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Home My WebLink AboutTED4003451.70 a w 2 x2" BY 14 Go. WIRE OR EQUIVALENT, IF STANDARD STRENGTH FABRIC USED FIL TER FABRIC MIN. 4"x4" TRENCH BACKFILL TRENCH WITH NATIVE SOIL OR 3 4 -1 WASHED GRAVEL AT POSTS. USE STAPLES, WIRE RINGS OR EQUIVALENT TO ATTACH FABRIC TO POSTS 2' MIN 112" MIN. POSTS CROSS SECTION POR OF THE NE 1/4 OF THE SE 1/4 & THE SE 1/4 OF THE NE 1/4, ALL IN SEC. 10, TWP. 23 N., RGE. 5 E., W.M. 2 x2" BY 14 Go. WIRE OR EQUIVALENT, IF STANDARD STRENGTH FABRIC USED .......■...■.........■..■..ra ..................■■■..■... owl .■ ........... III III ....om 11 1010 mom" mono MUM g2sot ......monsoon .ul �� `��•v'�'v'v'v �v v v �• i �v v v v v v�r� MAINTENANCE STANDARDS N07E FILTER FABRIC FENCES SHALL BE INSTALLED ALONG CONTOUR WHENEVER POSSIBLE. 1. ANY DAMAGE SHALL BE REPAIRED IMMEDIATELY. 2. IF CONCENTRATED FLOWS ARE EVIDENT UPHILL OF 774E FENCES, THEY MUST BE INTERCEPTED AND CONVEYED TO A SEDIMENT TRAP OR POND. J. IT IS IMPORTANT TO CHECK THE UPHILL SIDE OF THE FENCE FOR SIGNS OF THE FENCE CLOGGING AND AC77NG AS A BARRIER TO FLOW AND THEN CAUSING CHANNELIZATTON OF FLOWS PARALLEL TO THE FENCE. IF THIS OCCURS, REPLACE THE FENCE AND/OR REMOVE 774E TRAPPED SEDIMENT. 4. SEDIMENT MUST BE REMOVED WHEN 774E SEDIMENT IS 5" HIGH. 5. IF THE FILTER FABRIC HAS DETERIORATED DUE TO ULTRAVIOLET BREAKDOWN, IT SHALL BE REPLACED. 6. WHERE THE SILT FENCE BORDERS WE7LANDS AREAS, BRIGHT ORANGE FENCING (BEL TON INDUSTRIES STYLE 803, OR EQUIVALENT) SHALL BE USED. (FIGURE DAE OF THE 2005 KCSWDM) SILT FENCE DETAIL NOT TO SCALE R=25' MIN AS PER KING COUNTY ROAD STANDARDS, DRI VEWA YS SHALL BE PA VED TO 774E EDGE OF R-O-W PRIOR TO INSTALLATION OF THE CONSTRUCTION ENTRANCE TO AVOID DAMAGING OF THE ROADWAY. IT IS RECOMMENDED THAT THE ENTRANCE BE CROWNED SO THAT RUNOFF DRAINS ° OFF THE PAD. ° 0 INSTALL DRIVEWAY CULVERT 12" MIN. THICKNESS doh 1F THERE IS A ROADSIDE DITCH a A�� PRESENT, AS PER KING COUNTY 4"-8" QUARRY SPALLS P �5 PROVIDE FULL WID1N OF ROAD STANDARDS PLACE AT FUTURE SUBGRADE INGRESS/EGRESS AREA ELEVA 77ON IF POSSIBLE (FIGURE D. 4. G OF 774E 2005 KCSWDM) STABILIZED CONSTRUCTION ENTRANCE DETAIL NOT TO SCALE SWALE CROSS SECTION Q ROCK CHECK DAM DITCH SLOPE CHECK DAM SPACING 0 - 5X 150' 5 - 10X 100' >10X 50' 5' 1 12.0' SWALE MIN. 0.25' NOTE' ROCK SHALL BE 4" MINUS QUARRY ROCK. CLEANED WHEN COLLECTED DEBRIS EXCEEDS 1/2 OF ITS DEPTH. ROCK CHECK DAM CROSS SECTION INTERCEPTOR SWALE AND ROCK CHECK DAM DETAILS NOT TO SCALE 1 RIP -RAP SHALL BE IN ACCORDANCE WITH SEC7701V 9-13.1 OF 7HE W.S.D.0.T.IA. P.W.A. STANDARD SPECInCA770NS RIP -RAP SHALL BE REASONABLY WELL GRADED W17H ROCK GRADA77ON AS FOLLOWS.• 100X PASSING 8-INC114 SQUARE SIEVE 4OX--60% PASSING 6-INCE SQUARE SIEVE 0-IOX PASSING 2-1NCE SQUARE SIEVE a frrL ruyur- rvo rz) 1. CLIP FENCE TO GAL V. WIRE 2. WIRE FENCE TO STEEL FENCE POST DO NOT ATTACH TO TREES OR 07HER NA77VE VEGETA77ON ORANGE CONSTRUCTION FENCE DETAIL NOT TO SCALE FIL ER FENCE N07ES 1. 774E FILTER FABRIC SHALL BE PURCHASED IN A CON77N000S ROLL CUT TO THE LENGTH OF 774E BARRIER TO AVOID USE OF JOINTS WHEN JOINTS ARE NECESSARY, FILTER CL07H SHALL BE SPLICED TOGETHER ONLY AT A SUPPORT POST WI774 A MINIMUM 6-INCH OVERLAP AND BOTH ENDS SECURELY FASTENED TO 174E POST. 2 THE FILTER FABRIC FENCE SHALL BE INSTALLED TO FOLLOW THE CONTOURS (WHERE FEASIBLE). THE FENCE POSTS SHALL BE SPACED AT A MAXIMUM OF 6 FEET APART AND DRIVEN SECURELY INTO 774E GROUND (MINIMUM OF 30 INCHES). J. A TRENCH SHALL BE EXCAVATED, ROUGHLY 8 INCHES WIDE AND 12 INCHES DEEP, UPSLOPE AND ADJACENT TO THE WOOD POST TO ALLOW THE FILTER FABRIC TO BE BURIED. 4. WHEN STANDARD STRENGTH FILTER FABRIC IS USED, A WIRE MESH SUPPORT FENCE SHALL BE FASTENED SECURELY TO THE UPSLOPE SIDE OF 774E POSTS USING HEAVY-DUTY WIRE STAPLES AT LEAST 1 INCH LONG, 77E WIRES OR HOG RINGS THE WIRE SHALL EXTEND INTO THE TRENCH A MINIMUM OF 4 INCHES AND SHALL NOT EXTEND MORE THAN 36 INCHES ABOVE THE ORIGINAL GROUND SURFACE. 5. THE STANDARD STRENGTH FILTER FABRIC SHALL BE STAPLED OR WIRED TO 774E FENCE, AND 20 INCHES OF THE FABRIC SHALL BE EXTENDED INTO 774E TRENCH. THE FABRIC SHALL NOT EXTEND MORE THAN 36 INCHES ABOVE THE ORIGINAL GROUND SURFACE. FILTER FABRIC SHALL NOT BE STAPLED TO EXIS77NG TREES 6. WHEN EXTRA STRENGTH FILTER FABRIC AND CLOSER POST SPACING ARE USED, THE WIRE MESH SUPPORT FENCE MAY BE ELIMINATED. IN SUCH A CASE, THE FILTER FABRIC IS STAPLED OR WIRED DIRECTLY TO THE POSTS WITH ALL OTHER PROVISIONS OF STANDARD N07E 5 APPLYING. Z 774E TRENCH SHALL BE BACKFTLLED WITH 314-INCH MINIMUM DIAMETER WASHED GRA VEL. 8. FILTER FABRIC FENCES SHALL BE REMOVED WHEN THEY HAVE SERVED ]HEIR USEFUL PURPOSE BUT NOT BEFORE THE UPSLOPE AREA HAS BEEN PERMANENTLY STABILIZED. 9. FLTER FABRIC FENCES SHALL BE INSPECTED IMMEDIATELY AFTER EACH RAINFALL AND AT LEAST DAILY DURING PROLONGED RAINFALL. ANY REQUIRED REPAIRS SHALL BE MADE IMMEDIATELY. R 345 129 R/W SWALE OVERFLOW RAP TEMPORARY ER0S1ONISEDIMENTA 770N CONTROL NOTES 1. APPROVAL OF THIS EROSION AND SEDIMENTATION CONTROL (ESC) PLAN DOES NOT CONSTITUTE AN APPROVAL OF PERMANENT ROAD OR DRAINAGE DESIGN (E.G. SIZE AND LOCA77ON OF ROADS, PIPES, RESTRICTORS, CHANNELS, RETENTION FACILITIES, UTILITIES, ETC.) 2. THE IMPLEMENTATION OF THESE ESC PLANS AND THE CONSTRUCTION, MAINTENANCE, REPLACEMENT, AND UPGRADING OF THESE ESC FACIL177ES IS THE RESPONSIBILITY OF THE APPLICANT/ESC SUPERVISOR UN77L ALL CONSTRUC7701V IS APPROVED. 3. 774E BOUNDARIES OF THE CLEARING LIMITS SHOWN ON THIS PLAN SHALL BE CLEARLY FLAGGED BY SURVEY TAPE OR FENCING, IF REQUIRED, PRIOR TO CONSTRUCTION (SWDM APPENDIX D). 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 DURA77ON OF CONSTRUCTION. 4. STABILIZED CONSTRUCTION ENTRANCES SHALL BE INSTALLED AT 774E BEGINNING OF CONSTRUCTION AND MAINTAINED FOR THE DURA77ON 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 774E PROJECT. 5. THE ESC FACIL177ES SHOWN ON 7741S PLAN MUST BE CONSTRUCTED PRIOR TO OR IN CONJUNCTION WIN ALL CLEARING AND GRADING SO AS TO ENSURE 774AT THE TRANSPORT OF SEDIMENT TO SURFACE WATERS, DRAINAGE SYSTEMS, AND ADJACENT PROPERTIES IS MINIMIZED. 6. 774E ESC FACIL177ES SHOWN ON THIS PLAN ARE THE MINIMUM REQUIREMENTS FOR ANTICIPATED S17E CONDITIONS. DURING THE CONSTRUCTION PERIOD, 714ESE ESC FACIL177ES SHALL BE UPGRADED AS NEEDED FOR UNEXPECTED STORM EVENTS AND MODIFIED TO ACCOUNT FOR CHANGING S17E COND177ONS (E.G. ADDITIONAL COVER MEASURES, ADD177ONAL SUMP PUMPS, RELOCA77ON OF DITCHES AND SILT FENCES, PERIMETER PR07EC77ON ETC.). 7. THE ESC FACIL177ES SHALL BE INSPECTED DAILY BY THE APPLICANT/ESC SUPERVISOR AND MAINTAINED TO ENSURE CON77NUED PROPER FUNCTIONING. WRITTEN RECORDS SHALL BE KEPT OF WEEKLY REVIEWS OF THE ESC FACILI77ES. 8. ANY AREAS OF EXPOSED SOILS, INCLUDING ROADWAY EMBANKMENTS, THAT WILL NOT BE DISTURBED FOR TWO DAYS DURING THE WET SEASON OR SEVEN DAYS DURING THE DRY SEASON SHALL BE IMMEDIATELY STABILIZED WITH THE APPROVED ESC COVER METHODS (E.G., SEEDING, MULCHING, PLASTIC COVERING, ETC.). 9. ANY AREA NEEDING ESC MEASURES, NOT REQUIRING IMMEDIA TE A T7EN71ON, SHALL BE ADDRESSED WI THIN SEVEN (7) DAYS. 10. 774E ESC FACILITIES ON INACTIVE SITES SHALL BE INSPECTED AND MAINTAINED A MINIMUM OF ONCE A MONTH OR WT 7HIN 24 HOURS FOLLOWING A STORM EVENT. 11. AT NO 77ME 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. 12. 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 FUNC77ON 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. 13. COVER MEASURES WILL. BE APPLIED 1N CONFORMANCE WITH APPENDIX D OF THE SURF4CE WATER DESIGN MANUAL. 14. PRIOR TO THE BEGINNING OF 174E WET SEASON (OCT. 1), ALL DISTURBED AREAS SHALL BE REVIEWED TO IDEN77FY WHICH ONES CAN BE SEEDED IN PREPARA77ON FOR 774E 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 DDES INSPECTOR FOR REVIEW. GRA TE BYPASS EXCESS FABRIC TO PREVENT FILTER FROM FALLING INTO STRUCTURE FABRIC v 0 b 0 ENT REMOVAL DRAINAGE STRUCTURE FlL 7ERED WA TER STORM DRAIN PROTECTION INSERT SEC77ON A -A TE ME GEOTEX77LE F PLAN VIEW CATCH BASIN PROTECTION DETAIL NOT TO SCALE R/W SEEDING NOTES 1. SEEDBED PREPARA77ON MAY INCLUDE THE FOLLOWING: A. IF INFER77LE OR COARSE TEXTURED SUBSOIL WRL BE EXPOSED DURING GRADING, STOCKPILE TOPSOIL AND RESPREAD IT OVER THE FINISHED SLOPE AND ROLL IT TO PROVIDE A FIRM BASE. B. IF CONSTRUCTI0N FILLS HAVE LEFT SOIL EXPOSED WITH A LOOSE, ROUGH OR IRREGULAR SURFACE, TRACK WALK UP SLOPE. C. IF CUTS OR CONSTRUCTION EQUIPMENT HAVE LEFT A TIGHTLY COMPACTED SURFACE, BREAK WITH CHISEL PLOW OR 0774ER SUITABLE EQUIPMENT. PERFORM ALL CUL TURAL OPERA 77ONS ACROSS OR A T RIGHT ANGLES TO THE SLOPES (CONTOURED). THE SEEDBED SHOULD BE FIRM WITH A FAIRLY FINE SURFACE AFTER ROUGHENING. 2. FER77LIZAT70N - AS PER SUPPLIER'S RECOMMENDATIONS. DEVELOPMENTS ADJACENT TO WATER BODIES MUST USE NONPHOSPHOROUS FERTILIZER. J. HYDROSEEDING APPLICA77ONS W77H APPROVED SEED -MULCH -FERTILIZER MIXTURES MA Y ALSO BE USED. 4. SEEDING - APPL Y APPROPRIA TE MIXTURE TO THE PREPARED SEEDBED A T A RA TE OF 120 LBS/ACRE. COVER THE SEED WITH TOPSOIL OR MULCH NO DEEPER THAN ONE-HALF INCH. TEMPORARY EROSION CONTROL PROPOR77ONS PERCENT PERCENT SEED MIX BY WEIGHT PURITY GERMINA77ON CHEWINGS OR RED FESCUE 40X 98 90 ANNUAL OR PERENNIAL RYE 4OX 98 90 REDTOP OR COLONIAL BENTGRASS 10X 92 85 W 17E DUTCH CLOVER lox 98 90 CONS772uOM SEQUENCE 1. SCHEDULE A PRE -CONSTRUCTION CONFERENCE WIT7-1 THE DDES S17E INSPECTOR BY CALLING (206) 296-6642 2. FLAG OR FENCE CLEARING LIMITS. J. POST N077CE OF CONSTRUCTION AC770TY SIGN WITH NAME AND PHONE NUMBER OF ESC SUPERVISOR. ESC SUPERVISOR IS VERNE WOLLEY (425) 754-8103 4. INSTALL CATCH BASIN PR07EC77ON AS SHOWN ON PLANS. 5. GRADE AND INSTALL CONSTRUCTION ENTRANCE. 6. INSTALL PERIMETER PR07ECT70N (2 ROWS OF SILT FENCE ALONG WEST AND NORTH SENSITIVE AREA BOUNDARY LINES) AND ORANGE CONSTRUCTION FENCE. 7 CONSTRUCT TEMPORARY SUMPS, TEMPORARY SEDIMENT BASINS, PERMANENT DETENT70N DISCHARGE STRUCTURES AND ASSOCIATED PIPES. 8. GRADE AND STABILIZE ROADS PER TEMPORARY SUBGRADE SECTION, THIS SHEET. 9. CONSTRUCT SURFACE WATER CONTROLS (INTERCEPTOR SWALES, PIPE SLOPE DRAINS) SIMULTANEOUSLY WITH CLEARING AND GRADING FOR PROJECT DEVELOPMENT. 10. PLACE S150 (STRAW FABRIC) OVER 2.1 SLOPES TO PROTECT FROM EROSION AS REQUIRED. 11. MAINTAIN EROSION CONTROL MEASURES IN ACCORDANCE WI7H KING COUNTY STANDARDS AND MANUFACTURER'S RECOMMENDATIONS. 12. RELOCATE SURFACE WATER CONTROLS AND EROSION CONTROL MEASURES OR INSTALL NEW MEASURES SO THAT AS S17E CONDITIONS CHANGE 714E EROSION AND SEDIMENT CONTROL IS ALWAYS IN ACCORDANCE WITH THE KING COUNTY EROSION AND SEDIMENT CONTROL STANDARDS 13. UPON COMPLETION OF THE PROJECT, ALL DISTURBED AREAS MUST BE STABILIZED AND BEST MANAGEMENT PRACTICES REMOVED IF APPROPRIATE. GRADING NO1FS 1. ALL FILLS LOCATED WITHIN THE BUILDING ENVELOPE SHALL BE COMPACTED TO A MINIMUM OF 90 PERCENT OF MAXIMUM DENSITY PER U.B.C. 33134. OR AS OTHERWISE REQUIRED BY THE GEOTECHNICAL CONSULTANT TO BE CERTIFIED AS "ENGINEERED, STRUCTURAL FILL SUITABLE FOR CONVENTIONAL FOUNDA 77ONS AND HAVING ADEQUATE BEARING CAPACITY FOR RESIDEN77AL STRUCTURES" WET SEASON SPECIAL PROVISIONS 1. THE ALLOWED TIME THAT A DISTURBED AREA MAY REMAIN UNWORKDED WITHOUT COVER MEASURE IS REDUCED TO TWO CONSECUTIVE WORKING DAYS, RATHER THAN SEVEN. 2. STOCKPILES AND STEEP CUT AND FILL SLOPES ARE TO BE PROTECTED IF UNWORKED FOR MORE THAN 12 HOURS 3. COVER MATERIALS SUFFICIENT TO COVER ALL DISTURBED AREAS SHALL BE STOCKPILED ON SITE: 4. ALL AREAS THAT ARE TO BE UNWORKED DURING THE WET SEASON SHALL BE SEEDED WI THIN ONE WEEK O OF THE BEGINNING OF THE WET SEASON. 5. MULCH IS REQUIRED TO PROTECT ALL SEEDED AREAS. 6. FIFTY LINEAR FEET OF SILT FENCE (AND THE NECESSARY STAKES) PER ACRE OF DISTURBANCE MUST BE STOCKPILED ON SITE. 7. CONSTRUCTION ROAD AND PARKING LOT STABILIZATION ARE REQUIRED FOR ALL SI7ES UNLESS THE S17E IS UNDERLAIN BY COARSE -GRAINED SOIL. 8. SEDIMENT RETENTION IS REQUIRED UNLESS NO OFFSI7E DISCHARGE IS ANTICIPATED FOR THE SPECIFIED DESIGN FLOW. 9. SURFACE WATER CONTROLS ARE REQUIRED UNLESS NO OFFSI7E DISCHARGE IS ANTICIPATED FOR THE SPECIFIED DESIGN FLOW. 10. PHASING AND MORE CONSERVATIVE BMPS MUST BE EVALUATED FOR CONSTRUCTION AC77WTY NEAR SURFACE WATERS 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. 12. 774E FREQUENCY OF MAINTENANCE REVIEW INCREASES FROM MONTHLY TO WEEKLY. MA/N7FNANCE STANDARDS (FOR STABILIZED CONSTRUCTION EN714ANWJ 1. QUARRY SPALLS (OR HOG FUEL) SHALL BE ADDED IF THE PAD IS NO LONGER IN ACCORDANCE WITH THE SPECIFICATIONS. 2 IF THE ENTRANCE IS NOT PREVENTING SEDIMENT FROM BEING TRACKED ONTO PAVEMENT, THEN ALTERNATE MEASURES TO KEEP THE STREETS FREE OF SEDIMENT SHALL BE USED. THIS MAY INCLUDE STREET SWEEPING, AN INCREASE IN THE DIMENSIONS OF THE ENTRANCE, OR THE INSTALLATION OF A WHEEL WASH. IF WASHING IS USED, IT SHALL BE DONE ON AN AREA COVERED WITH CRUSHED ROCK, AND WASH WATER SHALL DRAIN TO A SEDIMENT TRAP OR POND. J. ANY SEDIMENT THAT IS TRACKED ONTO PAVEMENT SHALL BE REMOVED IMMEDIATELY BY SWEEPING. 774E SEDIMENT COLLECTED BY SWEEPING SHALL BE REMOVED OR STABILIZED ON -SITE. THE PAVEMENT SHALL NOT BE CLEANED BY WASHING DOWN THE STREET, EXCEPT WHEN SWEEPING IS INEFFECTIVE AND THERE IS A THREAT TO PUBLIC SAFETY. IF IT IS NECESSARY TO WASH THE STREETS; THE CONSTRUCTION OF A SMALL SUMP SHALL BE CONSIDERED. THE SEDIMENT WOULD THEN BE WASHED INTO THE SUMP. 4. ANY ROCK SPALLS THAT ARE LOOSENED FROM THE PAD AND END UP ON THE ROAD WAY SHALL BE REMOVED IMMEDIATELY. 5. IF VEHICLES ARE ENTERING OR EX177NG THE SITE AT POINTS 077-TER THAN CONSTRUCTION ENTRANCE(S), FENCING SHALL BE INSTALLED TO CONTROL TRAFFIC. 4j'9k _2% 2,9 ul Ui* . _ ! 29i NOT TO SCALE Checked for Compliance to City Standards A 51a9 Q 2012 TRIAD ASSOCIATES1 /\ TRLkD ASSOCIATES 12112 115th Ave. NE Kirkland, WA 98034-6929 425.821.8448 425.821.3481 fax 800.488.0756 toll free www. triadassociates. net A m x RICHARD A. TOMKIN4 PE PROJECT MANAGER MARK S HARRISOR PLS PROJECT SURVEYOR RICHARD A. TOMKINS; PE PROJECT ENGINEER JEFFREY L COX ASLA PROJECT LANDSCAPE ARCHITECT FIRST SUBMITTAL DATE: 8120107 SCALE: HORIZ.: N/A VW.:NIA V STAMP NOT VALID UNLESS SIGNED AND DATED JOB N0. O 1- O4 7 SHEET N0. 70F 2 1 m z z 1 o O a ' z w D