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HomeMy WebLinkAboutDrainage Reports - 08/22/2014Final Drainage Report For Hickory Commons Fort Collins, Colorado Prepared for: Hickory'Commons, LLC c/o Charles Meserlian 1222 Trapper's Point Drive Fort Collins, Colorado Prepared by: ENGINEERING 908 Laporte Avenue Fort Collins, CO 80521 (970) 219-2834 June 28, 2014 Final Drainage Report For Hickory Commons Fort Collins, Colorado Prepared for: Hickory Commons, LLC c/o Charles Meserlian 1222 Trapper's Point Drive Fort Collins, Colorado Prepared by: ENGINEERING 908 Laporte Avenue Fort Collins, CO 80521 (970) 219-2834 June 28, 2014 ENGINEER'S CERTIFICATION 1 hereby state that this Drainage and Erosion Control report for the Hickory Commons subdivision was prepared by me or under my direct supervision for the owners thereof and meets or exceeds the criteria in the City of Fort Collins Storm Drainage Design Criteria and Construction Standards. Stacy j. Gowing Registered Professional Engineer State of Colorado No: 34290 TABLE OF CONTENTS I. INTRODUCTION ............................................................................................... II. GENERAL LOCATION AND DESCRIPTION ............................................... 1 AProperty Location.......................................................................................................................... B. Description of Property................................................................................................................I III. DRAINAGE BASINS AND SUB-BASINS......................................................... 2 AMajor Basin Description...............................................................................................................2 B. Existing Conditions........................................................................................................................2 C. Developed Conditions..................................................................................................................2 IV. DRAINAGE DESIGN CRITERIA......................................................................3 ADevelopment Regulations............................................................................................................3 B. Development Criteria Reference and Constraints................................................................3 C. Hydrological and Hydraulic Criteria.........................................................................................3 V. DRAINAGE FACILITY DESIGN....................................................................... 3 AGeneral Concept............................................................................................................................3 B. Specific Details — Detention.........................................................................................................4 C. Specific Details — Stormwater Quality......................................................................................5 D. Specific Details — Swales..............................................................................................................5 E. Specific Details — Inlets and Storm Sewer................................................................................5 F. Specific Details — Curb Cuts........................................................................................................6 VI. SEDIMENT/EROSION CONTROL................................................................... 6 VII. CONCLUSIONS..................................................................................................6 A Compliance with standards.........................................................................................................6 B. Drainage Concept..........................................................................................................................6 VIII.REFERENCES ...................................................................................................... 7 IX. APENDICES.......................................................................................................... 7 INTRODUCTION This report presents the pertinent data, methods, assumptions, and references used in analyzing and preparing the final drainage, erosion control and water quality design for the Hickory Commons subdivision project (the "project"). GENERAL LOCATION AND DESCRIPTION A. Property Location The project is located on the north side of Hickory Street. The legal description is: A tract of land located in the Southeast One -quarter of Section 2, Township 7 North, Range 69 West of the Sixth Principal Meridian being all of Lots I through 8, Block 21, of the Riverside Park Subdivision, a subdivision of record in the City of Fort Collins, except the West 5 feet thereof and together with the West Half of the vacated portion of Fourth Avenue; and all of Lots 9 through 18, Block 21, of the said Riverside Park Subdivision, together with the East Half of the vacated Alley and that part of the West Half of the vacated portion of Fourth Avenue in Block 21 of the said Riverside Park Subdivision, County of Larimer, State of Colorado. p_ . z: 213 . ZH7 Vicinity Map, NTS B. Description of Property I. The project site is currently undeveloped. The proposed use is multi -use live/work project consisting of 26 two-story units in 7 separate buildings. The project also includes widening of Hickory Street, utilities and site improvements such as garages, parking areas, drive aisles, hardscape and landscaping. III. DRAINAGE BASINS AND SUB -BASINS A. Major Basin Description 1. The project site lies within the City of Fort Collins Cache La Poudre River Basin. 2. The project site is located outside the I00-year and 500-year floodplains, as shown in the following image from the City of Fort Collins webs�i+te: f B. Existing Conditions The project site is currently undeveloped. The site is currently covered with native and volunteer vegetation, and slopes gently from north to south at approximately 1 %. C. Developed Conditions The site will drain from north to south through a series of storm sewers and overland flow paths. The majority of the developed flows will ultimate drain through a detention/water quality pond to a proposed storm outfall pipe along Hemlock Street towards the west. A small portion of the flows on the west, east, and south edges of the site will run off the site un-detained. These flows are significantly less than the existing flows leaving the site. 2. The off -site storm outfall pipe will be a public line, serving adjacent properties with the conditions discussed herein, in addition to the Hickory Commons site. 2 IV. DRAINAGE DESIGN CRITERIA A. Development Regulations I. Design criteria from the City of Fort Collins Storm Drainage Design Criteria and Construction Standards were followed for this drainage report B. Development Criteria Reference and Constraints I. The proposed storm water release rate is 4.71 CFS, which is the capacity of an 18" RCP pipe at 0.2%. The outfall pipe is proposed as a 21" RCP, which has capacity for 7.11 CFS. The remaining capacity of 2.4 CFS is allocated to adjacent properties as shown on the enclosed Drainage Exhibit and Grading Plan. C. Hydrological and Hydraulic Criteria I. Hydrologic and hydraulic criteria is as per the City of Fort Collins Storm Drainage and Design Criteria and Construction Standards. 2. Analyses are performed using City of Fort Collins spreadsheets and the methodologies presented in Urban Storm Drainage Criteria Manual Volumes I and 2; Urban Drainage and Flood Control District, Denver, Colorado, September, 1999. 3. Please see the various computation spreadsheets in Appendix I. V. DRAINAGE FACILITY DESIGN A. General Concept I. The general direction of proposed storm water flow is from north to south. 2. Storm water from the improved section along Hickory Street and the majority of the site flow though a series of storm sewers to a proposed detention pond located at the southwest corner of the site. Additional detention is provided within the drive aisle. The detention pond discharges to a proposed off -site storm outfall pipe located within the ROW for Hemlock Street. This pipe ultimately discharges to a natural drainage way near the entrance to the McMurry Natural Area. 3. Although the off -site storm sewer is entirely located within the right-of-way for Hemlock Street, an easement has been obtained from the City of Fort Collins Natural Areas to accept the drainage discharge for conveyance to the river. 3 B. Specific Details —Detention The treatment drainage area for the site is 2.09 acres, which includes the project site and a portion of the Hickory Street ROW located along the frontage of the site. Only 1.89 acres on the project site is able to drain to the detention pond, however 2.09 acres is the calculated area that will be treated for detention by the new detention pond. a. The release rate for the project is proposed to be 4.71 CFS, which is the capacity of an 18" RCP at 0.2% slope. It should be noted that additional capacity is provided in the proposed 2 1 " RCP outfall storm pipe to allow for adjacent properties to drain to this public storm drain pipe as discussed above. In general, those properties are located along the north side of Hemlock Street, west of the project site. b. The drainage basin is 90% impervious, which requires 0.084 acre-feet of extended detention volume. The water quality volume is provided at elevation 4973.19'. The calculations for the water quality volume are located in the appendix. c. The required detention volume was calculated using the City's rational formula based detention pond design worksheet. The required detention volume is 0.196 acre-feet. The total required volume of 0.280 acre-feet is provided at elevation 4974.70'. The calculations for the detention volume are located in the appendix. d. A relatively small amount of detention volume is provided in the drive aisle. The maximum depth of the 100-year ponding in the drive aisle is 1.1'. e. There are 0.20 acres of the site on the west, south, and east borders that will is not able to drain to the detention pond and will instead runoff the site undetained and untreated. These flows are generated by Basin B and C and total 0.93 CFS for the 100-year storm and 0.18 CFS for the 2-year storm. This is less than the existing 100-year runoff from the site, which is 2.79 CFS, but more than the existing 2-year runoff from the site which is only 0.06 CFS. 2. As previously mentioned, the detention pond drains to a proposed public off -site storm outfall pipe located within the ROW for Hemlock Street, ultimately discharging to the Cache La Poudre River. 3. An emergency spillway path is provided for the undetained 100-year flow from the site (20.8 CFS) plus the developed, detained flow from basin OS I (0.22 CFS), located within the southern drive aisle for the site. The spill elevation for this structure is 4974.88'. The depth required to convey the developed un-detained 100-year discharge from the site is 0.42'. u C. Specific Details - Stormwater Quality Water quality is provided in accordance with Best Management Practices as presented in the Urban Storm Drainage Criteria Manual Volume 3. Best Management Practices; Urban Drainage and Flood Control District, Denver, Colorado, September, 1999. 2. Permanent structural BMP's consists of extended detention within the proposed detention pond. See the above discussion of the detention pond for more details. D. Specific Details - Swales There is an 8' wide swale with 5:1 side slopes to the east of the property boundary on City of Fort Collins Parks property. This swale is designed to convey 133% of the 100-year storm for Basin B at a depth of 0.39'. This 8' wide swale and landscaping adjacent to the 10' wide concrete trail will be maintained by the developer as per an agreement between the two parties. E. Specific Details - Inlets and Storm Sewer I. Runoff discharges from Hickory Street are collected in a proposed Type R inlet located in a sump condition. The drainage area to this inlet is quite small, and a 5' Type R inlet is more than adequate to collect the developed 100-year runoff discharge. 2. The majority of the discharges from the site are collected by proposed Type 13 inlets in the inverted -crown drive aisle. These flows are conveyed along with the flows from Hickory Street through a series of storm sewers to the detention pond. 3. The minor flows on the western side of the site will be collected in a swale within the sidewalk and conveyed to the detention pond. 4. 100-year flows are conveyed through the site with a combination of storm sewers and the swale created by the inverted crown of the drive aisle. Storm sewer calculations are included in the appendix. S. A plugged storm sewer stub is provided to the property immediately to the west of the site (Basin OS I) for future detained discharges. This pipe and downstream pipes within the site are sized based on an assumption that this site will be developed using a standard release rate of 0.2 CFS/acre (0.22 CFS). It is important to note that the proposed drainage systems within the site cannot accept discharges in excess of this amount. 5 r� u 6. An off -site storm sewer is proposed to convey discharges from the site to the Poudre River. This 2 1 " RCP has a capacity of 7.11 CFS. As previously discussed, the release rate for the project site has been established as 4.71 CFS and the discharge from the adjacent property 0.22 CFS. Since the release rate for future developments contributing to this storm sewer is 0.20 CFS/acre, the excess capacity of 2.18 CFS will accommodate 10.9 acres of additional development from adjacent properties. F. Specific Details — Curb Cuts I. There are no curb cuts proposed with the project. VI. SEDIMENT/EROSION CONTROL Temporary erosion control measures will be installed with this project, as detailed under a separate report entitled "Erosion and Sediment Control Report", dated 7/27/2014, prepared by Apex Engineering. VI1. CONCLUSIONS A. Compliance with standards I. All drainage design conforms to the criteria and requirements of City of Fort Collins Storm Drainage Design Criteria and Construction Standards. 2. Proposed drainage improvements conform to the concepts and recommendations of the Dry Creek Basin master plan. B. Drainage Concept The proposed drainage plan concept for control of stormwater runoff and water conforms to City of Fort Collins standards. the project will be effective for the quality for the proposed site and 6 VI11. REFERENCES I. City of Fort Collins Storm Drainage and Design Criteria and Construction Standards 2. The Dry Creek Basin Master Plan 3. Urban Storm Drainage Criteria Manual Volume I; Urban Drainage and Flood Control District, Denver, Colorado, March, 1969. 4. Urban Storm Drainage Criteria Manual Volume 2; Urban Drainage and Flood Control District, Denver, Colorado, March, 1969. 5. Urban Storm Drainage Criteria Manual Volume 3. Best Management Practices; Urban Drainage and Flood Control District, Denver, Colorado, September, 1999. IX. APENDICES Appendix I - Hydrologic Calculations ■ Peak Discharge Calculations Appendix II - Hydraulic and Detention Calculations ■ Detention Pond Sizing Worksheet ■ Water Quality Calculations ■ Pond Stage -Storage Worksheet ■ Storm Sewer Calculations ■ Emergency Spillway and Swale Sizing Reports Appendix III - Mapping and Plans ■ Drainage Exhibit (24"x36") 7 C Appendix I — Hydrology CALCULATION OF A PEAK RUNOFF USING RATIONAL METHOD Project Title HICKORY COMMON S Catchment ID. basin Al. 100-yea Discharge for Storm ADesign I Catchment Hydrologic Data Catchment I D = Al Area= 1.22 Acres Peroertt ItrParviasness = 90.00 % NRCS Soil Type = B A B. C. or D ` - Y Rainfall Information I linch?rr) = C1 ' P1 ((C2 + Td)" C3 CDesign Storm Retum Period. Tr = 100 y es> I input rerun period for design storm) C1= M50 l input the value of C 1) Cat= 10 00 (input the value of Cif Cat= 0 793 (ir+put the value of C3) P1= Z 51 indves [input onia-M praripti tion-see Sheet ''Cesign Ir•a:• i t 10. Analysis of Flow T'mro (Time of Concentration) for a Catchment Runoff Coefidrx. C = 0.81 Overi oe Rurci CoefidMt C= lerta a^ overlde C value if mifec, or leave dlarx to accept caoulatec C 5-yT ?:.noffCaeffioient C-5= 0.73 CWYIce f-yr Rl neff Ceeticient. C = enter an Cverice C-F v3ILe 0 oes fed. or IEwe 7l>9na to a calculeleo C-� Illustration N l /��' w'rful LEA l 1 Our Read S f el 50000 Flwr DUmdn Nr-r► i B.a4� A -.-_--_ _ '',3ge,' sa- ve31�. Grassea Paved Areas& ?.,Cc -?L C.ew `?_-y,'=_ Safe S0r3im Sh.3-ice. F3.e-S.c3:e=_ Cala,letrons f,eQI01-31 I C = 11 Lo PeakRtmoff Predidi in using Cornputed To diction using Regional To RairbilIntensity atTc,1= 8.83irx—. °.a -fall Inter5ay at To,1= 724inch hr Peat Fiewae. Cc= 8.72 cfs Pea. Flux^ate QP= 71C• cfs 1.9 CALCULATION OF A PEAK RUNOFF USING RATIONAL t9ETHOD Project Title: HICKORY COMON S Catchment ID: Basin A, 100-year Discharge for StormA Design 1. Catchment Hydrologic Data Cat&i ei,tID=At Area= 1.49 Has Percent ImpervtoLaness = 9300 % NRCS Scil Type = 8 A B. C, cf C F. Rainfall Information 1 linchlhr) = C1' P1 f(C2 • TdM3 Cesigr Serra Relurr Period, Tr = 100 years I inpu return percd for Cesigr star rri� C 1 = 2850 1 input the value d C 1) C2= 10.00 ( input the value of C2) C3= 0 793 (input the value d C 3) PI= Z91 in m (input arahr pecipitaliar.-see Sheet'Cesigr Inb') 11. Ark*sis of Fbw Time (Time of Conoentratkm) fo► a Catdnment Runoff CoeNiclent, C= 095 Overide Runoff Coefficient C= lenter On DVe ide C value if desiredor leave dared tD accept calculated C ; 5-yr. Runoff Coefficient C-5= 0" Cverde fryr Runoff Coefficient. C = lent i an overide C-ff value if desiret. D, leave tlar. in accept caladaied C-`_ ) Illustration N Krrrk r A {� IGarAi Oow Resr IN Flow Diswdei c.ekr l u.0 ."ry 5RCSL3-c idlapre S'tpt ri[ael titmse: F'w.� d.�re3s& T y[� I.te3d,o� =�e'y Fs=_e:re c3•e S..ax S . - - f _ S:rales „or eys ralculatldns Reash S�o =- Ler tt f-�r %p CS C S L Rmff Convey, 4ec_-, Tdre Cod ante Tf Rft t CT - input input output input output output Overland 3 54 1 0. 359 00 Computed 141 4.3t 2 Warn425 Tc = 789 Kagiona to= 1t l Peak Runoff Prediction using Computed Tc diction using Regional Tc R airfae l Wrens ity at Tc, 1= 8.42 inch hf Randall lrtensity at Tc, 1= 7.05 mJ,. fit Peas Fbn+ate. Qp- 1o.55 Lfs Peat: Flomate, Qp- 8 93 cis 7 CALCULATION OF A PEAK RUNOFF USING RATIONAL METHOD Protect Ttle. HICKORY COrM)OtlS Catchment ID'. Emstng 2-year Discharge from Ste 1. Catchment Hydrologic Data a"s"rrw+tlC= Bert Ares = 209 Aa es Psoent imperviousness= 200 % NRCS Sod Type= a A S. C, ^ 0 1. Rainfall Information 1 (inc hbr) - C1 • P1 I(C2 s Td)^C3 - amigr S9rm. RslIum Period, Tr = 2 ymts Input retum period for design Storm; C1= 2850 (Input the va6rrdC1) Cr 10.00 tinpttthe value ofC2,1 C3= 13.79t3 Irphtthe value ofC31 P1= 0,82 imt es I input one -In precipitation -see Sneet 'Desi®r Irt It. Analysis of Flow Time (Time of Concentration) for a Catchment Runot Coeffroett. C= 3 33- Overioe Runot Coeffdert C= :enter an ovende C value if lesseea leave tiane m accept ralculatee C 5-yT. RLM11 Coefficiert C-5= 0.08 Ovenide `-yr. Ru•wt CoeffiaM. C - lenrta an overide C-5 value d oersted. oT leave blanr. m accect ralcutsLc C-O N Illustration -� wrxLwt Rrmh 1 dw RrmIs2 -r _) Rrdndwc Flow Dimdmi r-- 6blurwr RCS 13rd Ks.y -'3c- :�-^. 'ver; Griae� Fared,r-as& Type : ea Ind FEi7 3x"- c __ c SA'alas Sr3.':•. "a.Er S�3*s -3:lrs - L'i 3:e:':35 Steet%0. meysrx C alct.latic rs Reach Sboe -engtt I.z I - Fl,+: Ft✓�; D S L c.rc= _ - -. ec,-n Tine CW a oc Tf 1rt It C-5 fps n1nues meet "put cuput input ytpur output Overland 0.0100 0 38 0m 40 1 0 F Con-ps.ted Tc = 4070 'egjcral Ic= i<,rt Peak Runoff Prediction using Comptrtesd Te itbon using RegionalTc e aria:: ;ry a: Te l = IAT inch" Rainfall IrtersiD, of Tc, l = 201 I,k. nr cam• cic.v'•3tE = DOC cis Fc cl-"t-a[c.'Oc= 0.1-- d; W CALCULATION OF A PEAK RUNOFF USING RATIONAL METHOD Project Title HICKORY COsh1AOH S Catchment ID: Existing 10"ear Dischargefrom Site I. Catchment Hydrologic Data CatlTmer!ID= But Araq = 209 Acres Parser[ IrrpervhihSnss = 200 % 1vPCSSctTym= BAB.C.orD 1. RahnfaIIInformation Ilinch 0hr)=C1•P1/(C2+Td)"C3 Design Sbrrn cat-- �3 ix T- = 100 years I input feturn per ad fir design starrM I rPht the value of C l ) 10.00 I rput the value of C 2 C3= 0793 1 input the value d C 3) P1= 291 rdres I input ore-hr pecipitation-see Sheet 'Design Inbi IN. Analysis of Flow Time (Time of Concentration) for a Catdumert Runoff Coefficiert. C= 0.X OveideR inoff Cieffi dens C= lento a cvEr a e C cal Le oes rec, or leave Garr. r accept ceWallei C.) °-yT P. niff Coefficient C-5- 0.08 G�'erce Syr Purmff Coefficient. C- ;enter a --vgioe C-5 value t des red, or leave blare c aocept calculated C-5 ) Illustration N Wr►:t.I r< Rrvh i J M DlnsWh f Carkhw..r tboip ^S -a-c -ra.•, T peat; =ratse= eve eas & Type '.'era: _�<:.� :;2.•e 5are 3v:s 3:a11ow Patted &oaks _ ':b aaicr.: �5 $fR4I Ffp0.'r .Ar'R ndeU 11---7 11CJ Calm laticr s Re :h = - - .arch MRCS Raw Fro,.. C = Puroff Convey, Velocity Tir1>f coo Znta V T' _ It C;, fps M%%F "D-t rrput OVIDO Input autprt overianc 0.0100 490 039 0 t 3 4 5 Sum 430 -Iomct sec Tc = 40.70 Hegioral Tc= 12.Ti Peak Runoff Prediction. using Computed Tc dicion using Regional Tc 31r6II -!e ;rt; 3t Tc. 1 = 2 eS I-d-.. -• '.31^(jll at L I = e 97 r::r. ^( Fr5•'Wc= z —d Gs Fe3.-1c.,'31e.CL= `u cis F CALCULATION OF A PEAK RUNOFF USING RATIONAL METHOD Project Title: HICKORY COM LAC r15 CaehrnentID. Basin8.2-aearDscharoefor CtfsrteCesim L Catchment Hydrologic Data C.33Dhr.er,tI-_= B Area= 0.11 ACRs Percm Intpermusmss = 75:DD'. MRCS Sal Type = B A. B. C. orD 11 Raffailkformatim 1(kwWhj=C1'P1(C2+T4"C2 :t •- Wit- �O-W. Tr = 2 mrs fmolt return nerc•1. `7r :.es,:- st "-. C C1=-3815if fttl the Mue v, C?- fmpd the slue 7 C=. C3.—'m u the A--,e d C3,. .. Ptie<i�11nb'; It Arelyss of F1w Tine (Tkm of Cmm,ih tioN for a Cachnere Coeficlert C = 0.51 3E =_--4, 3mCf lwt C= IertS 3r pnerr:F C '4ue A:ES'eC. Jr lea'+e Dlar�Y.toaroect ratLHE4 C =_c=:CefioatG5= 0.54 ie rter an cr*rm G. 's IIE i` CS ireJ. or IE9',e pi3rk b 3Joept c9cLsaw C 5. j Muskation C fV Dow GLG[?¢ s. M+-o _. .5-. -:.. 2x 5^04 -3'.e`ArE35A caiO'R� ?a= Sa 3kE 5^3 V:r=3: e. S.t3CIE Laws cr:.`" 0.3P_ra3.'- 5^eet'c., '-.s--zt-r' Peg" Te= 12V PeakRurdfPredictionusingComputedTc edctimusingRegionlai Tc -a..a..-terst; a:T:, I= r--n -'a'-ters.tva Tc, 1= 2.02 MCK tr `ea, %:Tae. Cpw r9tri;nrafe, Qp ITTt ff 4-ckwyCortrors - LC P,atora Eas,r E :f STOPJ.'. E )Es. T: arc =-*- 10+242D72.109B AM 12 CALCULATION OF APE AK RUNOFF USING RATIONAL LIE THOD Project Tale FlICKORY COM IAONS Catchy erit lO Basing, I00-year Discharnefor %Yale B andOffsrte Deslm 1. Cathmert Fydrolow Casa Camtrr'atID= B Area= 0.11 Aces =�rrnIrwJvu5ness= '•: N R.CS Sol Tyne =- 9A. B, C. orD 1. Ravial Homriion 1Imwlv1h =C1 • P14C2 • Tc*"C wood. Tr = 10D was 6rpu raur terDz. b Jes#:;r sorrr: Ct =-1i= firpu the ' W t Q 4 C< 19.w0 (rnpu the slue { CZ m=--- 'Sm fir -pa tresue,,i:T, P7=.1 Inrhas irnpu St -Mt DK,7 Irt-, It Analysis of F1wrTine (Tine of Concertrahonj for a Catchment a. StC- �Dr Jre'><F_•_`:-:ti_,r,C-e-tzar:,rr,3kCaloe0-es,rec.:rleawbJanktoammaptmtuC@yC.! e-y Rum! Coa'Faart C-:• = D!4 O•atrde`-y Rur+oA!Coe9ieiantC= ert>a• _+er�3e: `.s.* `xsIrr..riea•redark wameptt:ak:JaladC-5.t nl�rtrarw, rr tCrr G:� � 9R�w1C Fbw Dtwr,kr - r'e3=ca 'k!k] =3e:.k �39_ 5:. e•- - . =�.{' ° PneralTc= 1,2'.7 Peak Runoff PmiJi tionusmgCtmµtedTc eddtmusing FitWnal Tc rtersr.,vTc: _ "*. nChM Paj-�:;C l rteryrxTa I= `r 4ciaryComar ors - UO Ratonal Basin B IMV STORU Bads. T c r. ?aae' 1 y14D12.1D:38 AM 13 CALCULATION OF APE AK RUNOFF USING RATIONAL NJETHOD Project Title: HICKORY COMMONS Catchmertl6 B3sinC.2-vex Discharge to Ado-:ableOffsteRms I. Cathmert Hydrologic Data c4ml rertlD= C Area= OD9 Acres =erm-rt Imper towwSs=Do '. MRCS Sal Type= 6 A., E. C. or l Rainfall ktomubm I ticlvlO =Ct • P7 AC2+ Tcj'M Design Siorm Peum Pww, Tr = 2 ,.ems Iinpa r4turr perDd is desCr, sc ,-- C.,=� fmgttte Md eofCn C2:; Idw 6npuC tta •slue of CZ C'. D lmputtte '+Auecdcl P1= .82 en&415 (mote orp-nr t2upU a�w Shwt 2k— :r, Ir t ; IlArrifyssafFkmTimm (TimeofC wetratioNfaraCAch-pvt %rbfTCeftrrartC- om O+er).E'R.unpf'fCDeftlertC= lemaano.endeC•alued*stw rle3'.eb6nktpamept'MCLA*e C.i 5-V. Runof Omfiicwt G5 = 0.35 Overde:-yFhavPCoeEi-antC= ertean�eriSeGS'aleraaia.cr'�ebait3cceptaicJateCC-5.; pl �xtr3firr: lu 3" b 1 81s. IYsr h r _7 Mr LwL u Iwo Dtayr C.,Ju..aa B....Lq r D.: C wA np rl oa:N, ow=i 3 v;a t ' 5-: 2J 0.35 ]:?3 3. T z SuT Convaw%z 3.55 magona I c= ?V.l- Peak RurdfPredictionusirgCanpAedTc eddionusing PbowW Tc Fbrftl lnMstvatT c l= 3.01 rchtr Aantil lrtetsity3Tc, 1= 221 lndi,fT Peak Fburae Op =-3 78 ct Peak Flowraw Oa =— UM crs liokwyCcrtmpne - UDRaona Basin C 2y STORM CA-, Te atd F eakC a 02a'Ir312.10:33AM 14 CALCULATION OF A PEAK RUNOFF USING RATIONAL METH OD Project Titie: HICKORY COMMONS CActmert IU 8asn C. •Wf-rear Discharge forAllavabde Off site Flov6 I. Cathmert Hydrologc Data Cavrre-tlC= C :re3= C:D9 Acres Peruert 50:X" N PCS frail T5ce= $A, S. C. or t Rairf3l Irtormatim I (indlrh„ = Cl ^ Pt $C2+ Tdj'C3 Doren Stm Relum Penod, Tr = 133 \ears rmou rieurn cerod trdesm st •r- C' = -✓r'S Iinpd the ,due of C1) Cr- ITY5 rani t the ,sue ci CZ C r-. 0.793 (rnPLa the *Mu* Of C31 P'- i.Fl indg C6iTIrt) It A raysis of Rwv T int (Time of Conamtratianj for a Catelmert Runoff C,*fi::Jwt C = C 52 O`erltp Punetf Coef wt C = !emer an o*D* C `atue fidegred, a *z a blank malt aCulared C ; :y Rurof Ccefawt :,5 _ 0.35 Ore 5-5c Runof Coegrmrt C = iertet an o mM C-5 Wm -f Issued, or km* dark ID acoept calcdai= C-5. .�SIiC.d90[I IV c�3rv:a1 9s� � `� Poor Dtasyn! 71 _Ia>t MN N31e6 59117Seei 5 :3leraa.s 91 i,r IY. cs -b* I -C.. Fx V .-, - .. C-5 r%i o.mJ. I" ns aao.r -r.-. e: PE;C3 - ] _ - - Peak Rurm f Predctionusing CanpAL-dTc edrQionusing RegorW Tc P3m€� rrerstyatTc 1 = V).49 rc tv Pa,•!al! Ina•Srtya Tc l = '38 mth••tr ftimryCa mars - L C•Rator* Emr C *DV STORM Cads. T c am7 Peak,.^ 1024D12.10 S3AM V Appendix II - Hydraulics Detention Pond Sizing Worksheet Hickory Commons .C.. vdue 'C' 125 Area 209 acre: Rekase Rate 1 4.71 DETENTION POND SIZING ThJs is to convert % imp to a C value Pegmred detentes imust�mert%x p. andC pernousl G- I 4, Modrfied ModAed M EATER D fUDISH C LI 51% Nov-97 Nov-96 PME I nv TIME aimm. isecs� INTENSITY 30 rear un4,1 Q 100 Ids1 Runoff Volume ife31 Release Cumin. total Ie3j Regwred Detention (ft"3) Required Detenbon uc-ft, 0 0 000 0 DO 0.0 O.DDOD 300 9950 2080 6238.65 14130 48257 01108 6D0 7.720 1613 %80.88 28260 68549 0.1574 5 900 6-S20 1363 1226412 42390 SIMI 0.1842 2D 12DD 5.600 11-70 140443 5652.0 83928 0.197r 25 1SDO 4.900 1041 156123 706So 85473 01962 30 18Do 4.520 9.45 170D424 847110 85262 0.1957 35 21DO 4.OBD a53 17907.12 9891.0 80161 0.1840 4D 24DO 3740 7.82 18759.84 11304.0 745iB 0.1712 45 xw 3.460 T23 1952478 12717.D 6807.8 0.1563 50 30DO 3-230 675 202521 14130.1) 612Z1 0.1405 55 33DO 3030 633 2089791 15543.0 53549 0.1229 60 36DO 2-860 598 2151 a 64 16956.0 45626 0 1041 65 39DD 2720 568 2217D72 18369.0 38D1.7 0.0673 -D ADO 2590 S41 2273502 19782-0 2953.0 0.0678 75 45DO 2-480 518 233244 21195.0 2129.4 0.0489 90 48DO 2380 497 2387616 22608.0 12632 00291 95 51DD 2290 479 2440911 24021.0 38a I O.OD89 90 S4DD 2-210 462 2494206 25434.0 -491.9 -0.0113 95 57DO 2130 445 253,469 26847.0 -14723 -00338 00 60DO 2D60 431 256324 28260.0 -2427.6 -00557 105 63DO 200D 418 26334 29673.0 -3339.0 -00767 A 66DO 1940 405 2676036 31096.0 -4325.6 -00993 69DO I %D 3.95 2725569 324990 -S2433 C 204 - D0 1.840 3.85 2768632 33912-0 -6223.7 429 Apex E ngineen rig ConBdentsal 511M13 Page No Text Pond Stage -Storage Worksheet Hidcory Commons Pond ID: Detention Pond I Input Detention Volume Required = 0.196 acre-ft WQCV Required = 0.084 acre-ft Total Pond Volume Required = 0.280 acre-ft Where: Volume = 1/3(d)(A+B+AB^0.5) d = elevation„ - elevationMI A = area of elevationn.i contour B = area of elevation„ contour Results: 100-year WSEL = 74.70 WQ WSEL = 73.19 Calculations: Cumulative Elev. Area Area Storage Storage (feet) (SF) (acre) (acre-ft) (acre-feet) 70.42 0 0.000 0.000 0.000 71.00 777 0.018 0.003 0.003 72.00 1,522 0.035' 0.026 0.029 73.00 2,505 0.058 0.046 0.075 74.00 4,349 0.100 0.078 0.153 75.00 12,172 0.279 0.182 0.335 1U C il CIRCULAR CONDUIT FLOW (Normal & Critical Depth Computation) Proud: HickoryCormions PipelD: Calculation forAllmatile Release Rate T Mciv eslgn infc; matron ilnputl ice i^:ecccce Sc= 00D::0 fth r.i3--:-,S ^-, 31.- n= 0.0130 ¢e ,.,13^xte D= 18,00 Inches "gn discharge = 4.71 efs „14th.r arm- Af= 4 JIC ,reciec C Er1r —e, Pf = aff �u':'21 -.ngle Treta = ull-now rapaciry Of = 1 _ -C ft ft lacla's ds •. -1 1= 171 i-3N ��ral AnGle <T�eta<'_ 1�, Theta= -Ica aes An= TCc .+1dh Tn= h ettec oe,ir*ve, Pn = F{ca 7ecr Yn= Floc +elcciry Vr - Discharge On= Percent Full Flow Flow= Normal Depth Froude flumber Fr„= ZX radars sgft ft R P. fm ds of full flow suberitical 1.5f. 118 340 1.22 ? 0= 171 100. 00Re 0.i atf �-tral Angle; O�T�*ta-c='_ 14. Treta-C= 'meal flc"area Ar-= r rt,c�t t x .der Tc = ritcal flowdepth Yc= r meal Flcx V OLD Caf Vc= ritical Deptn Freuo*Nurmar I raoia^s s=h R R fm 101 149 0.83 4f7 UW 1 r CIRCULAR CONDUIT FLOW (Normal & Critical Depth Computation) Pro" Hickory Commons Pipe ID Storm Sewer At (Note: 2.2E CF S bypass dovmstreamto pond) �a Y60rtt uir�! . .%iM 1r t1 � Iris: Sly Sc- M1tar, i ;s r._ya1_,E n = =is--.VLer D— gn discharge 0= OMAO f:t inches ofs 0 0130 15.00 6.66 „II-flc'n Bre3 Al = „l-flc%N oerec der irr_[e Ft= atf Cer:rsl Angle Ti ewta = utl-flow capacity Of = 1 - sp ft t ra Mars cts — ? lq 6.66 all er-ral Angle O<Thets<3. 14) Theta = Ic,% Brea Ar = ccaidth Tn= r enee oerimei&r Pn = lo',v oactt Yr = IC,% veiccrty Vn = ischarge On= ardent Full Flow Flow= ornal Depth Froude Number Fr-= ' 25 radials left t f, t fc- CIS of full flow subcritical tE8 11° 3 40 1. Z 430 6-66 100-OOU., 0.65 If Cer::al Able'^,=Treta_n_114; Tneta-c= rtical flca a*ea Ac= Rica) tar mcl!t Tc = iticaf Aowdepth Yc= itical flc.! . elcaty Vc = itical Decx- c,aoe'.:.rite hr_= - !aclars 3-ft ft fps '= 1.00 °_1,-1 1.00 20 CIRCULAR CONDUIT FLOW (Normal & Critical Depth Computation) Propel. HickoryCOrrtf11on8 Pipe ID Smrm Sewer A (0.83 CF S bypass directfy overland to pond) T How 2149 U I^v9: �Icoe f.1ar^i^^ys ^->3f.f gn discharge „ILflca 3S- ., IFFIc �y .ti H:� ca�nl3cr alf C tr91 AryiE ull-Flow opacity So= 000=0 ftf: r = 00130 C = 2100 rcr,s O = 10.05 ds Al Pf = Theta= Of= Zat ;oft ft raotarn ds 5.50 31. 1005 21 Cer:rai=.ngl=_;0<Tha-ta<^' 14, Theta= -:2 rooter; Icn area Ar = Z ' 1 s ❑ ft bG .vrJth Tr = ' M ft '' ct:ec pe'r'rieE• Pr = 2 se It Ic% elect Yr= - -2 ft Ic.% ..4C cry Vr = L -f fie hscharge On= 10.05 ds 'ercent Full Flaw Flow= 100. 00 �z of full flow ormal Depth Froude Number Fr, = 0.i57 subcrtical aIf ::.•:rnlA - ,Mcai flGs 3'E9 r dicW trG a rS". Mica! flowdepth r itical flc.% vdccrty r Rlpl::ecth 6 T huts-c = Ac= Tc = Yc = Vc= rr_= K •a ora •s sift It ft fps - 1.18 °%^ . 00 21 CIRCULAR CONDUIT FLOW (Normal & Cntical Depth Computation) 1 Pro)rct: FiICkOryCOFTrrX)ls PipelD- 21" 0utfall Pipe Aren -e - u Ir o3t Slope So= htwr.mgs r-•:31ue r = Ciemeter C= ;n discharge O = 73000 ft ft incf es ds 0 0130 :10 T11 „IFtlrs 3e3 Al= „14f1r:: ,,erec cgs-W.e• Pf= aM sal =.-gke Theta ull-Flow rapacity Of = 2=1 sph ds �.11 ill Coral A.mle ';: Theta: ° '= Thata = 2T racla-s :.+area An= 211 sgft c %par Tn- 134 ft enec perimeter Pn = 397 ft :A7KT Yn= It iw vekuty Vn = ? 37 fps sdtarge On= 711 ds scent Full Flow Flow= 100.00% of full flow irmai Depth Froude Plumber Fr,= O.d7 subcrtical Iculation of Cntical Flow Condition If =+t-31 ,N* :.=T-e,, �214 Theta-r_= 1.?0 r27U3 mi fl-"ass AC = 1.40 scft d ICal tCC ,fit'' Tc= 174 ft thcal ffowdepth Yc= 0.35 ft Racal flc.v v Nccig Vc = c, 04 fps itiral Depth Ffoude Nurnca hr.- 1 00 22 Hydraulic Analysis Report Project Data Project Title: Hickory Commons Designer: Project Date: Thursday, August 07, 2014 Project Units: U.S. Customary Units Notes: Channel Analysis: Emergency Spillway Notes: Input Parameters Channel Type: Triangular Side Slope 1 (Z1): 25.0000 ft/ft Side Slope 2 (Z2): 25.0000 ft/ft Longitudinal Slope: 0.0200 ft/ft Manning's n: 0.0150 Flow: 21.8200 cfs Result Parameters Depth: 0.4200 ft Area of Flow: 4.4104 ft^2 Wetted Perimeter: 21.0179 ft Hydraulic Radius: 0.2098 ft Average Velocity: 4.9473 ft/s Top Width: 21.0011 ft Froude Number: 1.9025 Critical Depth: 0.5433 ft Critical Velocity: 2.9574 ft/s Critical Slope: 0.0051 ft/ft Critical Top Width: 27.16 ft Calculated Max Shear Stress: 0.5242 Ib/ft^2 Calculated Avg Shear Stress: 0.2619 lb/ft^2 23 11 Channel Analysis: Swale B Notes: Input Parameters Channel Type: Triangular Side Slope 1 (Z1): 5.0000 ft/ft Side Slope 2 (Z2): 5.0000 ft/ft Longitudinal Slope: 0.0050 ft/ft Manning's n: 0.0400 Flow: 0.6800 ds Result Parameters Depth: 0.3937 ft Area of Flow: 0.7750 ft^2 Wetted Perimeter: 4.0150 ft Hydraulic Radius: 0.1930 ft Average Velocity: 0.8774 ft/s Top Width: 3.9371 ft Froude Number: 0.3485 Critical Depth: 0.2583 ft Critical Velocity: 2.0391 ft/s Critical Slope: 0.0474 ft/ft Critical Top Width: 2.58 ft Calculated Max Shear Stress: 0.1228 Ib/ft^2 Calculated Avg Shear Stress: 0.0602 Ib/ft^2 �J Appendix III — Mapping and Plans Fn O n b ffi 0 i 6 � C 6 e S z z g Y 0 � Z 9g W <oA w "' � W s N 0 r $ m � x o � O Q J 0 Z O O u U_ p S SHEET: C8 of C 16