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HomeMy WebLinkAboutSW3170305_Calculations_20230517Project Report for Larkin Multi -Family Development Iredell County, North Carolina Date: May 5, 2017 Client: True Homes 2649 Brekonridge Centre Drive, Suite 104 Monroe, North Carolina 28110 Engineer: 41 it R. JOE fURRIS R ASSOCIATES, INC. Engineering . Surveying . Planning . Management 127 Ben Casey Drive, Suite 101 Fort'VIill, SC 29708 P:(803) 802-1799 mvivajoeharris.com %%% CARp % .```'�N CARO N, �,��`o� • .fix , 2.•Q�EE55/pys�y,''�: SEAL e = :W SEAL ?; C -4168:x' 2 s 036836 t '� : �p • Qom. "ntntntua+` s/r'j'��enutttta"• Report - 2nd Submittal to NCDEQ Larkin MF Development Project Report Section 2: Project Information Overall Project Information Larkin Multi -Family Development Project Report A. PROJECT DESCRIPTION Summary The Larkin Multi -Family Development is a Planned Development located west of Interstate 77, at the intersection of Fox Den Cir and 10th Green Ct, north of Amity Hill Rd in Iredell County, North Carolina. This development consists of approximately 4.79 acres consisting of 29 townhome units. This property has a Tax Parcel Number of 80031471, Deed Book number of 2390 and Deed Book Page Number of 3. The site is currently cleared with the exception of a couple existing buildings and trees that will be removed. The site is also moderately sloped. The predominant soil types within the proposed limits of construction are Cecil sandy loam, and Cecil - Urban land complex; all of which belong to the Soil Hydraulic Group B (as taken from the Web Soil Survey 2.1— National Cooperative Soil Survey by NRCS). The disturbance for the site will encompass roughly 4.00 acres. The site will encounter two phases of erosion and sediment control management, beginning with an initial phase. Initial clearing, grading and infrastructure placement will occur during this phase. The last phase (stabilization or final phase) will include paving and stabilization of the site. Given the amount of grading work that will take place, the majority of the erosion control is best managed through the use of sediment basins with temporary diversion ditches to help channel flow to the aforementioned basins. Accessory features such as inlet protection, silt fence, and concentration outlets will also be used to assist with bypass areas and smaller areas of concentrated flow. Three sediment basins have been specified for the initial phase erosion control. The three basins will remain active during the final phase of erosion control and sediment management. The storm drainage installation will either be staged (stub pipes) or include temporary pipes to effectively discharge the storm water into the basins until all work has been completed. At this point, the sediment basins will be converted into permanent BMP ponds and the temporary pipes will be discarded and permanent pipes installed in order for the storm systems to effectively discharge into the permanent BMP ponds. B. STORMWATER MANAGEMENT Pre and Post development flows were analyzed at two different locations on the Larkin MF Development site due to a high point on the site during the pre -development stage and the storm system during the post development stage. The first point of analysis is an existing catch basin located in the North West corner of the site on 101h Green Ct. The second point of analysis is located at an existing ditch in the South West corner of the site were the ditch discharges water off the site. For the purposes of this analysis the pre -development conditions account for potential proposed impervious area as a result of previous designed residential development for this site. With the installation of the proposed BMP Wet pond and BMP Detention Ponds with Sand Filters on this site, it was observed that the post development condition improved on that of the pre -development conditions Pre and Post Development runoff summaries can be found in Section III of this project report and in summary for the 2 -Year and 10 -Year Storm Events. Larkin Multi -Family Development Project Report Pre -Development Runoff (North West) Pre Area #1 Post Development Runoff (North West) Post Area #2 Post Area #3 Bypass Area #4 Bypass Area #5 Combined Pre -Development Runoff (South West) Pre -Area #2 Post Development Runoff (South West) Post Area #1 C. WATER QUALITY Project Summary Area (Ac.) 2 Yr (cfs) 10 Yr (cfs) 3.86 9.21 17.55 1.05 0.54 4.80 0.77 0.09 2.54 1.08 1.72 3.82 0.66 1.60 3.06 3.56 3.40 13.34 1.20 2.23 4.87 1.15 0.06 0.59 There are 5 main drainage areas that make up the two points of discharge locations. Four of the five areas are collectively discharged into an existing storm system by means of an existing storm structure located in the North West corner of the site. The remaining area discharges into an existing ditch which discharges water of the site in the South West corner. There are no proposed impacts to jurisdictional Waters of the State (WoS). In order to achieve the intended water quality the storm outfalls for this site have been routed into the permanent BMP ponds where the water is to be detained for a period of time between 48 and 96 hours before being released into the into the designated discharge locations. BMP Detention Pond with Sand Filter #200 and BMP Detention Pond with Sand Filter #300 will discharge into the existing storm structure in the North West corner of the site, while BMP Wet Pond #100 will discharge into the existing ditch in the South West corner of the site. The BMP Detention ponds were designed to collect the 100 -year flow from the site and allow it to collect in the wet pond to an elevation of that not exceeding that of the emergency spillway in each pond, or 1ft of freeboard between the water elevation and the top of the berm of each wet pond. D. STORM DRAINAGE SYSTEM An analysis of all receiving storm drainage systems within the Larkin Multi -Family Development was conducted to verify that the drainage systems would not surcharge or be beyond capacity due to the drainage areas and the storm water runoff from the site for the 10 -year, 24-hour rainfall intensity. All of the street catch basins have been evaluated for inlet spread using the 1 -year, 24-hour rainfall intensity, and all yard inlets have been evaluated for sump capacity using the 10 -year, 24-hour rainfall intensity. For the analysis of the infrastructure, R1H utilized a combination of field -run topography for the area and proposed lot/road grading to evaluate each of the storm drain systems. All storm systems are new systems designed from drainage within the limits of the Marthas Ridge Subdivision and also from off-site drainage. All storm systems function within the design parameters set forth by the Town of Statesville, Iredell County and NCDOTfor both pipe design and inlet spread capacity. Larkin Multi -Family Development Project Report Project Summary All systems have been fitted with a properly sized riprap apron at the outflow for energy dissipation. All proposed storm drain profiles have been designed to limit the hydraulic gradient line (HGQ to no closer than 0.5' below the weir/rim elevation. End Report Larkin MF Development Project Report Section 6: Water Quality Calculations Permanent Wet Pond 100 Bottom B. Shelf Pool T. Shelf T. Berm PROJECT NAME: PROJECT #: DESCRIPTION: Larkin MF Development DATE: 9 -Nov -16 2382 DESIGNER: A. Bowersox Pond #100 -Permanent Pond Volume ENGINEER: A. Bowersox PERMANENT POOL STORAGE VOLUME: ELEV. (FT.) CONTOUR AREA (S.F.) ELEVATION DIFFERENTIAL (FT.) INCREMENTAL VOLUME (C.F.) ACCUM. VOLUME (C.F.) 862.50 390 0.0 0 0.00 863.00 757 0.5 282 282 864.00 1,597 1.5 1,151 1,433 865.00 2,586 2.5 2,072 3,505 865.50 3,170 3.0 1,437 4,941 866.00 4,093 3.5 1,811 6,752 866.50 1 1 5,005 4.0 2,271 9,023 867.00 5,575 4.5 2,644 11,666 868.00 6,767 5.5 6,161 17,828 869.00 8,025 6.5 7,387 25,215 870.00 9,367 7.5 8,687 33,902 871.00 10,026 8.5 9,695 43,597 Bottom Top PROJECT NAME: Larkin MF Development PROJECT #: 2382 DESCRIPTION: Pond #100 - Forebay PERMANENT POOL STORAGE VOLUME: DATE: 9 -Nov -16 DESIGNER: A. Bowersox ENGINEER: A. Bowersox ELEV. AREA DIFFERENTIALCONTOUR ELEVATION INCREMENTAL ACCUM. Larkin MF Development Statesville, North Carolina Project Number: 2382 November 9, 2016 COMPOSITE SCS RUNOFF CURVE NUMBERS 24 Hour Storm Event BMP Wetpond #100 Soil Type: Cecil sandy clay loam, Cecil -Urban Land Complex - HSG "B" Total Drainage Area = 1.18 ac. Paved Roads/Sidewalk/Structures 0.55 ac. CN = 98 Wooded Area CN = 60 0.00 ac. Good Grass (>75% of area) 0.63 ac. CN = 61 Newly Graded CN = 86 Composite CN 78.25 0.00 ac. W a CL w W O U N�N 1.1. O LL N W F - Z W m W J a a_^ V/ �l T ` i ,moi @ Zsr ,gib•.• �•Q.C,. ,,,III/IIIIIIIII���a O N 3 m D `o C C O O � U T � @ N @ @ N O C C O o a D c U J '- o U a � c @ s � � L O � T O O O N C m w _T C � N J Q @ U 0 � m m E w m c@ > O O>@ fn EL a o� a= c a a C 6] J � �l ,��'t.�®salllagllll�Io • •..... Y sad%- ` i ,moi S'ty fA Zsr ,gib•.• �•Q.C,. ,,,III/IIIIIIIII���a C N E _O (D 0 LL c_ m J 0 Z `a r LU �E ! i o O U a� i E ag �m o� E o I ❑ n NI m.� N 0 � Q W _ L O N ❑ m �❑ T m '. a ° c a U U° . o. a C m lA N_ O W 0 ; 5 m$ N? 0 m) z yx a m `o 3 _ O. O U m o rm al, ml E z. a m N ?L c a m a 0 o _= m d N K K O n rn E: w O ❑ W w N 0❑❑❑ 4 r- Q m❑ 0 2 m 0 I m Z Z 4 z m• i m w a > ri Z m m> �2> m `m i 'm m s g I of t e c O vl U o m 0 u ITlq` $' o 16 J uni ry$ a N O a c O j 0 y m E-2 E � in I�Um c o$ m E$mq-a-tc m E S 5 c a T am. t m E� E ° z `o O E n i o 16 `o 16 `p y m 2 m m o FF a$$ m m g' d, V E o m m m° o o z° $ xy c m. m Z y 0 0 o L 2 °W c n 2 $ m O O Z L alm J ¢ V_ i m y m O $ m .P m m^ c c 3 p . 0 T N V 7 N y umii'c63 o N W�.� G N N $mSL60C O>mmm Nmmm�Smm � m-fN W C Vp Vp � ¢ ($ f E 2-' m 3 ❑ ¢ '-' 3 W � rq > ¢ 3 w w w ❑ � ❑ E > '_^ ❑ ❑ U >i G m Larkin MF Development Wet Detention Pond #100 September 23, 2016 Drainage Area: 1.18 Acres % Impervious: 46.31 Percent Pond Depth: 3.5 Feet SA/DA: 1.8 Required Surface Area = (1.8/100) X 1.18Acres X 43,560 S.F./Ac. = 925 Sq.Ft. (OK - See Surface Area of Permanent Pool = 4,093 sq.ft.) Runoff Coefficient = 0.05 +.009 (% Impervious) = 0.467 in./in. Volume (To Be Controlled) = Design Rainfall X Runoff Volume X Drainage Area _ (lin. Rainfall) X (0.4671n./in.) X (1/12 feet/in.) X (1.18acres) X (43,560 sq.ft/acre) = 1,999 cu.ft. (OK -2,005 cu.ft. @ 866.28' MSG when there is no release) Release Rate = (1999 cu.ft.)/((2 days) X (86,400 sec./day)) = 0.012 cu.ft./sec. From Hydrograph Model (3 -yr Storm Event) Peak Discharge Rate = 0.019 cu.ft./sec. (@ 866.27 MSG) Average Discharge Rate = [ (0.000+0.019) /2 ] = 0.010 cu.ft./sec. Time to Drain 1" Rainfall = Volume/Avg Discharge _ (1999 CF)/(0.01 CFS) = 210,468 sec. = 58.463 hours = 2.44 days Water Quality Volume = 6,752 cu.ft. See Attached Permanent Pool Chart Required Forebay Volume = (20%) X (Water Quality Pool Volume) ' At permanent pool level = 1,350 cu.ft. Forebay Volume Provided = See Attached Forebay Volume Chart = 1,814 cuff. = 26.87% (OK - Forebay volume should be minimum 20% of permanent pool volume) Culvert Report Hydraflow Express Extension for Autodesk® AutoCAD® Civil 3D® by Autodesk, Inc. Friday, May 5 2017 Basin #100 Final Invert Elev Dn (ft) = 865.00 Calculations Pipe Length (ft) = 63.00 Qmin (cfs) = 4.81 Slope (%) = 1.59 Qmax (cfs) = 4.81 Invert Elev Up (ft) = 866.00 Tailwater Elev (ft) = (dc+D)/2 Rise (in) = 15.0 Shape = Circular Highlighted Span (in) = 15.0 Qtotal (cfs) = 4.81 No. Barrels = 1 Qpipe (cfs) = 4.81 n -Value = 0.012 Qovertop (cfs) = 0.00 Culvert Type = Circular Concrete Veloc Dn (ft/s) = 4.30 Culvert Entrance = Square edge w/headwall (C) Veloc Up (ft/s) = 5.16 Coeff. K,M,c,Y,k = 0.0098, 2, 0.0398, 0.67, 0.5 HGL Dn (ft) = 866.07 HGL Up (ft) = 866.89 Embankment Hw Elev (ft) = 867.44 Top Elevation (ft) = 871.00 Hw/D (ft) = 1.15 Top Width (ft) = 20.00 Flow Regime = Inlet Control Crest Width (ft) = 159.00 Basin 91N Final Hw[KP6+lfl1 600 6.. 4. 3.00 IN . 0. -1. S. R.&tm WM CfraYVGYVM HGL E..k Hydrograph Summary Re P% aflow Hydrographs Extension for AutoCAD® Civil 3D@2016 by Autodesk, Inc. v10.5 Hyd. No. Hydrograph type (origin) Peak flow (cfs) Time interval (min) Time to Peak (min) Hyd. volume (cuft) Inflow hyd(s) Maximum elevation (ft) Total strge used (cuft) Hydrograph Description I SCS Runoff 0.949 1 718 2,005 --- ------ ------ Wet Pond #100 2 Reservoir 0.019 1 1146 1,746 1 866.28 1,264 Wet Pond Wet Pond #100.gpw Return Period: 3 Year Friday, 05 / 5 / 2017 2 Hydrograph Report Hydraflow Hydrographs Extension for AutoCAD® Civil 3D® 2016 by Autodesk, Inc. v10.5 Friday, 05 / 5 / 2017 Hyd. No. 1 Wet Pond #100 Hydrograph type = SCS Runoff Peak discharge = 0.949 cfs Storm frequency = 3 yrs Time to peak = 718 min Time interval = 1 min Hyd. volume = 2,005 cuft Drainage area = 1.150 ac Curve number = 78.1 Basin Slope = 0.0% Hydraulic length = 0 ft Tc method = User Time of conc. (Tc) = 5.00 min Total precip. = 1.96 in Distribution = Type II Storm duration = 24 hrs Shape factor = 484 Wet Pond #100 Q (cfs) Hyd. No. 1 -- 3 Year Q (cfs) 1.00 0.90 0.80 0.70 0.60 0.50 0.40 0.30 0.20 0.10 000 1.00 0.90 0.80 0.70 0.60 0.50 0.40 0.30 0.20 0.10 000 0 120 240 360 480 600 720 840 960 1080 1200 1320 1440 1560 Hyd No. 1 Time (min) 3 Hydrograph Report Hydraflow Hydrographs Extension for AutoCAD® Civil 3D@ 2016 by Autodesk, Inc. v10.5 Friday, 05 / 5 / 2017 Hyd. No. 2 3000 Wet Pond (min) — Hyd No. 2Time — Hyd No. 1 Hydrograph type = Reservoir Peak discharge = 0.019 cfs Storm frequency = 3 yrs Time to peak = 1146 min Time interval = 1 min Hyd. volume = 1,746 cuft Inflow hyd. No. = 1 -Wet Pond #100 Max. Elevation = 866.28 ft Reservoir name = Wet Pond #100 Max. Storage = 1,264 cuft Storage Indication method used. Wet Pond Q (cfs) Hyd. No. 2 -- 3 Year Q (cfs) 1.00 0.90 0.80 0.70 0.60 0.50 0.40 0.30 0.20 0.10 000 1.00 0.90 0.80 0.70 0.60 0.50 0.40 0.30 0.20 0.10 000 0 300 600 900 1200 1500 1800 2100 2400 2700 3000 (min) — Hyd No. 2Time — Hyd No. 1 ®Total storage used = 1,264 cult Pond Report Hydraflow Hydrographs Extension for AutoCAD® Civil 3D@2016 by Autodesk, Inc. 00.5 Pond No. 7 - Wet Pond #100 Pond Data Contours -User-defined contour areas. Conic method used for volume calculation. Begining Elevation = 866.00 ft Stage / Storage Table Stage (ft) Elevation (ft) Contour area (sgft) Incr. Storage (cuft) Total storage (cuft) 0.00 866.00 4,093 0 0 0.50 866.50 5,005 2,270 2,270 1.00 867.00 5,575 2,643 4,914 2.00 868.00 6,767 6,161 11,075 3.00 869.00 8,025 7,386 18,461 4.00 870.00 9,367 8,686 27,148 5.00 871.00 10,026 9,694 36,841 El Friday, 05 / 5 / 2017 Culvert / Orifice Structures Note: CulverVOrifice outflows are analyzed under inlet(ic) and outlet (cc) control. Weir risers checked for orifice conditions(ic) and submergence (a), Weir Structures Storage / Discharge Table [A] [B] [C] [PrtRsr] Stage [A] [B] [C] [D] Rise (in) = 15.00 1,25 6.00 0.00 Crest Len (ft) = 8.00 173.00 0.00 0.00 Span (in) = 15.00 1.25 12.00 0.00 Crest EI. (ft) = 869.00 870.00 0.00 0.00 No. Barrels = 1 1 1 0 Weir Coeff. = 3.33 3.33 3.33 3.33 Invert EI. (ft) = 866.00 866.00 867.00 0.00 Weir Type = 1 Ciplti --- --- Length(ft) = 63.00 0.00 0.00 0.00 Multi -Stage = Yes No No No Slope (%) = 1.59 0.00 0.00 n/a --- 0.00 0.00 --- --- --- --- 3.244 4.00 27,148 N -Value = .013 .013 .013 n/a 0.00 --- --- --- --- 10.76 5.00 36,841 871.00 Orifice Coeff. = 0.60 0.60 0.60 0.60 Exfil.(in/hr) = 0.000 (by Contour) Multi -Stage = n/a Yes Yes No TW Elev. (ft) = 0.00 Note: CulverVOrifice outflows are analyzed under inlet(ic) and outlet (cc) control. Weir risers checked for orifice conditions(ic) and submergence (a), Stage / Storage / Discharge Table Stage Storage Elevation Clv A Clv B CIV C PrtRsr Wr A Wr B Wr C Wr D Exfil User Total ft cuft ft cfs cfs cfs cfs cfs cfs cfs cfs cfs cfs cfs 0.00 0 866.00 0.00 0.00 0.00 --- 0.00 0.00 --- -- --- --- 0.000 0.50 2,270 866.50 0.03 is 0.03 is 0.00 -- 0.00 0.00 --- --- --- --- 0.027 1.00 4,914 867.00 0.04 is 0.04 is 0.00 --- 0.00 0.00 --- --- --- --- 0.039 2.00 11,075 868.00 2.16 is 0.05 is 2.08 is --- 0.00 0.00 --- --- --- --- 2.131 3.00 18,461 869.00 3.27 is 0.06 is 3.18 is --- 0.00 0.00 --- --- --- --- 3.244 4.00 27,148 870.00 10.76 is 0.01 is 0.57 is --- 10.18s 0.00 --- --- --- --- 10.76 5.00 36,841 871.00 12.34 is 0.00 is 0.26 is -- 12.05s 576.09 --- --- -- --- 588.40 Larkin MF Development Project Report Section 6: Water Quality Calculations Permanent Detention Pond with Sand Filter 200 Larkin MF Development Statesville, North Carolina Project Number: 2382 November 9, 2016 COMPOSITE SCS RUNOFF CURVE NUMBERS 24 Hour Storm Event BMP Detention Pond with Sand Filter #200 Soil Type: Cecil sandy clay loam, Cecil -Urban Land Complex - HSG "B" Total Drainage Area = 1.05 ac. Paved Road s/Sidewalk/Structu res 0.51 ac. CN = 98 Wooded Area CN = 60 0.00 ac. Good Grass (>75% of area) 0.54 ac. CN = 61 Newly Graded CN = 86 Composite CN 79.0 0.00 ac. SAND FILTER Larkin MF Development THE DRAINAGEAREA f Oner"e_rea number To. cosml andiandsa,.a amft) 2 IBm.k down of Bull In the tlralnayearea,(bolh naw and a.iali.,L______ - Parking f mines, pach th _ tdBO sf Trial sume- walerarea(�fl) _ _ Tell l dral may(sgft) 45707 ef mi0 -Sldawe_khm X) -Roof R, ft) 151]BC BOA associated wtlh mating detalo nt(WR 3amoof -Roadway(s4tt .504 Posed new BOA me, it)22J1]3 31i488of _Other. pleaUspecilyintheocm nt lbxlmilar � ( lNel Percent BOA of amemage area 40% Tohilaid (cgfl) 223Pd COMPL AhICE WITH THE APPLICABLE STORMWATER PROGRAM 152.d I- Olney idiaar specify in tea comment ria. below I, th - ebrmw_p �sl lmapply(pleamspecify) Design rainfall depth (in) 1Sin COMPLIANCE MI THE APPLICABLE STCIFMWATER PROGRAM Mnim in wlume.,.,atlft ]146d _�_� Oetig-lame of SCM (cu lq 2P50 or GENERAL MDC FROM O2H .1050 in #11s the SCM sized to Uat the SW from 011 uRaces al6Wldaul? #2 is the SCM hermit in wnprearMed sores? Yea No #T if applicable. with the SCM be cleaned ow after cun_stmction? #B Poem the me co _h General M00 (0)? aasemenl Ym Yes L3 What are the side slopes of SCM (HN)? 3:1 #9 des tM1e dmtnam_a comp[ wN_ GenemIMOC (9)? 9 e _Y_ Yes 93 Coas the SCM haus retainin IIs bion -alb orolneren immmasdeelo tea ga- _g_ yes?.__._ #4Arelheinlels,outlets, and race Nng stream protedea fmmeroeian(t0-yearslortn)? No I Yes Y101INe 5LM lso_ingle Tamil ICT, tloes tM1a pl lcom wlN GeneralMDL 10)? v Genera #111s IM1ere an O9M�r_memlhetw�ll_wlPaGeneral MDC (tt)? Vex Yec AS is them a abypmas Irflows of has ian(Ray #fi What -is the method for cancer, the SCM for mentenance? Yes Pm, Proarr #121 them -08M P1 ht -mi wtlM1G ral MDC (12]=I_arm ,yt3 Was the SCM tle i netl by an NC Iranian professorial? Yee SAND FILTER MDC FROM 02H.1056 Ye¢ #90aeslhe SCM havereminingwaib ebion walls or other an neeral ever, hill No #t SHNRelevm.-Ifmsp #1 face .1 -no Not, (open dialect _ #1 if cloud, dUcnbe if the f0er will l»premsl or pour -in-place: N/A Open #3 Volume of stormaymer from drainage area during design stone (cubic feep #3 Total walums,lhal can W athad — the sediment and sand Chambers (cubcfeet) 1p is this Untl filler designed to attenuate peak [laws? #3 Elavallan_f the bypass devlce(fmsp 952a 7376 of Yee 084ft #t l fctoxd lopo[gretearowdon(fmsl) yes _ !13 Bexabe the bypass deNca: YU #2 Volume t_bal can be seemed in the swiimant chamber (cubic feeq #2_ Will there be a permanent pool in the sediment cha_mbe(t 602 of NO 10 foot wide amerganry spillway Pump(praferredl 142 Bothar.flhe Udncialchambarprop fart it #6 Pending depth from the top of the send to the bypass dawre ((t) 3fl #2 Ant ancient feet) ' 419d p50exnbe the mechan m6rtllsNbulin lbw owrtM1e santl sudece: WA _chamber _(secure #2 Picracel depth of l_he sediment charmer,onches) 301n R.,Ra, apron Open _ _ #2 Ponding depth in the sediment chamber, above any permanent pool (inches) Win#e Seta spaciGcslion for card chamber 1 #2 Elevalien of to of weir belwe_ham0ars (lmsl) 4_2 Volume that can be retained in the sand chamber (,,his feat) Pb2ft 2216 of ASTM33 m imps len, _ M Be. ollbeeandchamb.,RI1l) 819th #] OepP aWva undede a pipe(none&) 15 in #2 Afra. of the and chamber(eguare feat) 1309d #B Will In. media be mai mined to had. a110ast two inches per hour at the saM surface? Y. #2 Ph,cirsldepm of the sand chamber (inches) 38 in 0 yet heard one cbanoul pipe Res"redat the low point of each underdrain line? I Yea #2 Ponding tleplh in the sand chamber class, any Amman nt post(inches) 3g in 0 Will cleanout pipes be rsppad? Yea ADDITIONAL INFORMATION _ ant chamberaep— #2 Phyvrs�ae l�hof the seaimam enamner(manes) 98 in deev o -a this space to p—de an addromall enhalion.Not Nis x ad Ilim that n thinkts relevant to the reNew: any Ponding depth in be sediment chamber ebo- any permanent pool('mcnes) 1 3r, in N $e no ape pass mr seta member #2 Eewhon.f RE-dweirbetwenmambers ffmd) _. #2 Volume bet can be rete bed In the sena chamber fares leap M5R 2a80d THE DRAINAGE AREA 2 Drainage aumbe_ I3 Break down f SUA In lhadrainaga wharf olh new and a%ullwl: ___ Total coastal wetlands area (sq R) -PaMiiy / tlrireway (sq fp B30 d TotaIwemewww.ma(agft) 3amoof -Sldewalkhal Tom, normal am. had th 31i488of -Poor I, ri ( lNel BOA asxcinim with a#sting deuelopmam(ag It) -Reatl ped ll) 1 37104 cropased new BVA her ft) 152.d I- Olney idiaar specify in tea comment ria. below I, th - Porwnt Ini of choice, am. 11i811A (a, ft) 1520) d COMPLIANCE MI THE APPLICABLE STCIFMWATER PROGRAM Sommayine, aMai that apply(leaus df) Doslgn rainfall death(in)LS in Minimum wlume required Ru ft) deign -lama of SCM (cu R) 859 d 1830 of GENERAL MDC FROM 0211.1050 #1 is the SCM sizndto treat the SW from all surmser, tbodid-em? yes d] Ila II[enle, wiN lea SLM be cleanetl out after consnuction? Yee WL Is the SCM located on or nearconlaminated eoils? I Na f13 Coea lM1a meinetetmnce access cpm I wtlh Gene21MDCOP Yes M what are the.,.. ca aofthe50M(Ry) Bt A9 Coes lee tlairre�Jent mmplywlth GeneralMDL (0)? _ Ye¢ #90aeslhe SCM havereminingwaib ebion walls or other an neeral ever, hill No #t011 the SLM is one sin le (emit to does the lalwmplywlM1 GenemIMDC (t0)? I Yes its re Oa nletsouaetIn and ra Nngs4eam pcasRetl from erocion (10.yrear stormy. Yes #12 is there an OeM Agreememlast lies MDC14? 11)?_ yes iAS lelhereaa bypass lfo llowatimmess of the YU #121s them a, O&M Pbndb ram dwe. r.Gane ( (12)?_ yea armairlew't %E Wnattslhe method brtlewetering the SCM formaintenance? Pump(praferredl Cli licensed rofeca #t3 destneSCM tlesignetl by an NCllcenxa prolessi nal? - YU SAND FILTER MDC FROM 02H .1056 #t SHIT elewtmn(fmsq WA #3 Volume of contractor from cannot. ema di all cappor hi .feel) 3839 of #t Type of sane tllter(openerclosetl) Open 1q Totalwlama Thal can lie all above the sediment and send chambers (cubic (set) al of IIIfclased,descnbeinhe than will be pea—d or pour-Irvplace 1 ip is this send lithirdenignetl W attenuate peek flows? Yes #d Elavicbroflnebypayedynce(fmsl) #t lfclasaa lop of 9ateelevellDn finep ach 0—miedhomminanday.'. 142 Wilume b Un baanenea in thea wail t thannr(cubic feel) K2 them mom pool'm me meaimem cnambe(! 12CB cf No tOfwt -tle ematgenry sglMey Forell 82 In.had chambt (final) P4 PomDewebyeepth top of me lana to has bypassaaNce lXl . 3h Ancoftnhedimentochamber(quareer _ 41 Areaorihe sediment 782X 780 of hemaamme the mmeniem for anambe0n lbw overma aces eorfaca I15 Dasa _ ant chamberaep— #2 Phyvrs�ae l�hof the seaimam enamner(manes) 98 in RnP'Hav¢pron pr --- any Ponding depth in be sediment chamber ebo- any permanent pool('mcnes) 1 3r, in N $e no ape pass mr seta member #2 Eewhon.f RE-dweirbetwenmambers ffmd) _. #2 Volume bet can be rete bed In the sena chamber fares leap M5R 2a80d ASTM93.r'prai int #2 Bottom ohne pone mamber(fmap �2k tt] Depin abeue onaerarem pipe (lnanea) leve #2 Are. of the x ad chere., m9uare feet) 1185 of #3 Will the media be maintains to stain at bast moschas per hour at the santl surface? Yes i PhWlwl depth or the conachember(Incnes) ..n and is at lead one cleanotd pi we paciaea at the low point of each unaeraann line? —`I Yes lY2 an I, tleplM1 In thasantl m anue,ebo-enypnm nantpooldrerom 3g in #9 .,It cleanout pipes b. -,,a, Yes ADMCNAL INFORIAA?ION Pleex sex this space to pmviaa an etltlitionel lnformedon aboutthls xntl (amtlhat a trim, is relewnl to lbs re view: Sand Filter 1 1:31 PM 5/4/2017 Project: Larkin MF Subdivision Sand Filter #200 Engineer: R. Joe Harris & Associates, Inc. Location: Statesville, NC Date: November 9, 2016 Client: True Homes, LLC By: M. Birmingham BMP Type: Surface Sand Filter (Pond #200) 3.5 ft/dy Compute Surface Sand Filter Area and Volume to Treat Water Quality Volume (WQv) 1.0 Check Surface Sand Filter Area based on Darcy's Equation (assumed value of 1.75 in/hr for the design coefficient of permeability for the sand filter media) Af = 7�(WQ")(df)/[(k)(hf+df)(tf)] «««««« = t 19sq.ft. Surface Area Used = Sand Filter Dims @ Filter Media = 282 sq.ft. Develop Stage -Discharge for Bioretention Filter Media 10 Width (ft) 28 Length (ft) Where: WQv 2796.28 cu. ft. Depth (Incr.)(ft) Water Quality Vol. df - 2 ft 849.0 filter bed depth 0.0 (2.5' optimal, 2.0' std) k - 3.5 ft/dy Assume "0" Discharge at Top of Soil Media permeability coeff. hf- 3 ft 197 avg. height of water tf- 1.67 days 850.0 filter bed drain time Outflow computed using following equations: Af = (WQ�)(df) / [(k)(hf + df)(tf)] Q. = WQV/tf Qa = [(Af)(k)(hf+df)]/df Where: Af = surface area of filter bed (sq.ft.)(Required Surface Area) _ sf df = filter bed depth (ft) k = coefficient of permeability of filter media (ft/day) hf = avg. height of water above filter bed (ft) Elevation Contour Area (SF) Depth (Incr.)(ft) volume (cf) Incr.Ac m. Discharge (cfs) (Filter Media) This Is For Filter Media Only Comments 849.0 302 0.0 0 0 0.000 9 Assume "0" Discharge at Top of Soil Media 849.5 486 0.5 197 1 197 0.014 850.0 670 0.5 289 486 0.017 850.5 905 0.5 394 1 880 0.020 851.0 1139 0.5 511 1391 0.023 851.3 1309.5 0.3 404 1795 0.025 Max Depth of Pond (Media to First Orifice) Project: Larkin MF Subdivision Sand Filter #200 Engineer: R. Joe Harris & Associates, Inc. Location: Statesville, NC Date: November 9, 2016 Client: True Homes, LLC By: M. Birmingham BMP Type: Surface Sand Filter - Pond #200 Size Underdrains for Surface Sand Filter The calculations utilized are taken from the NC DEQ BMP Manual, Section 5.7 Underdrain Systems 1.0 Compute number of pipes needed for the underdrain system as follows: Design flow rate thourgh sand media at WQ Peak elev. 651.33 = cfs Input Data: Rougness factor, manning's n 0.011 Internal slope, s (%.) 0.5 Underdrain Design flow, Q (cfs) 0.025 Underdrain Safety Factor - SF 10 Diameter: Equation in NC DEQ Section 5.7: D = 16[(Q*SF*n)/SA0.5)]A(3/8) D 1.99 in Table 5-1: D<5.13in Number of 4" Pipes Needed: 2 Table 5-1 Number of Pines Reauired in the Underdrain If D is less than # of 4" pipes If D is less than # of 6" pipes 5.13 2 7.84 2 5.95 3 9.11 3 6.66 4 10.13 4 7.22 5 7.75 6 8.20 7 Add the following pipe and perferation specifications, from NC DEQ BMP Manual Section 5.7, to construction plan details: All piping within the underdrain system shall have a minimum slope of 0.5 percent and shall be constructed of Schedule 40 or SDR 35 smooth wall PVC pipe. The size of pipes shall be 6 -inch diameter. The spacing of collection laterals shall be no greater than 10 feet center to center, and a minimum of two pipes should be installed to allow for redundancy. A minimum of 4 rows of perforations shall be provided around the diameter of the pipe and the perforations shall be placed 6 inches on center within each row for the entire length of the drainage lateral. Perforations shall be 3/8 -inch in diameter. The underdrain pipes shall have a minimum of 3 inches of washed #57 stone above and on each side of the pipe (stone is not required below the pipe). Above the stone, either filter fabric or two inches of choking stone (#8 or #89) is required to protect the underdrain from blockage. PROJECT: Larkin PROJECT #: 2382 DESCRIPTION: Sand Filter #200 POND STORAGE VOLUME: DATE: 9 -Nov -16 DESIGNER: MWB ENGINEER: PLM llESC. ELEV. (FT.) CONTOUR AREA (S.F.) ELEVATION DIFFERENTIAL (FT.) INCREMENTAL VOLUME (C.F.) ACCUM. VOLUME (C.F.) Bottom 849.00 302 0.0 0 0 849.50 486 0.5 197 197 850.00 670 1.0 289 486 850.50 905 1.5 394 880 851.00 1,139 2.0 511 1,391 WQV 851.33 1,310 2.3 404 1,795 851.50 1,428 2.5 233 2,027 Weir 852.00 1,716 3.0 786 2,813 852.50 1,999 3.5 929 3,742 853.00 2,281 4.0 1,070 4,812 Spillway 853.50 2,559 4.5 1,210 6,022 Top 854.00 2,837 5.0 1,349 7,371 WQVEIe� 851.33 PROJECT: Larkin PROJECT #: 2382 DESCRIPTION: Final Sediment Basin #200 POND STORAGE VOLUME: DATE: 14 -Sep -16 DESIGNER: RAS ENGINEER: PLM IDESC. ELEV. I (FT.) CONTOUR AREA (S.F.) ELEVATION DIFFERENTIAL (FT.) INCREMENTAL VOLUME (C.F.) ACCUM. VOLUME (C.F.) Bottom 849.00 24 0.0 0 0 849.50 75 0.5 25 25 850.00 125 1.0 50 75 850.50 190 1.5 79 153 851.00 255 2.0 111 265 851.50 337 2.5 148 413 852.00 419 3.0 189 602 0.21 Culvert Report Hydraflow Express Extension for Autodesk® AutoCAD® Civil 3D® by Autodesk, Inc. Thursday, May 4 2017 Basin #200 Final Invert Elev Dn (ft) = 846.70 Calculations Pipe Length (ft) = 50.17 Qmin (cfs) = 4.80 Slope (%) = 0.60 Qmax (cfs) = 4.80 Invert Elev Up (ft) = 847.00 Tailwater Elev (ft) = (dc+D)/2 Rise (in) = 15.0 ______ ,--IM®® Shape = Circular Highlighted Span (in) = 15.0 Qtotal (cfs) = 4.80 No. Barrels = 1 Qpipe (cfs) = 4.80 n -Value = 0.012 Qovertop (cfs) = 0.00 Culvert Type = Circular Concrete Veloc Dn (ft/s) = 4.30 Culvert Entrance = Square edge w/headwall (C) Veloc Up (ft/s) = 5.13 Coeff. K,M,c,Y,k = 0.0098, 2, 0.0398, 0.67, 0.5 HGL Dn (ft) = 847.77 HGL Up (ft) = 847.89 Embankment Hw Elev (ft) = 848.45 Top Elevation (ft) = 854.00 Hw/D (ft) = 1.16 Top Width (ft) = 18.00 Flow Regime = Inlet Control Crest Width (ft) = 42.00 uaa (ro Basin #M Final Hr, GMN (n) BW CkWIarCWvert -HGL Em�nk ReeN la) ]DJ 600 600 4 O 3W 200 1.00 000 , a0 -2,00 -_®-_S_ S_ .. _ ®--®/ --®..q ______ ,--IM®® - �M—� I WL7 =: CkWIarCWvert -HGL Em�nk ReeN la) ]DJ 600 600 4 O 3W 200 1.00 000 , a0 -2,00 Project Name: Larkin Ballast Pad Design for Detention Pond w/ Sand Filter #200 RJ Ref #2382 854 ft. Top of Basin 0.5 ft. Spillway Height 853.5ft. Spillway Elev. Riser Size: 24 in 853ft. Riser Weir Barrel Size: 15 in za"LD.PCS Top of Basin: 854 ft. Bottom of Basin 847 ft. 6 ft. 6.5 Riser Weir: 853 ft. III II' Spillway Height from top of Basin: 0.5 ft. 847 ft. Bottom of Basin Uplift @ Peak Elevation: Peak Elevation =853 ft. - 847 ft. Peak Elevation = 6ft. Uplift Force= (62.4)(3 ft.)(2 ft.^2) Uplift Force= 748.8 lbs Volume of Concrete Required to Stabilize Riser: 1175.616 lbs X 1/150 Ibs/ft"3= 7.83744 cubic feet Ballast Pad Dimensions: Try Volume of: 4 ft. X 4 ft. X 2 ft. 32 cubic feet Ok 32 c.f. > or equal to 7.83744 c.f. True 4 f Pad 15 in. RCP 24"I.D.PCS 4 ft. Pad Ballast Pad Dimensions: 4 ft. X 4 ft. X 2 ft. Hydrograph Summary Re Kyld aflow Hydrographs Extension for AutoCAD® Civil 3D@2016 by Autodesk, Inc. v10.5 Hyd. No. Hydrograph type (origin) Peak flow (cfs) Time interval (min) Time to Peak (min) Hyd. volume (cult) Inflow hyd(s) Maximum elevation (ft) Total strge used (cult) Hydrograph Description 1 SCS Runoff 2.343 1 718 4,705 ------ ------ ------ Sand Filter#200 2 Reservoir 0.077 1 864 2,869 1 851.95 2,725 Sand Filter#200 Sand Filter #200.gpw Return Period: 1 Year Thursday, 05 / 4 / 2017 1 Hydrograph Report Hydraflow Hydrographs Extension for AutoCAD® Civil 3D@2016 by Autodesk, Inc. 00.5 Thursday, 0514 / 2017 Hyd. No. 1 Sand Filter #200 Hydrograph type = SCS Runoff Peak discharge = 2.343 cfs Storm frequency = 1 yrs Time to peak = 718 min Time interval = 1 min Hyd. volume = 4,705 cuft Drainage area = 1.050 ac Curve number = 78.9 Basin Slope = 0.0% Hydraulic length = 0 ft Tc method = User Time of conc. (Tc) = 5.00 min Total precip. = 3.02 in Distribution = Type II Storm duration = 24 hrs Shape factor = 484 Q (cfs) 3.00 2.00 1.00 Sand Filter #200 Hyd. No. 1 -- 1 Year 120 240 360 480 600 720 840 960 Hyd No. 1 Q (cfs) 3.00 2.00 1.00 0.00 1080 1200 1320 1440 1560 Time (min) Hydrograph Report Hydraflow Hydrographs Extension for AutoCAD® Civil 3D@2016 by Autodesk, Inc. v10.5 Hyd. No. 2 Sand Filter #200 Hydrograph type = Reservoir Peak discharge Storm frequency = 1 yrs Time to peak Time interval = 1 min Hyd. volume Inflow hyd. No. = 1 - Sand Filter #200 Max. Elevation Reservoir name = Sand Filter #200 Max. Storage Storage Indication method used. Q (cfs) 3.00 go 1.00 Sand Filter #200 Hyd. No. 2 -- 1 Year `- Thursday, 05 / 4 / 2017 = 0.077 cfs = 864 min = 2,869 cuft = 851.95 ft = 2,725 cuft 0.00 0 180 360 540 720 900 1080 1260 1440 1620 1800 Hyd No. 2 Hyd No. 1 ® Total storage used = 2,725 cuft Q (cfs) 3.00 2.00 1.00 1 0.00 1980 Time (min) Pond Report s Hydraflow Hydrographs Extension for AutoCAD® Civil 3D® 2016 by Autodesk, Inc. 00.5 Thursday, 05 14 12017 Pond No. 1 - Sand Filter #200 Pond Data Contours -User-defined contour areas. Conic method used for volume calculation. Begining Elevation = 849.00 ft Stage / Storage Table Stage (ft) Elevation (ft) Contour area (sqft) Incr. Storage (cuft) Total storage (cuft) 0.00 849.00 Note: CulveNOrrifice outflows are analyzed under inlet uc) and outlet (oc) control. Weir risers checked for orifice conditions(ic) and submergence (s). 302 Storage / 0 Table 0 0.50 849.50 486 195 Storage 195 CIvA CIvB 1.00 850.00 WrA 670 WrD Exfil 288 Total 483 cuft ft 1.50 850.50 cfs 905 cfs 392 cfs cfs 875 cfs 0.00 2.00 851.00 0.00 1,139 0.00 510 0.00 1,385 --- --- --- 2.50 851.50 195 1,428 6.20 oc 640 0.00 2,025 0.00 0.00 --- 3.00 852.00 0.000 1,716 483 785 6.20 oc 2,810 0.00 --- 3.50 852.50 --- --- 1,999 0.000 928 875 3,738 6.20 oc 0.00 4.00 853.00 0.00 2,281 --- --- 1,069 0.000 4,807 1,385 851.00 4.50 853.50 0.00 2,559 0.00 1,209 --- --- 6,016 0.000 2.50 5.00 854.00 6.20 oc 2,837 0.00 1,348 0.00 7,364 -- --- --- Culvert/ Orifice Structures 3.00 2,810 Weir Structures 6.20 oc 0.08 is 0.00 --- [A] [B] [C] [PrfRsr] 0.080 [A] [B] [C] [D] Rise (in) = 15.00 2.00 5.00 0.00 Crest Len (ft) = 8.00 124.00 0.00 0.00 Span (in) = 15.00 2.00 12.00 0.00 Crest EI. (ft) = 853.00 853.50 0.00 0.00 No. Barrels = 1 1 4 0 Weir Coeff. = 3.33 3.33 3.33 3.33 Invert EI. (ft) = 847.00 851.33 852.00 0.00 Weir Type = 1 Ciplti --- - Length (ft) = 50.00 0.00 0.00 0.00 Multi -Stage = Yes No No No Slope (%) = 0.60 0.00 0.00 n/a N -Value = .013 .013 .013 n/a Orifice Coeff. = 0.60 0.60 0.60 0.60 Exfil.(in/hr) = 0.000 (by Contour) Multistage = n/a No No No TW Elev. (ft) = 0.00 Note: CulveNOrrifice outflows are analyzed under inlet uc) and outlet (oc) control. Weir risers checked for orifice conditions(ic) and submergence (s). Stage / Storage / Discharge Table Stage Storage Elevation CIvA CIvB CIvC PrfRsr WrA WrB WrC WrD Exfil User Total ft cuft ft cfs cfs cfs cfs cfs cfs cfs cfs cfs cfs cfs 0.00 0 849.00 0.00 0.00 0.00 --- 0.00 0.00 --- --- --- --- 0.000 0.50 195 849.50 6.20 oc 0.00 0.00 --- 0.00 0.00 --- --- --- --- 0.000 1.00 483 850.00 6.20 oc 0.00 0.00 --- 0.00 0.00 --- --- --- --- 0.000 1.50 875 850.50 6.20 oc 0.00 0.00 --- 0.00 0.00 --- --- --- --- 0.000 2.00 1,385 851.00 6.20 oc 0.00 0.00 --- 0.00 0.00 --- --- --- --- 0.000 2.50 2,025 851.50 6.20 oc 0.03 is 0.00 --- 0.00 0.00 -- -- --- --- 0.031 3.00 2,810 852.00 6.20 oc 0.08 is 0.00 --- 0.00 0.00 --- --- --- --- 0.080 3.50 3,738 852.50 6.20 oc 0.11 is 4.33 is --- 0.00 0.00 --- --- --- --- 4.443 4.00 4,807 853.00 6.20 oc 0.13 is 7.14 is --- 0.00 0.00 --- --- --- --- 7.273 4.50 6,016 853.50 9.42 oc 0.15 is 9.12 is --- 9.42 0.00 --- --- --- --- 18.69 5.00 7,364 854.00 14.69 oc 0.17 is 10.74 is --- 14.69s 145.99 --- --- --- --- 171.59 Larkin MF Development Project Report Section 6: Water Quality Calculations Permanent Detention Pond with Sand Filter 300 SAND FILTER Larkin M DDevelopment ITHE DRAINAGEAREA 1 Gminag number Total m_stl I tlserea sq l0 _ 2 - Break down of BUA in the drainag-:ana(b Ih all exisl g)_ Parking /tl Aew_ey sq (4 IB&B s! _ Total audasa water am. ma, If Total araingge area (sq ft) BRA .—period with estram, bewilderment (I ft) 45707 sf 45]0]8! -_Sidew_alk (se tt) -Roof (sq h) -Roadway an, fl) 1fi1]9 a( WO IT Ali it Proposed nee, ar Per<e nI BUA of drainage e 2231]4 49% -OlM1ec please specify in tM1e wmment has below (1,fl) Total BUA (sq X) Iran 9( COMPLIANCE WITH THE APPLICABLE STORMWATER PROGRAM - Roadway 1: X) 3]1 04 Slormweterpmgre tM1 SIV IPIaa 15200 sf Designralnfall depth (in) 15 in ____ ___ Percent RUA of reasons area 0.5% Minimum whimsy old (be H) Design Berne of 3CM(cu ft) ]WO cl SIR. of GENERAL MDC FROM 0211 .ID50 IXt IS the SCMszed fo freallM1 SWf Il sudawsa[bu luteol? #21s ho BCM Fowled on.1rear fa - 1¢e ls_ _ Vea__ No ]II ppm cable, w_iN lh 3CMb _dee_netl t I nlon? 0 Does the apprearperho access coarlywlhG=mlralMDC d? _ _. Yes Yes sh WM1at are the side slopes of the SCM(H:V)? 31 99 Once in. tlra_ge ea_e>_ImmQly with General MDC Ri Yws %i Doe In SCM M1eee rela_9 Il,g E nw_ells aromerestle slopes? #4 Am lh-Iy water., antl dide on, lowern preluded from a.bad (t0yeer dorm) 0515 them aabypass for XowS in ssof the Scoffs Mw? 1— No Yes Yes _ _ 101(the SCMis o_ ;ffleImill, tloes the pla{complYwlFG IMOCL0)?__ .y111s1harean O&MA endm.mle swth General MCCtt)_? (12)? Plan taut wmplies wieci Yes Yes Yes i6 WM1al is the methotllordewafenrg IM1e SCM (or mainlenenre? _ _ _ -13 Was I pum0 (Preferred) y13 Was IM1e SCM designetl by an NC lirsnsstl profes9oneP forma You SAND FILTER MDC FROM 02H .1056 #215 tM1e 9CMlo<eretl onorneer mnleminetatl ls? He Ue Poas IM1e damnlainance aam_pl wly tr nGenerIMDC(9i= 41 SHWfelavalion(fmst Xl Type of spend filter (open or cbsad) tlt ldosed describe if the Than will the precast or pour -in-place: .1 licensed lapofgraleelevedan(fmsf I N/A Oman I p3 Volume of stormwater From drainage area during resign slorm(cubic feel) 1f3 Tolelwlume that pan the sloretlabow the sediment and sena chambers (cubic feet) tl3 isthis _Island _011erdecigned_foattenuate peak flows' U3 Elewtion of the bypeaa daromi (Fms) p_3 Dascnba Free bypass tleviw al ]3)6 ci Yes di p2 Volume that can be retained in IM1e sediment chamber(cubic feet) G win thea be a Penn nem Stalin In. mdlmam charmers M unread of the sadimem chamber Qmsp 902 c! No Say it _ 1. four wide emeyency spillway d4 Po namg depth from the le, .111, 3s as to the bypass draw lfU 3fl #2 Areeoflhe aadlment<hamealrem amtew) 41951 aG...,,,a. the onalb-ism for reddened, new o we the .,it surface #t3 Was tee SCM utas signed by an NC licensed pro(assaonel? TZi Was an NC ll2 Physical depth of the sedimanlohember(In<M1as)3p #2 Pending depth In the sediment chamber. planus any Tendered bar (inches) in 03 in Ri,Rap apma tl6 Sandspedfcatica ormndcnamber M Elew_ oFttPol weir baboen criminals (bmsf &52X ASTM33 on equivaent #] DaSN armsane9Nrein prpe(incM1ed 15 in _ Y2 Volume marl per be retairztl in the and al ambar(cobic feel) 2218 cf AY Bodo. of the send chamber(fmsl)a4911 #2 an..I'maredchamberlsquembeef) lai M Wall the media he maintained to main at least two iheas Serlem-lthe sa ntl¢urfacea Yes #Pf,.-1 depth of the santl chember(anchea) 30 in #B is at least one<Iaii Pipe provaded at the low mar of each undeM2in line? Yes 92 Toning tleprhan IM1e aendeM1okill above any permanent prol(inches) Sit in #9 Will deanoa pi pas the <appetl? Yes ADDITIONAL INFORMATION III 0asctlbe tbeb sstlevrce: Please uss this s..a. -i td aaditaonal anformafion about the send firer that w u think is m levantto the redew'. 1209 at No 10 tooteviee emamordyspillway #2 ad I In pleasant (Ire #2 SpreAncerfare sedtamber r((rest( #2 Area oRM1e setlimenl chamberlWuarefeet) J— 2 rpnc L Y2 Ph amltlelh onhe sediment threat Pending depth in the sediment cM1ambep above any permanent pool (inches) 7800W2 If ]005 39 in Sit in d4 Pontlnb tlepmtmmnithe mfoofthe stin to lhebir the send purl) RIods, nbe Ne macaanism brdastebulin flowrtM1 .ntl sudece' RIPRapepron Y95ands acafineon lormntl cM1amber THE DRAINAGE AREA 2 Drainage area number 3 Break down of BUq in IM1e tlrainage aaa(both new and existing): ___,__ Total wasial..hand.... lsg fl)___ - Parking /dmeway (sg fl) 03e d Torslsuaeac walararechic,X)__ _ Tote) itch.... gree(a, (l) 3310. of 33190 sf -6itlawilk(agfl) -Roof me, ft) 1L903id BRA aswdicked with etistang developored lm ft) - Roadway 1: X) 3]1 04 PmPosed new BVA(yft) 15200 sf -Other gleam spedfyln Newmment box below (sq ll) ____ ___ Percent RUA of reasons area 0.5% TataI EUA (¢q fl) 152.5 COMPLIANCE. THE APPLICABLE STORMWATER PROGRAM Slormwaler ore amis)Inat eppl (please sped j Design reanfall depth lint 1.6 in Minimum wlume nli (<u ft) -kni whim. a1 SCM(cu fl, 9517 4 Iia cf GENERAL II FROM 0211.3050 111151.ST. ..red m load rhe SN from all eudance at hualabal? Yea d]If ep lirabla. wIf be, SCM be cleaned o. and, mn5ru<rian? 1 Yes #215 tM1e 9CMlo<eretl onorneer mnleminetatl ls? He Ue Poas IM1e damnlainance aam_pl wly tr nGenerIMDC(9i= l Ta¢ !p What am IM1e side stop.. of IM1e SCM(H V)? 3:1 %0 Doe, in. dream marl wmpl M_Ganeml MOM g)? Yes 0m the ECM I.R.er and hicann,aarrm, amem wallsorotherenylneeretlsiph, 15 ._Am #4 Arelhe_alets_out f.,fltl. inlocgstreamllim di fore eros.n(t0�ysens rm)? rat. ) # as oralwsi_he ee No Yes Yea III .1 ..a. is ona_5nglefamllylmnnplalee plat �Iyww General MDCSID)? #12 Ishere an O&M A re menl feel rod neswah GeneralMDC (11t an Ord Plansign that swnM1 General MDC ry214 Vas Ten Yen WhatI. lore. the SCM for me ntenan a #e What i. method SCM maintenafivelnce? Pump (pmfemd) #t3 Was tee SCM utas signed by an NC licensed pro(assaonel? TZi Was an NC ou You 02H.. SAND FILTER MDC FROM 02H .1056 E MDC #1 SHWTelevabonitmd) I WA #3 Volume of stormwater from bound, area during design sbrm kind. feat) paid, of #1 Ty of mne_fller (.man_orclo_m_d OWn W TOMl wlume that can be sraree abom Ne sediment and mnd ceembers (cubic feet e26gef _ #1 If cloche. demelbe YtM1a (leer will be paws orpour-In-plata'. rd ellimed a peek (lows? #3 is tbls.mnof Yes if3 Elsvataonof Nebypass((rest) thepappe device _ #11(domd, loP olgrete elevation ((rest) III 0asctlbe tbeb sstlevrce: r7 Volume that can be afainetl in IM1e mdamentchammrS._<ubcifeet__ _ _._ wool a maimed member? peter 1209 at No 10 tooteviee emamordyspillway #2 ad I In pleasant (Ire #2 SpreAncerfare sedtamber r((rest( #2 Area oRM1e setlimenl chamberlWuarefeet) J— 2 rpnc L Y2 Ph amltlelh onhe sediment threat Pending depth in the sediment cM1ambep above any permanent pool (inches) 7800W2 If ]005 39 in Sit in d4 Pontlnb tlepmtmmnithe mfoofthe stin to lhebir the send purl) RIods, nbe Ne macaanism brdastebulin flowrtM1 .ntl sudece' RIPRapepron Y95ands acafineon lormntl cM1amber 3ft _ Kt LM atlonorbpolwear between chambers Imsl 62 Volume that can ba retained in the send chamber (cubic mi M6ft 20504 ASTM33 or equivalent IX2 Bonam of the mM<hands, lfmsq .2 ft #] Depth above ooaent pips(inches) is an AS Area of the bona chamber mel feet 11605 ad ..It the mead. bed nee.¢rei, at Wenches per hoar at send sueace? raz #2 shot depth of sena rnamberinch r L_—______ 39m .laa Is.. pli me—l_plpe p—dd a tea mw pram o_ aecnundena2lnoma? yen #z pomemg aapmmma.ama mambecme. anr permamadpaolfnmea) 36m _ _ _ #s wiu daamaaePipe. be So card? I vas ADDITIONAL INFORMATION Plead im, this space protide an anderand information abouttM13 sandfloor that Vanthlnk is deadentl the have -to Sand Filler 1 1:53 PM 5/5/2017 Larkin MF Development Comprehensive SWPPP Pre & Post Analysis Section 3: Pre & Post Analysis Summary Larkin Statesville, North Carolina Project Number: 2382 October 4, 2016 POINT OF ANALYSIS - NORTH WEST INTO EXISTING STORM PIPE Pre vs. Post Hvdrologv Pre vs. Post Hvdrolo Area 2 YR 10 YR 25 YR 100 YR Pre Area #2 (acres) Post -Development Flow (cfs) Post Area #1 1.18 0.07 0.66 1.46 2.29 Pre -Development Flow (cfs) Pre Area #1 3.86 9.21 17.55 22.95 32.05 Post -Development Flow (cfs) Post Area #2 1.05 0.54 4.80 6.14 6.77 Post Area #3 0.77 0.09 2.54 4.39 6.06 Post Bypass #4 1.08 1.72 3.82 5.25 8.30 Post Bypass #5 0.66 1.60 3.06 4.01 7.57 Combined Area 3.56 3.40 13.34 19.49 28.35 POINT OF ANALYSIS - SOUTH WEST INTO EXISTING DITCH Pre vs. Post Hvdrolo Area 2 YR 10 YR 25 YR 100 YR (acres) Pre -Development Flow (cfs) Pre Area #2 1.20 2.23 4.87 6.64 9.70 Post -Development Flow (cfs) Post Area #1 1.18 0.07 0.66 1.46 2.29 Larkin MF Development Comprehensive SWPPP (C-SWPPP) Section 3: Pre & Post Analysis Pre -Development Curve Numbers Pre Curve Numbers Larkin Statesville, North Carolina Project Number: 2382 October 24, 2016 COMPOSITE SCS RUNOFF CURVE NUMBERS 24 Hour Storm Event Pre -Development Area #1 Soil Type: Cecil sandy clay loam, Cecil -Urban Land Complex - HSG "B" Total Drainage Area = 3.86 ac. Paved Roads/Sidewalk/Structures 1.60 ac. CN= 98 PA06MOVI_RF1 CN= 60 0.00 ac. Goad Grass (>75% coverage) 2.26 ac. CN= 61 Newly Graded Composite CN 76.34 ac. Larkin Statesville, North Carolina Project Number: 2382 October 24, 2016 COMPOSITE SCS RUNOFF CURVE NUMBERS 24 Hour Storm Event Pre -Development Area #2 Soil Type: Cecil sandy clay loam, Cecil -Urban Land Complex - HSG "B" Total Drainage Area = 1.20 ac. Paved Roads/Sidewalk/Structures 0.25 ac. CN= 98 rr.•INOI& Er CN= 60 0.00 ac. Good Grass (>75% coverage) 0.95 ac. Newly Graded CN= 61 CN= 86 Composite CN 68.71 0.00 ac. Larkin MF Development Comprehensive SWPPP Section 3: Pre & Post Analysis Post -Development Curve Numbers Post Curve Numbers Larkin Statesville, North Carolina Project Number: 2382 October 24, 2016 COMPOSITE SCS RUNOFF CURVE NUMBERS 24 Hour Storm Event Post Development Area #1 Soil Type: Cecil sandy clay loam, Cecil -Urban Land Complex - HSG "B" Total Drainage Area = 1.18 ac. Paved Roads/Sidewalk/Structures 0.55 ac. CN= 98 Wooded Area CN= 60 0.00 ac. Good Grass (>75% coverage) 0.63 ac. Newly Graded CN= 86 Composite CN 78.25 11111O)FT4 Larkin Statesville, North Carolina Project Number: 2382 October 24, 2016 COMPOSITE SCS RUNOFF CURVE NUMBERS 24 Hour Storm Event Post Development Area #2 Soil Type: Cecil sandy clay loam, Cecil -Urban Land Complex - HSG "B" Total Drainage Area = 1.05 ac. Paved Roads/Sidewalk/Structures 0.51 ac. CN= 98 Wooded Area CN= 60 0.00 ac. Good Grass (>75% coverage) 0.54 ac. Newly Graded CN= 61 • :c Composite CN 78.97 111111411104 Larkin Statesville, North Carolina Project Number: 2382 October 24, 2016 COMPOSITE SCS RUNOFF CURVE NUMBERS 24 Hour Storm Event Post Development Area #3 Soil Type: Cecil sandy clay loam, Cecil -Urban Land Complex - HSG "B" Total Drainage Area = 0.77 ac. Paved Roads/Sidewalk/Structures 0.35 ac. CN= 98 Wooded Area CN= 60 14110104 Good Grass (>75% coverage) 0.42 ac. CN= 61 Newly Graded CN= 86 Composite CN 77.82 0.00 ac. Larkin Statesville, North Carolina Project Number: 2382 October 24, 2016 40L51��bY11_Y�Y:ip�[�7��fltiI79�DJiril=l�� 24 Hour Storm Event Post Development Bypass Area #4 Soil Type: Cecil sandy clay loam, Cecil -Urban Land Complex - HSG "B" Total Drainage Area = 1.14 ac. Paved Roads/Sidewalk/Structures 0.23 ac. CN= 98 Wooded Area CN= 60 0.00 ac. Good Grass (>75% coverage) 0.91 ac. CN= 61 Newly Graded :IMM -11 Composite CN 68.46 0.00 ac. Larkin Statesville, North Carolina Project Number: 2382 October 24, 2016 COMPOSITE SCS RUNOFF CURVE NUMBERS 24 Hour Storm Event Post Development Bypass Area #5 Soil Type: Cecil sandy clay loam, Cecil -Urban Land Complex - HSG "B" Total Drainage Area = 0.92 ac. Paved Roads/Sidewalk/Structures 0.32 ac. CN= 98 n0000iIrix1 CN= 60 0.00 ac. Good Grass (>75% coverage) 0.60 ac. Newly Graded CN= 61 CN= 86 Composite CN 73.87 0.00 ac. / \ Mo § § § 666 !§§ § §§ 81 !§! §§ \ E - [( §>¢E�\ »§ §?2 �j2;oz /! :E _»�®:«§ r.``\\`w° mo w,W<)§:�|§/ / 666 81 !§! §§ E - [( §>¢E�\ »§ §?2 �j2;oz /! :E _»�®:«§ r.``\\`w° mo w,W<)§:�|§/ / Fk !§§ ai | !§§ / ( §6(E;r ,z |E E;/=#7lwwz u[Ey®§ !(»�§§\j M go ;,0<3:m uu:i4, / ®<\�� (( ( ®W.08 140 �§/§}3: <zw � u02 / \�r[( \( ®§§\k}\§>o \'Z w§ !m§ \w QH!!#l,ua I \ ! \ OT 0 [a ^39§22§ ! \ w E[ \( §w maa m o® °. W,Goz!\)4 \)\((\\\\\\\ / e( E zk (§ !OEE>W ®# |{ E;;;;lEw;: 222,:2!§®:®§ //0(()\\§\\)) / § ^39§22§ w E[ \( §w maa m o® °. W,Goz!\)4 \)\((\\\\\\\ / e( E zk (§ !OEE>W ®# |{ E;;;;lEw;: 222,:2!§®:®§ //0(()\\§\\)) / § / \ | LgLtffE [! }/ |\«E§\§���§>| !Hbwoo §)EWLQSj>Zzww m!>tl,W.0 <$- / a j ; !§§ § §§ §§§ § §§ ; ((E( /) - [!®[°[ (> §M z -z ()§)\ !u®�§ \j/LQgWw|!/M !!!«I,:u�!■� � / §§§ § §§ ((E( /) - [!®[°[ (> §M z -z ()§)\ !u®�§ \j/LQgWw|!/M !!!«I,:u�!■� � / / , \ ai / Larkin MF Development Comprehensive SWPPP 2 & 10 -year Storm Event Hydrograph Analysis Section 3: Pre & Post Analysis Hydrograph Hydrograph Summary Re p9yd aflow Hydrographs Extension for AutoCAD® Civil 3D® 2016 by Autodesk, Inc. v10.5 Hyd. No. Hydrograph type (origin) Peak flow (cfs) Time interval (min) Time to Peak (min) Hyd. volume (cuft) Inflow hyd(s) Maximum elevation (ft) Total strge used (cuft) Hydrograph Description 1 SCS Runoff 9.206 1 720 20,847 ------ ------ ------ Pre -Development Area #1 2 SCS Runoff 2.233 1 718 4,592 ------ ------ ----- Pre -Development Area #2 3 SCS Runoff 3.573 1 718 7,181 ----- ----- ------ Post Development Area #1 4 SCS Runoff 3.260 1 718 6,558 --•-- ----- ------ Post Development Area #2 5 SCS Runoff 2.301 1 718 4,622 ----- ------ ------ Post Development Area #3 6 SCS Runoff 1.717 1 719 3,739 ------ ------ ----- Post Development Bypass #4 7 SCS Runoff 1.596 1 719 3,366 ----- ------ ------ Post Development Bypass Area #5 8 Reservoir 0.068 1 1023 5,112 3 867.03 5,074 BMP Wetpond #100 9 Reservoir 0.541 1 728 4,722 4 852.10 3,002 BMP Sand Filter #200 10 Reservoir 0.090 1 826 3,293 5 864.83 2,571 BMP Sand Filter#300 11 Combine 3.395 1 719 15,120 6,7,9, ------ ------ Post Development Area#1 10 Pre vs Post with SF.gpw Return Period: 2 Year Friday, 05 / 5 / 2017 2 Hydrograph Report HydraFlow Hydrographs Extension for AutoCAD® Civil 3D@2016 by Autodesk, Inc. v10.5 Friday, 05 15 / 2017 Hyd. No. 1 Pre -Development Area #1 Hydrograph type = SCS Runoff Peak discharge = 9.206 cfs Storm frequency = 2 yrs Time to peak = 720 min Time interval = 1 min Hyd. volume = 20,847 cuft Drainage area = 3.860 ac Curve number = 76.3 Basin Slope = 0.0% Hydraulic length = 0 ft Tc method = User Time of conc. (Tc) = 9.10 min Total precip. = 3.64 in Distribution = Type II Storm duration = 24 hrs Shape factor = 484 Q (cfs) 10.00 :M .M 2.00 0.00 0 120 240 Hyd No. 1 Pre -Development Area #1 Hyd. No. 1 -- 2 Year 360 480 600 720 840 Q (cfs) 10.00 MI MI 4.00 2.00 0.00 960 1080 1200 1320 1440 1560 Time (min) 3 Hydrograph Report HydraFlow Hydrographs Extension for AutoCAD® Civil 3D® 2016 by Autodesk, Inc. v10.5 Friday, 05 / 5 / 2017 Hyd. No. 2 Pre -Development Area #2 Hydrograph type = SCS Runoff Peak discharge = 2.233 cfs Storm frequency = 2 yrs Time to peak = 718 min Time interval = 1 min Hyd. volume = 4,592 cuft Drainage area = 1.200 ac Curve number = 68.7 Basin Slope = 0.0% Hydraulic length = 0 ft Tc method = User Time of conc. (Tc) = 5.00 min Total precip. = 3.64 in Distribution = Type II Storm duration = 24 hrs Shape factor = 484 Pre -Development Area #2 Q (cfs) Hyd. No. 2 -- 2 Year 3.00 2.00 1.00 CTdTb� Q (cfs) 3.00 2.00 1.00 0 120 240 360 480 600 720 840 960 1080 1200 1320 1440 1560 Hyd No. 2 Time (min) 4 Hydrograph Report Hydraflow Hydrographs Extension for AutoCAD® Civil 3D® 2016 by Autodesk, Inc. v10.5 Friday, 05 / 5 / 2017 Hyd. No. 3 Post Development Area #1 Hydrograph type = SCS Runoff Peak discharge = 3.573 cfs Storm frequency = 2 yrs Time to peak = 718 min Time interval = 1 min Hyd. volume = 7,181 cuft Drainage area = 1.180 ac Curve number = 78.3 Basin Slope = 0.0% Hydraulic length = 0 ft Tc method = User Time of conc. (Tc) = 5.00 min Total precip. = 3.64 in Distribution = Type II Storm duration = 24 hrs Shape factor = 484 Q (Cfs) 4.00 3.00 r 11 1.00 hidTt� Post Development Area #1 Hyd. No. 3 -- 2 Year Q (Cfs) 4.00 3.00 2.00 1.00 Mww 0 120 240 360 480 600 720 840 960 1080 1200 1320 1440 1560 Hyd No. 3 Time (min) Hydrograph Report 5 Hydraflow Hydrographs Extension for AutoCAD® Civil 3D® 2016 by Autodesk, Inc. 00.5 Friday, 05 / 5 / 2017 Hyd. No. 4 Post Development Area #2 Hydrograph type = SCS Runoff Peak discharge = 3.260 cfs Storm frequency = 2 yrs Time to peak = 718 min Time interval = 1 min Hyd. volume = 6,558 cuft Drainage area = 1.050 ac Curve number = 78.9 Basin Slope = 0.0% Hydraulic length = Oft Tc method = User Time of conc. (Tc) = 5.00 min Total precip. = 3.64 in Distribution = Type II Storm duration = 24 hrs Shape factor = 484 Post Development Area #2 Q (cfs) Hyd. No. 4 -- 2 Year Q (cfs) 4.00 4.00 3.00 3.00 2.00 2.00 1.00 1.00 0.00 0.00 0 120 240 360 480 600 720 840 960 1080 1200 1320 1440 1560 Hyd No. 4 Time (min) Hydrograph Report 6 Hydraflow Hydrographs Extension for AutoCAD® Civil 3D® 2016 by Autodesk, Inc. v10.5 Friday, 05 / 5 / 2017 Hyd. No. 5 Post Development Area #3 Hydrograph type = SCS Runoff Peak discharge = 2.301 cfs Storm frequency = 2 yrs Time to peak = 718 min Time interval = 1 min Hyd. volume = 4,622 cuft Drainage area = 0.790 ac Curve number = 77.4 Basin Slope = 0.0% Hydraulic length = 0 ft Tc method = User Time of conc. (Tc) = 6.60 min Total precip. = 3.64 in Distribution = Type II Storm duration = 24 hrs Shape factor = 484 Post Development Area #3 Q (cfs) Q (cfs) Hyd. No. 5 -- 2 Year 3.00 3.00 2.00 2.00 1.00 1.00 0.00 - 0.00 0 120 240 360 480 600 720 840 960 1080 1200 1320 1440 1560 Hyd No. 5 Time (min) 7 Hydrograph Report Hydraflow Hydrographs Extension for AutoCAD® Civil 3D® 2016 by Autodesk, Inc. 00.5 Friday, 05 / 5 / 2017 Hyd. No. 6 Post Development Bypass #4 Hydrograph type = SCS Runoff Peak discharge = 1.717 cfs Storm frequency = 2 yrs Time to peak = 719 min Time interval = 1 min Hyd. volume = 3,739 cuft Drainage area = 1.080 ac Curve number = 67.9 Basin Slope = 0.0% Hydraulic length = 0 ft Tc method = User Time of conc. (Tc) = 8.10 min Total precip. = 3.64 in Distribution = Type II Storm duration = 24 hrs Shape factor = 484 Post Development Bypass #4 Q (cfs) Hyd. No. 6 -- 2 Year 2.00 1.00 r*dTd1 Q (Cfs) 2.00 1.00 HT1 0 120 240 360 480 600 720 840 960 1080 1200 1320 1440 1560 Hyd No. 6 Time (min) Hydrograph Report HydraFlow Hydrographs Extension for AutoCAD® Civil 3D® 2016 by Autodesk, Inc. 00.5 Hyd. No. 7 Post Development Bypass Area #5 Hydrograph type = SCS Runoff Peak discharge Storm frequency = 2 yrs Time to peak Time interval = 1 min Hyd. volume Drainage area = 0.660 ac Curve number Basin Slope = 0.0% Hydraulic length Tc method = User Time of conc. (Tc) Total precip. = 3.64 in Distribution Storm duration = 24 hrs Shape factor Q (cfs) 2.00 1.00 0.00 0 120 240 Hyd No. 7 Post Development Bypass Area #5 Hyd. No. 7 -- 2 Year 360 480 600 720 U Friday, 05 / 5 / 2017 = 1.596 cfs = 719 min = 3,366 cuft = 75.6 = Oft = 7.30 min = Type II = 484 Q (cfs) 2.00 1.00 0.00 840 960 1080 1200 1320 1440 1560 Time (min) 9 Hydrograph Report Hydraflow Hydrographs Extension for AutoCAD® Civil 3D® 2016 by Autodesk, Inc. 00.5 Friday, 05 15 / 2017 Hyd. No. 8 3000 BMP Wetpond #100 Time (min) Hydrograph type = Reservoir Peak discharge = 0.068 cfs Storm frequency = 2 yrs Time to peak = 1023 min Time interval = 1 min Hyd. volume = 5,112 cuft Inflow hyd. No. = 3 - Post Development Area #Max. Elevation = 867.03 ft Reservoir name = BMP Wetpond #100 Max. Storage = 5,074 cuft Storage Indication method used. Q (cfs) 4.00 3.00 2.00 Orm BMP Wetpond #100 Hyd. No. 8 -- 2 Year Q (cfs) 4.00 OR 2.00 1.00 IWIT7 0 300 600 900 1200 1500 1800 2100 2400 2700 3000 Time (min) — Hyd No. 8 —Hyd No. 3 Total storage used = 5,074 tuft Pond Report 10 Hydraflow Hydrographs Extension for AutoCAD® Civil 3D® 2016 by Autodesk, Inc. v10.5 Friday, 05 / 5 / 2017 Pond No. 1 - BMP Wetpond #100 Pond Data Contours -User-defined contour areas. Conic method used for volume calculation. Begining Elevation = 866.00 ft Stage / Storage Table Stage (ft) Elevation (ft) Contour area (sqft) Incr. Storage (cuft) Total storage (cult) 0.00 866.00 4,093 0 0 0.50 866.50 5,005 2,270 2,270 1.00 867.00 5,575 2,643 4,914 2.00 868.00 6,767 6,161 11,075 3.00 869.00 8,025 7,386 18,461 4.00 870.00 9,367 8,686 27,148 5.00 871.00 10,026 9,694 36,841 Culvert / Orifice Structures Weir Structures [A] [B] [C] [PrtRsr] [A] [B] [C] [D] Rise (in) = 15.00 1.25 6.00 0.00 Crest Len (ft) = 10.00 173.00 0.00 0.00 Span (in) = 15.00 1.25 12.00 0.00 Crest EI. (ft) = 869.00 870.00 0.00 0.00 No. Barrels = 1 1 1 0 Weir Coeff. = 3.33 3.33 3.33 3.33 Invert EI. (ft) = 866.00 866.00 867.00 0.00 Weir Type = 1 Ciplti --- --- Length (ft) = 63.00 0.00 0.00 0.00 Multi -Stage = Yes No No No Slope (%) = 1.59 0.00 0.00 n/a N -Value = .013 .013 .013 n/a Orifice Coeff. = 0.60 0.60 0.60 0.60 Exfil.(in/hr) = 0.000 (by Contour) Multi -Stage = n/a No No No TW Elev. (ft) = 0.00 Note:Culvert/Orifice ouflows are analyzed under inlet(ic) and outlet(oc) control. Weir risers checked for orifice conditions(ic) and submergence (a). Stage / Storage I Discharge Table Stage Storage Elevation Clv A Clv B CIV C PrtRsr Wr A Wr B WrC Wr D Exfil User Total ft cuft ft cfs cfs cfs cfs cfs cfs cfs cfs cfs cfs cfs 0.00 0 866.00 0.00 0.00 0.00 --- 0.00 0.00 --- --- - --- 0.000 0.50 2,270 866.50 0.00 0.03 is 0.00 -- 0.00 0.00 --- -- -- --- 0.027 1.00 4,914 867.00 0.00 0.04 is 0.00 --- 0.00 0.00 --- --- - --- 0.040 2.00 11,075 868.00 0.00 0.06 is 2.08 is --- 0.00 0.00 --- --- -- --- 2.142 3.00 18,461 869.00 0.00 0.07 is 3.18 is --- 0.00 0.00 --- --- --- --- 3.255 4.00 27,148 870.00 10.80 is 0.08 is 3.99 is --- 10.79s 0.00 --- --- -- --- 14.86 5.00 36,841 871.00 12.35 is 0.09 io 4.66 is -- 12.30s 576.09 --- -- - --- 593.14 Hydrograph Report 11 Hydraflow Hydrographs Extension for AutoCAD® Civil 3D@2016 by Autodesk, Inc. v10.5 Friday, 05 15 / 2017 Hyd. No. 9 BMP Sand Filter #200 Hydrograph type = Reservoir Peak discharge = 0.541 cfs Storm frequency = 2 yrs Time to peak = 728 min Time interval = 1 min Hyd. volume = 4,722 cuft Inflow hyd. No. = 4 - Post Development Area #24ax. Elevation = 852.10 ft Reservoir name = Sand Filter #200 Max. Storage = 3,002 cuft Storage Indication method used Q (cfs) 4.00 3.00 2.00 1.00 BMP Sand Filter #200 Hyd. No. 9 -- 2 Year 0.00 0 180 360 540 720 900 1080 1260 1440 1620 Hyd No. 9 — Hyd No. 4 ® Total storage used = 3,002 cuft Q (cfs) 4.00 3.00 2.00 1.00 ---t 0.00 1800 Time (min) Pond Report 12 Hydraflow Hydrographs Extension for AutoCAD® Civil 3D® 2016 by Autodesk, Inc. v10.5 Friday, 05 / 5 / 2017 Pond No. 2 - Sand Filter #200 Pond Data Contours -User-defined contour areas. Conic method used for volume calculation. Begining Elevation = 849.00 ft Stage / Storage Table Stage (ft) Elevation (ft) Contour area (sgft) Incr. Storage (cuft) Total storage (cuft) 0.00 849.00 302 0 0 0.50 849.50 486 195 195 1.00 850.00 670 288 483 1.50 850.50 905 392 875 2.00 851.00 1,139 510 1,385 2.50 851.50 1,428 640 2,025 3.00 852.00 1,716 785 2,810 3.50 852.50 1,999 928 3,738 4.00 853.00 2,281 1,069 4,807 4.50 853.50 2,559 1,209 6,016 5.00 854.00 2,837 1,348 7,364 Culvert I Orifice Structures Weir Structures [A] [B] [C] [PrtRsr] [A] [B] [C] [D] Rise (in) = 15.00 2.00 5.00 0.00 Crest Len (ft) = 8.00 124.00 0.00 0.00 Span (in) = 15.00 2.00 12.00 0.00 Crest El. (ft) = 853.00 853.50 0.00 0.00 No. Barrels = 1 1 4 0 Weir Coeff. = 3.33 3.33 3.33 3.33 Invert EI. (ft) = 847.00 851.33 852.00 0.00 Weir Type = 1 Ciplti --- --- Length (ft) = 50.00 0.00 0.00 0.00 Multi -Stage = Yes No No No Slope (%) = 1.20 0.00 0.00 n/a N -Value = .013 .013 .013 n/a Orifice Coeff. = 0.60 0.60 0.60 0.60 Exfil.(in/hr) = 0.000 (by Contour) Multi -Stage = n/a No No No TW Elev. (ft) = 0.00 NoteCulvervonfice oudlows are analyzed under inlet tc) and outlet (cc) control. Weir risers checked for crifiw conditions (c) and submergence (a). Stage I Storage / Discharge Table Stage Storage Elevation Civ A Clv B CIV C PrtRsr Wr A Wr B W r C Wr D Exfil User Total ft cuft ft cfs cfs cfs cfs cfs cfs cfs cfs cfs cfs cfs 0.00 0 849.00 0.00 0.00 0.00 --- 0.00 0.00 --- --- --- --- 0.000 0.50 195 849.50 6.93 is 0.00 0.00 --- 0.00 0.00 --- --- --- --- 0.000 1.00 483 850.00 6.93 is 0.00 0.00 --- 0.00 0.00 --- --- --- --- 0.000 1.50 875 850.50 6.93 is 0.00 0.00 --- 0.00 0.00 --- --- --- --- 0.000 2.00 1,385 851.00 6.93 is 0.00 0.00 --- 0.00 0.00 --- --- --- --- 0.000 2.50 2,025 851.50 6.93 is 0.03 is 0.00 --- 0.00 0.00 --- --- --- --- 0.031 3.00 2,810 852.00 6.93 is 0.08 is 0.00 -- 0.00 0.00 - --- --- --- 0.080 3.50 3,738 852.50 6.93 is 0.11 is 4.33 is --- 0.00 0.00 --- -- -- --- 4.443 4.00 4,807 853.00 6.93 is 0.13 is 7.14 is --- 0.00 0.00 --- --- --- --- 7.273 4.50 6,016 853.50 9.42 is 0.15 is 9.12 is --- 9.42 0.00 --- --- --- --- 18.69 5.00 7,364 854.00 14.74 is 0.17 is 10.74 is --- 14.74s 145.99 --- --- --- --- 171.64 Hydrograph Report 13 Hydraflow Hydrographs Extension for AutoCAD® Civil 3D® 2016 by Autodesk, Inc. v10.5 Friday, 05 15 / 2017 Hyd. No. 10 BMP Sand Filter#300 Hydrograph type = Reservoir Peak discharge = 0.090 cfs Storm frequency = 2 yrs Time to peak = 826 min Time interval = 1 min Hyd. volume = 3,293 cuft Inflow hyd. No. = 5 -Post Development Area #&lax. Elevation = 864.83 ft Reservoir name = Sand Filter #300 Max. Storage = 2,571 cuft Storage Indication method used Q (cfs) 3.00 2.00 1.00 BMP Sand Filter #300 Hyd. No. 10 -- 2 Year 0.00 - 0 240 480 720 960 1200 1440 1680 1920 2160 Hyd No. 10 — Hyd No. 5 Total storage used = 2,571 cult Q (cfs) 3.00 2.00 1.00 ---1- 0.00 2400 Time (min) Pond Report 14 Hydragow Hydrographs Extension for AutoCAD® Civil 3002016 by Autodesk, Inc. v10.5 Friday, 05 15 / 2017 Pond No. 3 - Sand Filter #300 Pond Data Contours -User-defined contour areas. Conic method used for volume calculation. Begining Elevation = 862.00 ft Stage / Storage Table Stage (ft) Elevation (ft) Contour area (sqft) Incr. Storage (cuft) Total storage (cuft) 0.00 862.00 178 0 0 0.50 862.50 393 139 139 1.00 863.00 608 248 388 1.50 863.50 902 375 763 2..00 864.00 1,195 522 1,285 2.50 864.50 1,597 696 1,981 3.00 865.00 1,938 882 2,863 3.50 865.50 2,252 1,046 3,909 4.00 866.00 2,566 1,204 5,113 4.50 866.50 2,979 1,385 6,498 5.00 867.00 3,189 1,542 8,039 Culvert/ Orifice Structures Weir Structures [A] [Bl [C] [PrtRsr] [A] [B] [C] ID] Rise (in) = 15.00 2.00 5.00 0.00 Crest Len (ft) = 8.00 162.00 0.00 0.00 Span (in) = 15.00 2.00 12.00 0.00 Crest EI. (ft) = 866.00 866.50 0.00 0.00 No. Barrels = 1 1 4 0 Weir Coeff. = 3.33 3.33 3.33 3.33 Invert EI. (ft) = 860.00 864.02 865.00 0.00 Weir Type = 1 Ciplti --- --- Length (ft) = 125.00 0.00 0.00 0.00 Multi -Stage = Yes No No No Slope (%) = 1.11 0.00 0.00 n/a N -Value = .013 .013 .013 n/a Orifice Coeff. = 0.60 0.60 0.60 0.60 Exfil.(in/hr) = 0.000 (by Contour) Multi -Stage = n/a No No No TW Elev. (ft) = 0.00 Note:Culvert/Orifce outfows are analyzed under inlet(ic) and outlet (oc) control. Weir risers checked for orifce conditions(ic) and submergence (a). Stage / Storage / Discharge Table Stage Storage Elevation Clv A Clv B CIV C PrtRsr Wr A Wr B Wr C Wr D Exfil User Total ft cult ft cfs cfs cfs cfs cfs cfs cfs cfs cfs cfs cfs 0.00 0 862.00 0.00 0.00 0.00 --- 0.00 0.00 --- --- --- --- 0.000 0.50 139 862.50 6.88 oc 0.00 0.00 --- 0.00 0.00 --- --- --- --- 0.000 1.00 388 863.00 6.88 oc 0.00 0.00 --- 0.00 0.00 --- --- --- -- 0.000 1.50 763 863.50 6.88 oc 0.00 0.00 --- 0.00 0.00 --- --- --- --- 0.000 2.00 1,285 864.00 6.88 oc 0.00 0.00 --- 0.00 0.00 --- --- --- --- 0.000 2.50 1,981 864.50 6.88 oc 0.07 is 0.00 --- 0.00 0.00 --- --- --- -- 0.066 3.00 2,863 865.00 6.88 oc 0.10 is 0.00 --- 0.00 0.00 --- --- --- --- 0.099 3.50 3,909 865.50 6.88 oc 0.12 is 4.33 is --- 0.00 0.00 -- --- --- --- 4.458 4.00 5,113 866.00 6.88 oc 0.14 is 7.14 is --- 0.00 0.00 --- --- -- --- 7.285 4.50 6,498 866.50 9.42 oc 0.16 is 9.12 is -- 9.42 0.00 --- --- -- --- 18.70 5.00 8,039 867.00 12.49 oc 0.18 is 10.74 is --- 12.49s 190.73 --- --- -- --- 214.13 Hydrograph Report 15 Hydraflow Hydrographs Extension for AutoCAD® Civil 3D® 2016 by Autodesk, Inc. 00.5 Friday, 05 / 5 / 2017 Hyd. No. 11 Post Development Area #1 Hydrograph type = Combine Peak discharge = 3.395 cfs Storm frequency = 2 yrs Time to peak = 719 min Time interval = 1 min Hyd. volume = 15,120 cuft Inflow hyds. = 6, 7, 9, 10 Contrib. drain. area = 1.740 ac Q (cfs) 4.00 3.00 2.00 1.00 Post Development Area #1 Hyd. No. 11 -- 2 Year 0.00 0 180 360 540 720 900 1080 Hyd No. 11 — Hyd No. 6 — Hyd No. 7 — Hyd No. 10 1260 1440 — Hyd No. 9 Q (cfs) 4.00 3.00 2.00 1.00 IIMMM�- 0.00 1620 Time (min) U -j Hydrograph Summary Re pl9yd aflow Hydrographs Extension for AutoCAD® Civil 3D® 2016 by Autodesk, Inc. v10.5 Hyd. No. Hydrograph type (origin) Peak flow (cfs) Time interval (min) Time to Peak (min) Hyd. volume (cuft) Inflow hyd(s) Maximum elevation (ft) Total strge used (cuft) Hydrograph Description 1 SCS Runoff 17.55 1 719 39,754 ------ ------ ------ Pre -Development Area #1 2 SCS Runoff 4.867 1 718 9,773 ------ ----- ------ Pre -Development Area #2 3 SCS Runoff 6.534 1 718 13,349 ------ ------ --- Post Development Area #1 4 SCS Runoff 5.910 1 718 12,100 ------ ------ ------ Post Development Area #2 5 SCS Runoff 4.267 1 718 8,689 ------ ------ ------ Post Development Area #3 6 SCS Runoff 3.823 1 719 8,064 ------ ------ ------ Post Development Bypass #4 7 SCS Runoff 3.057 1 718 6,479 ----- ------ ----- Post Development Bypass Area #5 8 Reservoir 0.658 1 744 11,207 3 867.32 6,870 BMP Wetpond #100 9 Reservoir 4.800 1 720 10,264 4 852.55 3,844 BMP Sand Filter#200 10 Reservoir 2.536 1 722 7,360 5 865.32 3,524 BMP Sand Filter#300 11 Combine 13.34 1 720 32,167 6, 7, 9, ------ ----- Post Development Area #1 10 Pre vs Post with SF.gpw Return Period: 10 Year Friday, 05 / 5 / 2017 Hydrograph Report 17 Hydraflow Hydrographs Extension for AutoCAD® Civil 3D® 2016 by Autodesk, Inc. v10.5 Friday, 05 / 5 / 2017 Hyd. No. 1 Pre -Development Area #1 Hydrograph type = SCS Runoff Peak discharge = 17.55 cfs Storm frequency = 10 yrs Time to peak = 719 min Time interval = 1 min Hyd. volume = 39,754 cuft Drainage area = 3.860 ac Curve number = 76.3 Basin Slope = 0.0% Hydraulic length = 0 ft Tc method = User Time of conc. (Tc) = 9.10 min Total precip. = 5.33 in Distribution = Type II Storm duration = 24 hrs Shape factor = 484 Q (cfs) 18.00 15.00 12.00 • M .10 3.00 Pre -Development Area #1 Hyd. No. 1 -- 10 Year Q (cfs) 18.00 15.00 12.00 M . IX 3.00 0.00 1 1 1—ice1 1 1 0.00 0 120 240 360 480 600 720 840 960 1080 1200 1320 1440 1560 — Hyd No. 1 Time (min) Hydrograph Report 18 HydraFlow Hydrographs Extension for AutoCAD® Civil 3D@2016 by Autodesk, Inc. v10.5 Friday, 05 / 5 / 2017 Hyd. No. 2 Pre -Development Area #2 Hydrograph type = SCS Runoff Peak discharge = 4.867 cfs Storm frequency = 10 yrs Time to peak = 718 min Time interval = 1 min Hyd. volume = 9,773 cuft Drainage area = 1.200 ac Curve number = 68.7 Basin Slope = 0.0% Hydraulic length = 0 ft Tc method = User Time of conc. (Tc) = 5.00 min Total precip. = 5.33 in Distribution = Type II Storm duration = 24 hrs Shape factor = 484 Pre -Development Area #2 Q (cfs) Hyd. No. 2 -- 10 Year 5.00 GXIIIIH ci1 2.00 1.00 MM Q (cfs) 5.00 4.00 3.00 2.00 1.00 wM 0 120 240 360 480 600 720 840 960 1080 1200 1320 1440 1560 — Hyd No. 2 Time (min) Hydrograph Report 19 Hydraflow Hydrographs Extension for AutoCAD® Civil 3D® 2016 by Autodesk, Inc. 00.5 Friday, 05 / 5 / 2017 Hyd. No. 3 Post Development Area #1 Hydrograph type = SCS Runoff Peak discharge = 6.534 cfs Storm frequency = 10 yrs Time to peak = 718 min Time interval = 1 min Hyd. volume = 13,349 cuft Drainage area = 1.180 ac Curve number = 78.3 Basin Slope = 0.0% Hydraulic length = 0 ft Tc method = User Time of conc. (Tc) = 5.00 min Total precip. = 5.33 in Distribution = Type II Storm duration = 24 hrs Shape factor = 484 Post Development Area #1 Q (cfs) Hyd. No. 3 -- 10 Year 7.00 6.00 5.00 4.00 3.00 2.00 1.00 000 Q (cfs) 7.00 6.00 5.00 4.00 3.00 2.00 1.00 000 0 120 240 360 480 600 720 840 960 1080 1200 1320 1440 Hyd No. 3 Time (min) Hydrograph Report 20 Hydraflow Hydrographs Extension for AutoCAD® Civil 3D@2016 by Autodesk, Inc. v10.5 Friday, 05 / 5 / 2017 Hyd. No. 4 Post Development Area #2 Hydrograph type = SCS Runoff Peak discharge = 5.910 cfs Storm frequency = 10 yrs Time to peak = 718 min Time interval = 1 min Hyd. volume = 12,100 cuft Drainage area = 1.050 ac Curve number = 78.9 Basin Slope = 0.0% Hydraulic length = 0 ft Tc method = User Time of conc. (Tc) = 5.00 min Total precip. = 5.33 in Distribution = Type II Storm duration = 24 hrs Shape factor = 484 Post Development Area #2 Q (cfs) Hyd. No. 4 -- 10 Year Q (cfs) 6.00 5.00 4.00 3.00 2.00 1.00 000 6.00 5.00 4.00 3.00 2.00 1.00 0 00 0 120 240 360 480 600 720 840 960 1080 1200 1320 1440 — Hyd No. 4 Time (min) 21 Hydrograph Report Hydraflow Hydrographs Extension for AutoCAD® Civil 3D@2016 by Autodesk, Inc. v10.5 Friday, 05 / 5 / 2017 Hyd. No. 5 Post Development Area #3 Hydrograph type = SCS Runoff Peak discharge = 4.267 cfs Storm frequency = 10 yrs Time to peak = 718 min Time interval = 1 min Hyd. volume = 8,689 cuft Drainage area = 0.790 ac Curve number = 77.4 Basin Slope = 0.0% Hydraulic length = 0 ft Tc method = User Time of conc. (Tc) = 6.60 min Total precip. = 5.33 in Distribution = Type II Storm duration = 24 hrs Shape factor = 484 Q (Cfs) 5.00 M 3.00 2.00 1.00 0.00 0 120 240 Hyd No. 5 Post Development Area #3 Hyd. No. 5 -- 10 Year 360 480 600 720 Q (Cfs) 5.00 4.00 3.00 2.00 1.00 0.00 840 960 1080 1200 1320 1440 Time (min) Hydrograph Report Hydraflow Hydrographs Extension for AutoCAlDO Civil 3D® 2016 by Autodesk, Inc. 00.5 Hyd. No. 6 Post Development Bypass #4 Hydrograph type = SCS Runoff Peak discharge Storm frequency = 10 yrs Time to peak Time interval = 1 min Hyd. volume Drainage area = 1.080 ac Curve number Basin Slope = 0.0% Hydraulic length Tc method = User Time of conc. (Tc) Total precip. = 5.33 in Distribution Storm duration = 24 hrs Shape factor Post Development Bypass #4 Q (cfs) Hyd. No. 6 -- 10 Year 4.00 3.00 2.00 1.00 22 Friday, 05 / 5 / 2017 = 3.823 cfs = 719 min = 8,064 cult = 67.9 = Oft = 8.10 min = Type II = 484 Q (cfs) 4.00 3.00 2.00 1.00 M1r O 0 120 240 360 480 600 720 840 960 1080 1200 1320 1440 1560 Hyd No. 6 Time (min) Hydrograph Report 23 Hydraflow Hydrographs Extension for AutoCADO Civil 3D@2016 by Autodesk, Inc. v10.5 Friday, 05 5 2017 Hyd. No. 7 Post Development Bypass Area #5 Hydrograph type = SCS Runoff Peak discharge = 3.057 cfs Storm frequency = 10 yrs Time to peak = 718 min Time interval = 1 min Hyd. volume = 6,479 cuft Drainage area = 0.660 ac Curve number = 75.6 Basin Slope = 0.0% Hydraulic length = 0 ft Tc method = User Time of conc. (Tc) = 7.30 min Total precip. = 5.33 in Distribution = Type 11 Storm duration = 24 hirs Shape factor = 484 Q (Cfs) Post Development Bypass Area #5 Q (Cfs) Hyd. No. 7 10 Year 4.00 - 4.00 3.00 - 3.00 2.00 - 2.00 1.00 1.00 0.00 - 0.00 0 120 240 360 480 600 720 840 960 1080 1200 1320 1440 1560 — Hyd No. 7 Time (min) Hydrograph Report 24 Hydraflow Hydrographs Extension for AutoCAD® Civil 3D® 2016 by Autodesk, Inc. v10.5 Friday, 05 15 / 2017 Hyd. No. 8 BMP Wetpond #100 Hydrograph type = Reservoir Peak discharge = 0.658 cfs Storm frequency = 10 yrs Time to peak = 744 min Time interval = 1 min Hyd. volume = 11,207 cuft Inflow hyd. No. = 3 - Post Development Area #Max. Elevation = 867.32 ft Reservoir name = BMP Wetpond #100 Max. Storage = 6,870 cuft Storage Indication method used. BMP Wetpond #100 Q (cfs) Hyd. No. 8 -- 10 Year Q (cfs) 7.00 7.00 6.00 6.00 5.00 5.00 4.00 �_- --- — 4.00 3.00 3.00 2.00 2.00 1.00 1.00 0.00 - 0.00 0 300 600 900 1200 1500 1800 2100 2400 2700 3000 — Hyd No. 8 — Hyd No. 3 Total storage used = 6,870 cuft Time (min) Hydrograph Report 25 Hydraflow Hydrographs Extension for AutoCAD® Civil 3D@2016 by Autodesk, Inc. 00.5 Friday, 05 / 5 / 2017 Hyd. No. 9 BMP Sand Filter #200 Hydrograph type = Reservoir Peak discharge = 4.800 cfs Storm frequency = 10 yrs Time to peak = 720 min Time interval = 1 min Hyd. volume = 10,264 cuft Inflow hyd. No. = 4 - Post Development Area #2/lax. Elevation = 852.55 ft Reservoir name = Sand Filter #200 Max. Storage = 3,844 cuft Storage Indication method used. BMP Sand Filter #200 Q (Cfs) Hyd. No. 9 10 Year Q (Cfs) 6.00 - 6.00 5.00 - 5.00 4.00 - 4.00 3.00 - 3.00 2.00 - 2.00 1.00 1.00 0.00 0.00 0 180 360 540 720 900 1080 1260 1440 1620 Time (min) Hyd No. 9 Hyd No. 4 Total storage used = 3,844 CA Storage Indication method used. Q (cfs) 5.00 m 3.00 2.00 1.00 BMP Sand Filter #300 Hyd. No. 10 -- 10 Year 0.00 ' ' 0 180 360 540 720 900 1080 1260 1440 Hyd No. 10 — Hyd No. 5 ® Total storage used = 3,524 cuft Q (cfs) 5.00 [gIQ11] 3.00 2.00 1.00 WWI- 0.00 1620 Time (min) 26 Hydrograph Report Hydraflow Hydrographs Extension for AutoCAD® Civil 3D@2016 by Autodesk, Inc. 00.5 Friday, 05 / 5 / 2017 Hyd. No. 10 BMP Sand Filter #300 Hydrograph type = Reservoir Peak discharge = 2.536 cfs Storm frequency = 10 yrs Time to peak = 722 min Time interval = 1 min Hyd. volume = 7,360 cuft Inflow hyd. No. = 5 - Post Development Area #Blax. Elevation = 865.32 ft Reservoir name = Sand Filter #300 Max. Storage = 3,524 cuft Storage Indication method used. Q (cfs) 5.00 m 3.00 2.00 1.00 BMP Sand Filter #300 Hyd. No. 10 -- 10 Year 0.00 ' ' 0 180 360 540 720 900 1080 1260 1440 Hyd No. 10 — Hyd No. 5 ® Total storage used = 3,524 cuft Q (cfs) 5.00 [gIQ11] 3.00 2.00 1.00 WWI- 0.00 1620 Time (min) Hydrograph Report 27 Hydraflow Hydrographs Extension for AutoCAD® Civil 31302016 by Autodesk, Inc. v10.5 Friday, 05 / 5 / 2017 Hyd. No. 11 Post Development Area #1 Hydrograph type = Combine Peak discharge = 13.34 cfs Storm frequency = 10 yrs Time to peak = 720 min Time interval = 1 min Hyd. volume = 32,167 cuft Inflow hyds. = 6, 7, 9, 10 Contrib. drain. area = 1.740 ac Q (Cfs) 14.00 WIIII11 10.00 M RM fflo 2.00 Post Development Area #1 Hyd. No. 11 -- 10 Year Q (Cfs) 14.00 12.00 10.00 we M-1 M 2.00 0.00 1 1 10.00 0 120 240 360 480 600 720 840 960 1080 1200 1320 1440 1560 — Hyd No. 11 —Hyd No. 6 —Hyd No. 7 —Hyd No. 9 Time (min) — Hyd No. 10