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HomeMy WebLinkAboutSWP272073 2� 73 � EQS IPSME ' COnMSMd TANn1 TS MG pL��llln�l n�l�ln�l� LAND � SNJR N/EYOMG 1 EASTSIDE CONSULTANTS INC• ENGINEERS- 415 RAINIER BLVD. N. ISSAQUAH, WASHINGTON 98027 PHONE[2061 392-5351 FAX [2061 392-4676 SURVEYORS ' DRAINAGE REPORT for ' RENTON CHEVRON ' 9/3/91 t t EASTSIDE CONSULTANTS INC. ENGINEERS- 415 RAINIER BLVD. N. ISSAQUAH,WASHINGTON 98027 PHONE[2061 392-5351 FAX[2061 392-4676 SURVEYORS PROJECT DESCRIPTION: This project consists of an 0. 56 acre parcel located in ' the City of Renton next to the Renton Village Center. Currently, the site is an operating full service Chevron fueling station. The proposed development will consist of ' removing the existing facilities and installing a new fueling station with a convenience store. Planter islands ' are also proposed for the existing parking lot, reducing the ' paved area. The existing site slopes mildly from a high area in the ' center to the east and west with slopes of approximately 0.5% to 2%. The existing ground cover is 95% impervious ' (pavement and roof) with a small graveled area near the ' southeast corner. Runoff from the site currently sheet flows easterly and westerly offsite and is collected in existing catch basins around the perimeter. ' Existing and Proposed Drainage: As stated there is no existing storm drain on-site. ' All existing drainage sheet flows off the site into existing ' storm drain in the surrounding parking lots and roads. No new storm drain is proposed. In addition, the new ' site will have less impervious area than the existing site. Per Core Requirement ,#3 , since the 100 year/24 hour storm ' will increase less than 0. 50 c.f.s. detention will not be trequired. In fact, the 100 year/24 hour storm event runoff will actually decrease for this site. ' No biofiltration for this project is proposed since the paved impervious area for this site will be reduced. 1 1 1 ' CORE REQUIREMENTS #1: Discharge will be as existing into existing storm drain around the site. #2 : The Level 1 Downstream is included. #3 : No runoff control is required since the 100 year/24 hour runoff rate actually decreases. Also, no ' biofiltration is required since no new paving is proposed. Actually the paved area will be reduced to ' install planter islands. #4: Drainage from the site will be sheet flow. Drainage ' under the canopy will be negligible and controlled by ' slotted drain. #5: A TESC plan should not be required. The project merely ' proposes to modify the existing improvements. No new storm drain is proposed and the entire surrounding area ' is paved. ' #6: Applicant will comply as required. #7: Applicant will comply as required. SPECIAL REQUIREMENTS ' #1: Not applicable. #2: Not applicable. ' #3: Not applicable. ' #4 : Not applicable. #5: Not applicable. Note that drainage under the canopy will be directed through an oil/water separator and ' into the sanitary sewer. #6: Not applicable. 1 #7 : Not applicable. ' #8 : Not applicable. #9 : Not applicable. 1 #10: Not applicable. #11: Not applicable. ' #12 : Not applicable. Doxnstream Analysis: All drainage from the site will sheet flow off the site into existing storm drains. The existing storm drain is all ' in the paved drive and parking area for the surrounding ' shopping center and theater. The exact route of drainage is very difficult to follow, but all storm drain pipe ' immediately downstream is 12" diameter with a few 8" ' laterals. Capacity does not appear to be a problem, although during unusually heavy rain storm some parking lot ' ponding may occur. Since the entire area is paved, erosion is not a problem. It is also unlikely that flooding could tdamage any of the buildings since all finish floor appear to ' be high enough above the paving. Approximately 700' south of the site all of the surrounding storm drain discharges into an existing open drainage swale. The swale has been regraded with the recent cinema improvements and is now heavily armored with rip-rap. It is unlikely that erosion will be a problem. This swale flows west before flowing into an existing ' 48" culvert. A new 132" culvert was also installed with the ' I-405 improvements to handle overflow and flooding conditions. The entrance to the 132" culvert is controlled by a weir. These improvements should eliminate any previous ' flooding of the area. These culverts direct drainage under the I-405 ' interchange and discharge into a ditch approximately 1000' ' south. The ditch has been regraded and is heavily armored with rip-rap. Erosion should not be a problem. ' Drainage was followed for more than 1/4 mile. These improvements will actually improve downstream conditions ' since we are reducing discharge from the site. No ' downstream problems appear to exist and none are expected - especially given the new I-405 improvements. m r t♦ LJ SEE SHEET 16 �rvv rim OF t,.ea-N tua-w 1 � tnf�-t ,-{nx+♦ n; PLMA a,K-te ruo-to 4-13 rut+-' tto4-14 lv+i- "1J4W4-4 tl 1 1 tts.u Rtae r . tut.-te tne+- ; . .te �tt}U-t. 'tr... tlb.-. -t p --- ILL ev•-t v.e_1 K6�:..�-'-- nr• ,,.. - i W 1-b b I n _ em-u to ftr5_1 7 T •-- tom+!-� I Kee• � I { 1 rtfir . � n,C ` � 11 , } !I i ru• ,• rug r � ;ul . :t• L I �_ Ittrs et i ! rug-t'r; � o ( rue s , u. — - - Kr,f r T. -•., I _ \\ ` � nay s � � i I I r:/. t Page 1 of 2 King County Building and Land Development Division TECHNICAL INFORMATION REPORT (TIR) WORKSHEET PROJECTPART I OWNER ANG PROJECT LOCATION AND CRIPITION DES PROJECT Pro 1Owner C; u a.4 me Project Na E�� '( a �•1 C 1 Ec/fZ d Address ?o Su' Cat ----.Jav Location Z 3 ' To Phone vmship S Project Engineer Di G�- : fGs rLSection c� Company E r c n r ;'_Co.'C ;C.r,� Project Size 0 • .��O AC ' Address Phone ���• - S i Upstream Drainage Basin Size _AC Q Subdivision Q DORG HPA Q Shoreline Management Q Short Subdivision Q COE 404 Q Rockery Q Grading Q D Darn Safety Q Structural vaunts OE ®.Cornmercial Q FE MA Fa*lain C7 Other Q] other. Q COE wetlands CJ HPA PART 5 SITE 1 COMMUNtTY AND DRAINAGE BA� Commundy Drainage Basin PART 6 SITE CHARACTERISTICS Q River Floodplain Q Stream Q-► watiands 0 Cnftai Stream Reach Q Seeps/Springs 0 Oepressxxw Ci High Groundwater Table Q Lake Q Groundwater Recharge Steep Slopes Q Other �•c ,� �?"s s rn- �` ' Q LakewWErosion Hazard Erosion Potential Erosive Velocities �?ol T hh t��1 D f� " �l� ,q o t,�E , SITE (S �l�vea ' Q Additional Streets Aftwdied 1/90 ' Page 2 of 2 King County Building and Land Development Division ' TECHNICAL INFORMATION REPORT (TIR) WORKSHEET •• • • PARTS REFERENCE LIMITATION/SITE CONSTRAINT r-rt Ch.4-Downstream Analysis C a 0 Additional Streets Attatched ' MM MUM ESC REQUIREMENTS MINIMUM ESC REQUIREMENTS DURING CONSTRUCTION FOLLOWING CONSTRUCTION Sedimentation Facilities Stabilize Exposed Surface Stabilized Construction Entrance Q Remove and Restore Temporary ESC Facilities Perimeter Runoff Control Clean and Remove All Sit and Debris Clearing and Grading Restrictions ® Ensure Operation of Permanent Facilities ' [J Caller Practices Flag limits of NGPES G Construction Sequence Other ' other C. ' = Grass Lined Channel 0 Tank Infftbon Method of Analysis a Pope System 0 Vault 0Depreswri 1, Open Channel = Energy Dissapator 0 Flow Dom" Cornpensation/lilitigation Dry Pond = Welland = Waiver of Eliminated Site Storage Wet Pond 0 Stream Regional Detention ' Brief Description of System Operation S Facility Related Site Limitations Additional Sheets Attatched ' Reference Facility Limtation PART 11 STRUCTURAL ANALYSIS PART 12 EASE,'JENTS,TRACTS 1 require • IJ Drainage Easement Cast in Place Vault C'i Other Access Est _ Remning Wall Native Growth Protection Easement ' Rockery>4'High Tract _ Structural on Steep Slope Offer ' PART 14 SIGNATURE OF - • • or a ovii engineer under my supervision have visited the site. Actual site conditions as observed were incorporated into this worksheet and the me y attatcnments. To the best of my knowledge the information provided here is accurate_ 1/90 1 i 1 ' �� C �6!�o�✓ -� dG �ia✓v� '�L.G J�Z .t "'lC vC �oPea� too q2�c �1 l�ri.� 7 u 1 1 �xrst1A1G OIL 4T Pe�,��s �. 'Flc 1 �Pyel� i7 '`�t 1A- V/,0 �r Q��. l lee Y✓G - d. 0� c c 3ASI:l ID: WE100 NAME: WEST EXISTING 100 'CE?R ' SB(TH KETHODOLCGY TOTAL AREA. . . . . . . : 0 . 31 Acres 3ASEFL0WS: 0 . 00 cfs RAINFALL TYPE. . . . : USER1 PERVIOUS AREA ' PRECIPITATION. . . . : 3 .90 inches AREA. . : 0. 00 Acres TIME INTERVAL. . . . : i0 . 00 min CN. . . . : 39 . 00 TIME OF CONC. . . . . : 1. 34 min IMPERVIOUS AREA ' ABSTRACTION COEFF: 0 . 20 AREA. . : 0 . 31 Acres CN. . . . : 98 . 00 TcReach - Sheet L: 30. 00 ns: 0 . 0110 p2yr: 2 . 00 3: 0 . 0130 PEAK RATE: 0 . 37 cfs VOL: 0. 09 Ac-ft TIME: 470 min ' BASIN ID: WD100 NAME: WEST DEVELOPED 100 YEAR ' SBUH M=ODOLOGY TOTAL AREA. . . . ' • 0.28 Acres BASEFLOWS: 0.00 cfs RAINFALL TYPE. . . . : USER1 PERVIOUS AREA PRECIPITATION. . . . : 3 .90 inches AREA. . : 0.02 Acres TIME INTERVAL. . . . : 10.00 m111 CN. . . . : 86.00 TIME OF CONC. . . . . : 0.96 min IMPERVIOUS AREA ABSTRACTION COEFF: 0.20 AREA. . : 0.26 Acres CN. . . . : 98.00 TcReach - Sheet L: 65.00 ns:0.0110 p2yr: 2.00 s:0.0270 PEAK RATE: 0.33 cfs VOL: 0.08 Ac-ft TIME: 470 min ' BASIN ID: EE100 NAME: EAST EXISTING 100 YEAR SBUH METHODOLOGY TOTAL AREA. . . . . . . : 0.25 Acres BASEFLOWS: 0.00 cfs ' RAINFALL TYPE. . . . : USER1 PERVIOUS AREA PRECIPITATION. . . . : 3 .90 inches AREA. . : 0.03 Acres TIME INTERVAL. . . . : 10.00 min CN. . . . : 89.00 ' TIME OF CONC. . . . . : 1.50 min IMPERVIOUS AREA ABSTRACTION COEFF: 0.20 AREA. . : 0.22 Acres CN. . . . . 98.00 'TcReach - Sheet L: 90.00 ns:0 .0110 p2yr: 2 .00 s:0. 0170 PEAK RATE: 0. 29 cfs VOL: 0. 07 Ac-ft TIME: 470 min 1 BASIN ID: ED100 NAME: EAST DEVELOPED 100 ':yAR SBUH '4ETHODOLOGY - -- - ' TOTAL AREA. . . . . . . : 0. 28 Acres BASEFLOWS: ) . JO cfs RAINFALL TYPE. . . . : USER1 PERVIOUS AREA PRECIPITATION. . . . : 3 .90 inches AREA. . : J . 04 Acres TT_ME INTERVAL i0. 00 min CN. . . . : 36 . 00 TIME OF CONC. . . . . . 1. 20 min IMPERVIOUS AREA ABSTRACTION COEFF: 0 . 20 AREA. . . J .24 Acres ON. . . . . ?8 . 10 TcReach - Sheet L: 70 . 00 ns: 0 . 0110 :;2yr: 2 . JJ 5: 0 . 0180 PEAK RATE: 0 . 32 cfs '.OL: 0 . 08 Ac-=t TI'ME: 470 min rb P- S 1 r1 I2I 31 I 14 ! � C ' 7 t !a ° Hyd No. 1 WE 100 10 Hyd No. Z .. W pioo 12 (� 13 14 13r: 16 U o 17 !f 1° 20 21 , 22 4 26 2' N 16U TM, PILVI.-,o Poles Q.3 27 �2A I2°1 1I301 �311 32 331 3 6 9 12 15 18 2I 24 27 ' � Tim in Hours 37 1 I �3Vj Hyd No m 1 40I Rates 0.37 c s Times 7.93 hr 41 Vol 0.09 Ac—ft Int: 10.00 min 421 Hyd No. : 2 431 Rates O.ZZ c sTime: 7.8.3 hr Vol 0.08 Ac—ft Int: 10.00 min 45i 4gl 371 501 51, 521 531 54- 56t S?: 2 3 4 l• S ! Q I - r Lr�Tn el 9� 10� HW No. 4.. ''2 i r I13 !17 20 ,21 uj Q IDo �#- Drr,Yiew PEn= 0 31- G� �1 6I `� f tom.-[t,�1.6� = Q,l•`t G .-1 28, 301 301 311 32i i331 34 35) 3 6 9 12 15 18 21 24 2't 361 Tip& in Hours 371'3 ' 3°f Hvd No. s 3 401 Rate: 0.29 cfs Times 7.83 hr 411 Vol 0.07 Ac-ft Int: 10.00 min 421 N Hyd No. : 4 i31 Rate: 0.32 cfs Time: 7.83 hr '"' Vol 0.08 Ac-ft Int: 10.00 min A51 461 471 481 49f - 501 51; 51 531 Shc S6f i pfq GO r - .•,�,. 1 � -T•hie , 'e �� -��i.taw �M b .► 1 �+ 1 I � 1 I FAl; ._u 1 1 x 1 PAVED TLVM Do a.eas 1 , it OraMsr M 11 l� PVCIs !r l 30 1 O.o Doan MON ar■. �. l , / I L UZI"M. I 1 N I --t !Xsawm I u SOUTH GRAbr WAY /VlA P .r.• � I stiff t—j err 1 sit 1---I R,z lam,, 04 r , n tus r wr all J , J a..,..,..n A i r i as J� i h�� o r �a R ► � I J ' • J II --Ya&1D�- —n..rr.na. I _ I,NOW vrs e-VI. riwaow� O/,.w w ��01�• SOUTH GRAOY `WAY 10..71H wneA 10 wM1 ��� sTij�Si 8ASl0 / Vj -- 3/ 19/91 Eastside Consultants page 1 RENTON CHEVRON STATION BASIN SUMMARY BASIN ID: EE10 NAME: EAST EXISTING 10 YEAR ' SBUH METHODOLOGY TOTAL AREA. . . . . . . : 0. 25 Acres BASEFLOWS: 0 . 00 cfs RAINFALL TYPE. . . . : USER1 PERVIOUS AREA PRECIPITATION. . . . : 2 .90 inches AREA. . : 0 . 03 Acres TIME INTERVAL. . . . : 10. 00 min CN. . . . : 89 . 00 TIME OF CONC. . . . . : 1. 50 min IMPERVIOUS AREA ABSTRACTION COEFF: 0. 20 AREA. . : 0. 22 Acres CN. . . . : 98 . 00 TcReach - Sheet L: 90. 00 ns:0. 0110 p2yr: 2 . 00 s: 0 . 0170 PEAK RATE: 0. 21 cfs VOL: 0.05 Ac-ft TIME: 470 min ' BASIN ID: EE100 NAME: EAST EXISTING 100 YEAR SBUH METHODOLOGY TOTAL AREA. . . . . . . : 0. 25 Acres BASEFLOWS: 0. 00 cfs ' RAINFALL TYPE. . . . : USER1 PERVIOUS AREA PRECIPITATION. . . . : 3 .90 inches AREA. . : 0. 03 Acres TIME INTERVAL. . . . : 10. 00 min CN. . . . : 89 . 00 ' TIME OF CONC. . . . . : 1.50 min IMPERVIOUS AREA ABSTRACTION COEFF: 0. 20 AREA. . : 0. 22 Acres CN. . . . . 98 . 00 ' TcReach - Sheet L: 90. 00 ns:0. 0110 p2yr: 2 . 00 s: 0. 0170 PEAK RATE: 0.29 cfs VOL: 0.07 Ac-ft TIME: 470 min t BASIN ID: EE2 NAME: EAST EXISTING 2 YEAR ' SBUH METHODOLOGY TOTAL AREA. . . . . . . : 0.25 Acres BASEFLOWS: 0. 00 cfs RAINFALL TYPE. . . . : USER1 PERVIOUS AREA PRECIPITATION. . . . : 2 . 00 inches AREA. . : 0. 03 Acres TIME INTERVAL. . . . : 10.00 min CN. . . . : 89 . 00 TIME OF CONC. . . . . : 1. 50 min IMPERVIOUS AREA ' ABSTRACTION COEFF: 0.20 AREA. . : 0. 22 Acres CN. . . . : 98 . 00 TcReach - Sheet L: 90. 00 ns. 0 . 0110 p2yr. 2 . 00 s: 0 . 0170 PEAK RATE: 0. 14 cfs VOL: 0. 04 Ac-ft TIME: 470 min 8/19/91 Eastside Consultants page 2 ' ------------------=====RENTON-CHEVRON-STATION =====___________________ --------------- BASIN SUMMARY BASIN ID: EE25 NAME: EAST EXISTING 25 YEAR ' SBUH METHODOLOGY TOTAL AREA. . . . . . . : 0. 25 Acres BASEFLOWS: 0. 00 cfs RAINFALL TYPE. . . . : USER1 PERVIOUS AREA PRECIPITATION. . . . : 3 . 40 inches AREA. . : 0. 03 Acres ' TIME INTERVAL. . . . : 10. 00 min CN. . . . : 89 .00 TIME OF CONC. . . . . : 1.50 min IMPERVIOUS AREA ABSTRACTION COEFF: 0.20 AREA. . : 0.22 Acres CN. . . . : 98. 00 TcReach - Sheet L: 90. 00 ns:0. 0110 p2yr: 2 . 00 s:0. 0170 PEAR RATE: 0.25 cfs VOL: 0. 06 Ac-ft TIME: 470 min 1 8/ 19/91 Eastside Consultants page 1 RENTON CHEVRON STATION BASIN SUMMARY BASIN ID: WE10 NAME: WEST EXISTING 10 YEAR SBUH METHODOLOGY TOTAL AREA. . . . . . . : 0 . 31 Acres BASEFLOWS: 0. 00 cfs RAINFALL TYPE. . . . : USER1 PERVIOUS AREA PRECIPITATION. . . . : 2 . 90 inches AREA. . : 0. 00 Acres ' TIME INTERVAL. . . . : 10. 00 min CN. . . . : 89 . 00 TIME OF CONC. . . . . : 1. 34 min IMPERVIOUS AREA ABSTRACTION COEFF: 0. 20 AREA. . : 0. 31 Acres ' CN. . . . : 98 . 00 TcReach - Sheet L: 80. 00 ns:0. 0110 p2yr: 2 . 00 s:0. 0180 PEAK RATE: 0.27 cfs VOL: 0.07 Ac-ft TIME: 470 min ' l BASIN ID: WE100 NAME: WEST EXISTING 100 YEAR SBUH METHODOLOGY __-- TOTAL AREA. . . . . . . : 0. 31 Acres BASEFLOWS: 0. 00 cfs ' RAINFALL TYPE. . . . : USER1 PERVIOUS AREA PRECIPITATION. . . . : 3 . 90 inches AREA. . : 0.00 Acres TIME INTERVAL. . . . : 10. 00 min CN. . . . : 89. 00 TIME OF CONC. . . . . : 1. 34 min IMPERVIOUS AREA ABSTRACTION COEFF: 0 .20 AREA. . : 0.31 Acres CN. . . . . 98. 00 ' TcReach - Sheet L: 80. 00 ns:0. 0110 p2yr: 2 . 00 s:0. 0180 PEAK RATE: 0.37 cfs VOL: 0.09 Ac-ft TIME: 470 min BASIN ID: WE2 NAME: WEST EXISTING 2 YEAR ' SBUH METHODOLOGY TOTAL AREA. . . . . . . : 0. 31 Acres BASEFLOWS: 0.00 cfs RAINFALL TYPE. . . . : USER1 PERVIOUS AREA PRECIPITATION. . . . : 2 . 00 inches AREA. . : 0. 00 Acres TIME INTERVAL. . . . : 10. 00 min CN. . . . : 89. 00 TIME OF CONC. . . . . : 1. 34 min IMPERVIOUS AREA ABSTRACTION COEFF: 0. 20 AREA. . : 0. 31 Acres CN. . . . : 98. 00 TcReach - Sheet L: 80. 00 ns. 0. 0110 p2yr. 2 . 00 s: 0. 0180 PEAK RATE: 0 . 19 cfs VOL: 0. 05 Ac-ft TIME: 470 min 8/19/91 Eastside Consultants page 2 - RENTON-CHEVRON STATION BASIN SUMMARY BASIN ID: WE25 NAME: WEST EXISTING 25 YEAR SBUH METHODOLOGY ' TOTAL AREA. . . . . . . : 0. 31 Acres BASEFLOWS: 0. 00 cfs RAINFALL TYPE. . . . : USER1 PERVIOUS AREA PRECIPITATION. . . . : 3 . 40 inches AREA. . : 0. 00 Acres TIME INTERVAL. . . . : 10. 00 min CN. . . . : 89. 00 TIME OF CONC. . . . . : 1. 34 min IMPERVIOUS AREA ABSTRACTION COEFF: 0.20 AREA. . : 0.31 Acres CN. . . . : 98 .00 TcReach - Sheet L: 80. 00 ns:0. 0110 p2yr: 2 . 00 s:0. 0180 PEAK RATE: 0. 32 cfs VOL: 0. 08 Ac-ft TIME: 470 min ' 8 19 91 Eastside Consultants page 1 RENTON CHEVRON STATION ' BASIN SUMMARY=====_______________________ BASIN ID: ED10 NAME: EAST DEVELOPED 10 YEAR SBUH METHODOLOGY TOTAL AREA. . . . . . . : 0 . 28 Acres BASEFLOWS: 0 . 00 cfs RAINFALL TYPE. . . . : USER1 PERVIOUS AREA PRECIPITATION. . . . : 2 . 90 inches AREA. . : 0 . 04 Acres TIME INTERVAL. . . . : 10. 00 min CN. . . . : 86. 00 ' TIME OF CONC. . . . . : 1. 20 min IMPERVIOUS AREA ABSTRACTION COEFF: 0.20 AREA. . : 0 . 24 Acres CN. . . . . 98 . 00 TcReach - Sheet L: 70. 00 ns: 0. 0110 p2yr: 2 . 00 s: 0. 0180 PEAK RATE: 0.23 cfs VOL: 0.06 Ac-ft TIME: 470 min BASIN ID: ED100 NAME: EAST DEVELOPED 100 YEAR SBUH METHODOLOGY - - - ------ TOTAL AREA. . . . . . . : 0.28 Acres BASEFLOWS: 0. 00 cfs RAINFALL TYPE. . . . : USER1 PERVIOUS AREA ' PRECIPITATION. . . . : 3 . 90 inches AREA. . : 0. 04 Acres TIME INTERVAL. . . . : 10.00 min CN. . . . : 86. 00 TIME OF CONC. . . . . : 1.20 min IMPERVIOUS AREA j ABSTRACTION COEFF: 0. 20 AREA. . : 0. 24 Acres CN. . . . . 98 . 00 TcReach - Sheet L: 70. 00 ns:0. 0110 p2yr: 2 . 00 s: 0. 0180 ' PEAK RATE: 0. 32 cfs VOL: 0.08 Ac-ft TIME: 470 min BASIN ID: ED2 NAME: EAST DEVELOPED 2 YEAR SBUH METHODOLOGY TOTAL AREA. . . . . . . : 0.28 Acres BASEFLOWS: 0. 00 cfs RAINFALL TYPE. . . . : USER1 PERVIOUS AREA PRECIPITATION. . . . : 2 .00 inches AREA. . : 0. 04 Acres TIME INTERVAL. . . . : 10.00 min CN. . . . : 86. 00 TIME OF CONC. . . . . : 1.20 min IMPERVIOUS AREA ABSTRACTION COEFF: 0.20 AREA. . : 0.24 Acres CN. . . . : 98 . 00 TcReach - Sheet L: 70. 00 ns:0. 0110 p2yr: 2 . 00 s: 0 . 0180 PEAK RATE: 0. 15 cfs VOL: 0. 04 Ac-ft TIME: 470 min 8/19/91 Eastside Consultants page 2 RENTON-CHEVRON-STATION ==_==___________________ BASIN SUMMARY BASIN ID: ED25 NAME: EAST DEVELOPED 25 YEAR ' SBUH METHODOLOGY TOTAL AREA. . . . . . . : 0. 28 Acres BASEFLOWS: 0. 00 cfs RAINFALL TYPE. . . . : USER1 PERVIOUS AREA PRECIPITATION. . . . : 3 .40 inches AREA. . : 0. 04 Acres ' TIME INTERVAL. . . . : 10. 00 min CN. . . . : 86. 00 TIME OF CONC. . . . . : 1.20 min IMPERVIOUS AREA ABSTRACTION COEFF: 0.20 AREA. . : 0. 24 Acres ' CN. . . . : 98. 00 TcReach - Sheet L: 70. 00 ns:0. 0110 p2yr: 2 . 00 s: 0. 0180 PEAK RATE: 0.28 cfs VOL: 0. 07 Ac-ft TIME: 470 min 8/19/91 Eastside Consultants page 1 RENTON CHEVRON STATION BASIN SUMMARY BASIN ID: WD10 NAME: WEST DEVELOPED 10 YEAR ' SBUH METHODOLOGY TOTAL AREA. . . . . . . : 0. 28 Acres BASEFLOWS: 0. 00 cfs RAINFALL TYPE. . . . : USER1 PERVIOUS AREA ' PRECIPITATION. . . . : 2 . 90 inches AREA. . : 0. 02 Acres TIME INTERVAL. . . . : 10 . 00 min CN. . . . : 86. 00 TIME OF CONC. . . . . : 0. 96 min IMPERVIOUS AREA ABSTRACTION COEFF: 0 .20 AREA. . : 0.26 Acres ' CN. . . . : 98 . 00 TcReach - Sheet L: 65. 00 ns: 0. 0110 p2yr: 2 . 00 s:0. 0270 PEAK RATE: 0. 24 cfs VOL: 0. 06 Ac-ft TIME: 470 min ' BASIN ID: WD100 NAME: WEST DEVELOPED 100 YEAR SBUH METHODOLOGY TOTAL AREA. . . . . . . : 0.28 Acres BASEFLOWS: 0. 00 cfs ' RAINFALL TYPE. . . . : USER1 PERVIOUS AREA PRECIPITATION. . . . : 3 .90 inches AREA. . : 0. 02 Acres TIME INTERVAL. . . . : 10. 00 min CN. . . . : 86. 00 ' TIME OF CONC. . . . . : 0.96 min IMPERVIOUS AREA ABSTRACTION COEFF: 0. 20 AREA. . : 0.26 Acres CN. . . . . 98 .00 TcReach - Sheet L: 65. 00 ns:0. 0110 p2yr: 2 . 00 s:0 . 0270 PEAK RATE: 0. 33 cfs VOL: 0. 08 Ac-ft TIME: 470 min BASIN ID: WD2 NAME: WEST DEVELOPED 2 YEAR ' SBUH METHODOLOGY TOTAL AREA. . . . . . . : 0.28 Acres BASEFLOWS: 0. 00 cfs RAINFALL TYPE. . . . : USER1 PERVIOUS AREA ' PRECIPITATION. . . . : 2 .00 inches AREA. . : 0. 02 Acres TIME INTERVAL. . . . : 10. 00 min CN. . . . : 86. 00 TIME OF CONC. . . . . : 0.96 min IMPERVIOUS AREA ' ABSTRACTION COEFF: 0. 20 AREA. . : 0.26 Acres CN. . . • 98 . 00 TcReach - Sheet L: 65. 00 ns:0. 0110 p2yr: 2 . 00 s: 0 . 0270 PEAK RATE: 0 . 16 cfs VOL: 0. 04 Ac-ft TIME: 470 min 8/19/91 Eastside Consultants page 2 -------------RENTON-CHEVRON-STATION ---_-_--________ BASIN SUMMARY BASIN ID: WD25 NAME: WEST DEVELOPED 25 YEAR ' SBUH METHODOLOGY TOTAL AREA. . . . . . . : 0. 28 Acres BASEFLOWS: 0. 00 cfs RAINFALL TYPE. . . . : USER1 PERVIOUS AREA PRECIPITATION. . . . : 3 . 40 inches AREA. . : 0. 02 Acres ' TIME INTERVAL. . . . : 10. 00 min CN. . . . : 86 . 00 TIME OF CONC. . . . . : 0.96 min IMPERVIOUS AREA ABSTRACTION COEFF: 0. 20 AREA. . : 0.26 Acres ' CN. . . . : 98 . 00 TcReach - Sheet L: 65. 00 ns: 0. 0110 p2yr: 2 . 00 s:0. 0270 PEAK RATE: 0. 29 cfs VOL: 0. 07 Ac-ft TIME: 470 min 1 1