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HomeMy WebLinkAboutRS_Technical Information Report_171017_v2Markup Summary Subject: Text Box Page Label: 13 Lock: Unlocked Status: Checkmark: Unchecked Author: Ian Fitz-James Date: 10/16/2017 1:00:38 PM Color: Depth: include updated plans in report. Ian Fitz-James (5) Subject: Cloud+ Page Label: 16 Lock: Unlocked Status: Checkmark: Unchecked Author: Ian Fitz-James Date: 10/16/2017 1:50:17 PM Color: Depth: these numbers appear to be incorrect Subject: Cloud+ Page Label: 16 Lock: Unlocked Status: Checkmark: Unchecked Author: Ian Fitz-James Date: 10/16/2017 1:49:33 PM Color: Depth: these numbers are hard to follow / understand. suggest using a nomograph (figure 4.2.1.f of the 2017 rswdm) or providing an explanation of how you determined the inputs. Subject: Text Box Page Label: 17 Lock: Unlocked Status: Checkmark: Unchecked Author: Ian Fitz-James Date: 10/16/2017 1:38:13 PM Color: Depth: use rational method for less than 10 acres Subject: Cloud+ Page Label: 18 Lock: Unlocked Status: Checkmark: Unchecked Author: Ian Fitz-James Date: 10/16/2017 3:57:59 PM Color: Depth: this area needs to be included as part of the drainage basin draining to the new conveyance system. Know what's IN COMPLIANCE WITH CITY include updated plans in report. New PVC10Depth (y) (ft)0.410Culvert Radius r (ft)0.205Flow Angle (degrees)360.0Area (A) sq.ft.0.132Slope (S) ft/ft 0.0050n0.009 2r213249.1 SARnQ= these numbersappear to beincorrect New PVC10Depth (y) (ft)0.410Culvert Radius r (ft)0.205Flow Angle (degrees)360.0Area (A) sq.ft.0.132Slope (S) ft/ft 0.0050n0.009R^ 2/3 0.219Q (cfs)0.34Velocity2.563960546 (See Note Below) Note:Although the resulting velocity is less than the recommended 3 fps per the RSWDMStandards Section 4.2.1.1, CB's we placed closer for maintenance purposes asallowed by the RSWDM Standards (4.2.1.1). y 2r flow angle 213249.1 SARnQ= these numbers arehard to follow /understand. suggest using anomograph (figure4.2.1.f of the 2017rswdm) or providingan explanation ofhow you determinedthe inputs. use rational method for less than 10 acres SD SD SD SD SD SD SD SD SD SD SD SD SD this area needs to beincluded as part of thedrainage basin draining tothe new conveyance system. Abbreviated Technical Information Memorandum (For Repair and Maintenance) Vantage Glen Mobile Home Park 18100 107th Street S.E. Renton, Washington 98055 Parcel No. 322305-9361 Prepared for: King County Housing Authority Attn: Hugh Watkinson 600 Andover Park West Seattle, WA 98188-3326 September 29, 2017 Innova Architects Job No. 17-030 Prepared by: Jason Hein Reviewed by: Paul McCormick “I hereby state that this Abbreviated Technical Information Report for the Vantage Glen Mobile Home Park, Renton, Washington has been prepared by me or under my supervision and meets the standard of care and expertise which is usual and customary in this community for professional engineers. I understand that the City of Renton does not and will not assume liability for the sufficiency, suitability, or performance of drainage facilities prepared by me.” 09/29/ 2 0 1 7 2 Section 1 – Project Description The proponent, King County Housing Authority (KCHA), wishes to provide maintenance and repair to their existing drainage system located on Parcel No.322305-9361. We expect that the scope of work falls within guidelines of maintenance and repair. This Abbreviated Technical Information Memorandum (For Repair and Maintenance) is submitted with the Civil Construction Permit plan package, and is prepared to address the maintenance concerns that exist at the site. The project site is located at 104th Avenue SE, as shown on the Site Map (Exhibit 1), which follows. The site is located within the Vantage Glen development at 18100 107th Place S.E in Renton, Washington. The proposed work scope is limited to connecting roof drains at Lots 111, 112, 113, 114, 115 and 116 to the existing storm system, and installing two catchbasins and 10- inch storm line on the east side of 104th Avenue SE, near the point of tangent of the cul-de-sac. This work is proposed to address ponding on Lots 111, 112, 113, 114, 115 and 116 and on 104th Avenue SE near Lot 111, as shown on the photographs provided as Exhibits 2, 3 and 4. The original design intent was for lot drainage to flow to the eastern curb line of 104th Avenue SE. Cul-de-sac drainage was intended to flow to the south along the eastern curb line to a Type 1 catchbasin that conveys drainage to a detention pond, as shown in Exhibit 5. However, grading in the asbuilt condition allows drainage to pond at the cul-de-sac near Lot 111, and roof drainage at Lots 111, 112, 113, 114, 115, and 116 pond in the yards. The work proposed is intended to repair the existing ponding condition. Section 2 – Existing Site Conditions As noted in the section above, there is ponding in the yards of Lots 111, 112, 113, 114, 115 and 116, primarily due to roof drainage and low points in the lot yards. Downspouts at these lots are not tight-lined, and drainage flows from the downspouts to low points within the yards. There is a low point in the cul-de-sac at 104th Avenue SE, near the point of tangent at the eastern curb line, causing ponding, as shown in the site photographs, provided as Exhibits 2, 3 and 4. The original design plans show that the drainage intent was for cul-de-sac drainage to flow to the south at 1-percent, and to the east at 0.5-percent slope to the curb line. 104th Avenue SE is a super elevated road section, sloping from the west to the east. Lot drainage, per the original design, was intended to slope to the roadway curb line. Section 3 – Adjacent Areas The site is located between 105th Pl SE to the east and Wells Avenue S to the west, as shown on the Site Plan provided as Exhibit 1. The entrance to the development, Vantage Glen, is via SE 180th Street, which is west of the intersection of SE 180th Street and Highway 515. Section 4 – Proposed Solution This project proposes only maintenance and repair work. No new impervious or pervious areas are proposed. Work is limited to utility trenching and installation of 226 lineal feet of 10-inch storm line on the south side of 104th Avenue SE cul-de-sac, in order to alleviated ponding in the roadway. Work also includes the installation of 378 lineal feet of 6-inch roof drain and cleanouts to tight-line roof drainage to alleviate ponding in the yards at Lots 111, 112, 113, 114, 115 and 3 116. The proposed 10-inch storm line in the roadway (104th Avenue SE) will connect to an existing Type 1 catchbasin. This existing catchbasin has a 12-inch perforated outlet pipe that conveys drainage to the south to an existing detention pond. Roof drainage from Lots 111, 112, 113, 114, 115 and 116 is proposed to be tight-lined and connected to the new 10-inch storm line and to an existing 8-inch storm line, which is located along the eastern side of Lots 114, 115, and 116, as shown on Exhibit 6. Storm line trenching in the roadway (104th Avenue SE) results in 1,780 square feet of asphalt patching; and, utilities trenching for the roof drains in the lots results in 963 square feet of grass re-seeding. Proposed asphalt patching results in less than the 2,000 square foot threshold for replaced impervious surface, and the project results in less than the 7,000 square foot threshold of land disturbance. Also as noted above, drainage from the project site area drains to an existing detention pond, which was sized for the development (Vantage Glen), including drainage from the subject site area. The new 10-inch storm line was checked for capacity to flow the 100-year, 24-hour peak storm event. The 100-year peak was determined using a peak modeling program, StormShed. Printouts from Stormshed, including tributary basin area mapping follow. A simple capacity check of the 10-inch storm line was performed using the Manning Equation. These results also follow. 4 EXIBIT 1 SITE MAP 5 EXHIBIT 2 YARD PONDING AT LOTS 6 EXHIBIT 3 104TH AVENUE SE PONDING (EAST CURB LINE. LOOKING WEST) 7 EXHIBIT 4 104TH AVENUE SE PONDING (EAST CURB LINE, LOOKING NORTH) 8 EXHIBIT 5 ORIGINAL DESIGN PLANS – VANTAGE GLEN DEVELOPMENT 12 EXHIBIT 6 PROPOSED DESIGN PLANS SURFACE WATER STANDARD PLAN NOTES SURFACE WATER STANDARD PLAN NOTES 1.THESE NOTES SHALL APPEAR ON PROJECTS FOR THE SURFACE WATER UTILITY. 2.BEFORE ANY CONSTRUCTION OR DEVELOPMENT ACTIVITY OCCURS, A PRE-CONSTRUCTION MEETING MUST BE HELD BETWEEN THE CITY OF RENTON PLAN REVIEW SECTION AND THE APPLICANT. 3.ALL DESIGN AND CONSTRUCTION SHALL BE IN ACCORDANCE WITH THE RENTON MUNICIPAL CODE (RMC), THE LATEST EDITION OF THE STANDARD SPECIFICATION FOR ROAD, BRIDGE AND MUNICIPAL CONSTRUCTION PREPARED BY WSDOT AND THE AMERICAN PUBLIC WORKS ASSOCIATION (APWA) AS AMENDED BY THE CITY OF RENTON PUBLIC WORKS DEPARTMENT. IT SHALL BE THE SOLE RESPONSIBILITY OF THE APPLICANT AND THE PROFESSIONAL CIVIL ENGINEER TO CORRECT ANY ERROR, OMISSIONS OR VARIATION FROM THE ABOVE REQUIREMENTS FOUND IN THIS PLANS. ALL CORRECTIONS SHALL BE AT NO ADDITIONAL COST TO THE CITY. 4.APPROVAL OF THIS ROAD, GRADING, PARKING AND DRAINAGE PLAN DOES NOT CONSTITUTE AN APPROVAL OF ANY OTHER CONSTRUCTION (E.G. DOMESTIC WATER CONVEYANCE, SEWER CONVEYANCE, GAS, ELECTRIC, ETC.) THE SURFACE WATER DRAINAGE SYSTEM SHALL BE CONSTRUCTED ACCORDING TO THE APPROVED PLANS, WHICH ARE ON FILE IN WITH THE CITY. ANY DEVIATION FROM THE APPROVED PLANS WILL REQUIRE WRITTEN APPROVAL FROM THE CITY OF RENTON PUBLIC WORKS DEPARTMENT, SURFACE WATER UTILITY SECTION. 5.A COPY OF THESE APPROVED PLANS MUST BE ON THE JOB SITE WHENEVER CONSTRUCTION IS IN PROGRESS. 6.GRADING ACTIVITIES (SITE ALTERATION) ARE LIMITED TO THE HOURS OF 7 A.M. TO 7 P.M. MONDAY THROUGH SATURDAY AND NO WORK ON SUNDAY IS ALLOWED, UNLESS OTHERWISE APPROVED WITH A WRITTEN DECISION BY THE CITY OF RENTON. 7.,76+$//%(7+($33/,&$17¶6&2175$&725¶65(63216,%,/,7<722%7$,1$//&216758&7,21($6(0(1761(&(66$5< BEFORE INITIATING OFF-SITE WORK. EASEMENTS REQUIRE CITY REVIEW AND APPROVAL PRIOR TO CONSTRUCTION. 8.FRANCHISED UTILITIES OR OTHER INSTALLATIONS THAT ARE NOT SHOWN ON THESE APPROVED PLANS SHALL NOT BE CONSTRUCTED UNLESS AN APPROVED SET OF PLANS THAT MEET ALL REQUIREMENTS OF CHAPTER 4 OF THE SURFACE WATER DESIGN MANUAL ARE SUBMITTED TO THE CITY OF RENTON. 9.DATUM SHALL BE NAVD 88 UNLESS OTHERWISE APPROVED BY THE CITY OF RENTON. REFERENCE BENCHMARK AND ELEVATIONS ARE NOTED ON THE PLANS. 10.ANY DEWATERING SYSTEM NECESSARY FOR THE CONSTRUCTION OF STORMWATER FACILITIES MUST BE SUBMITTED TO THE CITY FOR REVIEW AND APPROVAL. 11.ALL UTILITY TRENCHES AND ROADWAY SUBGRADE SHALL BE BACKFILLED AND COMPACTED TO 95 PERCENT DENSITY, STANDARD PROCTOR. 12.OPEN CUTTING OF EXISTING ROADWAYS FOR NON-FRANCHISED UTILITY OR STORM DRAINAGE WORK IS NOT ALLOWED UNLESS SPECIFICALLY APPROVED BY THE CITY OF RENTON AND NOTED ON THESE APPROVED PLANS. ANY OPEN CUT SHALL BE RESTORED IN ACCORDANCE WITH THE CITY OF RENTON TRENCH RESTORATION STANDARDS. 13.ALL SEDIMENTATION/EROSION FACILITIES MUST BE IN OPERATION PRIOR TO CLEARING AND BUILDING CONSTRUCTION, AND THEY MUST BE SATISFACTORILY MAINTAINED UNTIL CONSTRUCTION IS COMPLETED AND THE POTENTIAL FOR ON-SITE EROSION HAS PASSED. 14.ALL RETENTION/DETENTION FACILITIES MUST BE INSTALLED AND IN OPERATION PRIOR TO OR IN CONJUNCTION WITH ALL CONSTRUCTION ACTIVITY UNLESS OTHERWISE APPROVED BY THE PUBLIC WORKS DEPARTMENT, SURFACE WATER UTILITY SECTION. 15.ALL PIPE AND APPURTENANCES SHALL BE LAID ON A PROPERLY PREPARED FOUNDATION IN ACCORDANCE WITH THE CURRENT STATE OF WASHINGTON STANDARD SPECIFICATION FOR ROAD AND BRIDGE CONSTRUCTION. THIS SHALL INCLUDE NECESSARY LEVELING OF THE TRENCH BOTTOM OR THE TOP OF THE FOUNDATION MATERIAL, AS WELL AS PLACEMENT AND COMPACTION OF REQUIRED BEDDING MATERIAL, TO UNIFORM GRADE SO THAT THE ENTIRE LENGTH OF THE PIPE WILL BE 6833257('21$81,)250/<'(16(81<,(/',1*%$6($//3,3(%('',1*6+$//%($3:$&/$66³&´:,7+7+( EXCEPTION OF PVC PIPE. 16.STEEL PIPE SHALL BE ALUMINIZED, OR GALVANIZED WITH ASPHALT TREATMENT #1 OR BETTER INSIDE AND OUTSIDE. 17.ALL DRAINAGE STRUCTURES, SUCH AS CATCH BASINS AND MANHOLES SHALL HAVE SOLID LOCKING LIDS. ALL DRAINAGE STRUCTURES ASSOCIATED WITH A PERMANENT RETENTION/DETENTION FACILITY SHALL HAVE SOLID LOCKING LIDS. 18.BUILDING AND OTHER STRUCTURES SHALL BE PLACED IN ACCORDANCE WITH TABLE 4.1 EASEMENT WIDTHS AND BUILDING SETBACKS LINES. 19.ALL CATCH BASIN GRATES SHALL BE DEPRESSED 0.10 FEET BELOW PAVEMENT LEVEL. 20.ALL DRIVEWAY CULVERTS LOCATED WITHIN CITY OF RENTON RIGHT-OF-WAY SHALL BE OF SUFFICIENT LENGTH TO PROVIDE A MINIMUM 3:1 SLOPE FROM THE EDGE OF THE DRIVEWAY TO THE BOTTOM OF THE DITCH. ROCK FOR EROSION PROTECTION OF ROADSIDE DITCHES, WHERE REQUIRED, SHALL BE OF SOUND QUARRY ROCK PLACED TO A DEPTH OF ONE (1) FOOT AND MUST MEET THE FOLLOWING SPECIFICATIONS: 4 - 8 INCH ROCK / 40 - 70% PASSING; 2 - 4 INCH ROCK / 30 - 40% PASSING; AND LESS THAN 2 INCH ROCK / 10 - 20% PASSING. 21.ALL BUILDING DOWNSPOUTS AND FOOTING DRAINS SHALL BE CONNECTED TO THE STORM DRAINAGE SYSTEM, UNLESS APPROVED BY THE CITY PLAN REVIEWER OR SURFACE WATER UTILITY SECTION. AN ACCURATELY DIMENSIONED, CERTIFIED AS-BUILT DRAWING OF THIS DRAINAGE SYSTEM WILL BE SUBMITTED TO THE CITY UPON COMPLETION. 22.DRAINAGE OUTLETS (STUB-OUTS) SHALL BE PROVIDED FOR EACH INDIVIDUAL LOT, EXCEPT FOR THOSE LOTS APPROVED FOR INFILTRATION BY THE CITY. STUB-OUTS SHALL CONFORM TO THE FOLLOWING: A. EACH OUTLET SHALL BE SUITABLY LOCATED AT THE LOWEST ELEVATION ON THE LOT, SO AS TO SERVICE ALL FUTURE ROOF DOWNSPOUTS AND FOOTING DRAINS, DRIVEWAYS, YARD DRAINS, AND ANY OTHER SURFACE OR SUBSURFACE DRAINS NECESSARY TO RENDER THE LOTS SUITABLE FOR THEIR INTENDED USE. EACH OUTLET SHALL HAVE FREE-FLOWING, POSITIVE DRAINAGE TO AN APPROVED STORMWATER CONVEYANCE SYSTEM OR TO AN APPROVED OUTFALL LOCATION. B. OUTLETS ON EACH LOT SHALL BE LOCATED WITH A FIVE-FOOT-HIGH, 2" X 4" STAKE MARKED "STORM" OR "DRAIN". THE STUB-OUT SHALL EXTEND ABOVE SURFACE LEVEL, BE VISIBLE, AND BE SECURED TO THE STAKE. C. PIPE MATERIAL SHALL CONFORM TO UNDERDRAIN SPECIFICATIONS DESCRIBED IN CHAPTER 4 OF THE SURFACE WATER DESIGN MANUAL AND, IF NON-METALLIC, THE PIPE SHALL BE PLACED IN A TRENCH WITH A TRACING WIRE ABOVE OR OTHER ACCEPTABLE DETECTION. D. PRIVATE DRAINAGE EASEMENTS ARE REQUIRED FOR DRAINAGE SYSTEMS DESIGNED TO CONVEY FLOWS THROUGH INDIVIDUAL LOTS. E. THE APPLICANT/CONTRACTOR IS RESPONSIBLE FOR COORDINATING THE LOCATIONS OF ALL STUBOUT CONVEYANCE LINES WITH RESPECT TO OTHER UTILITIES (E.G. POWER, GAS, TELEPHONE, TELEVISION). F. ALL INDIVIDUAL STUB-OUTS SHALL BE PRIVATELY OWNED AND MAINTAINED BY THE LOT HOME OWNER. G. STORM DRAINAGE PIPE SYSTEMS SHALL NOT PENETRATE BUILDING FOUNDATIONS, EXCEPT FOR SUMP PUMP DISCHARGE LINES USED TO DRAIN CRAWL SPACES, PROVIDED THE SUMP PUMP SYSTEM INCLUDES BACKFLOW PREVENTION OR A CHECK VALVE. 23.ALL DISTURBED PERVIOUS AREAS (COMPACTED, GRADED, LANDSCAPED, ETC.) OF THE DEVELOPMENT SITE MUST DEMONSTRATE ONE OF THE FOLLOWING: THE EXISTING DUFF LAYER SHALL BE STAGED AND REDISTRIBUTED TO MAINTAIN THE MOISTURE CAPACITY OF THE SOIL, OR; AMENDED SOIL SHALL BE ADDED TO MAINTAIN THE MOISTURE CAPACITY. 24.PROOF OF LIABILITY INSURANCE SHALL BE SUBMITTED TO THE CITY PRIOR TO CONSTRUCTION PERMIT ISSUANCE. 25.ISSUANCE OF THE BUILDING OR CONSTRUCTION PERMITS BY THE CITY OF RENTON DOES NOT RELIEVE THE OWNER OF THE CONTINUING LEGAL OBLIGATION AND/OR LIABILITY CONNECTED WITH STORM SURFACE WATER DISPOSITION. FURTHER, THE CITY OF RENTON DOES NOT ACCEPT ANY OBLIGATION FOR THE PROPER FUNCTIONING AND MAINTENANCE OF THE SYSTEM PROVIDED DURING CONSTRUCTION. 26.THE CONTRACTOR SHALL BE RESPONSIBLE FOR PROVIDING ADEQUATE SAFEGUARD, SAFETY DEVICES, PROTECTIVE EQUIPMENT,FLAGGERS, AND ANY OTHER NEEDED ACTIONS TO PROTECT THE LIFE, HEALTH, AND SAFETY OF THE PUBLIC, AND TO PROTECT PROPERTY IN CONNECTION WITH THE PERFORMANCE OF WORK. ANY WORK WITHIN THE TRAVELED RIGHT-OF-WAY THAT MAY INTERRUPT NORMAL TRAFFIC FLOW SHALL REQUIRE A TRAFFIC CONTROL PLAN APPROVE BY THE PUBLIC WORKS DEPARTMENT, TRANSPORTATION SYSTEMS DIVISION. ALL SECTIONS OF THE WSDOT STANDARD SPECIFICATIONS 1-07-23 TRAFFIC CONTROL SHALL APPLY. 27.PROJECT LOCATED WITHIN THE AQUIFER PROTECTION AREA (APA) SHALL COMPLY WITH SPECIAL REQUIREMENT #6 OF THE SURFACE WATER DESIGN MANUAL AND AQUIFER PROTECTION REGULATIONS (RMC 4-3-050). EROSION CONTROL NOTES 1.THESE NOTES SHALL APPEAR FOR ALL PROJECTS - SITE IMPROVEMENTS, SURFACE WATER UTILITY, WASTEWATER UTILITY, WATER UTILITY, AND TRANSPORTATION PLANS: 2.BEFORE ANY CONSTRUCTION OR DEVELOPMENT ACTIVITY OCCURS, A PRE-CONSTRUCTION MEETING MUST BE HELD WITH THE CITY OF RENTON, PUBLIC WORKS DESIGN ENGINEER. 3.THE BOUNDARIES OF THE CLEARING LIMITS AND AREAS OF VEGETATION PRESERVATION AS PRESCRIBED ON THE PLAN(S) SHALL BE CLEARLY FLAGGED BY SURVEY TAPE OR FENCING IN THE FIELD PRIOR TO CONSTRUCTION IN ACCORDANCE WITH APPENDIX D OF THE SURFACE WATER DESIGN MANUAL AND OBSERVED DURING CONSTRUCTION. DURING THE CONSTRUCTION PERIOD, NO DISTURBANCE BEYOND THE CLEARING LIMITS SHALL BE PERMITTED. THE CLEARING LIMITS SHALL BE MAINTAINED BY THE APPLICANT/ESC SUPERVISOR FOR THE DURATION OF CONSTRUCTION. 4.STABILIZED CONSTRUCTION ENTRANCES SHALL BE INSTALLED AT THE BEGINNING OF CONSTRUCTION AND MAINTAINED FOR THE DURATION OF THE PROJECT. ADDITIONAL MEASURES, SUCH AS CONSTRUCTED WHEEL WASH SYSTEMS OR WASH PADS, MAY BE REQUIRED TO ENSURE THAT ALL PAVED AREAS ARE KEPT CLEAN AND TRACK OUT TO ROAD RIGHT OF WAY DOES NOT OCCUR FOR THE DURATION OF THE PROJECT. 5.ALL REQUIRED SEDIMENTATION/EROSION CONTROL FACILITIES MUST BE CONSTRUCTED AND IN OPERATION PRIOR TO LAND CLEARING AND/OR CONSTRUCTION TO PREVENT TRANSPORTATION OF SEDIMENT TO SURFACE WATER, DRAINAGE SYSTEMS AND ADJACENT PROPERTIES. ALL EROSION AND SEDIMENT FACILITIES SHALL BE MAINTAINED IN A SATISFACTORY CONDITION UNTIL SUCH TIME THAT CLEARING AND/OR CONSTRUCTION IS COMPLETE AND POTENTIAL FOR ON-SITE EROSION HAS PASSED. THE IMPLEMENTATION, MAINTENANCE, REPLACEMENT AND ADDITIONS TO EROSION/SEDIMENTATION CONTROL SYSTEMS SHALL BE THE RESPONSIBILITY OF THE PERMITEE. 6.THE EROSION AND SEDIMENTATION CONTROL SYSTEMS DEPICTED ON THIS DRAWING ARE INTENDED TO BE MINIMUM REQUIREMENTS TO MEET ANTICIPATED SITE CONDITIONS. AS CONSTRUCTION PROGRESSES AND UNEXPECTED OR SEASONAL CONDITIONS DICTATE, THE PERMITEE SHALL ANTICIPATE THAT MORE EROSION AND SEDIMENTATION CONTROL FACILITIES WILL BE NECESSARY TO ENSURE COMPLETE SILTATION CONTROL ON THE PROPOSED SITE. DURING THE COURSE OF CONSTRUCTION, IT SHALL BE THE OBLIGATION AND RESPONSIBILITY OF THE PERMITEE TO ADDRESS ANY NEW CONDITIONS THAT MAY BE CREATED BY THE ACTIVITIES AND TO PROVIDE ADDITIONAL FACILITIES, OVER AND ABOVE MINIMUM REQUIREMENTS, AS MAY BE NEEDED, TO PROTECT ADJACENT PROPERTIES AND WATER QUALITY OF THE RECEIVING DRAINAGE SYSTEM. 7.APPROVAL OF THIS PLAN IS FOR EROSION/SEDIMENTATION CONTROL ONLY. IT DOES NOT CONSTITUTE AN APPROVAL OF STORM DRAINAGE DESIGN, SIZE NOR LOCATION OF PIPES, RESTRICTORS, CHANNELS, OR RETENTION FACILITIES. 8.ANY AREAS OF EXPOSED SOILS, INCLUDING ROADWAY EMBANKMENTS, THAT WILL NOT BE DISTURBED FOR TWO DAYS DURING THE WET SEASON (OCTOBER 1 ST TROUGH MARCH 30TH) OR SEVEN DAYS DURING THE DRY SEASON (APRIL 1ST TOUGH SEPTEMBER 30TH) SHALL BE IMMEDIATELY STABILIZED WITH THE APPROVED ESC COVER METHODS (E.G., SEEDING, MULCHING, PLASTIC COVERING, ETC.). 9.WET SEASON SEASONAL EROSION AND SEDIMENT CONTROL REQUIREMENTS APPLY TO ALL CONSTRUCTION SITES CLEARING BETWEEN OCTOBER 1 ST AND MARCH 30TH INCLUSIVE, UNLESS OTHERWISE APPROVED BY THE CITY THROUGH AN ADJUSTMENT PROCESS. 10.COVER MEASURES WILL BE APPLIED IN CONFORMANCE WITH APPENDIX D OF THE SURFACE WATER DESIGN MANUAL. 11.ANY AREA NEEDING ESC MEASURES, NOT REQUIRING IMMEDIATE ATTENTION, SHALL BE ADDRESSED WITHIN SEVEN (7) DAYS. 12.THE ESC FACILITIES ON INACTIVE SITES SHALL BE INSPECTED AND MAINTAINED A MINIMUM OF ONCE A MONTH OR WITHIN 24 HOURS FOLLOWING A STORM EVENT. 13.AT NO TIME SHALL MORE THAN ONE (1) FOOT OF SEDIMENT BE ALLOWED TO ACCUMULATE WITHIN A CATCH BASIN. ALL CATCH BASINS AND CONVEYANCE LINES SHALL BE CLEANED PRIOR TO PAVING. THE CLEANING OPERATION SHALL NOT FLUSH SEDIMENT-LADEN WATER INTO THE DOWNSTREAM SYSTEM. 14.DURING THE TIME PERIOD OF OCTOBER 1 ST THROUGH MARCH 30TH, ALL PROJECT DISTRIBUTED SOIL AREAS GREATER, THAT ARE TO BE LEFT UN-WORKED FOR MORE THAN 12 HOURS, SHALL BE COVERED BY MULCH, SODDING OR PLASTIC COVERING. 15.ANY PERMANENT RETENTION/DETENTION FACILITY USED AS A TEMPORARY SETTLING BASIN SHALL BE MODIFIED WITH THE NECESSARY EROSION CONTROL MEASURES AND SHALL PROVIDE ADEQUATE STORAGE CAPACITY. IF THE PERMANENT FACILITY IS TO FUNCTION ULTIMATELY AS AN INFILTRATION SYSTEM, THE TEMPORARY FACILITY MUST BE ROUGH GRADED SO THAT THE BOTTOM AND SIDES ARE AT LEAST THREE FEET ABOVE THE FINAL GRADE OF THE PERMANENT FACILITY. 16.PRIOR TO THE BEGINNING OF THE WET SEASON (OCT. 1), ALL DISTURBED AREAS SHALL BE REVIEWED TO IDENTIFY WHICH ONES CAN BE SEEDED IN PREPARATION FOR THE WINTER RAINS. DISTURBED AREAS SHALL BE SEEDED WITHIN ONE WEEK OF THE BEGINNING OF THE WET SEASON.A SKETCH MAP OF THOSE AREAS TO BE SEEDED AND THOSE AREAS TO REMAIN UNCOVERED SHALL BE SUBMITTED TO THE CITY OF RENTON FOR REVIEW. 17.ALL ESC MEASURES MUST BE REMOVED AFTER CONSTRUCTION ACTIVITY IS COMPLETE.HIGHWAY 167108TH AVE SE176TH STREET S CA R R R O A D VICINITY MAP SITE PROJECT LOCATION CONTACTS DEVELOPER KING COUNTY HOUSING AUTHORITY HUGH WATKINSON CAPITAL CONSTRUCTION PROJECT MANAGER 600 ANDOVER PARK WEST SEATTLE, WA 98188 SURVEYOR TRIAD GREGORY T. JUNEAU, PLS 20300 WOODINVILLE SNOHOMISH ROAD NE, SUITE A WOODINVILLE, WA 98072 PH 425-415-2041 CIVIL ENGINEER INNOVA ARCHITECTS PAUL MCCORMIK, PE 950 PACIFIC AVENUE, SUITE 450 TACOMA, WA 98402 PH 253-572-4903 UTILITIES WATER - SOOS CREEK WATER AND SEWER DISTRICT SEWER - SOOS CREEK WATER AND SEWER DISTRICT STORM - CITY OF RENTON TELEPHONE - QWEST / CENTURY LINK POWER - PUGET SOUND ENERGY NAT GAS - PUGET SOUND ENERGY A PORTION OF THE SW 1/4 OF THE NE 1/4 OF SECTION 32, TOWNSHIP 23, RANGE 5 E., W.M. CITY OF RENTON, KING COUNTY, WASHINGTON KING COUNTY HOUSING AUTHORITY-VANTAGE GLEN MOBILE HOME PARK Know what's R SITE DETAILS ADDRESS:18102 107TH PL SE, RENTON, WA PARCEL:322305-9361 ZONING:RESIDENTIAL MANUFACTURED HOMES GROSS SITE AREA:“6) “$&5(6 PROJECT SITE AREA:“6) “$&5(6 AUTOCAD FILE AUTOCAD DRAWING FILES ARE AVAILABLE FOR SITE LAYOUT UPON REQUEST. GENERAL NOTES TAKEN FROM SURVEY 1.) BOUNDARY LINES SHOWN ARE BASED ON RENTON SHORT PLAT #LUA-08-137-SHPL RECORDED IN VOLUME 268 OF SURVEYS, PAGES 168-170, IN KING COUNTY, WASHINGTON. 2.) INSTRUMENTATION FOR THIS SURVEY WAS A TRIMBLE VX SPATIAL STATION. PROCEDURES USED IN THIS SURVEY WERE FIELD TRAVERSE, MEETING OR EXCEEDING STANDARDS SET BY WAC 332-130-090. 3.) THE INFORMATION DEPICTED ON THIS MAP REPRESENTS THE RESULTS OF A SURVEY MADE IN MAY 2017 AND CAN ONLY BE CONSIDERED AS INDICATING THE GENERAL CONDITION EXISTING AT THAT TIME. 4.) SANITARY SEWER AND STORM DRAINAGE FACILITIES HAVE BEEN ASBUILT THROUGH FIELD MEASUREMENTS OF THE LOCATION OF THE ACCESS STRUCTURES, THE TOP ELEVATION OF THE STRUCTURES, AND THE INVERT ELEVATIONS OF ANY PIPES ENTERING OR LEAVING THE STRUCTURES. IT IS STANDARD PRACTICE TO SHOW THE PIPES CONNECTING THESE STRUCTURES AS STRAIGHT LINES. THIS IS ONLY AN ASSUMPTION AND THE ACTUAL LOCATION OF THE PIPING MUST BE VERIFIED IN THE FIELD BY THE CONTRACTOR PRIOR TO ANY CONSTRUCTION. 5.) NO EASEMENTS, RESTRICTIONS OR RESERVATION OF RECORD WHICH WOULD BE DISCLOSED BY TITLE REPORT ARE SHOWN. 6.) PIPE ELEVATIONS SHOWN FOR INACCESSIBLE YARD DRAIN STRUCTURES ARE APPROXIMATE TO THE TENTH OF A FOOT AND SHOULD BE FIELD VERIFIED PRIOR TO ANY CONSTRUCTION ACTIVITY AS NECESSARY. BASIS OF BEARING RENTON SHORT PLAT #LUA-08-137-SHPL RECORDED IN VOLUME 268 OF SURVEYS, PAGES 168-170, IN KING COUNTY, WASHINGTON LEGAL DESCRIPTION LOT 2 AND TRACT C-2 OF RENTON SHORT PLAT #LUA-08-137-SHPL RECORDED IN VOLUME 268 OF SURVEYS, PAGES 168-170, IN KING COUNTY, WASHINGTON HORIZONTAL DATUM NAD83/91 - WASHINGTON NORTH ZONE BASED ON TIES TO CITY OF RENTON CONTROL POINTS NOS. 1866 AND 2110 VERTICAL DATUM NAVD 88 BENCH MARK ORIGINAL BENCHMARK: CITY OF RENTON BENCH MARK NO. 2139 TOP OF 3" BRASS DISC SET IN DRILL HOLE OF LUMINARY STAMPED "KING &2817<.&)$“ ($672)ȭ 108TH AVE NE AT THE INTERSECTION :,7+6(3(7529,76.<5'$1'“ :(672)%8,/',1* ELEVATION = 400.99 (NOT SHOWN HEREON) TBM "A" TOP OF CHISELED SQUARE AT THE NORTHWEST CORNER OF THE WEST END 2)&21&5(7(6,'(:$/.217+(6287+6,'(2)6(7+67%(,1*“ :(672)7+(,17(56(&7,212)6(7+67$1'7+$9(6($1'“ WEST OF CENTERLINE CROSSWALK TO FRED MEYER SHOPPING CENTER. ELEVATION = 384.73 (NOT SHOWN HEREON) TBM "B" TOP OF RAIL ROAD SPIKE SET IN WEST FACE POWER POLE 1.2' ABOVE GRADE ON THE EAST SIDE OF 105TH PL SE LOCATED AT THE APPROXIMATE EXTENSION OF THE NORTH PROPERTY LINE. ELEVATION = 380.33 (NOT SHOWN HEREON) CIVIL SHEET INDEX SHEET NO SHEET TITLE C1.0 COVER SHEET C1.1 DRAINAGE PLAN AND PROFILE C1.2 DETAILS CONSTRUCTION SEQUENCE 1.CONTRACTOR TO ARRANGE AND ATTEND PRE-CONSTRUCTION MEETING. 2.POST SIGN WITH NAME AND PHONE NUMBER OF CSWPP/ESC SUPERVISOR (MAY BE CONSOLIDATED WITH THE REQUIRED NOTICE OF CONSTRUCTION SIGN. 3.FLAG OR FENCE CLEARING LIMITS. 4.INSTALL CATCH BASIN PROTECTION AND STORMWATER BMP AREA PROTECTION AS SHOWN ON PLANS. 5.INSTALL SILT FENCE AS SHOWN ON PLANS. 6.MAINTAIN EROSION CONTROL MEASURES IN ACCORDANCE WITH APPENDIX D OF THE CITY OF RENTON SURFACE WATER DESIGN MANUAL AND MANUFACTURE'S RECOMMENDATIONS. 7.RELOCATE EROSION CONTROL MEASURES OR INSTALL NEW MEASURES SO THAT AS SITE CONDITIONS CHANGE THE EROSION AND SEDIMENT CONTROL AND POLLUTION PREVENTION IS ALWAYS IN ACCORDANCE WITH THE CITY'S EROSION AND SEDIMENT CONTROL STANDARDS. 8.COVER ALL AREAS THAT WILL BE UNWORKED FOR MORE THAN SEVEN DAYS DURING THE DRY SEASON OR TWO DAYS DURING THE WET SEASON WITH STRAW, WOOD FIBER MULCH, COMPOST, OR EQUIVALENT. 9.STABILIZE ALL AREAS THAT REACH FINAL GRADE WITHIN SEVEN DAYS. 10.SEED OR SOD ANY AREAS TO REMAIN UNWORKED FOR MORE THAN 30 DAYS. 11.CONSTRUCT STORM LINE AS SHOWN ON PLAN. PROVIDE PAVEMENT PATCHING/RESTORATION AS SHOWN ON PLANS. 12.UPON COMPLETION OF THE PROJECT, ALL DISTURBER AREAS MUST BE STABILIZED AND BMP'S REMOVED. IN COMPLIANCE WITH CITY OF RENTON STANDARDS 24Ä4Ä8#06#)').'05614/&4#+0':6'05+10%Ä.7#1(8#06#)').'05614/&4#+0':6'05+105614/5;56'/':6'05+10 8#06#)').'0/1$+.'*1/'2#4- -+0)%1706;*175+0)#76*14+6;6'&ÄÄWET SEASON SPECIAL PROVISIONS 1.THE ALLOWED TIME THAT A DISTURBED AREA MAY REMAIN UNWORKED WITHOUT COVER MEASURES IS REDUCED TO TWO CONSECUTIVE WORKING DAYS, RATHER THAN SEVEN (SECTION D.2.1.2). 2.STOCKPILES AND STEEP CUT AND FILL SLOPES ARE TO BE PROTECTED IF UNWORKED FOR MORE THAN 12 HOURS (SECTION D.2.1.2). 3.COVER MATERIALS SUFFICIENT TO COVER ALL DISTURBED AREAS SHALL BE STOCKPILED ON SITE (SECTION D.2.1.2). 4.ALL AREAS THAT ARE TO BE UNWORKED DURING THE WET SEASON SHALL BE SEEDED WITHIN ONE WEEK OF THE BEGINNING OF THE WET SEASON (SECTION D.2.1.2.6). 5.MULCH IS REQUIRED TO PROTECT ALL SEEDED AREAS (SECTION D.2.1.2.2). 6.FIFTY LINEAR FEET OF SILT FENCE (AND THE NECESSARY STAKES) PER ACRE OF DISTURBANCE MUST BE STOCKPILED ON SITE (SECTION D.2.1.3.1). 7.CONSTRUCTION ROAD AND PARKING LOT STABILIZATION ARE REQUIRED FOR ALL SITES UNLESS THE SITE IS UNDERLAIN BY COARSE-GRAINED SOIL (SECTION D.2.1.4.2). 8.SEDIMENT RETENTION IS REQUIRED UNLESS NO OFFSITE DISCHARGE IS ANTICIPATED FOR THE SPECIFIED DESIGN FLOW (SECTION D.2.1.5). 9.SURFACE WATER CONTROLS ARE REQUIRED UNLESS NO OFFSITE DISCHARGE IS ANTICIPATED FOR THE SPECIFIED DESIGN FLOW (SECTION D.2.1.6). 10.PHASING AND MORE CONSERVATIVE BMPS MUST BE EVALUATED FOR CONSTRUCTION ACTIVITY NEAR SURFACE WATERS (SECTION D.2.4.3). 11.ANY RUNOFF GENERATED BY DEWATERING MAY BE REQUIRED TO DISCHARGE TO THE SANITARY SEWER (WITH APPROPRIATE DISCHARGE AUTHORIZATION), PORTABLE SAND FILTER SYSTEMS, OR HOLDING TANKS (SECTION D.2.2).P:\2017\17-030 KCHA Vantage Glen MHP\CAD\CIVIL\17-030_C.dwg, 9/29/2017 1:17:12 PM, jhein09/29/2 0 1 7 include updated plans in report. SD SD SD SD SD SD SD SD SD SD SD SD EXISTING SURFACE Know what's R A PORTION OF THE SW 1/4 OF THE NE 1/4 OF SECTION 32, TOWNSHIP 23, RANGE 5 E., W.M. CITY OF RENTON, KING COUNTY, WASHINGTON KING COUNTY HOUSING AUTHORITY-VANTAGE GLEN MOBILE HOME PARK KEY NOTES: 1 REMOVE DEBRIS FROM EXISTING CATCH BASIN OR YARD DRAIN. SEE GENERAL NOTE 13. 2 PRIOR TO ANY CONSTRUCTION OR ORDERING OF MATERIALS CLEAN EXISTING STORM DRAIN PIPE. CONFIRM CONDITION AND SERVICEABILITY OF EXISTING STORMDRAIN. CONFIRM POSITIVE PIPE SLOPE FROM EXISTING CB #12027 TO NEW 10" STORMDRAIN. REPLACE PIPE IF DAMAGED OR POSITIVE SLOPE CANNOT BE ACHIEVED. 3 PROVIDE NEAT LINE SAWCUT AND PAVEMENT PATCH HOT TAR AND SEAL JOINT. 4 RECONSTRUCT IN-KIND CONCRETE ROLLED CURB AND GUTTER. 5 CONNECT NEW 10" STORM DRAIN TO EXISTING CATCH BASIN. SEE GENERAL NOTES. 6 PROTECT EXISTING UTILITIES AND STRUCTURES. RESTORE ANY DISTURBED AREA IN-KIND. 7 CONNECT EXISTING YARD DRAINS TO NEW 10" STORM LINE WITH WYE CONNECTION. 8 POTHOLE AND LOCATE EXISTING 8" STORM LINE. CONNECT DOWNSPOUTS TO EXISTING 8" STORM. 9 CONNECT EXISTING ROOF DRAIN DOWN SPOUT TO NEW 6" ROOF DRAIN AND PROVIDE CLEANOUT. 10 PROVIDE INLET PROTECTION. SEE DETAIL 11 CONFIRM 6" CMP CONNECTION FROM YARD DRAIN TO EXISTING 12" STORM DRAIN. 12 PROTECT EXISTING RETAINING WALL 1 2 3 1 2 1 1 1 5 46 46 GENERAL NOTES: 1.CONNECT ROOF DOWN SPOUTS AS SHOWN ON PLAN. 2.PROVIDE CB TYPE 1 PER CITY OF RENTON STD. PLAN 200.00. 3.PROVIDE 6" PVC ROOF DRAIN PIPING PER WSDOT STD SPEC 9-05.1(5). PIPE SLOPE SHALL BE 0.5% MINIMUM. 4.PROVIDE 10" PVC SDR 35 PER WSDOT STD SPEC 9-05.12(1). 5.PROVIDE TOP SOIL AS REQURIED PER WSDOT STD SPEC 9-14. 6.PROVIDE ASPHALT PAVEMENT (HMA CL-1/2 PG 64-22) PER WSDOT STD SPEC 5-04. 7.PROVIDE CONCRETE ROLLED CURB IN-KIND CLASS 4000 PER WSDOT STD SPEC 5-05. 8.PROVIDE COMPACTION FOR ROCK BASE PER WSDOT STD SPEC 4-04.3(5). 9.PROVIDE VANED GRATE PER CITY OF RENTON STD. PLAN 204.20. 10.PROVIDE 6" STORM SEWER CLEAN OUT PER WSDOT STD PLAN B-85.40-00. 11.SEE SHEET C1.0 FOR EROSION CONTROL NOTES. 12.FIELD LOCATE DOWN SPOUTS (DS). CONNECT DOWN SPOUTS IDENTIFIED ON PLAN. PROVIDE CLEAN OUT AT DOWN SPOUT CONNECTION. 13.CONTACT ENGINEER IF THERE ARE DISCREPANCIES IN CONNECTING ROOF DRAINS AS SHOWN ON PLANS. 14.PROVIDE INLET PROTECTION PER DETAIL SHOWN ON SHEET 3 FOR THE NEXT STRUCTURE DOWNSTREAM OF THE CONNECTION POINT. 15.ALL STORM DRAINAGE INFRASTRUCTURE SHOWN ON THIS PLAN WILL BE PRIVATELY MAINTAINED BY VANTAGE GLEN MOBILE HOME PARK. 8 7 7 9 typ 10 10 IN COMPLIANCE WITH CITY OF RENTON STANDARDS 24Ä4Ä8#06#)').'05614/&4#+0':6'05+10%Ä.7#1(8#06#)').'05614/&4#+0':6'05+105614/5;56'/':6'05+10 8#06#)').'0/1$+.'*1/'2#4- -+0)%1706;*175+0)#76*14+6;6'&ÄÄ2 2 2 2 10 4 4 6 6 4 6 2 28 6 8 6 10 6 1 11 12 12 12 P:\2017\17-030 KCHA Vantage Glen MHP\CAD\CIVIL\17-030_C.dwg, 9/29/2017 1:18:07 PM, jhein09/29/201 7 Know what's R A PORTION OF THE SW 1/4 OF THE NE 1/4 OF SECTION 32, TOWNSHIP 23, RANGE 5 E., W.M. CITY OF RENTON, KING COUNTY, WASHINGTON KING COUNTY HOUSING AUTHORITY-VANTAGE GLEN MOBILE HOME PARK CATCH BASIN TYPE 11 CATCH BASIN INSTALLATION2 CATCH BASIN FILTER3 4 5PIPE COMPACTION DESIGN AND BACKFILL ASPHALT PATCH AND INTERFACE DETAIL IN COMPLIANCE WITH CITY OF RENTON STANDARDS 24Ä4Ä8#06#)').'05614/&4#+0':6'05+10%Ä.7#1(8#06#)').'05614/&4#+0':6'05+105614/5;56'/':6'05+10 8#06#)').'0/1$+.'*1/'2#4- -+0)%1706;*175+0)#76*14+6;6'&ÄÄ*SDR 35 PIPE SHALL BE USED IN PLACE OF CMP AND LCPE AS SHOWN ON DETAIL ABOVE. RECTANGULAR FRAME RECTANGULAR VANED GRATE7 RECTANGULAR SOLID METAL COVER8 9 SILT FENCE6 P:\2017\17-030 KCHA Vantage Glen MHP\CAD\CIVIL\17-030_C.dwg, 9/29/2017 1:19:38 PM, jhein09/29/ 2 0 1 7 9/29/2017 C:\Users\jhein\AppData\Local\Temp\Bluebeam Software83525098.xlsx 83525098.xlsx CULVERT SIZING New PVC 10 Depth (y) (ft)0.410 Culvert Radius r (ft)0.205 Flow Angle (degrees)360.0 Area (A) sq.ft.0.132 Slope (S) ft/ft 0.0050 n 0.009 R^2/3 0.219 Q (cfs)0.34 Velocity 2.563960546 (See Note Below) Note: Although the resulting velocity is less than the recommended 3 fps per the RSWDM Standards Section 4.2.1.1, CB's we placed closer for maintenance purposes as allowed by the RSWDM Standards (4.2.1.1). y 2r flow angle 2 1 3 249.1 SARnQ= these numbers are hard to follow / understand. suggest using a nomograph (figure 4.2.1.f of the 2017 rswdm) or providing an explanation of how you determined the inputs. these numbers appear to be incorrect use rational method for less than 10 acres SD SD SD SD SD SD SD SD SD SD SD SD SD P:\2017\17-030 KCHA Vantage Glen MHP\CAD\CIVIL\17-030_Areas.dwg, 9/28/2017 10:19:46 AM, jheinthis area needs to be included as part of the drainage basin draining to the new conveyance system.