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HomeMy WebLinkAboutSWP272255(1) STORM DRAINAGE REPORT FOR RAYMOND AVENUE CENTER RENTON, WASHINGTON BY 2 '— 2 BUSH, ROED & HITCHINGS 2009 MINOR AVENUE EAST SEATTLE, WA 98102 (206) 323-4144 �� ��a/ oe� CONTACT: JOHN E. ANDERSON, P.E. ��• D RH JOB NO. 92233 . 02 o K' co w r "dp 26878 <y� MARCH 26, 1996 ISTE SIDNAL 3�2�/R6 EXPIRES 12/1/11l Raymond Avenue Center is a 10 .39 acre site located at the southwest quadrant of the intersection of Southwest 19th Street and Raymond Avenue South. The proposed development woud ccur on Parcel B. Development would include the construction of a 99, 900 square foot building and associated parking. Spring Brook Creek defines the southern and western boundary of the site. The original easement for Spring Brook Creek did not coincide with the actual stream location. Bush, Roed & Hitchings has prepared a lot line adjustment which defines the easements according to the surveyed location of the stream. Lot lines shown on the documents submitted for site plan and shoreline review reflect the most current survey information. Several years ago, the site was filled to approximately elevation 18 . Fill slopes toe down to the banks of Spring Brook Creek on the southern and western boundary. On the eastern boundary, the fill slopes toe down approximately 60 feet west of the east property line. Areas east of the fill slopes are classified wetlands. A 60 inch culvert discharges into a ditch on the west side of Raymond Avenue. The ditch is located within the 19th Street right-of-way just north of the north property line. Existing drainage maps indicate the area tributary to the ditch include Panther Creek Wetlands. From the 60 inch culvert, the ditch flows west to Spring Brook Creek. Existing grades on the developable areas are approximately 9 to 10 feet higher than surrounding grades . The ground surface where the proposed development will occur is flat. Tall grasses cover the area. There are no significant trees located within the buildable area. Storm water run-off from the site sheet flows to the surrounding low lands . No defined drainage courses were observed on the site. The proposed site plan maintains a minimum 50 foot setback from Spring Brook Creek and a 25 foot setback from the surrounding wetlands . Storm water run-off from the developed areas will sheet flow to catch basins located in the parking lot. The storm water will then be conveyed directly to a combine wetpond/detention pond facility. A wetpond is required because the development is located next to Spring Brook Creek, and has more than one acre of impervious surface area subject to vehicular traffic. Also, since the storm water will discharge into Spring Brook Creek the detention volume will be calculated using Department of Fisheries guidelines. These standards require a peak discharge rate from the detention system equal to 1/2 the pre-developed 2 year rate for a 10 year developed storm inflow. Peak discharge rates from the detention system for storm events greater than the 10 year match pre-developed peak rates for the same storm event. Analysis of the combined wetpond/detention pond design shows that it performs significantly better than the Department of Fisheries guidelines . Initial sizing was based on maximizing the available area. The goal was to make the detention volume shallow. By making the detention volume shallow, there is not sufficient head pressure to reach the pre-developed 25 year and 100 year peak discharge rates . The calculations show the developed 25 year and 100 year storm will be discharged at approximately 1/2 the pre- developed 10 year peak rate. Therefore, development of this site will reduce the peak rates for all storm events. Volume provided by the wetpond exceeds the required volume by approximately a factor of three. This is also a result of maximizing the available area. The design guidelines require a 3 foot minimum depth plus 1 foot of sediment storage. Maintaining the depth requirement across the pond provides a storage volume of approximately 28, 846 cubic feet . The required volume is approximately 8, 514 cubic feet. Therefore, the storm water quality will be significantly better than required by Department of Fisheries guidelines . The additional wetpond volume will also mitigate the two small areas filled within the 100 year flood plain (below elevation 16) . reports/92233. 02 I LONGACRES RACE TRACK \ r m _ RFti N m T o tid�d� m OcFlc . S.w = n y� D \ THOMAS AV W. A O RAYMOND AV S.w. Z D (VALLEY FREEWAY) STATE SIGN ROUTE 167 ' o SUStINOtON - CG -�=Culvert I � 19 RM333 pI 1 \I RM334 j6 wi ZONE X FW Z ViaELI I II ' I I I i � � I , I I II ZONE X I ii I 4f I I ZONE ZONE X j X I , ,,�FFT RFN-I ]88 16 • BRIDGE UNDER o\_ CONSIRUCIIUN r - Sour nvFs' �7rt, RM338 STREET Flu-- \/,J �TH i t J I CO Yp �P CorAL t Z�) t � , (D,Z6, G FH hti �g. CURB 18.40 BREAK / r' I• i b / 59 / IE-14.00 r r 1 I t o w . I (n L---------- -----� SS MH I TE-19.00+ � IE-11.28 EXIST. SS MH iE�1�.16 IE-10.04 ASS r TH A NUE + TE- CH EX � I IE-1 64 �� I 0' SAN SEWER RAYM AVENUE S IE-10. — '�;5;. tir- 7 AM "PI MMM EK NMI sh va% N, OVA IRTI ILI . . �' !��'►%'fir' .!'' .�,-P sor IL PMwh �►�, INAI IrMAN i' Mna • WAS►�r.;•� I= ti d ..d ��•r � it���sab� a t � ►�s�a��1 � v • J . • • `EItZ �a 'Wlw. .�. ,ice I all 11 wrj m,�7 ��� �. •�w�� � 1 ,�► ,, .., �w `J. , KING COUNTY, WASHINGTON, SURFACE WATER DESIGN MANUAL —ABLE 3.5.213 SCS WESTERN WASHINGTON RUNOFF CURVE NUMBERS SCS WESTERN WASHINGTON RUNOFF CURVE NUMBERS (Published by SCS in 1982) Runoff curve numbers for selected agricultural, suburban and urban land use for Type 1A rainfall distribution, 24-hour storm duration. CURVE NUMBERS BY HYDROLOGIC SOIL GROUP LAND USE DESCRIPTION A B C D Cultivated land(1): winter condition 86 91 94 95 Mountain open areas: low growing brush and grasslands 74 82 89 92 65 78 85 89 Meadow or pasture: Wood or forest land: undisturbed or older second growth 42 76 81 72 Wood or forest land: young second growth or brush 55 81 86 Orchard: with cover crop. 81 88 92 94 Open spaces, lawns, parks, golf courses, cemeteries, landscaping. good condition: grass cover on 75% 68 (2� 86 90 or more of the area fair condition: grass cover on 50% ,7 85 90 92 to 75% of the area Gravel roads and parking lots :E 76 85 89 91 Dirt roads and parking lots 72 82 87 89 i Impervious surfaces, pavement, roofs, etc. 98 98 98 98 Open water bodies: lakes, wetlands, ponds, etc. 100 100 100 100 Single Family Residential (2) Dwelling Unit/Gross Acre % Impervious (3)1.0 DU/GA 15 Separate curve number 1.5 DU/GA 20 shall be selected 2.0 DU/GA 25 for pervious and 2.5 DU/GA 30 impervious portion 3.0 DU/GA 34 of the site or basin 3.5 DU/GA 38 4.0 DU/GA 42 4.5 DU/GA 46 5.0 DU/GA 48 5.5 DU/GA 50 6.0 DU/GA 52 6.5 DU/GA 54 7.0 DU/GA 56 Planned unit developments, % impervious condominiums, apartments, must be computed commercial business and industrial areas. (1) For a more detailed description of agricultural land use curve numbers refer to National Engineering Handbook, Section 4, Hydrology, Chapter 9, August 1972. (2) Assumes roof and driveway runoff is directed into street/storm system. (3) The remaining pervious areas (lawn) are considered to be in good condition for these curve numbers. 1 3.5.2-3 11/92 = 3/10/96 Bush, Roed & Hitchings, Inc. page 1 Raymond Industrial Center John E. Anderson, P.E. 92233 ------------------ ------------------------------------------ BASIN SUMMARY BASIN ID: B1 NAME: 2 YEAR EXISTING SBUH METHODOLOGY TOTAL AREA. . . . . . . : 5. 24 Acres BASEFLOWS: 0.00 cfs RAINFALL TYPE. . . . : USER1 PERVIOUS AREA PRECIPITATION. . . . : 2 .00 inches AREA. . : 5. 24 Acres TIME INTERVAL. . . . : 10.00 min CN. . . . : 80.00 TIME OF CONC. . . . . : 30. 30 min IMPERVIOUS AREA ABSTRACTION COEFF: 0.20 AREA. . : 0.00 Acres CN. . . . . 98.00 PEAK RATE: 0 . 31 cfs VOL: 0. 25 Ac-ft TIME: 490 min BASIN ID: B2 NAME: 10 YEAR EXISTING SBUH METHODOLOGY TOTAL AREA. . . . . . . : 5. 24 Acres BASEFLOWS: 0.00 cfs RAINFALL TYPE. . . . : USER1 PERVIOUS AREA PRECIPITATION. . . . : 2.90 inches AREA. . : 5.24 Acres TIME INTERVAL. . . . : 10.00 min CN. . . . : 80.00 TIME OF CONC. . . . . : 30.30 min IMPERVIOUS AREA ABSTRACTION COEFF: 0. 20 AREA. . : 0.00 Acres CN. . . . . 98 .00 PEAK RATE: 0.89 cfs VOL: 0.51 Ac-ft TIME: 480 min BASIN ID: B3 NAME: 25 YEAR EXISTING SBUH METHODOLOGY TOTAL AREA. . . . . . . : 5.24 Acres BASEFLOWS: 0.00 cfs RAINFALL TYPE. . . . : USER1 PERVIOUS AREA PRECIPITATION. . . . : 3.40 inches AREA. . : 5. 24 Acres TIME INTERVAL. . . . : 10.00 min CN. . . . : 80.00 TIME OF CONC. . . . . : 30. 30 min IMPERVIOUS AREA ABSTRACTION COEFF: 0. 20 AREA. . : 0.00 Acres CN. . . . . 98.00 PEAK RATE: 1. 27 cfs VOL: 0.68 Ac-ft TIME: 480 min t 3/10/96 Bush, Roed & Hitchings, Inc. page 2 Raymond Industrial Center John E. Anderson, P.E. 92233 BASIN SUMMARY BASIN ID: B4 NAME: 100 YEAR EXISTING SBUH METHODOLOGY TOTAL AREA. . . . . . . : 5. 24 Acres BASEFLOWS: 0.00 cfs RAINFALL TYPE. . . . : USER1 PERVIOUS AREA PRECIPITATION. . . . : 3.90 inches AREA. . : 5. 24 Acres TIME INTERVAL. . . . : 10.00 min CN. . . . : 80.00 TIME OF CONC. . . . . : 30. 30 min IMPERVIOUS AREA ABSTRACTION COEFF: 0.20 AREA. . : 0.00 Acres CN. . . . . 98.00 PEAK RATE: 1.68 cfs VOL: 0.86 Ac-ft TIME: 480 min BASIN ID: B5 NAME: 2 YEAR DEVELOPED SBUH METHODOLOGY TOTAL AREA. . . . . . . : 5. 24 Acres BASEFLOWS: 0.00 cfs RAINFALL TYPE. . . . : USER1 PERVIOUS AREA PRECIPITATION. . . . : 2.00 inches AREA. . : 0. 31 Acres TIME INTERVAL. . . . : 10.00 min CN. . . . : 80.00 TIME OF CONC. . . . . : 16.30 min IMPERVIOUS AREA ABSTRACTION COEFF: 0.20 AREA. . : 4.93 Acres CN. . . . . 98.00 PEAK RATE: 2.05 cfs VOL: 0.74 Ac-ft TIME: 480 min BASIN ID: B6 NAME: 10 YEAR DEVELOPED SBUH METHODOLOGY TOTAL AREA. . . . . . . : 5. 24 Acres BASEFLOWS: 0. 00 cfs RAINFALL TYPE. . . . : USER1 PERVIOUS AREA PRECIPITATION. . . . : 2. 90 inches AREA. . : 0. 31 Acres TIME INTERVAL. . . . : 10.00 min CN. . . . : 80.00 TIME OF CONC. . . . . : 16. 30 min IMPERVIOUS AREA ABSTRACTION COEFF: 0. 20 AREA. . : 4.93 Acres CN. . . . . 98.00 PEAK RATE: 3 .08 cfs VOL: 1. 13 Ac-ft TIME: 480 min 1 S 3/10/96 Bush, Roed & Hitchings, Inc. page 3 Raymond Industrial Center John E. Anderson, P.E. -� 92233 BASIN SUMMARY BASIN ID: B7 NAME: 25 YEAR DEVELOPED SBUH METHODOLOGY TOTAL AREA. . . . . . . : 5.24 Acres BASEFLOWS: 0.00 cfs RAINFALL TYPE. . . . : USER1 PERVIOUS AREA PRECIPITATION. . . . : 3 . 40 inches AREA. . : 0 . 31 Acres TIME INTERVAL. . . . : 10. 00 min CN. . . . : 80.00 TIME OF CONC. . . . . : 16. 30 min IMPERVIOUS AREA ABSTRACTION COEFF: 0.20 AREA. . : 4 . 93 Acres CN. . . . . 98 .00 PEAK RATE: 3 . 65 cfs VOL: 1. 34 Ac-ft TIME: 480 min BASIN ID: B8 NAME: 100 YEAR DEVELOPED SBUH METHODOLOGY TOTAL AREA. . . . . . . : 5. 24 Acres BASEFLOWS: 0.00 cfs RAINFALL TYPE. . . . : USER1 PERVIOUS AREA PRECIPITATION. . . . : 3. 90 inches AREA. . : 0. 31 Acres TIME INTERVAL. . . . : 10.00 min CN. . . . : 80. 00 TIME OF CONC. . . . . : 16.30 min IMPERVIOUS AREA ABSTRACTION COEFF: 0. 20 AREA. . : 4. 93 Acres CN. . . . . 98 . 00 PEAK RATE: 4 . 22 cfs VOL: 1 . 56 Ac-ft TIME: 480 min BASIN ID: B9 NAME: PTWQ VOLUME FOR WETPOND SBUH METHODOLOGY TOTAL AREA. . . . . . . : 5. 24 Acres BASEFLOWS: 0.00 cfs RAINFALL TYPE. . . . : USERI PERVIOUS AREA PRECIPITATION. . . . : 0.67 inches AREA. . : 0 . 31 Acres TIME INTERVAL. . . . : 10.00 min CN. . . . : 80 . 00 TIME OF CONC. . . . . : 16. 30 min IMPERVIOUS AREA ABSTRACTION COEFF: 0 . 20 AREA. . : 4. 93 Acres CN. . . . . 98. 00 PEAK RATE: 0 .54 cfs VOL: 0. 20 Ac-ft TIME: 480 min } 2 3/10/96 Bush, Roed & Hitchings, Inc. page 1 Raymond Industrial Center John E. Anderson, P.E. 92233 HYDROGRAPH SUMMARY PEAK TIME VOLUME HYD RUNOFF OF OF Contrib NUM RATE PEAK HYDRO Area cfs min. cf-ACFt Acres --------------------------------------------- --------------------------------------------- 1 0. 314 490 10699 cf 5. 24 Z -ram 2 0. 888 480-- -22360 cf - - 5.24 3 1 . 272 z3 cS ' �Ob `(R EX1STIlJ� . —8U --49081—cf ---5�z� Z '-- -D--- -1- 1 Ft_a>�, IN 10 `{2 pEVE�a?'cC� �r�lFloW C f 24- 9 0.544 0 8 514-c f------ --2�F--- -p Tv.► Fo R %+ET tO N D \!o L.0 v�E ------------ 11 0.153 1470 -2 2 217-_c f--------5.2 ----- -- ____________ 'PoNv REFERS£ _ 12 0.426 13 0.675 900 40325 cf 5.24 boa•{ poNb iz�L�tSS �- bETE't1'r101�l PofiD t�E51(��.1 i=nL_�,.�I� F�SNE'@,��5 DC-S��t�l ST►�.1.lDR�'DS. I . �.t_t.owAt3uE REI.ER5c- 12p.TE Fosz 10 `1Gx7- QEVC�oPC-p INFt � Eo u AL5 y2 P2� - t7 E V�t_.o Pc D �C1RK- 2v.TE. Io �E�t'(Z C7EvELoPEb � ® = 3 o �IG'FS p�Ter�T�oN poNv �E��s� _ �� _ o, �5'� c.�s � C�. t51��s ✓ ;7-'ATE5 Fop. Z 5 Y e pt tz 17EvIGW��D ►NG�owS (AUS r I�OT �Qt - t7tvEwP�t� PEp.1G 1z�'CIcS. I7E?ENTt oN T'UND RE�'r-�S£= O = O. 42(oC.�S ✓ E - DE�1t�.DQED 100 `{RAID_® = I (o�Z GAS l7E?�t�►'n o r.1 PoN t� '�E 1.EI�s� = ►� = p , (c"15 «S ✓ DETE►JT10Q ?0Q> eXGEEDs Fie t-�[QZtEs Srz,►..IpP�iZQ �T Pv►.1 D VOL.UM E PeCS?V1 e Eb AISQ UALS 'PTvuQ sTOtZM VOLUW E at = V v L = 3/10/96 Bush, Roed & Hitchings, Inc. page 2 Raymond Industrial Center John E. Anderson, P.E. 92233 STORAGE STRUCTURE LIST STORAGE LIST ID No. 1 Description: DETENTION POND AREA$ FRDr,,\ )L'�,,u To Cpb d E616 sl S-L-S\1 , A ''e E�. o "7 Zo SF -1 o S �1 O Z SF vv �Por�l D 2�, o to 2d1 SF �vo�= 2� �4Cou=� I o 10 1Z 'I °12 SF �G'CGI.IT u� VOLLUMG 1 1 , O 13 8'12 SF roz too \(2 ST01ZNA I2o 14 9 q4 5 r - -- - - -- ,4'b-X wA--Ee EI.EVATto� I� ,b ICo 13G7 5r FOR too \R STORM 14 I'7 ZOA 5F = lz,Oat �.C7DIT� ONA.� Vo�.uMtr 15 ,0 ► �b 4�35F Ptzo�tnED t 3/10/96 Bush, Roed & Hitchings, Inc. page 3 Raymond Industrial Center John E. Anderson, P.E. 92233 DISCHARGE STRUCTURE LIST MULTIPLE ORIFICE ID No. 1 Description: FISHERIES DESIGN RELEASE Outlet Elev: 9.00 Elev: 9.00 ft Orifice Diameter: 1.8100 in. Elev: 12.00 ft Orifice 2 Diameter: 8.0000 in. OVC z ,Et�v. 14-0 ��- g, a 1210 i i 3/10/96 Bush, Roed & Hitchings, Inc. page 4 Raymond Industrial Center John E. Anderson, P.E. > 92233 LEVEL POOL TABLE SUMMARY MATCH INFLOW ST DI <-PEAK-> STORAGE <--------DESCRIPTION---------> (cfs) (cfs) id id <-STAGE> id VOL (cf) --------------- 1/2-2 YR. FOR 10 YR . . . . . . . . . . 0. 31 3 .08 1 1 11.98 11 397 25 YEAR STORM . . . . . . . . . . . . . . . . 1. 27 3 .65 1 1 12.05 12 408 100 YEAR STORM . . . . . . . . . . . . . . . 1.68 4.22 1 1 12.09 13 415 File Basin Hydrograph Storage Discharge Level pool Bush, Roed & Hitchings, Inc. 2 ROUTING COMPARISON TABLE MATCH INFLOW STO DIS PEAK PEAK OUT DESCRIPTION PEAK PEAK No. No. STG OUT HYD 1/2-2 YR. FOR 10 YR 0.31 3 .08 1 1 11.98 0.15 11 25 YEAR STORM 1. 27 3 .65 1 1 12 .05 0.43 12 100 YEAR STORM 1.68 4.22 1 1 12.09 0.68 13 ==========>Done<============ F10 to Exit Available Memory remaining: 151037 bytes Current Data Set Name: a:\92233 File Basin Hydrograph Storage Discharge Level pool Bush, Roed & Hitchings, Inc. 2 ROUTING COMPARISON TABLE MATCH INFLOW STO DIS PEAK PEAK OUT DESCRIPTION PEAK PEAK No. No. STG OUT HYD 1/2-2 YR. FOR 10 YR 0. 31 3 .08 1 1 11.98 0.15 11 25 YEAR STORM 1. 27 3.65 1 1 12.05 0.43 12 100 YEAR STORM 1.68 4. 22 1 1 12 .09 0.68 13 ==========>Done<============ F10 to Exit Available Memory remaining: 151037 bytes Current Data Set Name: a:\92233 BUSH,ROED&HITCHINGS,INC. Job CIVIL ENGINEERS &LAND SURVEYORS SHEET NO. OF M09 Minor Avenue East Seattle,WA 98102 CALCULATED BY DATE (206)323-4144 B R H (206)323-7135 - Fax CHECKED BY DATE SCALE 6Zs L -For 174f- Hyp&A-0LAC_ s rw ,)sue, 'CA-" I)LATE 4 F0;.J7-$ 4,rA 2-) 11 rn nJ�c'� 3.) 3 o m I n 57 �"�) (p0 rn,n��-P.� � �y = ��• 4' 112� � (70 0'm5 S --'� Tl+! 5? F. L.v2VE A Z lrjPaT ,4 µ�•,a2.�G� 77 6 bc,'VCO [o✓„rr7'rnvA,F4 H� Z "mLve PRODUCT 204 1(Srpk$heeds)205"1(PaW)J pm Inc.Groton,Mass 01471 To Order PHONE TOLL FREE 1"800.225-6380 BUSH, ROED & HITCHINGS,INC. JOB CIVIL ENGINEERS & LAND SURVEYORS SHEET NO OF 2009 Minor Avenue East Seattle,WA 98102 CALCULATED BY L3�p DATE yy r' (206)323-4144 CHECKED BY C) DATE ! B (206)323-7135 - Fax SCALE E S t o cot-)!e-o Li TH.LG. Fad-�oNf!.1. V.. AT—) .. ..•.. 10Q. ......_ j-.A-C-m- T1A.e U.P.pFk7(,:.;._. ..V£42 . ... . FrLor... . ..... 7 K-1 _G�, . .__C�Jti1't'. C ........ 1ri�1T._L .. 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P.E. storm disk-92233 HYDROGRAPH SUMMARY PEAK TIME VOLUME HYD RUNOFF OF OF Contrib NUM RATE PEAK HYDRO Area cfs min. cf-AcFt Acres 1 0.298 490 10148 cf 4 .97 2 0. 843 480 21207 cf 4.97 3 1 . 206 480 28097 cf 4.97 4 1 .596 480 35348 cf 4.97 5 1 .955 480 30824 cf 4.97 6 2.932 480 46683 cf 4.97 7 3 .474 480 55555 cf 4. 97 8 4 .016 480 64455 cf 4. 97 9 0. 515 480 8068 cf 4 .97 11 0.129 1470 19342 cf 4.97 12 0. 397 1450 26581 cf 4.97 13 0.504 1030 35290 cf- 4.97 14 0.281 480 6157 cf 1 .65 EA4T gAsir.1 15 0.431 480 9441 cf 2.53 ►a.R-TH S,"10 16 0. 511 480 11194 cf 3 . 00 \(JEsT eAc>u-1 KING COUNTY , WASHINGTON , SURFACE WATER DESIGN MANUAL 5.4.5.1 SEDIMENT TRAP i Code: ST Symbol: Purpose To remove sediment from runoff originating from disturbed areas of the site. Sediment traps are typically designed to only remove sediment as small as medium silt (0.02 mm). As a consequence, they usually only result in a small reduction in turbidity. Conditions of Use 1. A sediment trap shall be used where the contributing drainage area is 3 acres or less. Design and Installation Specifications 1. See Figure 5.4.5.1 A for detail. 2. If permanent runoff control facilities are part of the project, they should be used for sediment retention (see the introduction to this section). 3. To determine the trap geometry, first calculate the design surface area (SA) of the trap, measured at the invert of the weir . Use the following equation: SA = FS(02Ns), where: 02 = Design inflow based on the peak discharge from the developed 2-year, 24-hour design storm from the contributing drainage area as computed in the hydrologic analysis. The 10-year, 24-hour design storm shall be used if the project size, expected timing and duration of construction, or downstream conditions warrant a higher level of protection. If no hydrologic analysis is required, the rational method may be used (Section 4.3.3). Vs = The settling velocity of the soil particle of interest. The 0.02 mm (medium silt) particle with an assumed density of 2.65 g/cm3 has been selected as the particle of interest and has a settling velocity (Vs) of 0.00096 ft/sec. FS = A factor of safety of 2 to account for non-ideal settling. Therefore, the equation for computing surface area becomes: SA =2 x Q2/0.00096 or 2080 square feet per cfs of inflow NOTE: Even if permanent facilities are used, they must still have a surface area that is at least as large as that derived from the above formula. If they do not, the pond must be enlarged. 4. To aid in determining sediment depth, all traps shall have a staff gauge with a prominent mark 1 foot above the bottom of the trap. 5.4.5.1-1 11/94 KING COUNTY , WASHINGTON , SURFACE WATER DESIGN MANUAL FIGURE 5.4.5.1A SEDIMENT TRAP SURFACE AREA DETERMINED - AT TOP Of WEIR 4' MIN. 1: MIN. OVERFLOW I' WIN. f- 1' MIN. FLAT BOTTOM RIPRAP 3/4"-1.5" 2"-4" ROCK WASHED GRAVEL GEOTEXTILE NOTE: TRAP MAY BE FORMED BY BERM OR BY DISCHARGE TO STABILIZED PARTIAL OR COMPLETE EXCAVATION CONVEYANCE, OUTLET OR LEVEL SPREADER CROSS-SECTION -- 6' MIN. 1' MIN. DEPTH OVERFLOW SPILLWAY -I(I-III-III=1 I I-I Ii=1 i 1=1 i 1=1T►=1 i I-I I�I I I I_I i i=i i 1=1 11=1Tr=1 I r- NATIVE SOIL OR I I II I I{I 2iN 4 ROCK COMPACTED BACKFILL 1 f' t -III _ MIN. 1' DEPTH 3/4"-1.5" GEOTEXTILE -1 I{-III-III-III-III-{ 1=1 I I 11=1 I I- WASHED GRAVEL TRAP OUTLET Maintenance Standards 1. Sediment shall be removed from the trap when it reaches 1 foot in depth. 2. Any damage io the trap embankments or slopes shall be repaired. 5.4.5.2 SEDIMENT POND n Code: SP Symbol: Purpose To remove sediment from runoff originating from disturbed areas of the site. Sediment traps are typically designed to only remove sediment as small as medium silt (0.02 mm). As a consequence, they usually reduce turbidity only slightly. Conditions of Use 1. A sediment pond shall be used where the contributing drainage area is 3 acres or more. 5.4.5.2-1 11/94 BUSH,ROED& HITCHINGS, INC. JOB CIVIL ENGINEERS & LAND SURVEYORS SHEET NO. OF 2009 Minor Avenue East Seattle,WA 98102 CALCULATED BY DATE (206)323-4144 CHECKED BY DATE B R H (206)323-7135 • Fax SCALE �cJE�s� gas t '1, x 5 I_C-t� 0._006)0040 . .........._r. _ o�-�. _.........................2..._x. d- .._ . _. .0.__.ov©. cP . - 2 __s. .. ... .. .. .... ..... .........._........... .. ...,.............;...........: - .. .. _ Albi�J - . _ _ _ .... / _ _ .`b5�. �2. _ ._............____ _ _ _ ........! A =Lo.�3__ (--e2 �.��s��.o ��_ coa o ►o�-aS. PPMULr Maa rs*&'801 xi4,(om)Q.rc.r a.,wss o,a,m or&I PMI rou EIIEE 7-M225- o 04/17/96 STORM SEWER SUMMARY REPORT PAGE 1 OF 2 RAYMOND CENTER FILE: 92233C.STM RAINFALL FILE: CHARTI0.RND 25 YEAR DESIGN STORM i = 16.930/ ( Tc + 5.200) ^ 0.792 LINE ID I FLOW RATE INFO I PIPE INFO I HYDRAULIC INFO LINE/j DESCRIPTION JINC ARIRUNOFFCIINLTIMEIINLT IIINC CIAI INPUTQ JUNIFORMISIZE/INVERT IPIPE I NVAL IHGLSLOPEIHYD GRD I VEL DOWNLINEO ITOT ARIWEIGHTD) Tc JTOTL IJTOT CIAI TOTALQ IFLOWCAPITYPE JUP/DOWN ILEN JINVSLOPI JLC JUP/DOWN JUP/DOWN (ac) I C I (sin) l(in/h)l (cfs) I (cfs) I (cfa) l(in) I (ft) l(ft) l(ft/ft)l (ft/ft)l (ft) I (ft/s) 1 I cbl to pond 1 O.01 0.901 0.001 4.591 0.001 0.001 1 24DI 9.141 381 0.0131 0.0011 12.041 2.41 DNLN = O 1 5.41 0.901 15.271 1.551 7.571 7.571 13.81 24DI 9.001 1 0.0041 1.00 1 12.001 2.41 2 cb2 to cbl 1 0.41 0.901 0.001 4.591 1.531 0.001 1 18DI 9.411 721 0.0131 0.0041 12.451 3.97 DNLN = 1 1 5.01 0.901 14.971 1.571 7.021 7.021 6.41 18DI 9.141 1 0.0041 1.00 1 12.131 3.97 1 ( 1 1 1 1 1 1 1 1 1 1 1 1 3 cb3 to cb2 1 0.31 0.901 0.001 4.591 1.401 0.001 1 18DI 10.251 2271 0.0131 0.0021 13.121 2.54 1 DNLN - 2 1 3.01 0.901 13.491 1.671 4.491 4.491 6.41 18DI 9.411 1 0.0041 1.00 1 12.701 2.54 4 1 cb4 to cb3 1 0.61 0.901 0.001 4.591 2.271 0.001 1 18DI 11.021 2071 0.0131 0.0021 13.551 2.40 1 DNLN - 3 1 2.61 0.901 12.041 1.781 4.241 4.241 6.41 18DI 10.251 1 0.0041 1.00 1 13.221 2.40 5 1 cb5 to cb4 1 0.61 0.901 0.001 4.591 2.401 0.001 1 18DI 11.411 1051 0.0131 0.0011 13.761 1.98 1 DNLN = 4 J 2.11 0.901 11.151 1.851 3.501 3.501 6.41 18DI 11.021 1 0.0041 1.00 1 13.641 1.98 1 1 1 1 1 1 1 1 ( 1 1 1 1 1 1 6 1 cb6 to cb5 1 1.01 0.901 0.001 4.591 4.211 0.001 1 18DI 11.851 1181 0.0131 0.0011 13.901 1.53 .1 DNLN = 5 1 1.51 0.901 9.841 1.981 2.711 2.711 6.41 18DI 11.411 1 0.0041 1.00 1 13.821 1.53 1 1 ( 1 1 1 1 1 1 1 ( 1 1 1 1 7 1 cb7 to cb6 1 0.51 0.901 6.301 2.451 1.101 0.001 1 12DI 13.461 3231 0.0131 0.0011 14.291 1.67 1 DNLN - 6 1 0.51 0.901 6.301 2.451 1.101 1.101 2.51 12DI 11.851 1 0.0051 1.00 1 13.941 1.40 8 I CB9 - CB1 1 0.31 0.901 0.001 4.591 1.20I 0.001 1 12DI 11.211 791 0.0131 0.0011 12.181 1.16 1 DNLN - 1 1 0.41 0.901 7.711 2.231 0.911 0.911 5.81 12DI 9.141 1 0.0261 1.00 1 12.131 1.15 9 I cB8 - CB9 1 0.21 0.901 6.301 2.451 0.351 0.001 1 12DI 14.211 1141 0.0131 0.0201 14.541 2.27 1 DNLN - 8 1 0.21 0.901 6.301 2.451 0.351 0.351 5.81 12D] 11.211 1 0.0261 1.00 1 12.201 0.45 10 1 CB10 -CS2 1 0.71 0.901 0.001 4.591 2.811 0.001 1 12DI 10.891 1311 0.0131 0.0071 13.591 3.73 1 DNLN - 2 1 1.61 0.901 9.461 2.021 2.931 2.931 3.81 12DI 9.401 1 0.0111 1.00 1 12.701 3.73 11 1 CB11 - CB10 1 0.31 0.901 0.001 4.591 1.201 0.001 1 12DI 14.201 2931 0.0131 0.0041 14.841 3.49 1 DHLN - 10 1 0.91 0.901 7.811 2.221 1.861 1.861 3.81 12DI 10.891 1 0.0111 1.00 1 13.811 2.37 12 1 CB12 - CB11 1 0.31 0.901 0.001 4.591 1.401 0.001 1 12DI 15.361 1021 0.0131 0.0081 15.851 3.49 1 DNLN a 11 1 0.61 0.901 7.171 2.311 1.331 1.331 3.91 12DI 14.201 1 0.0111 1.00 1 15.031 1.91 13 1 C1313 - CB12 1 0.31 0.901 6.301 2.451 0.661 0.001 1 12DI 16.531 1021 0.0131 0.0091 16.991 2.75 1 DNLN = 12 1 0.31 0.901 6.301 2.451 0.661 0.661 3.81 12DI 15.361 1 0.0111 1.00 1 16.041 1.17 04/17/96 STORM SEWER SUMMARY REPORT PAGE 1 OF 2 RAYMOND CENTER FILE: 92233C.STM RAINFALL FILE: CHARTIO.RND 100 YEAR DESIGN STORM I = 21.753/ ( Tc + 5.600) ^ 0.787 LINE ID I FLAW RATE INFO I PIPE INFO I HYDRAULIC INFO LINE#j DESCRIPTION (INC ARIRUNOFFCIINLTIMEIINLT IIINC CIAI INPUTO IUNIFORMISIZE/IINVERT IPIPE I NVAL IHGLSLOPEIHYD GRD I VEL I DOWNLINE/ ITOT ARIWEIGHTDI Tc ITOTL IITOT CIAI TOTALO IFLOWCAPITYPE IUP/DOWN ILEN IINVSLOPI JLC ]UP/DOWN IUP/DOWN I I (ac) I C I (=in) 1(in/h)1 (Cfs) I (cfs) I (cfs) 1(in) I (ft) 1(ft) I(ft/ft)I (ft/ft)1 (ft) I (ft/s) I I I I I I I I I I I I I I I 1 I cbl to pond I 0.01 0.901 0.001 5.611 0.001 0.001 1 24D1 9.141 381 0.0131 0.0021 12.081 3.34 1 DNLN - 0 1 5.41 0.901 13.341 2.151 10.501 10.501 13.81 24DI 9.001 1 0.0041 1.00 1 12.001 3.34 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 2 1 cb2 to cbl 1 0.41 0.901 0.001 5.611 1.871 0.001 1 18D1 9.411 721 0.0131 0.0091 12.871 5.50 1 DNLN - 1 1 5.01 0.901 13.131 2.171 9.711 9.711 6.41 18D1 9.141 1 0.0041 1.00 1 12.261 5.50 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 3 1 cb3 to cb2 1 0.31 0.901 0.001 5.611 1.721 0.001 1 18D1 10.251 2271 0.0131 0.0031 14.111 3.46 1 DNLN = 2 1 3.01 0.901 12.041 2.281 6.121 6.121 6.41 18DI 9.411 1 0.0041 1.00 1 13.341 3.47 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 4 1 cb4 to cb3 1 0.61 0.901 0.001 5.611 2.781 0.001 1 18DI 11.021 2071 0.0131 0.0031 14.911 3.23 1 DNLN - 3 1 2.61 0.901 10.981 2.391 5.701 5.701 6.41 18DI 10.251 1 0.0041 1.00 1 14.301 3.23 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 5 1 cb5 to cb4 1 0.61 0.901 0.001 5.611 2.931 0.001 1 18D1 11.411 1051 0.0131 0.0021 15.281 2.64 1 DNLN = 4 1 2.11 0.901 10.311 2.471 4.661 4.661 6.41 18D1 11.021 1 0.0041 1.00 1 15.071 2.64 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 6 1 cb6 to cb5 1 1.01 0.901 0.001 5.611 5.151 0.001 1 18D1 11.851 1181 0.0131 0.0011 15.531 2.01 1 DNLN = 5 1 1.51 0.901 9.331 2.591 3.551 3.551 6.41 18D1 11.411 1 0.0041 1.00 1 15.391 2.01 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 7 1 cb7 to cb6 1 0.51 0.901 6.301 3.101 1.401 0.001 1 12D1 13.461 3231 0.0131 0.0021 16.131 1.78 1 DNLN = 6 1 0.51 0.901 6.301 3.101 1.401 1.401 2.51 12D1 11.851 1 0.0051 1.00 1 15.591 1.78 I I I I I I I I I I I I I I 8 I CB9 - CBl 1 0.31 0.901 0.001 5.611 1.461 0.001 1 12D1 11.211 791 0.0131 0.0011 12.341 1.48 1 DNLN - 1 1 0.41 0.901 7.571 2.861 1.161 1.161 5.81 12D1 9.141 1 0.0261 1.00 1 12.261 1.48 I I I I I I I I I I I I 1 I I 9 I CBS - CB9 1 0.21 0.901 6.301 3.101 0.451 0.001 1 12D1 14.211 1141 0.0131 0.0191 14.591 2.44 1 DNLN = 8 1 0.21 0.901 6.301 3.101 0.451 0.451 5.81 12D1 11.211 1 0.0261 1.00 1 12.371 0.57 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 10 1 CB10 -CB2 1 0.71 0.901 0.001 5.611 3.431 0.001 1 12D1 10.891 1311 0.0131 0.0111 14.761 4.70 1 DNLN = 2 1 1.61 0.901 9.691 2.551 3.691 3.691 3.81 12D1 9.401 1 0.0111 1.00 1 13.341 4.70 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 11 CB11 - CB10 1 0.31 0.901 0.001 5.611 1.461 0.001 1 12D1 14.201 2931 0.0131 0.0041 16.361 2.98 1 DNLN - 10 1 0.91 0.901 7.981 2.801 2.341 2.341 3.81 12DI 10.891 1 0.0111 1.00 1 15.101 2.98 I 1 1 1 1 1 1 1 1 1 1 1 1 1 1 12 1 CB12 - CB11 1 0.31 0.901 0.001 5.611 1.721 0.001 I 12D1 15.361 1021 0.0131 0.0021 16.731 2.15 1 DNLN - 11 1 0.61 0.901 7.151 2.941 1.691 1.691 3.81 12D1 14.201 1 0.0111 1.00 1 16.501 2.16 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 13 1 C1313 - CB12 1 0.31 0.901 6.301 3.101 0.841 0.001 1 12DI 16.531 1021 0.0131 0.0021 17.061 2.66 1 DNLN - 12 1 0.31 0.901 6.301 3.101 0.841 0.841 3.81 12D1 15.361 1 0.0111 1.00 1 16.811 1.07 PR.0 FILE Line 1 cb Ito pond 20 (Flj Menu 18 Nntural ground slope 0.53% C) ~ 16 w 14 w HCH- slope O.112�0 12 -- 14 . _.. _.. _.. _.. _.. _.. _.. _.. _.. _.. _.. _.. - - - - - - 38 fi. of 24 in- pipe 0.370% $ 0 5 10 15 20 25 30 35 40 sT-AkTI c)N PRE FILE Lime Z cb2 to cb 1 20 [F1] Menu 1 rz $ Natural ground slope ~ 16 w 14 w _.. _.. _.. _.. _.. _,. _ _HC;Lslope0.447!4 _.. _.. _.. r.. _.. _.. _ - - 12 10 72 fi. of 18 in. pipe 0.970%4 8 0 10 20 30 40 50 60 70 80 sTATI O N FRS FILE 3- Line 3 cb3 to cb2 20 (F1] Menu 18 Natural ground slope O.55 ,o 0 H 14 w 14 HCH- slope 0.183�a 12 228 ft_ of 18 in. pipe (g�3 0.370%o 10 $ 0 50 100 150 200 250 STIALTI o N PR0 FILE Lutes 4 cb4 to cb3 20 [F1] Menu 1$ atuiral pro=d slopes -1.54% r--i 15 w14 HOL slope 0.163% w 12 208 ft. of 18 in. pipe (9) 0.370% 14 $ 0 50 100 150 200 STA.TI�N Line 5 cb5 to cb4 16 [F1] Menu is Z Natural ground slope 0.00% 14 HOOL- slope 0.111�0 w 13 w106 ft. of 18 in. pipe co 0.970�0 12 11 10 0 20 40 60 80 100 120 STATI(D N PR.�FILE Line 6 cb6 to cb5 16 [F1] Menu is zNatural ground slope -O.OS'7. • 14 w 13 118 ft. of 18 in. pipe CS) 0.370�4 w 12 it 10 0 20 40 60 80 100 120 PRCJFIL IE Line 7 cb7 to cb6 • 7'• 1$ [F1] Menu 17 z 16 Natural ground slope ❑.59%e 15 323 ft- of 12 iri. pipe � O.500%b _.. -. w 14 HGL alo w 13 12 11 10 0 50 100 150 200 250 300 350 sTATI O N PR.C�FILE Lines 9 CD8 - CB4 18 (F1] 17 atu n Nral groud slope 0.265Z. Menu 0 16 F--4 15 . - 14 115 ft. of 12 in. pipe 2.61 w 13 r 'HCFL. slope 2. a 12 11 SO 0 20 40 60 80 100 120 STTI�N PRE►FI LE �*� � Line 10 C1310 -cs2 18 [F1] Natural ground slope 0.19% Menu Z 16 0 Q� 14 w 12 92 ft. of 12 in. pipe 1. 1 10 8 0 20 40 60 80 100 120 140 STA.TI�1�T P'R�FILE • 11. Line 11 CB11 - CB10 22 [Flj Menu 20 z Natural Sr ound sl op a 1.0.4 Q i8 16 w293 ft. of 12 in. pipe 1, 1307q.. w HGL al 12 10 8 0 50 100 150 200 250 300 STA.T I 0 N PR.�D FILE 1?� Lins 12 CB 12 - CB 11 21 [F1] Menu 24 Namtural ground slope 0.00% � 19 18 w 17 103 ft. of 12 in. pipe (g) 1. 13O%o w 15 - - -. - iGL slope 0.798 14 13 0 20 40 60 80 100 120 STATION I'RC�FILE •13 Liner 13 C B 13 - C S 12 21 [F1] 1v1 enu 20 Ne�tural ground slope 0.00% 0 19 1--a 18 r� 103 ft. of 12 in. pipe (gam 1. 13070 17 slops 0.92 16 15 . 14 0 20 40 60 80 100 120 STATI C�N