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2006 Drainage Calcs.pdfRESUB AUG 2 3 2006 BUILDING DEPARTMENT CITY OF EDMONDS Drainage Calculations FOR: Norton Residence 806 Cary Road Edmonds, WA 98020 G[Ji F, EXPIRES 9/5/ Prepared by: Julie Sandoz, E.I.T. CG Engineering PLLC August 22, 2006 CG Engineering Project No. 06094.20 PROJECT OVERVIEW: The project is located at 806 Cary Road in Edmonds, Washington. The project site consists of a trapezoidal shaped parcel encompassing approximately 1. 0 1 acres. Development on site will consist of construction of a new single-family residence. A vicinity map and photographs are included in Appendix A. EXISTING CONDITIONS: The existing project site is currently occupied by a single-family residence which is to remain. The site drains to the east with an average slope of approximately 6.25 percent towards Shell Creek. There is not an existing storm drainage system located in Cary Road. There is not an existing detention system on site. All runoff is currently exiting the site via sheet flow to the east and entering Shell Creek which flows to the north near the eastern property line. The pre - developed flow rates for the 2-year, 1 0-year, and 1 00-year 24-hour storms are 0. 07, 0.14 and 0.32 cfs respectively. DEVELOPED CONDITIONS: The developed site will consist of a one-story single-family residence, which has a footprint of approximately 0. 148 acres. The site is modeled with one basin, where storm water runoff is generated mostly from the lawn areas and residences. Storm water runoff from these areas will be captured and drained into a 4-foot diameter detention pipe located to the north of the proposed residence. The runoff will pass through a flow control structure that will detain the developed flows and limit the peak rate of runoff to 50 percent of the pre -developed condition 2-year, 24- hour design storm, while maintaining the pre -developed condition peak runoff rate for the 10- year, 24-hour and 100-year, 24-hour storms. See Appendix B for sizing calculations. After the storm water has passed through the flow control structure, it will drain to a proposed dispersion trench and will exit the site to the east via sheet flow towards Shell Creek Other quality control requirements as specified in ECDC 18.30.060.B are as follows. #2: Preservation of Natural Drainage Systems The existing storm water currently drains via sheet flow to the east towards Shell Creek. After development is completed storm water will be released from the detention tank and overflow the dispersion trench and drain in its natural flow path towards Shell Creek. #3: Source Control of Pollution: Storm water being detained is from the roof, pavement and landscaped areas, where pollution sources are not very common. The main source for pollutants may come from the new catch basin that is to be installed in the existing asphalt driveway. A turned down "tee" will be installed to minimize the amount of oils and greases entering the detention tank. #4: Runoff Treatment BMPs: Only 3, 100 square feet of pavement is contributing runoff to the detention system and is considered to be insignificant. #5: Wetlands: There is an existing wetland near the eastern property line. Storm water is discharged per City of Edmonds Development Code 18.30.060 1-b. There are no proposed structures or drainage facilities within the wetland. All storm water on -site entering the wetland will enter via sheet flow. There is an existing 6" diameter storm drain that appears to be contributing runoff to the wetland from the neighboring properties to north and the south. #6: Water Quality Sensitive Areas: Shell Creek is located near the eastern property line. The amount of pollution generating impervious surfacing is considered negligible. The minimum requirements have provided adequate protection of the water quality sensitive area. #7: Off -Site Analysis and Mitigation: Existing storm water from this site is currently exiting the site via sheet flow to the east and entering Shell Creek which flows to the north near the eastern property line. The proposed development should not increase sedimentation and stream bank erosion, or violate water quality standards. #8: Basin Planning: The project is modeled with one basin and is located in the Shell Creek Basin. #9: Operation and Maintenance: Operation and Maintenance will be the responsibility of the owner. #10: Financial Liability: Required performance bonds will be provided as necessary. EROSION AND SEDIMENT CONTROL: Clearing limits are delineated on the final engineering plans and will be flagged in the field prior to the start of construction. A filter fabric fence will be installed around the entire downhill perimeter of the site along the property lines. The filter fabric fence will be checked periodically during the wet season. It will be inspected during and after any heavy rainfall. Damage will be repaired prior to leaving the site. The fence shall be removed within 30 days after the site has been stabilized. Any disturbed areas resulting from construction or removal of the erosion control measure shall be stabilized. If possible, the clearing and land alteration work will be scheduled in the dry season. Trapped sediment will be removed or stabilized on site. The existing gravel driveway will be used as a construction entrance prior to any clearing for the new single-family residence to minimize truck tire soil tracking. If construction vehicles transport soil and/or debris onto road surfaces, the roads shall be cleaned thoroughly at the end of the day. Sediment shall be removed by shoveling and sweeping and transported to a controlled sediment disposal area. Street washing shall be allowed only after sediment is removed in this manner. APPENDIX A loom Not 14 Pu at Dr puga sp .9 > Hin to- --*Y 4�4 lit O!ooftem Dr CaRm iz caspem st LA !VIM IA -pi Aloha Wa Aloha St cuolway z Glen st Vicinitv Ma Norton Residence CG Engineering Project # 06094.20 May 22, 2006 Page 1 Photo 1: Existing house & driveway Photo 2: Existing gravel/grass driveway -Phato-3: - Looking west Norton Residence May 22, 2006 CG Engineering Project # 06094.20 Page I Photo 4: Looking south Photo 5: Existing building to be removed and lawn. Looking northwest APPENDIX B Detention Volume Calculation Worksheet for Norton Residence in Edmonds, WA Basis for the design on the DOE Standards for Detention of matching of the existing 1/22yr., I Oyr. & I 00-yr. storm release rates. Use King County HYD program for Detention Calculations Soil Type: Alderwood Type — 46C5� Total Area: 1. 0 1 acres Predevelopment : Pervious Area = 0.946 acres with CN = 85 Impervious Area = 0.064 acres with CN = 98 Travel Time (Tt) = 24 min. Pro -posed development : Pervious Area = 0.862 acres with CN = 86 Impervious Area = 0. 148 acres witli CN = 98 Travel Time (Tt) = 10 min. Storm for Area: 24 hour Type IA (Edmonds, WA) ,)-Vr I 0-Vr. I 00--Nr. ±:L-- 1.5 in. 2.0 in. 3.0 in. Calculated Storms Volumes for Norton Residence Storm Predeveloped Developed (cfs) Target (cfs) Actual (cfs) PK Stageft) Volume (cli. ft.) 2-year 0.07 0.13 0.035 0.04 2.14 400 1 0-year 0.14 0.23 0.14 0.15 2.45 480 1 00-year 0.32 0.45 0.32 0.32 3.99 740 Orifice: Bottom: 0.80 inches @ H = 0.00 ft Top: 2.76 inches @ H = 2. 10 ft Required Storage = 749 Cu. Ft. Provided Length of pipe = 57 Lin. Ft. Volume provided by 48" Diameter pipe = 715 Cu. Ft Volume provided in 4.35' C.B. = 50 Cu. Ft. Volumne provided in 2' transfer pipe = 6 ft Volume provided in Pipe and C.B. = 771 Cu. Ft. --City of Edmonds CG # 06094.20 -- -- - ---------- -- ----- --- -- -- ---------- - -- --- ------- (Do wo TO T(4 L A-V--C A- N��y S co" D % T-I 0 C--e-�j 1 0 c, C-Y- t S =T,4— &S, 6 tqC JcC� ex I ST-� �->U 4� �-�x -2-eow G CA-,, C- I A& P&r,-v 1 0 0 S -T TO T-;Ot-L- Fe 9- v 10 u's 5ue-F-A� Ow I- tv\, IO+f9O A C-e-c- 21 P2 P 2-� 0 110 PI CO 3,0 4= Description A, Ai 0 (+c, C- CALL's. 0 L Checked Date 0 ENGINrECERING Scale Sheet No. 250 4th Ave. South ProJect C) IZ-V -Ij yt�5- Job No. Suite 200 Edmon&, WA 98020 0 1,0 STORMWATZR MANAGE24ENT MANUAL FOR THE PUGET SOUND BASIN Table 111-1.4 -n" AND "k" Values Used in Time Calculations for HydrOgraphs "n," Sheet Flow Equation Manning's Values (for the initial 300 ft. of travel) n, Smooth surTa-ce-s concrete, asphaic, gr4ve-L, or bare hand packed sail) 0.011 Fallow fields or loose soil surface (no residue) Cultivated soil with residue 0.0s cover (3:5 0.20 ft/ft) Cultivated soil with residue cover (8> 0.20 ft/ft) 0.06 Short pr&Jxla grass and lawns 0.17 Dense grasses 0-15 Bermuda grass 19-p- Range (natural) Woods or forest with light underbrush 0.13 Woods or forest with dense underbrush 0.40 0.80 -manning values for iK`eQt flow only, from Overton and Meadows l976_(S_e_,9_T_R-_55_,-j_q-86) "k" Values Used in Travel Time/Time of Concentration Calculations Shallow Concentrated Flow (After the initial 300 ft. of sheet flow, R = 0.1) k, 1. Forest with 'Seavy ground litter and meadows (n = 0.1o) 2. Brushy 3 ground with some trees (n = 0.060) 3. Fallow or minimum tillage cultivation (n = 0.040) 4. High 5 a grass (n = 0.035) S. Short grass, pasture and lawns (n = 0.030) 6. 9 Nearly bare ground (a = 0.25) 11 7. Paved and gravel areas (n = 0.012) 13 27 Channel Flow (intermittent) (At the beginning of visible channels R = 0.2) ka 1. Forested GwT18 with heavy ground 1-itter (n = 0.10) 2. Forested drainage course/ravine with defined channel bed (n = o.oso) io 3. Rack -lined waterway (n - 0.03S) 4. Grassed waterway (n - 0.03o) is S. Earth -lined waterway (n - 0.02s) 17 6. CXP pipe (n - 0.024) 20 7. Concrete pipe (0.012) 21 8- Other waterways and Pipe O-SC8/n 42 Channel Flow (Continuous stream, R = 0.4) k. 1 9. 10. Meand-ering stream with Rock -lined some pools (n = 0 .040) 0 stream (n 0.035) 11. Grass -lined stream (n 0.030) 23 12. Other streams, man-made channels and pipe 0.807/n* 27 171-1 -7 6 FEBRUARY, 1992 STORMWATER. MANAGEMENT MANUAL FOR THE PUGET SOUND BASIN Table 111-1.3 SCS western Washington Runoff Curve Numbers (Published by SCS in 1982) Runoff curve numbers for selected agricultural, suburban and urban 1 areq ii asa fny- 'rlrns- I ik �m ; _-P� 1 1 A ; .4. — ' '1­+- 4 __ I A—$-- A LAND USE DESCRIPTION CURVE NUMBERS BY HYD ROLOGIC SOIL GROUP A B C D Cultivated land(l): winter condition 86 91 — 94 95 Mountain open areas: low growing brush Q grasslands 74 82 89--, 92 Meadow or pasture: 65 78 89 Wood or forest land:. undisturbed 42 64 76 81 Wood or forest land: young second growth or brush ss 72 81 86 Orchard: with cover crop - 81 88 92 94 Open spaces, lawns, parks, golf courses, cemeteries, landscaping. Good condition: grass cover an �:7S% of the 68 80 90 (0) area Fair condition: grass cover on 50-75% of 77 85 90 92 the area Gravel roads a parking lots: 76 as 89 91 D�Jrrt roads & parking lots: 72 82 a7__ 89 Impervious surfaces, pavement, roofs etc. 98 98 (2w 98 Oren water bodies: lakes, wetlands, ponds etc- 100 100 100 100 Single family residential(2): Dwelling Unit/Gross Acre %Impervlous(3) Separate curve number 1-0 DU/GA is shall be selected for 1.5 DU/GA 20 pervious & impervious 2.0 DU/GA 25 portions of the site 2.5 DU/GA 30 or basin 3.0 DU/GA 34 3.5 DU/GA 38 4.0 DU/GA 42 4.5 DU/GA 46 5.0 DU/GA 48 5.5 DU`/GA so 6.0 DTJ/GA S2 6.S DU/GA 54 7.0 DU/GA 56 PUD's, condos, apartments, %impervious commercial businesses must be industrial areas- computed (1) For a more detailed description of agricultural land use curve numbers refe= to National Engineering Handbook, Sec. 4, Hydrology, Chapter 9, August 1972- (2) Assumes roof and driveway runoff is directed into street/storm systam. (3) The remaining pervious areas (lawn) are considered to be in good condition for these curve numbers. 111-1-12 FEBRU;�RY, 1992- Time of Concentration ( T, EAsting Conditions for: Edmonds, WA Sheet Flow Sezment 1 (For the initial 300 feet) L = 230 ft N, = 0.24 Lawn P2 = 1.50 in 2-year so = 0.074 ft/ft Tt = 24.09 niin Shallow Concentrated Flow Seginent 2 (After the initial 300 feet) L 0 ft K 3 Wooded so 0.032 ft/ft Vo 0.53 ft / see Tt 0.00 min Total 24.09 min Use 24.00 min Time of Concentration By ims DWa 7/19/2006 0 ChU Daic ENGINEeRING Existing Conditions Shcallo. 250 4th Ave. South N.T.S. Suite 200 lob Nm Edmonds, WA 98020 FNorton Residence 06094.20 Nortonreport.txt KING COUNTY DEPARTMENT OF PUBLIC WORKS surface water management DiVision HYDROGRAPH PROGRAMS Version 4.21B 1 - INFO ON THIS PROGRAM 2 - SBUHYD 3 - MODIFIED SBUHYD 4 - ROUTE 5 - ROUTE2 6 - ADDHYD 7 - BASEFLOW 8 - PLOTHYD 9 - DATA 10 - RDFAC 11 - RETURN TO DOS ENTER OPTION: SBUH/SCS METHOD FOR COMPUTING RUNOFF HYDROGRAPH STORM OPTIONS: 1 - S.C.S. TYPE-lA 2 - 7-DAY DESIGN STORM 3 - STORM DATA FILE SPECIFY STORM OPTION: S.C.S. TYPE-lA RAINFALL DISTRIBUTION ENTER: FREQ(YEAR), DURATION(HOUR), PRECIPCINCHES) ---------------------------------------------------------------------- S.C.S. TYPE-lA DISTRIBUTION 2-YEAR 24-HOUR STORM **** 1.50" TOTAL PRECIP. ---------------------------------------------------------------------- ENTER: A(PERV), CN(PERV), A(IMPERV), CN(IMPERV), TC FOR BASIN NO. 1 DATA PRINT-OUT: AREA(ACRES) PERVIOUS IMPERVIOUS TC(MINUTES) A CN A CN 1.0 .946 85.0 .064 98.0 24.0 PEAK-Q(.CFS) T-PEAK(HRS) VOL(CU-FT) 7.83 1842 ENTER [d:][path]filename[.ext] FOR STORAGE OF COMPUTED HYDROGRAPH: FILE ALREADY EXIST; OVERWRITE (Y or N) ? SPECIFY: C - CONTINUE, N - NEWSTORM, P - PRINT, S - STOP STORM OPTIONS: Page 1 Nortonreport.txt 1 - S.C.S. TYPE-lA 2 - 7-DAY DESIGN STORM 3 - STORM DATA FILE SPECIFY STORM OPTION: S.C.S. TYPE-lA RAINFALL DISTRIBUTION ENTER: FREQ(YEAR), DURATION(HOUR), PRECIP(INCHES) ---------------------------------------------------------------------- S.C.S. TYPE-lA DISTRIBUTION 10-YEAR 24-HOUR STORM **** 2.00" TOTAL PRECIP. ---------------------------------------------------------------------- ENTER: A(PERV), CN(PERV), A(IMPERV), CN(IMPERV), TC FOR BASIN NO. 1 DATA PRINT-OUT: AREA(ACRES) PERVIOUS IMPERVIOUS TC(MINUTES) A CN A CN 1.0 .946 85.0 .064 98.0 24.0 PEAK-Q,�G_FS) T-PEAK(HRS) VOL(CU-FT) 7.83 3127 ENTER [d:][path]filename[.ext] FOR STORAGE OF COMPUTED HYDROGRAPH: FILE ALREADY EXIST; OVERWRITE (Y or N) ? SPECIFY: C - CONTINUE, N - NEWSTORM, P - PRINT, S - STOP STORM OPTIONS: 1 - S.C.S. TYPE-lA 2 - 7-DAY DESIGN STORM 3 - STORM DATA FILE SPECIFY STORM OPTION: S.C.S. TYPE-lA RAINFALL DISTRIBUTION ENTER: FREQ(YEAR), DURATION(HOUR), PRECIP(INCHES) ---------------------------------------------------------------------- S.C.S. TYPE-lA DISTRIBUTION 100-YEAR 24-HOUR STORM **** 3.00" TOTAL PRECIP. ---------------------------------------------------------------------- ENTER: A(PERV), CN(PERV), A(IMPERV), CN(IMPERV), TC FOR BASIN NO. 1 DATA PRINT-OUT: AREACACRES) PERVIOUS IMPERVIOUS TC(MINUTES) A CN A CN 1.0 .946 85.0 .064 98.0 24.0 PEAK-qf,CFS) T-PEAK(HRS) VOL(CU-FT) (3�) 7.83 6071 ENTER [d:][path]filename[.ext] FOR STORAGE OF COMPUTED HYDROGRAPH: FILE ALREADY EXIST; OVERWRITE (Y or N) ? SPECIFY: C - CONTINUE, N - NEWSTORM, P - PRINT, S - STOP STORM OPTIONS: 1 - S.C.S. TYPE-lA Page 2 Nortonreport.txt 2 - 7-DAY DESIGN STORM 3 - STORM DATA FILE SPECIFY STORM OPTION: S.C.S. TYPEAA RAINFALL DISTRIBUTION ENTER: FREQ(YEAR), DURATION(HOUR), PRECIP(INCHES) ---------------------------------------------------------------------- S.C.S. TYPEAA DISTRIBUTION 2-YEAR 24-HOUR STORM **** 1.50- TOTAL PRECIP. ---------------------------------------------------------------------- ENTER: A(PERV), CN(PERV), A(IMPERV), CN(IMPERV), TC FOR BASIN NO. 1 DATA PRINT-OUT: AREA(ACRES) PERVIOUS IMPERVIOUS TC(MINUTES) A CN A CN 1.0 .862 86.0 .148 98.0 10.0 PEAK-OCCFS) T-PEAK(HRS) VOL(CU-FT) 7.83 2226 ENTER [d:][path]filename[.eXt] FOR ST004GE OF COMPUTED HYDROGRAPH: FILE ALREADY EXIST; OVERWRITE (Y or N) ? SPECIFY: C - CONTINUE, N - NEWSTORM, P - PRINT, S - STOP STORM OPTIONS: 1 - S.C.S. TYPEAA 2 - 7-DAY DESIGN STORM 3 - STORM DATA FILE SPECIFY STORM OPTION: S.C.S. TYPEAA RAINFALL DISTRIBUTION ENTER: FREQ(YEAR), DURATION(HOUR), PRECIP(INCHES) ---------------------------------------------------------------------- S.C.S. TYPEAA DISTRIBUTION 10-YEAR 24-HOUR STORM **** 2.00- TOTAL PRECIP. ---------------------------------------------------------------------- ENTER: A(PERV), CN(PERV), A(IMPERV), CN(IMPERV), TC FOR BASIN NO. 1 DATA PRINT-OUT: AREA(ACRES) PERVIOUS IMPERVIOUS TC(MINUTES) A CN A CN 1.0 .862 86.0 .148 98.0 10.0 PEAK-QCFS) T-PEAK(HRS) VOL(CU-FT) (21) 7.83 3607 ENTER [d:][path]filename[.ext] FOR STORAGE OF COMPUTED HYDROGRAPH: FILE ALREADY EXIST; OVERWRITE (Y or N) ? SPECIFY: C - CONTINUE, N - NEWSTORM, P - PRINT, S - STOP STORM OPTIONS: 1 - S.C.S. TYPEAA 2 - 7-DAY DESIGN STORM Page 3 Nortonreport.txt 3 - STORM DATA FILE SPECIFY STORM OPTION: S.C.S. TYPE-lA RAINFALL DISTRIBUTION ENTER: FREQ(YEAR), DURATION(HOUR), PRECIP(INCHES) ---------------------------------------------------------------------- S.C.S. TYPE-lA DISTRIBUTION 100-YEAR 24-HOUR STORM **** 3.00" TOTAL PRECIP. ---------------------------------------------------------------------- ENTER: A(PERV), CN(PERV), A(IMPERV), CN(IMPERV), TC FOR BASIN NO. 1 DATA PRINT-OUT: AREA(ACRES) PERVIOUS IMPERVIOUS TC(MINUTES) A CN A CN 1.0 .862 86.0 .148 98.0 10.0 PEAK-Q FS) T-PEAK(HRS) VOL(CU-FT) & 7.83 6684 ENTER [d:][path]filename[.eXt] FOR STORAGE OF COMPUTED HYDROGRAPH: FILE ALREADY EXIST; OVERWRITE CY or N) ? SPECIFY: C - CONTINUE, N - NEWSTORM, P - PRINT, S - STOP ---------------------------------------------------------------------- KING COUNTY DEPARTMENT OF PUBLIC WORKS surface water management DiVision HYDROGRAPH PROGRAMS Version 4.21B 1 - INFO ON THIS PROGRAM 2 - SBUHYD 3 - MODIFIED SBUHYD 4 - ROUTE 5 - ROUTE2 6 - ADDHYD 7 - BASEFLOW 8 - PLOTHYD 9 - DATA 10 - RDFAC 11 - RETURN TO DOS ENTER OPTION: R/D FACILITY DESIGN ROUTINE SPECIFY TYPE OF R/D FACILITY: 1 - POND 4 - INFILTRATION POND 2 - TANK 5 - INFILTRATION TANK 3 - VAULT 6 - GRAVEL TRENCH/BED Page 4 Nortonreport.txt ENTER: TANK DIAMETER (ft), EFFECTIVE STORAGE DEPTH (ft) ENTER [d:][path]filename[.ext] OF PRIMARY DESIGN INFLOW HYDROGRAPH: PRIMARY DESIGN INFLOW PEAK = .45 CFS ENTER PRIMARY DESIGN RELEASE RATE(CfS): ENTER NUMBER OF INFLOW HYDROGRAPHS TO BE TESTED FOR PERFORMANCE (5 MAXIMUM): ENTER [d:][path]filename[.ext] OF HYDROGRAPH 1: ENTER TARGET RELEASE RATECCfS): ENTER [d:][path]filename[.ext] OF HYDROGRAPH 2: ENTER TARGET RELEASE RATE(CfS): ENTER [d:][path]filename[.ext] OF HYDROGRAPH 3: ENTER TARGET RELEASE RATE(CfS): ENTER: NUMBER OF ORIFICES, RISER-HEAD(ft), RISER-DIAMETER(in) RISER OVERFLOW DEPTH FOR PRIMARY PEAK INFLOW .13 F-r SPECIFY ITERATION DISPLAY: Y - YES, N - NO SPECIFY: R - REVIEW/REVISE INPUT, C - CONTINUE SUMMARY OF INPUT ITEMS 1) TYPE OF FACILITY: TANK 2) TANK DIAMETER(ft), STORAGE DEPTH(ft): 3) VERTICAL PERMEABILITY(min/in): .00 4) PRIMARY DESIGN HYDROGRAPH FILENAME: 5) PRIMARY RELEASE RATE(CfS): .32 6) NUMBER OF TEST HYDROGRAPHS: 3 TEST HYD 1 FILENAME: N2.d TEST HYD 2 FILENAME: Nl0.d TEST HYD 3 FILENAME: N10O.d 4.00, 4.00 N100. d TARGET RELEASE(CfS): .04 TARGET RELEASE(CfS): .14 TARGET RELEASE(CfS): .32 7) NUMBER -OF -ORIFICES, RISER-HEAD(ft), RISER-DIAM(in): 2, 4.00, 12 8) ITERATION DISPLAY: NO SUMMARY OF INPUT ITEMS 1) TYPE OF FACILITY: TANK 2) TANK DIAMETER(ft), STORAGE DEPTH(ft): 4.00, 4.00 3) VERTICAL PERMEABILITY(min/in): .00 4) PRIMARY DESIGN HYDROGRAPH FILENAME: N10O.d 5) PRIMARY RELEASE RATE(CfS): .32 Page 5 6) NUMBER OF TEST HYDROGRAPHS: 3 TEST HYD 1 FILENAME: N2.d TEST HYD 2 FILENAME: N10.d TEST HYD 3 FILENAME: N10O.d Nortonreport.txt TARGET RELEASE(CfS): .04 TARGET RELEASE(CfS): .14 TARGET RELEASE(CfS): .32 7) NUMBER -OF -ORIFICES, RISER-HEAD(ft), RISER-DIAM(in): 2, 4.00, 12 8) ITERATION DISPLAY: NO ENTER ITEM NUMBER TO BE REVISED (ENTER ZERO IF NO REVISIONS ARE REQUIRED): ENTER: NUMBER OF ORIFICES, RISER-HEAD(ft), RISER-DIAMETER(in) RISER OVERFLOW DEPTH FOR PRIMARY PEAK INFLOW .13 FT SPECIFY: R - REVIEW/REVISE INPUT, C - CONTINUE INITIAL STORAGE VALUE FOR ITERATION PURPOSES: 1689 CU-FT BOTTOM ORIFICE: ENTER Q-MAX(CfS) DIA.= .80 INCHES TOP ORIFICE: ENTER HEIGHT(ft) DIA.= 2.76 INCHES PERFORMANCE: INFLOW TARGET -OUTFLOW ACTUAL -OUTFLOW PK-STAGE STORAGE DESIGN HYD: .45 .32 .32 3.99 749 TEST HYD 1: .13 .04 .04 2.14 400 TEST HYD 2: .23 .14 .15 2.45 480 TEST HYD 3: .45 .32 .32 3.99 740 SPECIFY: D - DOCUMENT, R - REVISE, A ADJUST ORIF, E - ENLARGE, S - STOP PERFORMANCE: INFLOW TARGET -OUTFLOW ACTUAL -OUTFLOW PK-STAGE STORAGE DESIGN HYD: .45 .32 .32 3.99 749 TEST HYD 1: .13 .04 .04 2.14 400 TEST HYD 2: .23 .14 .15 2.45 480 TEST HYD 3: .45 .32 .32 3.99 740 STRUCTURE DATA: R/D TANK (FLAT GRADE) RISER -HEAD TANK-DIAM STOR-DEPTH TANK -LE 4.00 Fr U�ffj 4. 00 FT- 7 FT DOUBLE ORIFICE RESTRICTOR: DIA(INCHES) HT(FEET) BOTTOM ORIFICE: .00 TOP ORIFICE: L2.76-i 2.10 ROUTING DATA: STAGE(FT) .00 .40 .80 1.20 1.60 2.00 2.10 2.40 2.80 3.20 3.60 DISCHARGE(CFS) .00 .01 .02 .02 .02 .02 .03 .14 .20 .25 .29 STORAGE(CU-Fr) .0 39.0 106.8 189.3 280.2 375.0 398.9 469.9 560.8 643.3 Page 6 STORAGE -VOLUME 749 cu-Fr Q-MAX(CFS) .035 .285 PERM-AREA(SQ-FF) .0 .0 .0 .0 .0 .0 .0 .0 .0 .0 . - �14 APPENDIX C