imperative that proper drainage be provided so that hydrostatic pressures do not develop against the walls. This would involve installation of a minimum, 1-foot-wide blanket drain to within 1 foot of finish grade for the full wall height using imported, washed gravel against the walls. A prefabricated drainage mat is not a suitable substitute for the gravel blanket drain unless all backfill against the wall is free-draining. 12.1 Passive Resistance and Friction Factors Lateral loads can be resisted by friction between the foundation and the natural glacial soils or supporting structural fill soils, and by passive earth pressure acting on the buried portions of the foundations. The foundations must be backfilled with structural fill and compacted to at least 95 percent of the maximum dry density to achieve the passive resistance provided below. We recommend the following allowable design parameters: • Passive equivalent fluid = 250 pcf • Coefficient of friction = 0.30 May I.S, 2009 ASSOCIATED EARTH SCIENCES, INC. JPLJ�b-KE080762B2-Projecrsl?00807631KEIWP Page 19 f i , Subsurface Fxploration, Geologic Hazards, mid Hazen High School Building Addition Preliminary Geotechnical Engineering Report ! Renton, Washington Preliminary Design Recomme�tdations 13.0 PAVEMENT RECOMMENDATIONS '': Pavement areas should be prepared in accordance with the "Site Preparation" section of this report. If the stripped native soil or existing fill pavement subgrade can be compacted to ; 95 percent of ASTM:D 1557 and is firm and unyielding, no additional overexcavation is � required. Soft or yielding areas should be overexcavated to provide a suitable subgrade and ; backfilled with structural fill. The pavement sections included in this report section are for driveway and parking areas on- site, and are not applicable to right-of-way improvements. At this time we are not aware of any planned right-of-way improvements; however, if any new paving of public streets is required, we should be allowed to offer situation-specific recommendations. t The exposed ground should be recompacted to 95 percent of ASTM:D 1557. If required, structural fill may then be placed to achieve desired subbase grades. Upon completion of the recompaction and structural fill, a pavement section consisting of 2'h inches of asphaltic concrete pavement (ACP) underlain by 4 inches of 1'/a-inch crushed surfacing base course is the recommended minimum in areas of planned passenger car driving and parking. In heavy traffic areas such as bus lanes, a minimum pavement section consisting of 3 inches of ACP ; underlain by 2 inches of 5/s-inch crushed surfacing top course and 4 inches of 11/a-inch crushed � surfacing base course is recommended. The crushed rock courses must be compacted to 95 a percent of the maximum density, as determined by ASTM:D 1557. All paving materials � should meet gradation criteria contained in the current Washington State Department of Transportation (WSDOT) Standard Specifications. Depending on construction staging and desired performance, the crushed base course material may be substituted with asphalt treated base (ATB) beneath the final asphalt surfacing. The substitution of ATB should be as follows: 4 inches of crushed rock can be substituted with 3 inches of ATB, and 6 inches of crushed rock may be substituted with 4 inches of ATB. ATB should be placed over a native or structural fill subgrade compacted to a minimum of 95 percent relative density, and a 1'h- to 2-inch thickness of crushed rock to act as a working surface. If ATB is used for construction access and staging areas, some rutting and disturbance of the ATB surface should be expected. The general contractor should remove affected areas and replace them with properly compacted ATB prior to final surfacing. 14.0 PROJECT DESIGN AND CONSTRUCTION MONITORING Our report is preliminary since project plans were not finalized at the time this report was ; written. We recommend that AESI perform a geotechnical review of the plans prior to �nal � � May 15, 2009 ASSOCIATED EARTN SCIENCES, INC. - lPLJfb-KE08076?B2-Projecrsl?008076?IKEIWP Page 20 Subsurface Fxploration, Geologic Hazards, and Hazen High School Building Addition Prelirninary Geotechnical Engineering Report . Renton, Washington Prelirninary Design Reco►ranendations design completion. In this way, we can confirm that our earthwork and foundation recommendations have been properly interpreted and implemented in the design. We are also available to provide geotechnical engineering and monitoring services during construction. The integrity of the foundation system depends on proper site preparation and construction procedures. In addition, engineering decisions may have to be made in the field in the event that variations in subsurface conditions become apparent. Construction monitoring services are not part of this current scope of work. If these services are desired, please let us know, and we will prepare a cost proposal. We have enjoyed working with you on this study and are confident that these recommendations will aid in the successful completion of your project. If you should have any questions or require further assistance, please do not hesitate to call. Sincerely, ASSOCIATED EARTH SCIENCES, INC. Kirkland, Washington ¢��,M���i,y J o Was ti F yi -4,y � �� �•� C� �- �_ 2 _ Q ,�, 9 iss�o o �� (�` `�GISTER� �� SS�QNA��? Jeffrey P. Laub, P.G., P.E.G. Kurt D. Merriman, P.E. Project Engineering Geologist Principal Engineer Attachments: Figure 1: Vicinity Map Figure 2: Site and Exploration Plan Appendix: Exploration Logs May I5, 2009 ASSOCIATED EARTH SCIENCES, INC. JPLJtb-KEOB076?B3-Projects1200807621KE1WP Page 21 � .J � . _. . . . . . . -... �.m ..:�. . . . . . . �. 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" . . .. j ,�;s� �_EB-4 _ u " �' �� - - --- - ., . . .� _,- - - - . . . - ; � -- . , . - ; , �. . ; �. . -- ; < e �EB-5 - � : � ,.; �- , - � � . �Eg-1 _ � _._ '= � :� : , --- � - _�_-—_— .�._�—'T . ----—;�.-1 , __ ` � ,. . $ '' � APPROXIMATE W LOCATION OF N � PROPOSED � � ADDITION � ° o ao so 0 m 0 $ REFERENCE: D.R.STRONG CONSULTING ENGINEERS FEET 5 � r � m Associated Earth Sciences,Inc. SITE AND EXPLORATION PLAN FiGURE 2 N = s�,_ HAZEN HIGH SCHOOL DATE 5/09 � �=' ' � ���� r � RENTON,WASHINGTON PROJ.NO. KE0807626 0 � H A � W � a � Assoc�ated Eartb Sciences,lnc. EX loration Lo �y.. Project Number Exploration Number Sheet 0 � � � KE080762B EB-1 1 of 1 Project Name Hazen High School Addition Ground Surface Elevation(ft) �471' , �ocation Renton WA oatum _Nav�RR DrilledEquipment Davies Drilling Date Start/Finish �/R1fl9,.r,/R/fl9 1 Hammer WeighUDrop 140#/30" Hole Diameter(in) 6" c w _ �� � °' L � � � � BIOWSIFOOt N � a �E �Q� 3 D T � �'`� �� �° m `L� DESCRIPTION " � to 20 3o ao �o 2 1/Y asphalL a S-� ,Crushed rock(angular)5/8". __� t3 �2 I � Fill 13 Mast,rust-stained brownish gray,silty fine to medium SAND. Mast,rust-stained brownish gray,silty fine to medium SAND,with gravel. s S-2 5 10 ( 5 I 5 Mast,same,trace organics in sampler tip. s S-3 g �g - - - - - -- ---- ----- - - - - �� I I Vashon Recessional Outwash Mast,rust-stained brownish gray,fine to medfum SAND,with silt and Uace z S� gravel. 2 �a 2 I I �� Mofst,rust-stalned brownish gray,silty fine to medium SAND,with gravel 6 S-5 and sandier zones. s �t to I I Moist,brownish gray,silty fine to medium SAND,with gravel(decomposed 72 S-6 g�nite}. i5 �3a 19 ( I �5 �� Mast to wet,same,with sandier zones. - 8 12 14 t I Zd Wet,same,with fine sand zones. I I S-8 � s 2� — — --- --- 72 Bottom of exploration boring at 21 5 feet I I No free water 25 I I I 30 I I 35 �0 r M T W � a (9 N Sampler Type(ST): � o m 2"OD Split Spoon Sampler(SPT) � No Recovery M-Moisture Logged by: JPL o � 3"OD Split Spoon Sampler(D 8 M) � Ring Sample SZ Water Level() ' Approved by: W � Grab Sample Q Shelby Tube Sample t Water Level at time of drilling(ATD) ' Associated Earth Sciences,Inc. EX loration Lo _:� � � � � Project Number Exploration Number Sheet _,� -�e," r�iti� KE080762B EB-2 1 of 1 Project Name Hazen Hiqh School Addition Ground Surface Elevation(ft) �466' ' Location Renton. WA Datum NAVI�RR ` DrilledEquipment Davies Drilling Date Start/Finish 51R/(lA .�i/R/�9 Hammer WeighUDrop 140#/30" Hole Diameter(in) �^ � � L n m� � � BIOWS/FOOt • �' � n S E `� � n `y 3 o T c�n �� �o �6m L DESCRIPTION " � �0 2o so ao � ,2 1/2"aspha�t. to S-1 �Gravel base(1'to 1 1/2"rock). � t� �23 Fill �2 Moist,brownish gray,silry fine to medium SAND,with gravel. Moist,slightly rust-stained brownish gray,silry fine to medium SAND,with �s S-2 gravel. 24 51 - 27 � Mast,brownish gray,silty fine to medium SAND,with gravel and sandier 6 S-3 zones. �s s 22 Vashon Recessional Outwash ------ - -- �� Moist to wet,rust-stained brownish gray,silty fine to medium SAND. g S'4 12 �2 14 15 Wet, rust-stained brownish gray,fine to medium SAND,with silt interbeds. 8 5'S � 14 8 14 - - -- -- - - ----- -- Pre-Olympia Fine-Grained Deposits Driller reports silty drilling action at 17'. 20 Moist,bluish gray,SILT,with sandy interbeds. 15 __ S� i 8 �a -- -- -- 27 Bottom of exploration boring al 21 5 feel Water at 16'(perched) 25 30 35 0 N � >. N � 'a � � Sampler Type(ST): o m 2"OD Split Spoon Sampler{SPT) � No Recovery M-Moisture Logged by: JPL o m 3"OD Split Spoon Sampler(D&M) � Ring Sample Q Water Level() Approved by: W � Grab Sample � Shelby Tube Sample i Water Level at time ot drilling(ATD) a _ Associated Earth Sciences,Inc. EX loration Lo r;, Project Number Exploration Number Sheet �- �'' � � � KE0807626 EB-3 1 of 1 ( Project Name Hazen High School Addition Ground Surface Elevation(ft) —466' Location Renton. WA Datum Navngg DrilledEquipment Davies Drilling Date StarVFinish .ri/R/f1Q��R/flq � Hammer WeighUDrop 140#/30" Hole Diameter(in) R" c a� w o • u� � L a a E m a� � �n Blows/Foot °' o T in �v� �� `° � — DESCRIPTION " � m �0 20 3o ao �I Topsoil s S-� Mast,dark brown,silty SAND,with organics. - s 79 Vashon Recessional Outwash 13 I Moist,brownish gray,silty fine to medium SAND,with gravel. Moist,slighUy rust-stained brownish gray,silty fine to medium SAND,with 9 S-2 gravel and sandier zones. io 2t . �� I 5 Moist,same,with silt seams. 7 S-3 10 20 �o ( � M I �� Wet,brownish gray,fine SAND,with silty zones and fine to medium sand 34 S-4 beds. ao 5a ' Blow counts overstated-pounded on rock. ta I Water encountered at 1 t'. ( - - - -- ---- - -- ----------- ------- - -- Vashon Ice-Contact I I �5 Wet,rust-stained brownish gray,fine SAND. s S'5 20 � 7 — — 27 Pre-Olympia Fine-Grained Deposits I I 20 S� Moist,Wuish gray,silty fine SAND/sandy S1LT,with trace gravel� � - 501�" Bottom of expbration boring at 20 5 feet I 25 I I 30 I i I 35 o I N fh W � � 1 N Sampler Type(ST): m m 2'OD Split Spoon Sampler(SPT) � No Recovery M-Moisture Logged by: �p� o � 3"OD Split Spoon Sampler(D&M) � Ring Sample Q Water Level() Approved by: W � Grab Sample � Shelby Tube Sample 1 Water Level at time of drilling(ATD) Associated Earth Sciences,Inc. EX loration Lo ;J.�� � � � � � Project Number Exploration Number Sheet ��- ` �° KE0807626 EB-4 1 of 1 Project Name Hazen High Sch�ol Addition Ground Surface Elevation(ft) —467' Loption Renton. WA Datum NAVI�RR � Driiler/Equipment Davies Drilling Date Start/Finish .r,/R/(14�.�,/R/ffq Hammer WeighUDrop 140#I 30�� Hde Diameter(in} F" � N U p O > � tn t o, a E v Q� 3 BIOWS/FOOt � m S cEo �` >' �E a3 o y C7� m � T `� DESCRIPTION � � m �0 20 30 4� � S_� � Topsoil g �6"mast,dark brown,silty SAND,with organics. % �2 �sz Filt � 6"moist,reddish brown,silty SAND,with gravel. ' Moist,slightly rust-stained brownish gray,silty fine to medium SAND,with S-2 gravel. tp �23 Moist,rust-stained brownish gray,silty fine to medium SAND,with gravel �3 and sandier zones. 5 g_3 Moist,brownish gray and rust-colored silty fine to medium SAND,with 19 gravel-pounded on rock. � �� � - Vashon lce-Contact -- - -- ---- i ia � , g.4 Moist,brownish gray,silty fine to medium SAND,with gravel. i� � soi ii ' 15 S 5 Wet,rust-stained brownish gray,stratified fine to medium SAND. g . 15 I 20 � 20 Wet,rust-stained brownish gray,silty fine SAND. �� S� 16 39 -- ----- - 23 Bottom of exploration boring at 21 5 teet No free water 25 I '' 30 1 i i i 35 � � i � ( a � a' c9 ' � Sampler Type(ST): � m 2"OD Split Spoon 5ampler(SPT) Q No Recovery M-Masture Logged by: JPL � m m 3"OD Split Spoon Sampler(D&M) � Ring Sample � Water Level() Approved by: W � Grab Sample � Shelby Tube Sample 1 Water Level at time of drilling(ATD) a Associated Earth Sciences,Inc. EX loration Lo ,.; �' �L Project Number ExploraGon Number Sheet I � 0 � � � KE0807626 EB-5 1 of 1 Project Name Hazen High School Addition Ground Surface Elevation(ft) �468' LocaGon Renton. WA Datum NAVI�RR � DrilierlEquipment Davies Drilling Date StarVFinish �/RI(1q,.�i/R/�9 Hammer WeighVDrop 140#/30�� Hole Diameter(in) g" c a� �„I � m L� � °' � Blows/Foot °' -N J N � S � �T ��� O o T v� �� U � m �I DESCRIPTION to 20 3o ao Topsoil 3 S-� �4"moist,dark brown,silty SAND,with organics. � s �is Filt � I Mast,slightly rust-stained brownish gray,silty fine to medium SAND,with gravel. q S-2 Moist,rust-stained brownish gray,silty fine to medium SAND,with gravef 3 � and sandier zones. a � 5 Moist,rust-stained brownish S-3 9raY.silty fine to medium SAND,with gravel. 25 as ss - - - --- � Vashon Ice-Contact I I �� Moist,rust-stained brownish gray,fine SAND,with silt seams. �� � S� 19 39 � 20 I �� �5 Encountered water at 15'. � I I S-5 Wet,brownish gray,fine SAND. 9 - '1 t 22 11 ---- - - -- - --------------- -- - - - - - - II Vashon Lodgement Till Change at 18'. 20 Moist,slighUy rust-stained brownish gray,silty fine to medium SAND,with 20 I I S-s gravel. 3t 5oM' Botlom of exploration boring at 21 5 feet I I 25 I I I 30 I I 35 o I � M m f � � N Sampler Type{S�: o m 2"OD Split Spoon Sampler(SPT) � No Recovery M-Moisture Logged by: �p� v � 3'OD Split Spoon Sampler(D&M) � Ring Sample SZ Water Level() Approved by: W � Grab Sample Q Shelby Tube Sample 1 Water Level at time of drilling(ATD) Associated Earth Sciences, Inc. � .� ` ��`:� � -. � ��afi�9�1ve�z5 �e��sof�'e�uice , September 11, 2009 Project No. KE080762B Renton School District Capital Projects Office 7812 South 124`� Street Seattle, Washington 98178 Attention: Mr. Stewart L. Shusterman i Subject: Geotechnical Report Addendum � Hazen High School Building Addition � 1101 Hoquiam Avenue NE ! Renton, Washington I � Dear Mr. Shusterman: ' As requested, this letter presents additional observations and recommendations related to the � preparation of the foundation subgrade for the planned Hazen High School building addition. This , addendum addresses the variability of the existing gymnasium foundation elevations as it relates to the foundation design for the new addition. This letter is a supplement to our comprehensive geotechnical engineering report for the project, dated May 15, 2009, and should be used together with that report. Since the publication of our May 15`� report, the addition footprint and slab elevation have been established. A project finished floor elevation of 100 feet has been established for the addition. This project elevation is approximately equal to a ground surface elevation of 468 feet. As-built foundation information for the southerly adjacent gymnasium has also been provided. The as-built information indicates that at least five of the existing gymnasium exterior column pad foundations bear at an eievation higher than the proposed finished floor elevation of the st�bject addition. During a project design meeting, it was determined that these foundations should be exposed to determine the actual bottom of foundation elevation and soil bearing conditions. This addendum � documents this existing foundation investigation, establishes the bearing elevation of aur recent borings (May report) wiih respect to the new addition floor elevation (100 feet), and provides recommendations for new foundation support or subgrade improvement. We visited the subject site on August 24, 2009 to observe exploration pits excavated along the north side of the existing gymnasium immediately to the south of the planned addition. The { explorations were in the area of variable foundation elevations indicated in the original building plans. These explorations exposed a stepped foundation, which included column pad footings with Kirkland ■ Everett ■ Tacoma � 425-827-7701 425-259-0522 253-722-2992 subgrade elevations above and below the proposed slab subgrade elevation of the new addition. The soils exposed in these pits generally consisted of shallow fill overlying weathered and unweathered medium dense native soils below the base of the existing column pads. The attached figure is the "Site and Exploration Plan" from our previous report modified to show the new addition footprint, the project elevation of suitable bearing soils in each of our previous borings, and the bearing elevation of the existing gymnasium column pads encountered during the most recent investigation. These elevations are relative to the new addition planned finished floor elevation of 100 feet. It should be noted that the soils observed above and adjacent to the existing column pads consisted of 3 to 4 feet of loose, debris-laden foundation backfill. Foundation Subgrade - Planned Addition Assuming a new addition foundation bearing elevation of 97 feet (3 feet below top of slab), it appears that approximately 4 to 6 feet of overexcavation or soil subgrade improvement will be needed to reach at least medium dense native soils for much of the planned addition. The following paragraphs present options for the mitigation of the existing fill, topsoil, or loose soils. Overexcavation As stated in our May geotechnical report, overexcavated soils can be replaced with structural fill to restore planned foundation grades. We recommend that existing fill be removed from below areas of planned foundations to expose underlying, undisturbed native sediments, followed by restoration of the planned foundation grade with structural fill. Removal of existing fill should extend laterally beyond the building footprint by a distance equal to the depth of overexcavation. � For example, if existing fill is removed to a depth of 5 feet below a planned footing area, the excavation should also extend laterally S feet beyond the building footprint in that area. Care should be taken not to disturb support soils of existing foundations. Support soils should be considered those soils within a prism projected downward and outward from existing footings at inclinations of 1H:1V (Horizontal:Vertical). Where existing fill is removed and replaced with structural fill, conventional shallow foundations may be used for building support. The required depth of removal should be determined in the field based on actual conditions encountered during excavation. The existing fill removed as part of the overexcavation can be reused as structural fill provided it is cleaned of organic material and debris and moisture-conditioned to within a few percent of the optimum moisture content. Rammed Aggregate Piers An aliemative to overexcavation and replacement of unsuitable foundation soils is the use of Rammed Aggregate PiersT'"(RAPs), which are installed by Geopier Foundation Company. RAPs are formed by inserting a hollow mandrel to a specified depth. Crushed rock is then placed and compacted through the mandrel in thin lifts as the mandrel is withdrawn. The result is a column of compacted aggregate and compaction of soils sunounding the RAPs. RAPs are designed by the convactor who installs them and who determines RAP spacing, depth, and diameter to meet project goals. The exploration included in our May 15, 2009 report can provide a basis for the 2 i design. Conventional shallow foundations are then constructed above the subgrade after R.APs have been installed. i For this project, if RAPs are used, we recommend completing the general excavation and �11 placement recommended in the "Site Preparation" section of our May 15, 2009 report. RAPs can ' then be installed. When RAP installation is complete, the building pad can be cleared of any drill cuttings and fine-graded with structural fill. Footings can then be constructed using standard shallow foundation design and construction methods. For planning purposes, we anticipate that shallow foundations above RAPs could be designed with an allowable foundation soil bearing pressure of 3,000 pounds per square foot (psfl. Foundation footings/keyways surrounded with structural fill may be designed for passive resistance against lateral translation using an equivalent fluid equal to 250 pounds per cubic foot (pcfl. The passive equivalent fluid pressure diagram begins at the top of the footing; however, total lateral resistance should be summed only over the depth of the actual key (truncated triangular diagram). Passive resistance values include a factor of safety equal to 3 in order to reduce the amount of movement necessary to generate passive resistance. The friction coefficient for structures cast directly on structural fill, as described in our May 15, 2009 report, may be taken as 0.30. This is an allowable value and includes a safety factor. The soil under the footings must be recompacted to 95 percent of the above-mentioned standard, as recommended in the "Site Preparation" section of our May 15, 2009 report, for this value to apply. If desired, RAPs could also be used to support the building floor slab. New vs. Existing Foundation Elevations In our May 15, 2009 report, we recommended that, if possible, the new foundations should be founded at the same elevation as the existing foundations. As stated above, recent explorations exposed a stepped foundation along the existing gymnasium to the south of the planned addition. These steps include footings with subgrade elevations above and below the projected foundation ' � and floor slab subgrade elevation of the new addition. Although the attached figure shows the elevation of at least medium dense native soils exposed in the exploration pits along the existing structure, the soils observed within 3 to 4 feet of the existing structure consisted of loose, debris- laden foundation backfill, which extended to the bottom elevation of the existing footings. If new footings are founded above existing footings, they will impart new loads that may lead to settlement of the existing footings. Conversely, if new foundations will be placed below existing footing elevations, the existing elements may need to be underpinned to mitigate the loads from the existing foundation to the new foundation, as well as to mitigate the effects of undermining the existing foundation. The following paragraphs present our recommendations to mitigate both cases of differing foundation subgrade elevations. Existing Foundations Higher Than New Foundations The existing foundations that are above the floor elevation of the addition will likely be incorporated into the walls of the new addition. These elements may need to be underpinned to ' allow vertical excavations below the base of the foundations. Considering the density of the ; natural soils, driven underpinning elements, such as pin piles, will likely not work for foundation � 3 underpinning without costly/time-consuming pre-drilling. Drilled in-place steel beams are a more predictable underpinning method for this application. We are available to provide situation- specific underpinning design recommendations, as required. Alternatively, we recommend that the soil below the existing "high" foundation segments be excavated down to the foundation subgrade elevation of the new addition. These excavations can be completed in short segments (4 to 8 feet in length}, which are subsequently filled with reinforcing and concrete. The actual length and depth of these segments can be adjusted in the field as conditions warrant. This procedure would reduce the risk of undermining the existing footing, as weIl as reduce the lateral loading imparted onto the new addition by the existing structure. We also recommend that the existing structure be monitored for movement before and during the excavation activities. Existing Foundations Lower Than New Foundations Since the soils immediately adjacent to the existing structure consist of debris-laden fill, we recommend that the foundation excavation for the new addition extend to the bottom elevation of the existing footings. Where these existing footings extend below the foundation subgrade elevation of the new addition, the excavation can then be backfilled with either concrete or controlied-density fill (CDF)up to the planned foundation subgrade elevation for the new addition. The use of concrete or CDF would reduce the lateral loading imparted onto the existing foundations by the new addition foundation. We are available to provide an evaluation of lateral loads imparted by the new foundations on the existing foundation on a situation-specific basis. An allowable bearing pressure of 3,000 psf may be used for footings placed directly over trench lines excavated to the medium dense or better native soils, where located at or below the bottom elevation of the existing footings, and backfilled with either concrete or CDF. If you have any questions regarding this letter or other aspects of the project,please do not hesitate ' to call. Sincerely, ASSOCIATED EARTH SCIENCES, INC. M�� � - Kirkland, Washington ,P�o wAsy��'t'�y ��ti �, :, N�,�p2 �•_ 2 � �`�y O� ,9 2358D � �� �` FGISSER� �� , I �� SS�ONAt�� ��._ r �. Je y P. Laub, P.G., P.E.G. Kurt D. Merriman, P.E. Project Engineering Geologist Principal Engineer Attachments: Site and Exploration Plan (with supplemental information) 1PUld-KE08D762D3-Projects120080762\KE1WP 4 � _ � - - ; � � � I ' � � i ' � ; � I � _ :-�_ � ;�, �� ��� ----5��-��- I .�----. � BOTTOM ELEVATION OF ��, - 1 �- FILL!TOPSOIL/ LOOSE '� �-- : �.r-�=`�97' ,._-.-�,_-::o-- —�,m SOILS, TYP � - y� _ �' ` � --;:�,_�:� I --J __--- �ri_--���� ,.�,.:---- 9�� ' ;`EB'' _ r+wi Ti r n�a.� APPROXIMATE LOCATION � • ' I � �� �,a OF EXPLORATI�N BORING EB-2 � .�: TYP I �� aj� � ;� � t� '� � ELEVATION 100'=468'ON i ' _ � � � � TOPOGRAPHIC SURVEY � � � � � j, � 92 � ' � � ' � �EB-4.`�.— - — —�-=---- � � � � � 93' � z , � •,� . � gg � i �EB-5 ; . w a �EB_� � :. :,. . � . .a,� -------- -------- . -� - `" �a.r�--nwu. ---'-�..,n �+ --� � � a..s:=--i.55'.n'---' n.r-v+-=yiiw.: ...� �� � ; "--:�.'.�., k3 „--��,.� . _ ,,.--.�., ' � ---4:��zs�=�_ �99 '/Z' ;100 � �� � APPROXIMATE I APPROXIMATE 1� � � tOCATION OF � LOCATION OF I AUGUST 24, 2009� PROPOSED � I EXPLORATION � ADDITION � ; TYP ' (FINISHED FLOO�t � , � ELEV= 100') ' , � � � _ __ . � ' � � � � LL n ' i N x j � 1 { � , ,F . � A e �y �� �r � �� ;� �� 0 40 80 � � a� t 5 ��� �' � REFERENCE: DLR GROUP 'I' �� ri, i Associated Earth Sciences,Inc. SITE AND EXPLORATION PLAN FIGURE 2 N � `'�'" D ��'� �, � � RENTONHWASH NG ON PROJ.NO. KE080762B APPENDIX D Bond Quantities Facility Summaries Declaration of Covenant COUGHLIN PORTER LUNDEEN Hazen HS Classroom Addition Web date: 11/28/2007 Site Improvement Bond Quantity Worksheet � King County Department of Development & Environmental Services 900 Oakesdale Avenue Southwest Renton, Washington 98057-5212 For alternate formats, call 206-296-6600. 206-296-6600 TTY 206-296-7217 Project Name: Hazen High School Classroom Addition �ate: 12/15/2009 �ocation: 1101 Hoquiam Ave NE, Renton, WA, 98059 Project No.: C090125-02 Actfvity No.: Note: All prices include labor, equipment, materials, overhead and Clearing greater than or equal to 5,000 board feet of timber? profit. Prices are from RS Means data adjusted for the Seattle area or from local sources if not included in the RS Means database. yes X no If yes, Forest Practice Permit Number: (RCW 76.09) Page 1 of 9 Unit prices updated: 02/12/02 Version: 04/22/02 Bond Quantity Worksheet.xfs Report Date: 12/15/2009 Site Improvement Bond Quantity Worksheet Webdate: 11/28/2007 Unit #of Reference# Price Unft Quanti Ifcations Coat ERO 1 N/SEDIMENT CONTROL Number Backfill&compaction-embankment ESC-1 $ 5.62 CY Check dams,4" minus rock ESC-2 SWDM 5.4.6.3 $ 67.51 Each Crushed surfacin 1 1/4"minus ESC-3 WSDOT 9-03.9 3 $ 85.45 CY Ditchin ESC-4 $ 8.08 CY Excavation-bulk ESC-5 $ 1.50 CY Fence, silt ESC-6 SWDM 5.4.3.1 $ 1.38 LF 160 1 221 Fence,Tem ora NGPE ESC-7 $ 1.38 LF 1550 1 2139 H droseedin ESC-8 SWDM 5.4.2.4 $ 0.59 SY Jute Mesh ESC-9 SWDM 5.4.2.2 $ 1.45 SY Mulch, b hand, straw, 3"dee ESC-10 SWDM 5.4.2.1 $ 2.01 SY Mulch, b machine, straw,2"dee ESC-11 SWDM 5.4.2.1 $ 0.53 SY Pi in ,tem ora ,CPP, 6" ESC-12 $ 10.70 LF Pi in ,tem ora , CPP,8" ESC-13 $ 16.10 LF Pipin , tem ora , CPP, 12" ESC-14 $ 20.70 LF Plastic coverin , 6mm thick, sandba ed ESC-15 SWDM 5.4.2.3 $ 2.30 SY Ri Ra , machine laced; slo es ESC-16 WSDOT 9-13.1 2 $ 39.08 CY Rock Construction Entrance, 50'x15'x1' ESC-17 SWDM 5.4.4.1 $ 1,464.34 Each Rock Construction Entrance, 100'x15'x1' ESC-18 SWDM 5.4.4.1 $ 2,928.68 Each 1 1 2929 Sediment ond riser assembl ESC-19 SWDM 5.4.5.2 $ 1,949.38 Each Sedimenttra , 5' hi h berm ESC-20 SWDM 5.4.5.1 $ 17.91 LF Sed.trap,5'high,riprapped spiliway berm section ESC-21 SWDM 5.4.5.1 $ 68.54 LF Seedin , b hand ESC-22 SWDM 5.4.2.4 $ 0.51 SY Soddin , 1"dee , level round ESC-23 SWDM 5.4.2.5 $ 6.03 SY Soddin , 1"deep, slo ed round ESC-24 SWDM 5.4.2.5 $ 7.45 SY TESC Su ervisor ESC-25 $ 74.75 HR Wator truck, dust control ESG26 SWDM 5.4.7 $ 97.75 HR WRIT -IN-ITEMS '"*** see a e 9 Baker Tanks $ 7,500.00 Each 2 1 15000 ESC SUBTOTAL: $ 20,288.48 30%CONTINGENCY& MOBILIZATION: $ 6,086.54 ESC TOTAL: $ 26,375.02 COLUMN: A Page 2 of 9 Unit prices updated: 02/12/02 Version: 04/22/02 Bond Quantity Worksheet.xls Report Date: 12/15/2009 Site Improvement Bo� Quantity Worksheet Webdate• 912007 �xisting F'uture Publlc Private fluantity Completed Right-of-Way Road Improvements improvements (Bond Reductlon)• II � &Draina e Facllitles Quant. I Unit Price Unit Quant. Cost Quant. Cost Quant. Cost Com tete Cost I G No. Backfiil&Com action-embankment GI-1 $ 5.62 CY 1268 7,126.16 Backfill&Com action-trench GI-2 $ 8.53 CY , Clear/Remove Brush,b hand GI-3 $ 0.36 SY Clearin /Grubbin /Tree Removal GI-4 $ 8,876.16 Acre 0.82 7,278.45 Excavation-bulk GI-5 $ 1.50 CY 8708 13,062.00 Excavation-Trench GI-6 $ 4.06 CY Fencin ,cedar,6'hi h GI-7 $ 18.55 LF Fencin ,chain link,vin I coated, 6'hi h GI-8 $ 13.44 LF Fencin ,chain link, ate,vin I coated, 20' GI-9 $ 1,271.81 Each Fencin ,s lit rail,3'hi h GI-10 $ 12.12 LF Fill 8 com act-common barrow GI-11 $ 22.57 CY Fill&com act- ravel base GI-12 $ 25.48 CY Fill&com act-screened to soil GI-13 $ 37.85 CY Gabion,12"dee ,stone filled mesh GI-14 $ 54.31 SY Gabion,18"dee ,stone filied mesh GI-15 $ 74.85 SY Gabion.36"dee ,stone filled mesh GI-16 $ 132.48 SY Gradin ,fine,b hand GI-17 $ 2.02 SY Gradin ,fine,with rader GI-18 $ 0.95 SY 6700 6,365.00 Monuments,3'lon GI-19 $ 135.13 Each Sensitive Areas Si n GI-20 $ 2.88 Each Soddin ,1"dee ,slo ed round GI-21 $ 7.46 SY Surve in ,line& rade GI-22 $ 788.26 Da Surve in ,lot location/lines GI-23 $ 1,556.64 Acre Traffic control crew 2 fla ers GI-24 $ 85.18 HR Trail,4"chi ed wood GI-25 $ 7.59 SY Trail,4"crushed cinder GI-26 $ 8.33 SY Trail,4"to course GI-27 $ 8.19 SY Wall,retainin ,concrete GI-28 $ 44.16 SF Wall,rockery GI-29 $ 9.49 SF Page 3 of 9 SUBTOTAL 33,831.61 Unit prices updated: 02/12/02 'KCC 27A authorizes only one bond reduction. Version: 4/22/02 Bond Quantity Worksheet.xls Report Date: 12/15/2009 Site Improvement Boi Quantity Worksheet Webdate• 9/2007 �� Exiatinp Future Public Private Bond Reduction• Right-of•way Road Improvements Improvements 8�Dralna e Facllities Quant. Unit Price Unit Quant. Cost Quant Cost Quant. Cost Com lete Cost M R N . AC Grindin ,4'wide machine< 1000s RI-1 $ 23.00 SY 355 8 165.00 AC Grindin ,4'wide machine 1000-2000s RI-2 $ 5.75 SY AC Grindin ,4'wide machine>2000s RI-3 $ 1.38 SY AC Removal/Dis osal/Re air RI-4 $ 41.14 SY 562.0 23,120.68 Barricade, e I RI-5 $ 30.03 LF Barricade, e III Permanent RI-6 $ 45.05 LF Curb&Gutter,rolled RI-7 $ 13.27 LF Curb 8 Gutter,vertical RI-8 $ 9.69 LF Curb and Gutter,demolition and dis osal RI-9 $ 13.58 LF Curb,extruded as halt RI-10 $ 2.44 LF Curb,extruded concrete RI-11 $ 2.56 �F 453 1,159.68 Sawcut,as halt,3"de th RI-12 $ 1.85 LF 719 1,330.15 Sawcut,concrete, er 1"de th RI-13 $ 1.69 LF Sealant,as halt RI-14 $ 0.99 LF 200 198.00 Shoulder,AC, see AC road unft rice RI-15 $ - SY I Shoulder, ravel,4"thick RI-16 $ 7.53 SY Sidewalk,4"thick RI-17 $ 30.52 SY 1366 41,690.32 Sidewalk,4"thick,demolition and dis osal RI-18 $ 27.73 SY 750 20,797.50 Sidewalk,5"thick RI-19 $ 34.94 SY Sidewalk,5"thick,demolition and dis osal RI-20 $ 34.65 SY Si n,handica RI-21 $ 85.28 Each 1 85,28 Stri in , er stall RI-22 $ 5.82 Each 26 151.32 Stri in ,thermo lastic, for crosswalk RI-23 $ 2.38 SF Striping,4"reflectorized line RI-24 $ 0.25 LF Page 4 of 9 SUBTOTAL 96,697.93 I' Unit prices updated: 02/12/02 'KCC 27A authorizes only one bond reduction. VersiOn: 4/22/02 Bond Quantity Worksheet.xls Report Date: 12/15/2009 ___ __. _ _ __ . _ __ � Web date 3/2007 II Site Improvement Bo� . _. Quantity Worksheet Exlsting Future Public Pr(vate Bond Reduction' Right-of-way Road improvements Improvements &Draina e Facilitles Quant. Unit Price Unit Quant. Cost Quant. Cost Quant. Cost Com lete Cost U FA (4"Rock=2.5 base&1.5"top course) For'93 KCRS(6.5"Rock=5"base&1.5"top course) For KCRS'93, additional 2.5"base add: RS-1 $ 3.60 SY AC Overla , 1.5"AC RS-2 $ 7.39 SY AC Overla ,2"AC RS-3 $ 8.75 SY 355 3,106.25 AC Road,2",4"rock,First 2500 SY RS-4 $ 17.24 SY AC Road,2",4"rock,Qt .over 2500SY RS-5 $ 13.36 SY AC Road,3",4"rock,First 2500 SY RS-6 $ 19.69 SY 282 5,552.58 AC Road,3",4"rock,Q .over 2500 SY RS-7 $ 15.81 SY AC Road,5",First 2500 SY RS-8 $ 14.57 SY AC Road,5",Q .Over 2500 SY RS-9 $ 13.94 SY AC Road,6",First 2500 SY RS-10 $ 16.76 SY AC Road,6",Q .Over 2500 SY RS-11 $ 16.12 SY As halt Treated Base,4"thick RS-12 $ 9.21 SY � Gravel Road,4"rock,First 2500 SY RS-13 $ 11.41 SY ' Gravel Road,4"rock,Qt .over 2500 SY RS-14 $ 7.53 SY PCC Road,5",no base,over 2500 SY RS-15 $ 21.51 SY PCC Road, 6",no base,over 2500 SY RS-16 $ 21.87 SY Thickened Edge RS-17 $ 6.89 LF Page 5 of 9 SUBTOTAL 8,658.83 Unit prices updated: 02/12/02 `KCC 27A authorizes only one bond reduction. VefsiOn: 4/22/02 Bond Quantity Worksheet.xls Report Date: 12/15/2009 Site Improvement Bo� Quantity Worksheet Webdate 9I2007 Existing Future Public Private Bond Reductlon` Rfght-of-way Road Improvements Improvemenb &Dralna a Faciiities Quant. Unit Price Unit Quant. Cost Duant. Cost Quant. Cost Com lete Cost A (CPP�Corrugated PlasUc Pipe,N12 or Equivalent) For Culvert ces, Avera of 4'cover was assumed.Assume rforated PVC Is same rice as sol�d i . Access Road,R/D D-1 $ 16.74 SY Bollards-fixed D-2 $ 240.74 Each Bollards-removable D-3 $ 452.34 Each ' CBs include frame and lid CB T e I D-4 $ 1,257.64 Each 5 6,288.20 CB T e IL D-5 $ 1,433.59 Each CB T e II,48"diameter D-6 $ 2,033.57 Each 5 10,167.85 for additional de th over 4' D-7 $ 436.52 FT 22 9,603.44 CB T e II,54"diameter D-8 $ 2,192.54 Each for additional de th over 4' D-9 $ 486.53 FT CB T e II,60"diameter D-10 $ 2,351.52 Each for additional de th over 4' D-11 $ 536.54 FT CB T e II,72"diameter D-12 $ 3,212.64 Each for additional de th over 4' D-13 $ 692.21 FT Throu h-curb Inlet Framework Add D-14 $ 366.09 Each Cleanout,PVC,4" D-15 $ 130.55 Each Cleanout,PVC,6" D-16 $ 174.90 Each 15 2,623.50 Cleanout,PVC,8" D-17 $ 224.19 Each Culvert,PVC,4" D-18 $ 8.64 LF Culvert,PVC,6" D-19 $ 12.60 LF 355 4,473.00 Culvert,PVC, 8" D-20 $ 13.33 LF 196 2,612.68 Culvert,PVC, 12" D-21 $ 21.77 LF 390 8,490.30 Culvert,CMP,8" D-22 $ 17.25 LF Culvert,CMP,12" D-23 $ 26.45 LF Culvert,CMP,15" D-24 $ 32.73 LF Culvert,CMP,18" D-25 $ 37.74 LF Culvert,CMP,24" D-26 $ 53.33 LF Culvert,CMP,30" D-27 $ 71.45 LF Culvert,CMP,36" D-28 $ 112.11 LF Culvert,CMP,48" D-29 $ 140.83 �F Culvert,CMP,60" D-30 $ 235.45 LF Culvert,CMP.72" D-31 $ 302.58 LF Page 6 of 9 SUBTOTAL 44,258.97 Unit prices updated: 02/12/02 `KCC 27A authorizes only one bond reduction. Version: 4/22/02 Bond Quantiry Worksheet.xls Report Date: 12/15/2009 Site Improvement Boi . . Quantity Worksheet Webdate: 312007 Exlsting Future Public Phvate Bond Reduction* RigM•of-way Road Improvements improvementa N I UED &Orafnage Facilities Quant. No. Unit Price Unit Quant. Cost Quant. Cost Quant. Cost Com lete Cost Culvert,Concrete,8" D-32 $ 21.02 LF Culvert,Concrete,12" D-33 $ 30.05 LF I Culvert,Concrete,15" D-34 $ 37.34 LF Culvert,Concrete,18" D-35 $ 44.51 LF Culvert,Concrete,24" D-36 $ 61.07 LF Culvert,Concrete,30" D-37 $ 104.18 LF Culvert,Concrete,36" D-38 $ 137.63 LF Culvert,Concrete,42" D-39 $ 158.42 LF Culvert,Concrete,48" D-40 $ 175.94 LF Culvert,CPP,6" D-41 $ 10.70 LF Culvert,CPP,8" D-42 $ 16.10 LF Culvert,CPP, 12" D-43 $ 20.70 LF Culvert,CPP,15" D-44 $ 23.00 LF Culvert,CPP,18" D-45 $ 27.60 LF ' Culvert,CPP,24" D-46 $ 36.80 LF Culvert,CPP,30" D-47 $ 48.30 LF Culvert,CPP,36" D-48 $ 55.20 LF Ditchin D-49 $ 8.08 CY Flow Dis ersal Trench 1,436 base+ D-50 $ 25.99 LF French Drain 3'de th D-51 $ 22.60 LF Geotextile,laid in trench, ol ro lene D-52 $ 2.40 SY Infiltration ond testin D-53 $ 74.75 HR Mid-tank Access Riser,48"dia, 6'dee D-54 $ 1,605.40 Each Pond Overflow S illwa D-55 $ 14.01 SY Restrictor/Oil Se arator, 12" D-56 $ 1,045.19 Each Restrictor/Oil Se arator, 15" D-57 $ 1,095.56 Each Restrictor/Oil 5e arator, 18" D-58 $ 1,146.16 Each Ri ra , laced D-59 $ 39.08 CY Tank End Reducer 36"diameter D-60 $ 1,000.50 Each Trash Rack, 12" D-61 $ 211.97 Each Trash Rack, 15" D-62 $ 237.27 Each Trash Rack, 18" D-63 $ 268.89 Each Trash Rack,21" D-64 $ 306.84 Each Page 7 of 9 SUBTOTAL Unit prices updated: 02/12/02 'KCC 27A authorizes only one bond reduction. VerSion: 4/22/02 Bond Quantity Worksheet.xls Report Date: 12/15/2009 Site Improvement Bor . . Quantity Worksheet �/ebdate: t/2007 Existing Future Public Private Bbnd Reduction` Right-nf•way Road Improvements Improvements 8�Draina e FacfUties Quant Unit price Unit Quant. Price Quant, Cost Quant. Cost Com lete Cost T No. 2"AC,2"to course rock&4"borrow PL-1 $ 15.84 SY 2"AC, 1.5" to course 8 2.5"base course PL-2 $ 17.24 SY 4"select borrow PL-3 $ 4.55 SY 1.5"to course rock 8 2.5"base course PL-4 $ 11.41 SY TE- No. 6-inch Perf Pi e W I-1 $ 13.00 LF 175 2,275.00 Rain Garden WI-2 $ 7.00 SF 1547 10,829.00 Detention Vault WI-3 $ 20,000.00 EA 1 20,000.00 WI-4 WI-5 WI-6 WI-7 WI-8 WI-9 wl-10 SUBTOTAL 33,104.00 SUBTOTAL(SUM ALL PAGES): 216,551.34 30%CONTINGENCY&MOBILIZATION: 64,965.40 G RANDTOTAL: 281,516.74 COLUMN: B C D E Page 8 of 9 Unit prices updated: 02/12/02 'KCC 27A authorizes only one bond reduction. Version: 4/22/02 Bond Quantiry Worksheet.xls Report Date: 12/15/2009 Web date: 11/28/2007 Site Improvement Bond Quantity Worksheet Origlnal bond computations prepared by: Name: Hazen High School Classroom Addition �ate: 12/15/2009 PE Registration Number: Tel.#: 206-343-0460 Firm Name: Coughlin Porter Lundeen nddress: 413 Pine Street Suite 300 Seattle, WA 98101 Project No: C090125-02 ROAD IMPROVEMENTS&DRAINAGE FACILITIES FINANCIAL GUARANTEE REQUIREMENTS PERFORMANCE BOND' PUBLIC ROAD&DRAINAGE AMOUNT BOND`AMOUNT MAINTENANCE/DEFECT BOND' REQUIRED AT RECORDING OR Stabilization/Erosion Sediment Control (ESC) (A) $ 26,375.0 TEMPORARY OCCUPANCY�•• Existing Right-of-Way improvements (B) $ - Future Public Road Improvements& Drainage Facilitie (C) $ - Private Improvements (D) $ 281,516.7 Calculated G�uantity Completed (E) $ - Total Right-of Way and/or Site Restoration Bond'/" (A+B) $ 26,375.0 (First$7,500 of bond'shall be cash.) Pertormance Bond`Amount (A+B+C+D) = TOTAL (T) $ 307,891.8 T x 0.30 $ 92,367.5 OR mimum on amoun is . Reduced Performance Bond"Total"" (T-E) $ 307,891.8 Use larger o x o or - �B+C)x Maintenance/Defect Bond"Total 0.25= $ - NAME OF PERSON PREPARING BOND`REDUCTION: Date: 'NOTE: The word"bond"as used in this document means any financial guarantee acceptabte to King County. "NOTE: KCC 27A authorizes right of way and site restoration bonds to be combined when both are required. 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 KCC 27A,total bond amounts remaining after reduction shall not be less than 30%of the original amount(T)or as revised b ma�or design changes. SURETY BOND RIDER NOTE: If a bond rider is used, minimum additional performance bond shall be $ 281,516.7 (C+D)-E REQUIRED BOND*AMOUNTS ARE SUBJECT TO REVfEW AND MODIFICATION BY DDES Page 9 of 9 Unit prices updated: 02/12/02 Check out the DDES Web site at www.kinsrcountv.s�ov/aermits Version: 4/22/02 Bond Quantity Worksheet.xls Report Date: 12/15/2009 K1NG COUNTY, WASHINGTON, SURFACE WATER DESIGN MANUAL STORMWATER FACILITY SUMMARY SHEET DDES Permit Number (provide one Stormwater Facility Summary Sheet per Natural Discharge Location) Overview: Proiect Name �Hazen High Schooi Classroom Addition Date November 04, 2009 Downstream Drainage Basins Major Basin Name _May Creek Immediate Basin Name Flow Control: Fiow Control Facility Name/Number_DetentiOn Vault Facility Location Center of new courtyard If none, , Flow control provided in regionaUshared facility (give location) No flow control required Exemption number General Facility Inforroation: Type/Number of detention facilities: Type/Number of infiltration facilities: _ponds ponds : 1 vaults tanks tanks trenches Control Structure Location Vault outlet Type of Control Structure _Outlet control riser Number of OrificeslRestrictions Size of Orifice/Restriction: No. 1 0.5 in No.2 No. 3 No.4 Flow Control Performance Standard predeveloped conditions 20�9 Surface Water Design Manual 1/9/2009 1 � KING COUNTY, WASHII�'GTON, SURFACE WATER DESIGN MANUAL Live Storage Volume_ 17,850 Cf _ Depth _6 ft Volume Factor of Safety Number of Acres Served Number of Lots Dam Safety Regulations(Washingtoo State Department of Ecology) Reservoir Volume above natural grade Depth of Reservoir above natural grade Facility Summary S6eet Sketch All detention, infiltration and water quality facilities must include a detailed sketch. (I 1"x17" reduced size plan sheets may be used) � 20()9 Surface Water Design Nfanual 1/9/2009 2 KING COUNTY, WASHINGTON, SURFACE WATER DESIGN MANUAL Water Quality: Type/Number of water quality facilitiesBMPs: biofiltration swale sand filter(basic or large) (regular/wed or continuous inflow) sand filter, linear(basic or large) combined detention/wetpond sand filter vault (basic or large) (wetpond porcion basic or large) sand bed depth (inches) comhined detention/wetvault stormwater wetland , filter strip storm filter flow dispersion wetpond (basic or large) farm management plan wetvault landscape management plan Is faciliry Lined? oil/water separator If so,what marker is used � above (baffle or coalescing plate) Liner? catch basin inserts: Manufacturer pre-settling pond pre-settling structure: Manufacturer high flow byr - . .� source contm f)l'Jlbil dL'11U7I11iiilU;f Water Quality design flow Water Quality treated volume (sandfilter) Water Quality storage volume (wetpool) Facility Summary Sheet Sketch 2009 Surface Water Design Manual 1/92009 3 KING COUNTY, WASHINGTON, SURFACE WATER DESIGN MANUAL All detention, infiltration and water quality facilities must include a detailed sketch. (1 l"x17" reduced size plan sheets may be used) � 2009 Surface Water Desig�Manual 1/9/2009 4 RECORDING REQUESTED BY AND WHEN RECORDED MAIL TO: Coughlin Porter Lundeen attn: Colleen Poling 413 Pine St Suite 300 Seattle, WA 98101 (206) 343-0460 DECLARATION OF COVENANT FOR MAINTENANCE AND INSPECTION OF FLOW CONTROL BMPS IN CONSIDERATION of the following approved King County(check one of the following) _residential building permit, X commercial building pernut,_clearing and grading permit,_ subdivision permit, or_short subdivision pernut for Application No. relating to real property("Property")designated as Tax Parcel No. 1023059072 and legally described as follows: S '/2 OF FOLG —NW '/ of NW '/.of NE '/< less N 15 ft less cord less S 132 ft of E 300 ft THOF the Grantor(s),the owner(s) in fee of the above described parcel of land, hereby covenants(covenant)with , King County, a political subdivision of the state of Washingrton and its municipal successars in interest and assigns ("King County" and"the County", or"its municipal successor"),that he/she(they)will II observe,consent to, and abide by the conditions and obligations set forth and described in Paragraphs 1 ' through 8 below with regard to the Property. Grantor(s)hereby grants(grant), covenants(covenant), and agrees(agree) as follows: 1. Grantor(s)or his/her(their) successors in interest and assigns ("Owners") shall retain, uphold, and protect the stormwater management devices, features,pathways, limits, and restrictions, known as l flow control best management practices("BMPs"), shown on the approved Flow Control BMP Site Plan for the Property attached hereto and incorporated herein as Exhibit A. 2.The Owners shall at their own cost,operate,maintain, and keep in good repair,the Property's BMPs as described in the approved Design and Maintenance Details for each BMP attached hereto and incorporated herein as Exhibit B. 3. King County shall provide at least 30 days written notice to the Owners that entry on the Property is planned for the inspection of the BMPs.After the 30 days,the Owners shall allow King County to enter . for the sole purpose of inspecting the BMPs. In lieu of inspection by the County,the Owners may elect to engage a licensed civil engineer registered in the state of Washington who has expertise in drainage to inspect the BMPs and provide a written report describing their condition. If the engineer option is chosen, the Owners shall provide written notice to the Director of the Water and Land Resources Division or its municipal successor in interest ("WLR")within fifteen days of receiving the County's notice of inspection.Within 30 days of giving this notice,the Owners, or the engineer on behalf of the Owners, shall provide the engineer's report to WLR. If the report is not provided in a timely manner as specified above, the County may inspect the BMPs without further notice. 4. If King County deternunes from its inspection, or from an engineer's report provided in accordance with Paragraph 3,that maintenance,repair,restoration,and/or mitigation work is required for the BMPs, WLR shall notify the Owners of the specific maintenance,repair, restoration, and/or mitigation work(Work) required under Title 9 of the King County Code("KCC"). WLR shall also set a reasonable deadline for completing the Work or providing an engineer's report that verifies completion of the Work. After the deadline has passed,the Owners shall allow the County access to re-inspect the BMPs unless an engineer's report has been provided verifying completion of the Work. If the work is not completed properly within the timeframe set by WLR,King County may initiate an enforcement action. Failure to � properly maintain the BMPs is a violation of KCC Chapter 9.04 and may subject the Owners to III enforcement under the KCC,including fines and penalties. I 5. Apart from perfom�ing routine landscape maintenance,the Owners are hereby required to obtain ' written approval from WLR before performing any alterations or modifications to the BMPs. , � 6.Any notice or approval required to be given by one party to the other under the provisions of this Declaration of Covenant shall be effective upon personal delivery to the other party, or after three(3) �' days from the date that the notice or approval is mailed with Delivery Confirniation to the current address ;' on record with each Party.The parties shall notify each other of any change to their addresses. ; 7.This Declaration of Covenant is intended to promote the efficient and effective management of surface , water drainage on the Property, and it shall inwe to the benefit of all the citizens of King County and its municipal successors and assigns.This Declaration of Covenant shall run with the land and be binding upon Grantor(s), and Grantor's(s')successors in interest and assigns. 8.This Declaration of Covenant may be terminated by execution of a written agreement by the Owners and King County that is recorded by King County in its real property records. i IN WITNESS WHEREOF,this Declaration of Covenant for the Maintenance and Inspection of Flow Control BMPs is executed this day of , 20_ i By Its By Its � STATE OF WASHINGTON) )SS COLJNTY OF KING ) On this day of , 20_,before me,the undersigned, a Notary Public in and for the State of , duly commissioned and swom personally appeared,to me known to be the individual(s)described in and who executed the foregoing instrument, and acknowledged to me that they signed and sealed the said instrument as their free and } voluntary act and deed for the uses and purposes therein mentioned. WITNESS my hand and official seal hereto affixed the day and year in this certificate above written. � Printed name Notary Public in and for the State ' of Washington,residing at My appointment expires APPENDIX E Operations and Maintenance Manual COUGHLIN PORTER LUNDEEN Hazen HS Classroom Addition ,APPENDIX A MAIVTLVAT�CE REQUIREMENTS FOR FLOV4'CONTROL,CONVEYANCE,AI�D WQ FACILITIES NO. 2- INFILTRATION FACILITIES � Maintenance Defect or Problem Conditions When Maintenance Is Needed Results Expected When � Component Maintenance Is Performed Infiltration Pond Trash 8 Debris See"Detention Ponds"Table No. 1 See"Detention Ponds"Table No. 1 General Poisonous Vegetation See"Detention Ponds"Table No. 1 See"Detention Ponds"Table No. 1 or Noxious Weeds Contaminants and See"Detention Ponds"Table No. 1 See"Detention Ponds"Table No. 1 � Pollution Unmowed See"Detention Ponds"Table No. 1 See"Detention Ponds"Table No. 1 GrasslGround Cover Rodent Holes See"Detention Ponds"Table No. 1 See"Detention Ponds"Table No. 1 Insects See"Detention Ponds"Tabte No. 1 See"Detention Ponds"Table No. 1 infiitration Pond Erosion See"Detention Ponds"Table No. 1 See"Detention Ponds"Table No. 1 5ide Slopes Infiltration Pond Tree Growth See"Detention Ponds"Tabie No. 1 See"Detention Ponds"Table No. 1 Emergency Overflow Spillway and Berms over 4 feet in height. j Infittration Pond Rock Missing See"Detention Ponds"Table No. 1 See"Detention Ponds"Table No. 1 � Emergency Overflow Spillway Infiltration Facility Sediment A percolation test pit(ponds)or test of facility Sediment is removed and/or facility ' Storage Area indicates facility is only working at 90%of its is cleaned so that infiltration system designed capabilities. If two inches or more works according to design. Ponds sediment is present,remove. are reseeded if necessary to control erosion. Infiltration Facility Sediment and Debris By visual inspection,little or no water flows Replaced gravel in rock filter. Rock Filters through filter during heavy rain storms. (If Applicable) � Infiltration Facility Sump Filled with Any sediment and debris filling vault to 10%of Clean out sump to design depth. �!� Sump Sediment and Debris depth from sump bottom to bottom of outlet pipe (If Applicable) or obstructing flow into the connector pipe. � Infiltration Facility Filled with Sediment Sediment and debris fill bag more than'/z full. Replaced filter bag or redesign ! Filter Bags and Debris system. � (If Applicable) Infiltration Facility Sediment Remove when 6"or more. Sediment cleaned out to designed Pre-settling Ponds pond shape and depth or sediment and Vaults is removed from vault. Ponds are reseeded if necessary to control erosion. Note: Sediment accumulation of more than 0.25 inches per year may indreate excessive erosion is occurring upstream of fhe facility or that conveyance systems are not being properly maintarned. The contributing drainage area should be checked for erosion problems or inadequate maintenance of conveyance systems ii excessive sedimentation is noted in an infiltration facility. : Check twice a year during first 2 years of operation;once a year thereafte�. Gean manholes/catch basins, repair damaged inlets/outlets, ' clean trash racks. 2005 Surface Water Design Manual-Appendix A l/24!2005 �� ,a-� I APPf:NDIX A MAINTE\ANCE REQUIREMENTS FLO��'CONZROL,CONVEYANCE,AT�D��'Q FACILITIES NO. 3- DETENTION TANKS AND VAULTS Maintenance Defect or Probiem Conditions When Maintenance is Needed Results Expected When � Component Maintenance is Performed Storage Area Plugged Air Vents One-half of the cross section of a vent is biocked Vents free of debris and sedime�t at any pant with debris and sediment. Debris and Sediment Accumulated sediment depth exceeds 10%of All sediment and debris removed the diameter of the storage area for Yz length of from storage area. storage vault or any point depth exceeds 15%of diameter. Example:72-inch storage tank would require cleaning when sediment reaches depth of 7 inches for more than'/:length of tank. Joints Between Any crack allowing material to be transported into All joint between tank/pipe sections Tank/Pipe Section facility. are sealed Tank Pipe Bent Out of Any part of tank/pipe is bent out of shape more Tank/pipe repaired or replaced to Shape than 10%of its design shape. design. Vault Structure Damage to Wall, Cracks wider than Yrinch and any evidence of Vault replaced or repaired to design Frame,Bottom, soil particles entering the structure through the specifications. and/or Top Slab cracks,or maintenance inspection personnel determines that the vault is not structurally sound. Damaged Pipe Joints Cracks wider than Yrinch at the joint of any No cracks more than Y.-inch wide at inleUoutlet pipe or any evidence of soil particles the joint of the inleVoutlet pipe. entering the vault through the walls. Manhole Cover Not in Place Cover is missing or only partially in place.Any Manhole is closed. open manhole requires maintenance. , Locking Mechanism Mechanism cannot be opened by one Mechanism opens with proper tools. Not Working maintenance person with proper tools. Bolts into frame have less than Y�inch of thread(may not apply to self-locking lids.) Cover DiKcult to One maintenance person cannot remove lid after Cover can be removed and Remove applying 801bs of lift. Intent is to keep cover from reinstalted by one maintenance sealing off access to maintenance. person. Ladder Rungs Unsafe King County Safety Office andlor maintenance Ladder meets design standards. person judges that ladder is unsafe due to Allows maintenance person safe � missing rungs,misalignment,rust,or cracks. access. Large access Gaps,Dcesn't Cover Large access doors not flat andlor access hole Doors closes flat and covers access doors/plate Completely not completely covered. NOTE however that hole completely. grated doors are acceptable. Lifting Rings Missing, Lifting rings not capable of lifting weight of door Lifting rings sufficient to remove tid. Rusted or lid. I;Z4i2005 2005 Surface�Vater Design Manual-Appendix A A-4 APPENDIX A MAINTENANCE REQUIREMENTS FOR FLOW CONTROL,CONVEYANCE,AND WQ FACILITIES 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. � , Structuraf 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 overFlow pipe. works as designed. Manhnle See"Detention Tanks See"Detention Tanks and Vaults"Table No.3 See"Detention Tanks and Vaults" and Vaults" Table No.3 �_ i €- � -, � - � I r a a J !_ 2005 Surface Water Design Manual-Appendix A ]/24/2005 A-5 APPENDIX A I�9AINTENANCE REQUIREv1ENTS 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 General Trash 8 Debris Trash or debris of more than'/z 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 '/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 iniet or outlet pipe blocking Inlet and outlet pipes free of trash or more than'/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). Deposits 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'/.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%inch and longer than 3 feet, Basin replaced or repaired to design WallslBottom any evidence of soil particles entering catch standards. basin through cracks,or maintenance person judges that structure is unsound. Cracks wider than Yz inch and longer than 1 foot No cracks more than'la inch wide at at the joint of any inleUoutlet pipe or any the joint of inleUoutlet pipe. e�idence of soil particles entering catch basin through cracks. SettlemenV 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 inleUoutlet pipe joints that No vegetation or root growth is more than 6 inches tall and less than 6 inches present. apart. Pollution Nonflammable chemicals of more than Y�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%:inch of thread. Cover Di�cult 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. 1i24/2005 2005 Surface Water Design Manua]-Appendir 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�/e inch. Grate opening meets design (If Applicable) Opening standards. i 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 DamagedlMissing 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 and rust is causing 50% Repair or replace barrier to design deterioration to any part of barrier. standards. NO. 7- ENERGY DISSIPATERS Maintenance Defect or Problem Conditions When Maintenance is Needed Results Expected When Component Maintenance is Performed. Extemai: Rock Pad Missing or Moved Only one layer of rock exists above native soil in Replace rocks to design standards. 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 cleaned/flushed so that it Sediment design depth. matches design. Not Discharging Visual evidence of water discharging at Trench must be redesigned or Water Properiy concentrated points along trench(normal rebuilt to standards. condition is a"sheet flowl'of water along trench). Intent is to prevent erosion damage. Perforations Plugged. Over'/:of perforations in pipe are plugged with Clean or replace perforated pipe. debris and sediment. Water Flows Out Top Maintenance person observes water flowing out Facility must be rebuilt or of"Distributor"Catch during any storm less than the design storm or redesigned to standards. Basin. its causing or appears likely to cause damage. Receiving Area Over- Water in receiving area is causing or has No danger of landslides. Saturated potential of causing landslide problems. Intemal: Manhole/Chamber Worn or Damaged Structure dissipating flow deteriorates to'/z or Replace structure to design Post. Baffles, Side of original size or any concentrated worn spot standards. Chamber exceeding one square foot which would make structure unsound. 2005 Surface Vb'ater Design Manual-Appendix A Ii24�2005 .A-7 APPENDIX A �4AINTENANCE REQUIREIvIENTS FLOW CONTROL,CONVEYANCE,.4ND 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 1Y�inches. Top raiis 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 a�ignment. 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 2Y�inches between posts. 'h inch sag between post. Extension arm missing,broken,or bent out of Extension arm in piace with no shape more than 1'/�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 Performed 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-b � j 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 8�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 Ail vegetation removed so 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 8 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 Ponds'Table No. 1 Slopes Rock Lining Out of Maintenance person can see native soil beneath Replace rocks to design standards. Place or Missing(ff the rock lining. � Applicable). NO. 11 -GROUNDS (LANDSCAPING) Maintenance Defect or Problem Conditions When Maintenance is Needed Results Expected When i Component Maintenance is Pertormed � General Weeds Weeds growing in more than 20%of the Weeds present in less 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. tandscaped area. Trash or Litter Paper, cans,bottles,totaling more than 1 cubic Area clear of litter. foot within a�andscaped area(trees and shrubs ! onty)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 Swface V4`ater Design 1�1anual - Appendix ,4 ]/24r?00� A-9 APPENDIX A MAINTENANCE REQUIREMENTS FLOW CONTROL,CONVEYANCE,AND VNQ FACILITIES NO. 24-CATCHBASIN INSERT Maintenance Defect or Problem Conditions When Maintenance is Needed Results Expected When Component Maintenance is Performed Catch Basin Inspection Inspection of inedia insert is required. Effluent water from media insert is free of als and has no visible sheen. Sediment When sediment forms a cap over the insert No sediment cap on the insert Accumulation media of the insert andlor unit. media and its unit. Trash and Debris Trash and debris accumulates on insert unit Trash and debris removed from Accumulation creating a blockage/restriction. insert unit. Runoff freely flows into catch basin. Media lnsert Water Saturated Catch basin insert is saturated with water,which Remove and replace media insert no longer has the capacity to absorb. Oil Saturated Media oil saturated due to petroleum spill that Remove and replace media insert. drains into catch basin. Service Life Exceeded Regular interval replacement due to typical Remove and replace media at average li(e of inedia insert product. regu�ar intervals,depending on insert product. , 1i24/200� ?005 Surface Water Design Manual Appendix r1 A-?(1