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HomeMy WebLinkAbout2021/05/26 - Watershed Special Permit Application - 325 Johnson Street 1 Vj i , w. PLANNING DEPARTMENT Community& Economic Development Division Specia Permit — Watershed Please type or prinq t clearly. 1. Petitioner: Kevin Alison Sparks . Owners of the Land. Kevin + Alison Sparks Address: 2,15,Johnson et NAoh Aad MA-0L1 8-4 5, Number of years of ownership: 3.Year lot was created: August 25, 1989 (See Phan No. 11603 at Registry) . is the lot currently on septic or sewer' On t ... er ios i to wt to munlicipale t t I °� t If one sewer, please provide date the sewer, n ti was completed: 5. Description of Propoised Project- Construct a detached garage, ex w, gravel driveway, access nevv'_,gqLage,, install 1111111drywell tio captme roof runol newa s crush fill with! sand olds tic to k cess 1 'connect to town sewer, of wettands 6. Description of Premises: Existing angle am 1y hmse, on, 85,480 lot 7 .Address t Property nAffected: 25 us Street, Zoning District: 3 Assessors Map- Lot 7 Registry of Deeds: Book 2986 Page . Existing L wt# Lot Area(Sq. Ft): '851480 Buildingi ; t� Street r wnt e-, 55.2 �1de Setbacks.,- Front Stich Rear Setback: Floor Area Ratio: n Lot Coverage.,, n/a 9. Proposed Lot i I"cable): (Not applicable) Lot,Arera (Sq. Ft)-. Building el t .- ;street Frontage. Side Setbacks Page, 1 of 2 120 Main S t Planning Dept., No,rth, e ,, Massachusetts 01845 Phione 978.688.9535, Fax 978,.688.9542 Web www.nopthand,overma, Front Setback:-,, Rear SetbacR: Floor Area Ratilow. Lot Coverage-, 10. Req uired' Lot(as requ Ired by Zuni n Bylaw): 35 ft Lot Area S . Ft): 25,000 sf Bui'l'd'2ng Heigh . Street Frontage: 125 ft Side Setbacks: 20 ft Front Setback: _30 Rear Setback: 30, ft Floor Area Ratio: n1a Lot Coverage: _n/a 11. Existing Building (if applicable Ground Floor(Sq. Ft.): #of Floors.- A Total S . FL- 22034 Height. Use: S i n q[e FEAT�i I Type of Constr,uction: Wood Frame 12.Proposed Building: (detached' garage), Ground Floor(Sq. F,t,.):, 720 #of Floors: Total Sq. Ft. 720 Height: 1 story Use.- accessQrV Type of Constructiom _w n ',CFIme 13. Has there been a previous application for a,Special Permit fromi the Planning Board on these 1 premises.? No If so,when and for what type of construction.? 14.,Section of Zoning Bylaw that Special Permit Is Beilng Requested 1 95.4.1 gjc)2.g 115. Petitioner and Landowner signature(s): Every application, for a Special Permit shall be made on this form, which is the official form of the Planning Board. Every application shall be filed with the Town Clerk's Offte. It shall be the responsibility of the titl n r t rnlshi all supporting documentation with this application. The, dated DOPY of this application received by the Town Clerk or, Planning Office does not absolve 'the applicant Yomthis Pespionsibi:lit,y. The, petitioner sihall be Pesponsiblefor all expenses for filing and legal notification. Failupt to comply with application Peq emir em nts,,, as cited hep,el"n and in the Planning, Boapd Rules and Regulations may Pesult 'in a dismissal by the Planning Board of this application, as incomplete. Petitioner's Signature: owl .......... Print or type n1ame here: kay, i n + Alisori-?SDarks, Owner's Signature: .............................................. Print or type name here: Kevin + Alisdh S parlks 161., Please list title of plans and documents you will be attaching to this application. Plot Plan of Land 3,25 Johnson 51, N dated 5/20/2021, scale 1" 20, D ra i Calc tat s for ll sizing Page 2 of 21 120 Main Street, Planning Dept., North Andover, Massachusetts,01845 Phone 978.688.9535 fax 978.688.9542, Web www.narthandoverm a' f, ING DEPARTMENT Building Conservation Health Planning Stevens Estate Zoning Certificationof Payme r c Tapes, Fees, Assessments, Betterments Municipal Charges The Town of North Andover General, Bylaw Chapter 29® , provides that any application for hermit, or license may be denied, suspended or revoked if the holder hereof has wiled or refused to pay any taxes,, fees, assessments, betterments or other municipal charges. signing this applicatU the appilicant represents th I he or she has paid all such taxes and fees,, ertify undier the penalties ofperjury that to the let of my k owl"e e and -fie ,, I have not neglected' or refused to pay any municipal taxes] fees,, assessments, betterments or any other municipal charge including amounts assessed under the provisions of section twenty-ores U, or, am not applyllng for a, license or permit with respect to, any activity, event or other matter which is the subject ' such license or,permit and which activity, event oir matter is carried t or exercised or is to be carr"Ied out or exercised n r about, real' estate whose owner has neglected or refused to, pay any local taxes, fees, assessments, betterments or any other municipal charge., Signed under,path: Mom' rY ,P Name 325 Johnson St, Nosh Andover, ,Address Does the Property Owner own any additional' property in North Andover (Yes or No,)*,? � . If yes, please list the property address of any additionalproperty. 5 f i Tarty Addressi f North Andover Tax Collector Signature Name Cate Sullivan Engineering c dWatershed SPecial. o 325 Johnson Street, Aft North.Andover PlanningBoall Fro, .: Jack Sulky Date: 2 0, 202 1, Subject.- Andover,—325 Johnson Street, North Written, � r for Project, Planning B err The following t,ten summary is prepared on behalf of the applicanlsl Kevin& Anson Sparks, in, support of construction of a 2 'x3 ' detached garage within the Watershed District. The project within the",Non- Disturbance zone". The entire lobs with. the "Non-Discharge zone" should be noted that,this lot was created 89 (Predating the watershed bylaw). e following iten.s as outfined in the Watershed Special.Perinit req.uirements are listed below(responses t required itenis are t 14 Encouraging,the mostappropriates land This' site is zonedresidential and the proposed site development Items �ted above are approprlate.16r this plarcel. The current owners have owned t i's parcelfor 32 years and seeking to make improvements to the property to further enjoy their home. . Preventing o ercr w ag,, of land, The proposed construction activities qf` n addition to the primary dwelling ies with zone setback "equirem,entsft all lot lines. 3. C s ry � t e vane of land, and buildings. The proposed site development will enhance surrounding r n and land values while being, aestheticall�pleasing Limited es b u M part � �" «� ile grading will be minor in Haters to make, transitions. s. . Lessening congestion oftr ,ff T nod„increase of :�o e4 n � h w is a singlefiamily dwellingwith. /invited trips per day. he s oproposedn � �e number of residents, there y exist g trqfficflow from the site will remain constant. 5. e l n g, undue concentration �of population x number(#`current residents will remain the samef6flowing completion qfthisprqject, 6. Providing .de q t' 1" it and air There it di �e impactto, current a kg and air and light 7. Reducing the hazards from fire and ter danger. PO Box '20,04 Woburn., MA01888 781,-85 - 64 e-maii.jaeKsul153@comcast.net There 1, e no increasen ar se e s f tom e or othe�rdangers. S., Assisting in, the Kcal provisions sp,ortatioln,, water, sewerage, schools, parks, and, otherpu,blic facilities.. This project, u7ill not impact the above noted public fiacilities andlor utilities. There will' not be a negative zinpact to the economics, of any,public utility. Controlling the use o 'bodies of water inch de' , a e c uryes, This project does not directly abut theLake and w not have a negative act on presentuses, q ~the Lake or tributaries,, thereto. 10. .educing the probability of losses resulting from s: This Property is not located w �hin a designated Flood Plain as, shownasthe latest-FIRM maps., The proposed construction will utilize rainy mitigation to, collectrecharge stormwater runqff the groundn,vater table. There w, ill'be no, increase o st :eater nodftom this site. There will be no increaSe in.1toodingprobability due to the develop °gent oJ'the property. 11. ee g and increasing the amenities ofthe Town This pro c increase the amenities of the Town through, an linprovementhe properly and additional x revenue due to the,new construction sessmen . The Planning Board,, in reviewin,gthis application, will. note that all threshold requirem,ents for granting i the Sped al Perinit,are met and/orexceeded. Eager written.docurnentabon is provided below(responses,� equ,ired items nital,ics) Writtencertification by a Registeredof ss a Engineer, or, r scientist educated in and possessing extensive experi,ence in the science of' hy r l y and hydrogeology, sa i g that there will not be any gig . c .e n t� th quantity water in or entering Lake Cochic ..e Eck. .1) ides,fiiingicides, chemicals, non organic p i e w �� � �� mall7tenance. Presently, there are no limitations on the e o quantity ' ers., f Siltation n ols are proposedat the limit Q f work during construction and until the site Isfinal stabilized y lcln �capedmeans, protect he lake and surroun,di'ngprolger,ties,,f 'ny potential impacts.runqf 3 w �✓�� ' g to dnw� a.+iM n has been provided I cco o increases in impervious r akm,,k, A.proposed gallon concrete drywell is proposed to co cilrecharge roQf nc ffrom the roof area of the proposed garage. The d ywell is sized to handle the 100 Year rain en (7,98� �I NO 's National Weather'Servieq) .14) The existing dive i ,ILL Bconnectedo the mania a sewer system oJ'thIS �c e ire therewill be no potential increase in nitrogen, levels aver the existing in background levels a the properly. This site d6es, not d ec abut the lake. Additionally, natural wooded bqffers will be retained within to the maximum extent &,asible. (7arefully,Manning we *nto, t � �� �� " � �! .��tp grading changes,and o a, h the exis,tin y "' " "g the grading changes , existing drainage watercourses will continue to function as in the undeveloped state. . Proofthat,,gars fis no reasonable alternative locat on outside the Non-Disttirbance and/or Non-Discharge Buffier Zones whichever is, applicable, for any discharge, struettire, activity, " use occur. withinThe entire, lot is the "Non- s h zone". An q1Jbrt was made to locate the garage beyond 50, ft?et.,ftoin the w,etlanlds while, complying v all requirements with zoning setbacks. PO Box 20 , . 8 7 5 -86 -�m. . *ac u ,53 c s . v"dense ofappro-val. by Mass DEP of'any inaustnal waste water treatment or d,isposal system or any waste, watertreatmerif of system 15 capacity. This, itern, dose not aply to, this' site., . vIdence that Ill. on-site operations �: � but limited.. , " m. c i s water water sposa fertilizer applications, and septic systems will not oasts concentrations of'Nitrogen in, groundwater, neater than the federal limit at thedown,gradient propertyboundary. The x�,� � De ng ALL BE connected to the rnun a sew,er s stem as part q this qppll cation, and the deed restriction only,allomn9 ., � gan c slo w-release nitro �n� h h rus gee duc o� fiertilizer use, ns,ure that biackgroundnitrogen levels, in the r undw -table W111 not be increased 5* r ections of downgradient concentrations of roe ho ors, and of r ev ; chemicals at property boundaries and other . ca io s deemed pertinent by the SPGA. T �will'be o �g en concentration ncen e above re erenc c e cals s outlined in the response to Item 4'above. If you should have questions or requi.re additional. lnforma lease feel free to cmtact me, 'Very Tr S Jac' l lfi n, P.E. Attachments (as noted) Cc* Kevinn and Alison S ark 'O Box 2OO4, Woburn, 188 78 5`'- 6 - .a1. cksuII53 c cast.,net TOWN of NORTH ANDOVER ABUTTER LIST REQUIREMENT: MGL 40A,Section 11 states in part"Parties in interest as used in this chapter shall mean the petitioner, abutters,owners of land directly opposite on any public or private way,and abutters to abutters within three hundred(300)feet of the property line of the pettitioner as they appear on the most recent applicable tax list,not withstanding that the land of any such owner is located in another city or town,the planning board of the city or town,and the planning hoard of every abutting city or town." SUBJECT PARCEL LOCATION OWNER ADDRESS CITY STATE ZIP 097.0-0072-0000.0 325 JOHNSON STREET KEVIN SPARKS 325 JOHNSON STREET NORTH ANDOVER MA 01845 PARCEL ID LOCATION OWNER ADDRESS CITY STATE ZIP 037.13-0024-0000.0 ABBOTT STREET RIDGEWOOD CEMETERY ASSOCIATION P O BOX 22 NORTH ANDOVER MA 01845 037.D-0025-0000.0 316 JOHNSON STREET REILLY,EUGENE,F. 316 JOHNSON STREET NORTH ANDOVER MA 01845 037.D-0026-0000.0 340 JOHNSON STREET MINICUCCI,DAVID,J. 340 JOHNSON STREET NORTH ANDOVER MA 01845 038.0-0015-0000.0 364 JOHNSON STREET BUITKUS,GREGORY 364 JOHNSON STREET NORTH ANDOVER MA 01845 097.0-0010-0000.0 107 SANDRA LANE LAPLANTE,JOSEPH E 107 SANDRA LANE NORTH ANDOVER MA 01845 097.0--0027-0000.0 301 JOHNSON STREET SALISBURY,CHARLES A 301 JOHNSON STREET NORTH ANDOVER MA 01845 097.0-0036-0000.0 290 JOHNSON STREET PACKARD,BOY❑ P O BOX 181 NORTH ANDOVER MA 01845 097.0-0073-0000.0 95 SANDRA LANE PAUL J.SALAFIA,JR. 95 SANDRA LANE NORTH ANDOVER MA 01845 097.0-0074-0000.0 83 SANDRA LANE C AND G REVOCABLE TRUST 83 SANDRA LANE NORTH ANDOVER MA 01845 097.0-0075-0000.0 67 SANDRA LANE BRENNAN,JAMES,H. 67 SANDRA LANE NORTH ANDOVER MA 01845 097.0-0091-0000.0 JOHNSON STREET SALISBURY,ELSIE H 301 JOHNSON STREET NORTH ANDOVER MA 01845 098.A-0043-0000.0 27 LISA LANE 27 LISA LANE REALTY TRUST 27 LISA LANE NORTH ANDOVER MA 01845 098.A-0044-0000.0 5 KIERAN ROAD DISHAW FAMILY INVESTMENT TRUST 5 KIERAN ROAD NORTH ANDOVER MA 01845 098,A-0045-0000.0 17 KIERAN ROAD THOMSON,RYAN F. 17 KIERAN ROAD NORTH ANDOVER MA 01845 098,A-0046-0000.0 27 KIERAN ROAD RITCHIE,LISA,A. 27 KIERAN ROAD NORTH ANDOVER MA 01845 098,A-0047-0000.0 37 KIERAN ROAD KESHIAN,JAMES H 37 KIERAN ROAD NORTH ANDOVER MA 01845 098.A-0048-0000.0 36 KIERAN ROAD FLANAGAN,WILLIAM M 36 KIERAN ROAD NORTH ANDOVER MA 01845 098.A-0049-0000.0 24 KIERAN ROAD KOLANO NOMINEE TRUST 24 KIERAN ROAD NORTH ANDOVER MA 01845 098.A-0103-0000.0 48 KIERAN ROAD DOUCETTE,PAUL T 48 KIERAN ROAD NORTH ANDOVER MA 01845 098.A-0112-0000.0 375 JOHNSON STREET LRP REALTY TRUST 375 JOHNSON STREET NORTH ANDOVER MA 01845 098.A-0113-0000.0 365 JOHNSON STREET JOHNSON,CHARLES ANDREW 365 JOHNSON STREET NORTH ANDOVER MA 01845 This mtries that the namappearkig an to records Of the AssesWW Office 000", CoMed by: ti Roof Area Of Galoage 1 P 1 , 000 Gallon r we w 0 24 If stone surrounding Subcat Reach Pon Link Drainage Diagram for 325 Johnson Street, NA Prepared by Sullivan Engineering Group, LLC 5/21/2021 HydroCAD®7.00 s/n 001433 ©1986-2003 Applied Microcomputer Systems 325 Johnson Street, NA Type/1/ 24-hr 2 Year Storm Rainfall=3.18" Prepared by Sullivan Engineering Group, LLC Page 2 HydroCAD®7.00 s/n 001433 © 1986-2003 Applied Microcomputer Systems 5/21/2021 Time span=5.00-24.00 hrs, dt=0.05 hrs, 381 points Runoff by SCS TR-20 method, UH=SCS Reach routing by Stor-Ind+Trans method - Pond routing by Stor-Ind method Subcatchment 1 S: Roof Area of Proposed Garage Runoff Area=720 sf Runoff Depth=2.89" Tc=6.0 min CN=98 Runoff=0.05 cfs 0.004 of Pond 1 P: 1,000 Gallon Drywell w/24" stone surPeak Elev=254.79' Storage=73 cf Inflow=0.05 cfs 0.004 of Outflow=0.00 cfs 0.004 of Total Runoff Area = 0.017 ac Runoff Volume = 0.004 of Average Runoff Depth = 2.89" 325 Johnson Street, NA Type 11124-hr 2 Year Storm Rainfall=3.18" Prepared by Sullivan Engineering Group, LLC Page 3 HydroCADO 7.00 s/n 001433 O 1986-2003 Applied Microcomputer Systems 5/21/2021 Subcatchment 1S: Roof Area of Proposed Garage Runoff = 0.05 cfs @ 12.09 hrs, Volume= 0.004 af, Depth= 2.89" Runoff by SCS TR-20 method, UH=SCS, Time Span= 5.00-24.00 hrs, dt= 0.05 hrs Type III 24-hr 2 Year Storm Rainfall=3.18" Area (sf) CN Description 720 98 Roof Area of Prop. Garage Tc Length Slope Velocity Capacity Description (min) (feet) (ft/ft) (ft/sec) (cfs) 6.0 Direct Entry, Subcatchment 1S: Roof Area of Proposed Garage Hydrograph 0.055 El Runoff 0.05 cfs 0.05 Type III 24-hr 2 Year Storm 0.045 Rainfall=3.18" 0.04 Runoff Area=720 sf 0.035 Runoff Volume=0.004 of Runoff Depth=2.89" 0.03 3 Tc=6.0 min LL 0.025 CN=98 0.02 0.015 0.01 0.005 0 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 Time (hours) 325 Johnson Street, NA Type/1/ 24-hr 2 Year Storm Rainfall=3.18" Prepared by Sullivan Engineering Group, LLC Page 4 HydroCAD®7.00 s/n 001433 © 1986-2003 Applied Microcomputer Systems 5/21/2021 Pond 1 P: 1,000 Gallon Drywell w/ 24" stone surrounding Sandy Loam - Rawl's Rate 1.02 in/hr) Inflow Area = 0.017 ac, Inflow Depth = 2.89" for 2 Year Storm event Inflow = 0.05 cfs @ 12.09 hrs, Volume= 0.004 of Outflow = 0.00 cfs @ 10.95 hrs, Volume= 0.004 af, Atten= 93%, Lag= 0.0 min Discarded = 0.00 cfs @ 10.95 hrs, Volume= 0.004 of Routing by Stor-Ind method, Time Span= 5.00-24.00 hrs, dt= 0.05 hrs Peak Elev= 254.79' @ 13.55 hrs Surf.Area= 140 sf Storage= 73 cf Plug-Flow detention time= 181.1 min calculated for 0.004 of(100% of inflow) Center-of-Mass det. time= 179.3 min ( 945.1 - 765.9 ) # Invert Avail.Storage Storage Description 1 253.80' 129 cf 9.67'W x 14.50'L x 3.50'H Prismatoid 491 cf Overall - 168 cf Embedded = 322 cf x 40.0% Voids 2 254.30' 168 cf 5.67'W x 10.50'L x 2.83'H Prismatoid Inside #1 297 cf Total Available Storage # Routing Invert Outlet Devices 1 Discarded 0.00' 0.001400 fpm Exfiltration over entire Surface area Discarded OutFlow Max=0.00 cfs @ 10.95 hrs HW=253.84' (Free Discharge) L1=Exfiltration (Exfiltration Controls 0.00 cfs) Pond 1 P: 1,000 Gallon Drywell w/ 24" stone surrounding Hydrograph EM Inflow 0.055 0.05 cfs IM Discarded Infl ow Area=O.0 17 ac 0.05 0.045 Peak Elev=254.79' 0.04 Storage=73 cf 0.035 U 0.03 3 ° 0.025 0.02 0.015 0.01 0.005 0.00 cfs 0 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 Time (hours) 325 Johnson Street, NA Type 111 24-hr 10 Year Storm Rainfall=5.03" Prepared by Sullivan Engineering Group, LLC Page 5 HydroCAD®7.00 s/n 001433 © 1986-2003 Applied Microcomputer Systems 5/21/2021 Time span=5.00-24.00 hrs, dt=0.05 hrs, 381 points Runoff by SCS TR-20 method, UH=SCS Reach routing by Stor-Ind+Trans method - Pond routing by Stor-Ind method Subcatchment 1 S: Roof Area of Proposed Garage Runoff Area=720 sf Runoff Depth=4.66" Tc=6.0 min CN=98 Runoff=0.08 cfs 0.006 of Pond 1 P: 1,000 Gallon Drywell w/24" stone suPeak Elev=255.55' Storage=143 cf Inflow=0.08 cfs 0.006 of Outflow=0.00 cfs 0.005 of Total Runoff Area = 0.017 ac Runoff Volume = 0.006 of Average Runoff Depth = 4.66" 325 Johnson Street, NA Type 11124-hr 10 Year Storm Rainfall=5.03" Prepared by Sullivan Engineering Group, LLC Page 6 HydroCADO 7.00 s/n 001433 O 1986-2003 Applied Microcomputer Systems 5/21/2021 Subcatchment 1S: Roof Area of Proposed Garage Runoff = 0.08 cfs @ 12.09 hrs, Volume= 0.006 af, Depth= 4.66" Runoff by SCS TR-20 method, UH=SCS, Time Span= 5.00-24.00 hrs, dt= 0.05 hrs Type III 24-hr 10 Year Storm Rainfall=5.03" Area (sf) CN Description 720 98 Roof Area of Prop. Garage Tc Length Slope Velocity Capacity Description (min) (feet) (ft/ft) (ft/sec) (cfs) 6.0 Direct Entry, Subcatchment 1S: Roof Area of Proposed Garage Hydrograph 0.085 Runoff 0.08 cfs 0.08 Type III 24-hr 10 Year Storm 0.075 0.07 Rainfall=5.03" 0.065 Runoff Area=720 sf 0.06 Runoff Volume=0.006 of 0.055 Runoff Depth=4.66" N 0.05 3 0.045 Tc=6.0 m i n LL 0.04 CN=98 0.035 0.03 0.025 0.02 0.015 0.01 0.005 IRE 02A2125. 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 Time (hours) 325 Johnson Street, NA Type/1/ 24-hr 10 Year Storm Rainfall=5.03" Prepared by Sullivan Engineering Group, LLC Page 7 HydroCAD®7.00 s/n 001433 © 1986-2003 Applied Microcomputer Systems 5/21/2021 Pond 1 P: 1,000 Gallon Drywell w/ 24" stone surrounding Sandy Loam - Rawl's Rate 1.02 in/hr) Inflow Area = 0.017 ac, Inflow Depth = 4.66" for 10 Year Storm event Inflow = 0.08 cfs @ 12.09 hrs, Volume= 0.006 of Outflow = 0.00 cfs @ 9.60 hrs, Volume= 0.005 af, Atten= 96%, Lag= 0.0 min Discarded = 0.00 cfs @ 9.60 hrs, Volume= 0.005 of Routing by Stor-Ind method, Time Span= 5.00-24.00 hrs, dt= 0.05 hrs Peak Elev= 255.55' @ 14.95 hrs Surf.Area= 140 sf Storage= 143 cf Plug-Flow detention time= 258.8 min calculated for 0.005 of(71% of inflow) Center-of-Mass det. time= 169.7 min ( 931.7 - 762.0 ) # Invert Avail.Storage Storage Description 1 253.80' 129 cf 9.67'W x 14.50'L x 3.50'H Prismatoid 491 cf Overall - 168 cf Embedded = 322 cf x 40.0% Voids 2 254.30' 168 cf 5.67'W x 10.50'L x 2.83'H Prismatoid Inside #1 297 cf Total Available Storage # Routing Invert Outlet Devices 1 Discarded 0.00' 0.001400 fpm Exfiltration over entire Surface area Discarded OutFlow Max=0.00 cfs @ 9.60 hrs HW=253.84' (Free Discharge) L1=Exfiltration (Exfiltration Controls 0.00 cfs) Pond 1 P: 1,000 Gallon Drywell w/ 24" stone surrounding Hydrograph EM Inflow 0.085 0.08 cfs IM Discarded 0.08 I of I ow Area=O.0 17 ac 0.075 0.07 Peak Elev=255-55' 0.065 Storage=143 cf 0.06 0.055 0.05 U 0.045 ° 0.04 0.035 0.03 0.025 0.02 0.015 0.01 0.00 cfs 0.005 0 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 Time (hours) 325 Johnson Street, NA Type/1/ 24-hr 25 Year Storm Rainfall=6.19" Prepared by Sullivan Engineering Group, LLC Page 8 HydroCAD®7.00 s/n 001433 © 1986-2003 Applied Microcomputer Systems 5/21/2021 Time span=5.00-24.00 hrs, dt=0.05 hrs, 381 points Runoff by SCS TR-20 method, UH=SCS Reach routing by Stor-Ind+Trans method - Pond routing by Stor-Ind method Subcatchment 1 S: Roof Area of Proposed Garage Runoff Area=720 sf Runoff Depth=5.77" Tc=6.0 min CN=98 Runoff=0.10 cfs 0.008 of Pond 1 P: 1,000 Gallon Drywell w/24" stone suPeak Elev=256.10' Storage=193 cf Inflow=0.10 cfs 0.008 of Outflow=0.00 cfs 0.005 of Total Runoff Area = 0.017 ac Runoff Volume = 0.008 of Average Runoff Depth = 5.77" 325 Johnson Street, NA Type 11124-hr 25 Year Storm Rainfall=6.19" Prepared by Sullivan Engineering Group, LLC Page 9 HydroCADO 7.00 s/n 001433 O 1986-2003 Applied Microcomputer Systems 5/21/2021 Subcatchment 1 S: Roof Area of Proposed Garage Runoff = 0.10 cfs @ 12.09 hrs, Volume= 0.008 af, Depth= 5.77" Runoff by SCS TR-20 method, UH=SCS, Time Span= 5.00-24.00 hrs, dt= 0.05 hrs Type III 24-hr 25 Year Storm Rainfall=6.19" Area (sf) CN Description 720 98 Roof Area of Prop. Garage Tc Length Slope Velocity Capacity Description (min) (feet) (ft/ft) (ft/sec) (cfs) 6.0 Direct Entry, Subcatchment 1 S: Roof Area of Proposed Garage Hydrograph 0.105 Runoff 0.10 cfs 0.1 0.095 Type III 24-hr 25 Year Storm 0.09 Rainfall=6.19" 0.085 0.08 Runoff Area=720 sf 0.075 0.07 Runoff Volume=0.008 of 0o 06 Runoff Depth=5.77" 3 0.055 TC=6.0 m i n .2 0.05 LL 0.045 CN=98 0.04 0.035 0.03 0.025 0.02 0.015 0.01 � 0.005 0 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 Time (hours) 325 Johnson Street, NA Type 111 24-hr 25 Year Storm Rainfall=6.19" Prepared by Sullivan Engineering Group, LLC Page 10 HydroCAD®7.00 s/n 001433 © 1986-2003 Applied Microcomputer Systems 5/21/2021 Pond 1 P: 1,000 Gallon Drywell w/ 24" stone surrounding Sandy Loam - Rawl's Rate 1.02 in/hr) Inflow Area = 0.017 ac, Inflow Depth = 5.77" for 25 Year Storm event Inflow = 0.10 cfs @ 12.09 hrs, Volume= 0.008 of Outflow = 0.00 cfs @ 8.90 hrs, Volume= 0.005 af, Atten= 97%, Lag= 0.0 min Discarded = 0.00 cfs @ 8.90 hrs, Volume= 0.005 of Routing by Stor-Ind method, Time Span= 5.00-24.00 hrs, dt= 0.05 hrs Peak Elev= 256.10' @ 15.59 hrs Surf.Area= 140 sf Storage= 193 cf Plug-Flow detention time= 260.2 min calculated for 0.005 of(59% of inflow) Center-of-Mass det. time= 155.7 min ( 916.6 - 760.9 ) # Invert Avail.Storage Storage Description 1 253.80' 129 cf 9.67'W x 14.50'L x 3.50'H Prismatoid 491 cf Overall - 168 cf Embedded = 322 cf x 40.0% Voids 2 254.30' 168 cf 5.67'W x 10.50'L x 2.83'H Prismatoid Inside #1 297 cf Total Available Storage # Routing Invert Outlet Devices 1 Discarded 0.00' 0.001400 fpm Exfiltration over entire Surface area Discarded OutFlow Max=0.00 cfs @ 8.90 hrs HW=253.84' (Free Discharge) L1=Exfiltration (Exfiltration Controls 0.00 cfs) Pond 1 P: 1,000 Gallon Drywell w/ 24" stone surrounding Hydrograph EM Inflow 0.10 cfs IM Discarded 0.105 0.1 1 nfl ow Area=O.0 17 ac 0.095 0.09 Peak Elev=256.10' 0.085 0.08 Storage=193 cf 0.075 0.07 0.065 4 0.06 0.055 0 0.05 U_0.045 0.04 0.035 0.03 0.025 0.02 0.015 0.01 0.00 cfs 0.005 0 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 Time (hours) 325 Johnson Street, NA Type 11124-hr 100 Year Storm Rainfall=7.98" Prepared by Sullivan Engineering Group, LLC Page 11 HydroCAD®7.00 s/n 001433 © 1986-2003 Applied Microcomputer Systems 5/21/2021 Time span=5.00-24.00 hrs, dt=0.05 hrs, 381 points Runoff by SCS TR-20 method, UH=SCS Reach routing by Stor-Ind+Trans method - Pond routing by Stor-Ind method Subcatchment 1 S: Roof Area of Proposed Garage Runoff Area=720 sf Runoff Depth=7.47" Tc=6.0 min CN=98 Runoff=0.13 cfs 0.010 of Pond 1 P: 1,000 Gallon Drywell w/24" stone suPeak Elev=256.99' Storage=275 cf Inflow=0.13 cfs 0.010 of Outflow=0.00 cfs 0.005 of Total Runoff Area = 0.017 ac Runoff Volume = 0.010 of Average Runoff Depth = 7.47" 325 Johnson Street, NA Type 11124-hr 100 Year Storm Rainfall=7.98" Prepared by Sullivan Engineering Group, LLC Page 12 HydroCADO 7.00 s/n 001433 O 1986-2003 Applied Microcomputer Systems 5/21/2021 Subcatchment 1 S: Roof Area of Proposed Garage Runoff = 0.13 cfs @ 12.09 hrs, Volume= 0.010 af, Depth= 7.47" Runoff by SCS TR-20 method, UH=SCS, Time Span= 5.00-24.00 hrs, dt= 0.05 hrs Type III 24-hr 100 Year Storm Rainfall=7.98" Area (sf) CN Description 720 98 Roof Area of Prop. Garage Tc Length Slope Velocity Capacity Description (min) (feet) (ft/ft) (ft/sec) (cfs) 6.0 Direct Entry, Subcatchment 1 S: Roof Area of Proposed Garage Hydrograph 0.14 Runoff 0.13 0.13 cfs 10 Type III 24-hr 100 Year Storm 0.12 Rainfall=7.98" 0.11 Runoff Area=720 sf 0.1 Runoff Volume=0.010 of 0.09 y Runoff Depth=7.47" o.os Tc=6.0 min 3 0.07 s CN=98 LL 0.06 0.05 0.04 0.03 0.02 0.01 0 U U 11111111 111, 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 Time (hours) 325 Johnson Street, NA Type 111 24-hr 100 Year Storm Rainfall=7.98" Prepared by Sullivan Engineering Group, LLC Page 13 HydroCAD®7.00 s/n 001433 © 1986-2003 Applied Microcomputer Systems 5/21/2021 Pond 1 P: 1,000 Gallon Drywell w/ 24" stone surrounding Sandy Loam - Rawl's Rate 1.02 in/hr) Inflow Area = 0.017 ac, Inflow Depth = 7.47" for 100 Year Storm event Inflow = 0.13 cfs @ 12.09 hrs, Volume= 0.010 of Outflow = 0.00 cfs @ 8.20 hrs, Volume= 0.005 af, Atten= 97%, Lag= 0.0 min Discarded = 0.00 cfs @ 8.20 hrs, Volume= 0.005 of Routing by Stor-Ind method, Time Span= 5.00-24.00 hrs, dt= 0.05 hrs Peak Elev= 256.99' @ 16.37 hrs Surf.Area= 140 sf Storage= 275 cf Plug-Flow detention time= 264.5 min calculated for 0.005 of(47% of inflow) Center-of-Mass det. time= 139.4 min ( 899.3 - 759.9 ) # Invert Avail.Storage Storage Description 1 253.80' 129 cf 9.67'W x 14.50'L x 3.50'H Prismatoid 491 cf Overall - 168 cf Embedded = 322 cf x 40.0% Voids 2 254.30' 168 cf 5.67'W x 10.50'L x 2.83'H Prismatoid Inside #1 297 cf Total Available Storage # Routing Invert Outlet Devices 1 Discarded 0.00' 0.001400 fpm Exfiltration over entire Surface area Discarded OutFlow Max=0.00 cfs @ 8.20 hrs HW=253.84' (Free Discharge) L1=Exfiltration (Exfiltration Controls 0.00 cfs) Pond 1 P: 1,000 Gallon Drywell w/ 24" stone surrounding Hydrograph Inflow 0.14 0.13 cfs IM Discarded 0.13 I of I ow Area=O.0 17 ac 0.12 Peak Elev=256-99' 0.11 0.1 Storage=275 cf 0.09 0.08 U 0.07 0 0.06 0.05 0.04 0.03 0.02 0.01 0.00 cfs 0 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 Time (hours)