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HomeMy WebLinkAbout20050808 DRAINAGE REPORT DRAINAGE REPORT 249 MARBLERIDGE ROAD NORTH ANDOVER, MASSACHUSETTS RECEIVED MAY 2 6 2005 NORTH ANDOVER PLANNING DEPARTMENT PREPARED FOR: Belford Construction, Inc. 1049 Turnpike Street North Andover,MA 01845 OF y C BENJAMIN C. '` 036000,JR. a CIVIL N0.45881 March 31,2005 Rev. May 25, 2005 TABLE OF CONTENTS INTRODUCTION 1 LOCUS MAPS 2 SITE SOILS MAP 3 DRAINAGE SYSTEM DESCRIPTION 4 PRE DEVELOPMENT ANALYSIS 5 POST DEVELOPMENT ANALYSIS 22 SUMMARY 58 APPENDIX 59 RUNOFF CURVE NUMBERS RAINFALL DATA MAPS INTRODUCTION The site described in this report is an existing single family residential lot with an existing single family home. The property is located at 249 Marbleridge Road,North Andover, MA. Lot size of the subject property is approximately 71,301 square feet. The site rises from the edge of Marbleridge Road approximately ten feet to where the house is located and then slopes gradually to the wetland located at the rear of the property. Site conditions consist of the dwelling,a garage,paved driveway areas, grass areas,and wetlands. The grass areas are maintained lawns and comprise most of the site. The wetland area is along the rear of the lot and is associated with an intermittent stream flowing along the property line. Proposed alterations to current conditions include razing the existing dwelling, dividing the property in two,and constructing two new dwellings with driveways and appurtenances.Portions of the property which are currently lawn will be converted to unused area to provide a buffer to the wetlands providing less runoff and nutrient loading than is occurring presently. Drainage calculations provided in this report depict both existing and proposed runoff for the 2 year, 10 year, and 100 year storms using the SCS TR20 Runoff Method. Soil classification on the site is Sutton series,which is classified as a SCS Hydrological Soil Group B.The proposed infiltration of roof runoff will reduce the amount of runoff from the site in all storms so that the proposed peak flow rates and volumes will be less than or equal to existing peak flow rates and volumes. In addition, a deep sump catch basin and a treatment Swale have been added adjacent to the proposed driveway for Lot 2.This system aids in the management of stormwater by diverting water that presently travels over a neighboring property to the rear of the project site. This system will also provide treatment of driveway runoff and produce a cleaner stormwater runoff than exists at the present time.. All regulations of the Town of North Andover have been incorporated herein. 1. USGS LOCUS MAP 45 y 1 GRE S 48.6 - •Nort' An o of r CQ _ H r, M'Is _ 2 SITE SOILS MAP 3 =CoC -ee SIB SrB 9 Mrti D CrtB j ;. E RdA Pa C ty .... O E StB gt � Wg 6 C � Mm6 ��- 5�6 MP PaD � I 00 O CoE I Wr6 D x J ie 3�- S _ Sfe �� c' AEG \ WsC \ \ Se Rd8 'Gl Stk W cl PaC WrC a n6 C PSD 3m RIB UC CpC PaB Ws6 Cad „Q J X00 3' d SUB :. t WrA �wc Cbi' V Sh6/: ... R Pa8 n Rye Pa8 ae` t Pb D SgC Sub 1 PcE O 9 CbC � v Mills fig' Pa6 Hill ggg RIB. RdA \.\ SrB Cab w aP P D ShC 16 top-, Sh CI PbC chR e 8 3 DRAINAGE SYSTEM DESCRIPTION The pre existing drainage area has been depicted as two separate drainage area flowing from the site. Area A-1 flows off the front of the property, along the roadway, and on to the neighboring property to the North. Drainage area A-2 drains to the west across the existing lawn and directly in to the wetlands at the rear of the property. The post development drainage has been combined in to one drainage area by constructing a swale on the North side of the property to divert the water from area A-1 in to drainage area A-2.The swale will also act as a treatment swale to reduce pollutants in the stormwater. The increases in runoff as a result of the increase in impervious area are being controlled by diverting all of the roof runoff in to infiltration systems. The infiltration of this runoff causes a decrease in post development rate and volume of water exiting the site. Pre and Post development drainage maps are included with this submittal.The drainage calculations are presented in the next section of this report. 4 PRE DEVELOPMENT ANALYSIS s PRE DE RE DEV 1P SUMMATION POND A-1 SUbC1t' Reach pn L1nk Drainage Diagram for 249 MARBLERIDGE ROAD,NORTH ANDOVER- PRE DEV Prepared by NEW ENGLAND ENGINEERING SERVICES INC. 5/25/2005 HydroCAD®7.10 s/n 002248 ©2005 HydroCAD Software Solutions LLC 6 249 MARBLERIDGE ROAD, NORTH ANDOVER - PRE Type /// 24-hr 2 YEAR Rainfall=3.20" Prepared by NEW ENGLAND ENGINEERING SERVICES INC. Page 7 H droCADO 7.10 s/n 002248 ©2005 H droCAD Software Solutions LLC 5/25/2005 Time span=1.00-48.00 hrs, dt=0.02 hrs, 2351 points Runoff by SCS TR-20 method, UH=SCS Reach routing by Stor-Ind+Trans method - Pond routing by Stor-Ind method Subcatchment A-1: PRE DEV Runoff Area=20,026 sf Runoff Depth=0.78" Flow Length=245' Tc=6.8 min CN=69 Runoff--0.36 cfs 1,301 cf Subcatchment A-2: PRE DEV Runoff Area=51,285 sf Runoff Depth=0.48" Flow Length=325' Tc=7.9 min CN=62 Runoff--0.41 cfs 2,056 cf Pond 1P: SUMMATION POND A-1 Peak Elev=0.00' Storage=0 cf Inflow--0.76 cfs 3,357 cf Outflow--0.75 cfs 3,357 cf Total Runoff Area= 71,311 sf Runoff Volume= 3,357 cf Average Runoff Depth= 0.56" 249 MARBLERIDGE ROAD, NORTH ANDOVER - PRE Type Ill 24-hr 2 YEAR Rainfall=3.20" Prepared by NEW ENGLAND ENGINEERING SERVICES INC. Page 8 HydroCAD®7.10 s/n 002248 ©2005_HydroCAD Software Solutions LLC 5/25/2005 Subcatchment A-1: PRE DEV Runoff = 0.36 cfs @ 12.11 hrs, Volume= 1,301 cf, Depth= 0.78" Runoff by SCS TR-20 method, UH=SCS, Time Span= 1.00-48.00 hrs, dt= 0.02 hrs Type III 24-hr 2 YEAR Rainfall=3.20" Area (sf) CN Description 15,897 61 >75% Grass cover, Good, HSG B 4,129 98 Paved parking & roofs 20,026 69 Weighted Average Tc Length Slope Velocity Capacity Description (min) (feet) (ft/ft) (ft/sec) (cfs) 5.6 100 0.0800 0.3 Sheet Flow, SHEET FLOW LAWN Grass: Short n= 0.150 P2= 3.20" 1.2 145 0.0800 2.0 Shallow Concentrated Flow, SHALLOW FLOW OVER LAWN Short Grass Pasture Kv= 7.0 fps 6.8 245 Total Subcatchment A-1: PRE DEV Hydrograph 0.38-: - -- -- - 13 Runoff 0. 0.36 -- - J0.34 _pe 111 24 ter 2 YEAR 0.32 -- - - - - -- -Rai nfaNT3.2-0" - 0.3 028 noff Area=20,026 sf-0.26- - - - 0.24 Runoffil/olume=1;3D1=cf = 0.22-: .22 - - U.2 p. - - 3 � - -- -- --- ' Runoff De th=0.78 U.,6 -F1oalll Length=245'-- 0.16 0.,4 _ 'Tc-68 min - 0.12 - CN=69- - 0.08 0.06 0.04- - 0.02 0 2 4 6 8 10 12 14 16 18 20 22 24 26 28 30 32 34 36 38 40 42 44 46 48 Time (hours) 249 MARBLERIDGE ROAD, NORTH ANDOVER - PRE Type !1124-hr 2 YEAR Rainfall=3.20" Prepared by NEW ENGLAND ENGINEERING SERVICES INC. Page 9 HydroCAD®7.10 s/n 002248 ©2005 HydroCAD Software Solutions LLC 5/25/2005 Subcatchment A-2: PRE DEV Runoff = 0.41 cfs @ 12.15 hrs, Volume= 2,056 cf, Depth= 0.48" Runoff by SCS TR-20 method, UH=SCS, Time Span= 1.00-48.00 hrs, dt= 0.02 hrs Type III 24-hr 2 YEAR Rainfall=3.20" Area (sf CN Description _ 49,575 61 >75% Grass cover, Good, HSG B 1,710 98 Paved parking & roofs 51,285 62 Weighted Average Tc Length Slope Velocity Capacity Description (min) (feet) (ftM (ft/sec) (cfs) 6.1 100 0.0650 0.3 Sheet Flow, SHEET FLOW LAWN Grass: Short n= 0.150 P2= 3.20" 1.8 225 0.0911 2.1 Shallow Concentrated Flow, SHALLOW FLOW OVER LAWN Short Grass Pasture Kv=7.0 fps 7.9 325 Total Subcatchment A-2: PRE DEV Hydrograph 0.46 _ - - ®Runoff 0.44 - 0.42 - X Y -hr p e-111-24 2 YEAR -- 0.38 0.36 - - - - - Rai[lftfl 3.20" _ 0.34 - Runoff Area=5 0.32 1,285 sf-_ 0.3 - ^ ' 0.2$ - - _Rur1off Vo[lurrie-2-05 0.26 - s_Cf-- 0.24 - _ aunoff Qepth=0.48" _ 0.22 - - ME 0.2 - FfOw Length=325' - 0.18 0.16 - Tc=7.9 min_ _ 0.14 ;, 0.12 CIS=62 _ 0.1-: - -- 0.08 0.06 0.04 0.02 0 2 4 6 8 10 12 14 16 18 20 22 24 26 28 30 32 34 36 38 40 42 44 46 48 Time (hours) 249 MARBLERIDGE ROAD, NORTH ANDOVER - PRE Type 11124-hr 2 YEAR Rainfall=3.20" Prepared by NEW ENGLAND ENGINEERING SERVICES INC. Page 10 HydroCAD®7.10 s/n 002248 ©2005 HydroCAD Software Solutions LLC 5/25/2005 Pond 1 P: SUMMATION POND A-1 Inflow Area= 71,311 sf, Inflow Depth = 0.56" for 2 YEAR event Inflow = 0.75 cfs @ 12.13 hrs, Volume= 3,357 cf Outflow = 0.75 cfs @ 12.13 hrs, Volume= 3,357 cf, Atten= 0%, Lag=0.0 min Primary = 0.75 cfs @ 12.13 hrs, Volume= 3,357 cf Routing by Stor-Ind method, Time Span= 1.00-48.00 hrs, dt= 0.02 hrs Peak Elev= 0.00' @ 12.13 hrs Surf.Area= 0 sf Storage= 0 cf Plug-Flow detention time= 0.0 min calculated for 3,355 cf(100% of inflow) Center-of-Mass det. time= 0.0 min ( 899.2- 899.2) Volume Invert Avail.Storage Storage Description #1 0.00' 1 cf Custom Stage Data Listed below Elevation Inc.Store Cum.Store (feet) (cubic-feet) (cubic-feet) 0.00 0 0 100.00 1 1 Device Routing Invert Outlet Devices #1 Primary 0.00' 999.0' long x 9.0' breadth Broad-Crested Rectangular Weir Head (feet) 0.20 0.40 0.60 0.80 1.00 1.20 1.40 1.60 1.80 2.00 2.50 3.00 3.50 4.00 4.50 5.00 5.50 Coef. (English) 2.46 2.55 2.70 2.69 2.68 2.68 2.67 2.64 2.64 2.64 2.65 2.64 2.65 2.65 2.66 2.67 2.69 Primary OutFlow Max=0.01 cfs @ 12.13 hrs HW=0.00' (Free Discharge) t--1=Broad-Crested Rectangular Weir (Weir Controls 0.01 cfs) 249 MARBLERIDGE ROAD, NORTH ANDOVER - PRE Type 11124-hr 2 YEAR Rainfall=3.20" Prepared by NEW ENGLAND ENGINEERING SERVICES INC. Page 11 HydroCAD®7.10 s/n 002248 ©2005 HydroCAD Software Solutions LLC 5/25/2005 Pond 1P: SUMMATION POND A-1 Hydrograph - ®Inflow o.7scrs" - ®Primary °'8 075 0.75 Anflow'Area=71 ,31-1 sf - - _ 0.7 I Peak Elev=0.00' - 0.65 0.6 - - - Stora e=O cf 0.55 0.5 0.45 " 0 0.4- - a 0.35 0.3 0.25 0.2 0.15 0.1 0.05 2 4 6 8 10 12 14 16 18 20 22 24 26 28 30 32 34 36 38 40 42 44 46 48 Time (hours) 249 MARBLERIDGE ROAD, NORTH ANDOVER - PRE Type I// 24-hr 10 YEAR Rainfall=4.60" Prepared by NEW ENGLAND ENGINEERING SERVICES INC. Page 12 HydroCAD®7.10 s/n 002248 ©2005 HydroCAD Software Solutions LLC 5/25/2005 Time span=1.00-48.00 hrs, dt=0.02 hrs, 2351 points Runoff by SCS TR-20 method, UH=SCS Reach routing by Stor-Ind+Trans method - Pond routing by Stor-Ind method Subcatchment A-1: PRE DEV Runoff Area=20,026 sf Runoff Depth=1.67" Flow Length=245' Tc=6.8 min CN=69 Runoff--0.85 cfs 2,790 cf Subcatchment A-2: PRE DEV Runoff Area=51,285 sf Runoff Depth=1.20" Flow Length=325' Tc=7.9 min CN=62 Runoff--1.38 cfs 5,120 cf Pond 1P: SUMMATION POND A-1 Peak Elev=0.00' Storage=0 cf Inflow=2.21 cfs 7,910 cf Outflow=2.21 cfs 7,910 cf Total Runoff Area= 71,311 sf Runoff Volume= 7,910 cf Average Runoff Depth = 1.33" 249 MARBLERIDGE ROAD, NORTH ANDOVER - PRE Type 11124-hr 10 YEAR Rainfall=4.60" Prepared by NEW ENGLAND ENGINEERING SERVICES INC. Page 14 HydroCAD®7.10 s/n 002248 ©2005 HydroCAD Software Solutions LLC 5/25/2005 Subcatchment A-2: PRE DEV Runoff = 1.38 cfs @ 12.13 hrs, Volume= 5,120 cf, Depth= 1.20" Runoff by SCS TR-20 method, UH=SCS, Time Span= 1.00-48.00 hrs, dt= 0.02 hrs Type III 24-hr 10 YEAR Rainfall=4.60" Area (sf) CN Description 49,575 61 >75% Grass cover, Good, HSG B 1,710 98 Paved parking & roofs 51,285 62 Weighted Average Tc Length Slope Velocity Capacity Description (min) (feet) (ft/ft) (fUsec) (cfs) 6.1 100 0.0650 0.3 Sheet Flow, SHEET FLOW LAWN Grass: Short n= 0.150 P2= 3.20" 1.8 225 0.0911 2.1 Shallow Concentrated Flow, SHALLOW FLOW OVER LAWN Short Grass Pasture Kv= 7.0 fps 7.9 325 Total Subcatchment A-2: PRE DEV Hydrograph Fla Runoff Type III 24-hr 10 YEAR Rainfall=4.60" Runoff Area-51,285 sf_ Runoff Volume=5,120 cf Runoff Depth=1.20" Flow Length=325' Tc=7.9 min CN=62 2 4 6 8 10 12 14 16 18 20 22 24 26 28 30 32 34 36 38 40 42 44 46 48 Time (hours) 249 MARBLERIDGE ROAD, NORTH ANDOVER - PRE Type 11124-hr 10 YEAR Rainfall=4.60" Prepared by NEW ENGLAND ENGINEERING SERVICES INC. Page 15 HydroCAD®7.10 s/n 002248 ©2005 HydroCAD Software Solutions LLC 5/25/2005 Pond 1 P: SUMMATION POND A-1 Inflow Area= 71,311 sf, Inflow Depth = 1.33" for 10 YEAR event Inflow = 2.21 cfs @ 12.12 hrs, Volume= 7,910 cf Outflow - 2.21 cfs @ 12.12 hrs, Volume= 7,910 cf, Atten= 0%, Lag= 0.0 min Primary = 2.21 cfs @ 12.12 hrs, Volume= 7,910 cf Routing by Stor-Ind method, Time Span= 1.00-48.00 hrs, dt= 0.02 hrs Peak Elev= 0.00' @ 12.12 hrs Surf.Area= 0 sf Storage= 0 cf Plug-Flow detention time= 0.0 min calculated for 7,907 cf(100% of inflow) Center-of-Mass det. time= 0.0 min (869,6- 869.6) Volume Invert Avail.Storage Storage Description #1 0.00' 1 cf Custom Stage Data Listed below Elevation Inc.Store Cum.Store (feet) (cubic-feet) (cubic-feet) 0.00 0 0 100.00 1 1 Device Routing Invert Outlet Devices #1 Primary 0.00' 999.0' long x 9.0' breadth Broad-Crested Rectangular Weir Head (feet) 0.20 0.40 0.60 0.80 1.00 1.20 1.40 1.60 1.80 2.00 2.50 3.00 3.50 4.00 4.50 5.00 5.50 Coef. (English) 2.46 2.55 2.70 2.69 2.68 2.68 2.67 2.64 2.64 2.64 2.65 2.64 2.65 2.65 2.66 2.67 2.69 Primary OutFlow Max=0.06 cfs @ 12.12 hrs HW=0.00' (Free Discharge) t-1=Broad-Crested Rectangular Weir (Weir Controls 0.06 cfs @ 0.1 fps) 249 MARBLERIDGE ROAD, NORTH ANDOVER - PRE Type 111 24-hr 10 YEAR Rainfall=4.60" Prepared by NEW ENGLAND ENGINEERING SERVICES INC. Page 16 HydroCAD®7.10 s/n 002248 ©2005 HydroCAD Software Solutions LLC 5/25/2005 Pond 1 P: SUMMATION POND A-1 Hydrograph ®Inflow 221ds1 ®Primary 2,2 i 1Inflow Area=71,311._sf_ 2 Peak Eiev=0.00' Storage=0 cf o , 2 4 6 8 10 12 14 16 18 20 22 24 26 28 30 32 34 36 38 40 42 44 46 48 Time (hours) 249 MARBLERIDGE ROAD, NORTH ANDOVER - PRE Type 11124-hr 100 Year Rainfall=6.40" Prepared by NEW ENGLAND ENGINEERING SERVICES INC. Page 17 HydroCADO 7.10 s/n 002248 ©2005 HydroCAD Software Solutions LLC 5/25/2005 Time span=1.00-48.00 hrs, dt=0.02 hrs, 2351 points Runoff by SCS TR-20 method, UH=SCS Reach routing by Stor-Ind+Trans method - Pond routing by Stor-Ind method Subcatchment A-1: PRE DEV Runoff Area=20,026 sf Runoff Depth=3.03" Flow Length=245' Tc=6.8 min CN=69 Runoff--1.58 cfs 5,054 cf Subcatchment A-2: PRE DEV Runoff Area=51,285 sf Runoff Depth=2.37" Flow Length=325' Tc=7.9 min CN=62 Runoff=2.96 cfs 10,123 cf Pond 1 P: SUMMATION POND A-1 Peak Elev=0.00' Storage=0 cf Inflow--4.51 cfs 15,176 cf Outflow--4.61 cfs 15,176 cf Total Runoff Area=71,311 sf Runoff Volume= 16,176 cf Average Runoff Depth = 2.65" 249 MARBLERIDGE ROAD, NORTH ANDOVER - PRE Type 11124-hr 100 Year Rainfall=6.40" Prepared by NEW ENGLAND ENGINEERING SERVICES INC. Page 18 HydroCAD®7.10 s/n 002248 ©2005 HydroCAD Software Solutions LLC 5/25/2005 Subcatchment A-1: PRE DEV Runoff = 1.58 cfs @ 12.10 hrs, Volume= 5,054 cf, Depth= 3.03" Runoff by SCS TR-20 method, UH=SCS, Time Span= 1.00-48.00 hrs, dt= 0.02 hrs Type III 24-hr 100 Year Rainfall=6.40" Area (sf) CN Description 15,897 61 >75% Grass cover, Good, HSG B 4,129 98 Paved parking & roofs 20,026 69 Weighted Average Tc Length Slope Velocity Capacity Description (min) (feet) (ft/ft) (ft/sec) (cfs) 5.6 100 0.0800 0.3 Sheet Flow, SHEET FLOW LAWN Grass: Short n= 0.150 P2= 3.20" 1.2 145 0.0800 2.0 Shallow Concentrated Flow, SHALLOW FLOW OVER LAWN Short Grass Pasture Kv=7.0 fps. 6.8 245 Total Subcatchment A-1: PRE DEV Hydrograph ®Runoff 1.58 aFs Type III 24-hr 100 Year Rainfall=6.40" Runoff Area=20,026 sf Runoff Volume=5,054-cf- Runoff Depth=3.03" Flow Length=245' Tc=6 ,8 min CN=69 0 2 4 6 8 10 12 14 16 18 20­22­24­'A­2''8'730 32 34 36 38 40 42 44 46 48 Time (hours) 249 MARBLERIDGE ROAD, NORTH ANDOVER - PRE Type 11124-hr 100 Year Rainfall=6.40" Prepared by NEW ENGLAND ENGINEERING SERVICES INC. Page 19 HydroCAD®7.10 s/n 002248 ©2005 HydroCAD Software Solutions LLC 5/25/2005 Subcatchment A-2: PRE DEV Runoff = 2.96 cfs @ 12.12 hrs, Volume= 10,123 cf, Depth= 2.37" Runoff by SCS TR-20 method, UH=SCS, Time Span= 1.00-48.00 hrs, dt= 0.02 hrs Type III 24-hr 100 Year Rainfall=6.40" Area (sf) CN Description 49,575 61 >75% Grass cover, Good, HSG B 1,710 98 Paved parking & roofs 51,285 62 Weighted Average Tc Length Slope Velocity Capacity Description (min) (feet) (ft/ft) (ft/sec) (cfs) 6.1 100 0.0650 0.3 Sheet Flow, SHEET FLOW LAWN - Grass: Short n= 0.150 P2= 3.20" 1.8 225 0.0911 2.1 Shallow Concentrated Flow, SHALLOW FLOW OVER LAWN Short Grass Pasture Kv= 7.0 fps 7.9 325 Total Subcatchment A-2: PRE DEV Hydrograph ®Runoff 2.96ds 3 Type 11124-hr 100_ Year Rainfall=6:40" Runoff Area=51,285 sf 2 Runoff,Volume=10,123-cf- Runoff Depth 2371" Flow Length=325' LL Tc=79 min 1 CN=62 0 2 4 6 8 10 12 14 16 18 20 22 24 26 28 30 32 34 36 38 40 42 44 46 48 Time (hours) 249 MARBLERIDGE ROAD, NORTH ANDOVER - PRE Type III 24-hr 100 Year Rainfall=6.40" Prepared by NEW ENGLAND ENGINEERING SERVICES INC. Page 21 HydroCAD®7.10 s/n 002248 ©2005 HydroCAD Software Solutions LLC 5/25/2005 Pond 1P: SUMMATION POND A-1 Hydrograph ®Inflow 5 4st crs` ®Primary 4.6, Inflow Area=71,311 sf 4 Peak Elev=0.00' Storage=0 cf 3 N O 2 BEEN 1 0 2 4 6 8 10 12 14 16 18 20 22 24 26 28 30 32 34 36 38 40 42 44 46 48 Time (hours) POST DEVELOPMENT ANALYSIS 22 SUBCATCH -1/A-2 ROO LOT 1 ROO LOT 2 INFILT ATOR LOT 1 INFILTRATOR LOT 2 1P SUMMATION POND tj Reach p� Link Drainage Diagram for 249 MARBLERIDGE ROAD,NORTH ANDOVER POST DEV Prepared by NEW ENGLAND ENGINEERING SERVICES INC. 5/25/2005 HydroCAD®7.10 s/n 002248 ©2005 HydroCAD Software Solutions LLC 23 249 MARBLERIDGE ROAD, NORTH ANDOVER POST D Type ///24-hr 2 Year Rainfall=3.20" Prepared by NEW ENGLAND ENGINEERING SERVICES INC. Page 25 HydroCAD®7.10 s/n 002248 ©2005 HydroCAD Software Solutions LLC 5/25/2005 Time span=0.00-48.00 hrs, dt=0.01 hrs, 4801 points Runoff by SCS TR-20 method, UH=SCS Reach routing by Stor-Ind+Trans method - Pond routing by Stor-Ind method Subcatchment A-112: SUBCATCH A-11A-2 Runoff Area=67,301 sf Runoff Depth=0.52" Flow Length=406' Tc=9.1 min CN=63 Runoff=0.59 cfs 2,913 cf Subcatchment R-1: ROOF LOT 1 Runoff Area=2,307 sf Runoff Depth=2.97" Flow Length=255' Tc=4.1 min CN=98 Runoff=0.18 cfs 570 cf Subcatchment R-2: ROOF LOT 2 Runoff Area=1,703 sf Runoff Depth=2.97" Flow Length=205' Tc=4.1 min CN=98 Runoff=0.13 cfs 421 cf Pond 1P: SUMMATION POND Peak EIev=0.00' Storage=0 of Inflow--0.59 cfs 2,913 cf Outflow--0.59 cfs 2,913 cf Pond 1-1: INFILTRATOR LOT 1 Peak EIev=100.45' Storage=571 cf Inflow=0.18 cfs 570 cf 0.5"x 45.0'Culvert Outflow=0.00 cfs 0 cf Pond 1-2: INFILTRATOR LOT 2 Peak Elev=97.96' Storage=421 cf Inflow--O.13 cfs 421 cf 0.5"x 40.0'Culvert Outflow=0.00 cfs 0 cf Total Runoff Area=71,311 sf Runoff Volume= 3,905 cf Average Runoff Depth= 0.66" 249 MARBLERIDGE ROAD, NORTH ANDOVER POST D Type 111 24-hr 2 Year Rainfall=3.20" Prepared by NEW ENGLAND ENGINEERING SERVICES INC. Page 26 HydroCAD®7.10 s/n 002248 ©2005 HydroCAD Software Solutions LLC 5/25/2005 Subcatchment A-112: SUBCATCH A-11A-2 Runoff = 0.59 cfs @ 12.16 hrs, Volume= 2,913 cf, Depth= 0.52" Runoff by SCS TR-20 method, UH=SCS, Time Span= 0.00-48.00 hrs, dt= 0.01 hrs Type III 24-hr 2 Year Rainfall=3.20" Area (sf) CN Description 62,843 61 >75% Grass cover, Good, HSG B 4,458 98 Paved parking & roofs 67,301 63 Weighted Average Tc Length Slope Velocity Capacity Description (min) (feet) (ft/ft) (ft/sec) (cfs) 6.3 100 0.0600 0.3 Sheet Flow, SHEET FLOW IN GRASS Grass: Short n= 0.150 P2= 3.20" 0.1 20 0.1750 2.9 Shallow Concentrated Flow,SHALLOW FLOW IN GRASS Short Grass Pasture Kv=7.0 fps 0.1 18 0.0555 4.8 Shallow Concentrated Flow, Flow over drive lot 1 Paved Kv= 20.3 fps 0.4 50 0.0700 1.9 Shallow Concentrated Flow,flow over gass to swale Short Grass Pasture Kv=7.0 fps 0.2 53 0.0613 4.3 1.45 Parabolic Channel,flow in swale along front prop. line W=2.00' D=0.25' Area=0.3 sf Perim=2.1' n= 0.025 Earth, grassed &winding 0.3 15 0.0133 0.8 0.00 Circular Channel (pipe), pipe under driveway Diam= 0.5" Area= 0.0 sf Perim= 0.1' r= 0.01' n= 0.010 PVC, smooth interior 0.2 15 0.0200 1.0 0.00 Circular Channel (pipe), 6" PVC Diam= 0.5" Area= 0.0 sf Perim=0.1' r= 0.01' n= 0.010 PVC, smooth interior 1.5 135 0.0074 1.5 0.50 Parabolic Channel,flow in swale along property line W=2.00' D=0.25' Area=0.3 sf Perim=2.1' n= 0.025 Earth, grassed &winding 9.1 406 Total 249 MARBLERIDGE ROAD, NORTH ANDOVER POST D Type 11124-hr 2 Year Rainfall=3.20" Prepared by NEW ENGLAND ENGINEERING SERVICES INC. Page 27 HydroCAD®7.10 s/n 002248 ©2005 HydroCAD Software Solutions LLC 5/25/2005 Subcatchment A-112: SUBCATCH A-1/A-2 Hydrograph 0.65 ®Runoff 0.59 0.6 Type ;III 24-hr 2 Year - 0.55 Rainfall=3.20''-- 0.5 0.45- Runoff-Area--67-301-sf - 0.4 Runoff Volume=2,913 cf - 0.35 Runoff Depth=0.52"- LL 0.3 Flow Length=406'-- 0.25 Tc=9.1 min_._ 0.2— CW63 - 0.15 0.1 0.05 0 2 4 6 8 10 12 14 16 18 20 22 24 26 28 30 32 34 36 38 40 42 44 46 48 Time (hours) 249 MARBLERIDGE ROAD, NORTH ANDOVER POST D Type 111 24-hr 2 Year Rainfall=3.20" Prepared by NEW ENGLAND ENGINEERING SERVICES INC. Page 28 HydroCAD®7.10 s/n 002248 ©2005 HydroCAD Software Solutions LLC 5/25/2005 Subcatchment R-1: ROOF LOT 1 Runoff = 0.18 cfs @ 12.06 hrs, Volume= 570 cf, Depth= 2.97" Runoff by SCS TR-20 method, UH=SCS, Time Span= 0.00-48.00 hrs, dt=0.01 hrs Type III 24-hr 2 Year Rainfall=3.20" Area (sf) CN Description 2,307 98 Paved parking & roofs Tc Length Slope Velocity Capacity Description (min) (feet) (ft/ft) (ft/sec) (cfs) 0.5 40 0.0250 1.3 Sheet Flow, ROOF Smooth surfaces n= 0.011 P2= 3.20" 3.6 215 0.0200 1.0 0.00 Circular Channel (pipe), PIPE TO INFILTRATOR Diam= 0.5" Area= 0.0 sf Perim= 0.1' r- 0.01' n= 0.010 PVC, smooth interior 4.1 255 Total Subcatchment R-1: ROOF LOT 1 Hydrograph 0.19 '_, �Runoff 0.18 0.t sas` 0.17 Type 11124-hr 2Year 0.16 0.15 - 0.14 Rainfall _3.20"_= Area 0.13 -Runoff- -x,3,07 sf. _ 0.12-: Runoff-Volume=5'70 cf- - .!? Runoff Depth-2.97' -- Ii 0.09 - - - 0.08 Flo- - w Length=255' - 0.07 - - 0.06. - 0.05 0.04 _ - CN=98 - 0.03- 0.02 - 0.01 ' 0 . 0 2 4 6 8 10 12 14 16 18 20 22 24 26 28 30 32 34 36 38 40 42 44 46 48 Time (hours) 249 MARBLERIDGE ROAD, NORTH ANDOVER POST D Type 111 24-hr 2 Year Rainfall=3.20" Prepared by NEW ENGLAND ENGINEERING SERVICES INC. Page 29 HydroCAD®7.10 sln 002248 ©2005 HydroCAD Software Solutions LLC 5/25/2005 Subcatchment R-2: ROOF LOT 2 Runoff = 0.13 cfs @ 12.06 hrs, Volume= 421 cf, Depth= 2.97" Runoff by SCS TR-20 method, UH=SCS, Time Span= 0.00-48.00 hrs, dt= 0.01 hrs Type III 24-hr 2 Year Rainfall=3.20" Area (sf) CN Description 1,703 98 Paved parking & roofs Tc Length Slope Velocity Capacity Description (min) (feet) (ft/ft) (ft/sec) (cfs) 0.2 40 0.2500 3.1 Sheet Flow, ROOF Smooth surfaces n= 0.011 P2= 3.20" 3.9 165 0.0100 0.7 0.00 Circular Channel (pipe), PIPE TO INFILTRATOR Diam= 0.5" Area= 0.0 sf Perim= 0.1' r= 0.01' n=0.010 PVC, smooth interior 4.1 205 Total Subcatchment R-2: ROOF LOT 2 Hydrograph 0.14 ®Runoff _ - 093ds` -- -- - 0.13 Type -111-24-hr 2 Year - 0.12 0.11 - -- Rainfall'-- Runoff Area 3 -201 -- - - 0.1 - - =1 ,70 sf 0.09- - --Ruflo#f Volume=42'1 -cf-- u 0.061 s 0.07 - Runoff Depth=2.97" _ LL 0.06 - - - Flow Length=205'-- 0.05 - 1 0.04 - Tc=4. -min - 0.03 N=98 - 0.02 0.0, o _ 0 2 4 6 8 10 12 14 16 18 20 22 24 26 28 30 32 34 36 38 40 42 44 46 48 Time (hours) 249 MARBLERIDGE ROAD, NORTH ANDOVER POST D Type 11124-hr 2 Year Rainfall=3.20" Prepared by NEW ENGLAND ENGINEERING SERVICES INC. Page 30 HydroCAD®7.10 s/n 002248 ©2005 HydroCAD Software Solutions LLC 5/25/2005 Pond 1 P: SUMMATION POND Inflow Area = 67,301 sf, Inflow Depth = 0.52" for 2 Year event Inflow = 0.59 cfs @ 12.16 hrs, Volume= 2,913 cf Outflow = 0.59 cfs @ 12.16 hrs, Volume= 2,913 cf, Atten= 0%, Lag= 0.0 min Primary = 0.59 cfs @ 12.16 hrs, Volume= 2,913 cf Routing by Stor-Ind method, Time Span=0.00-48.00 hrs, dt= 0.01 hrs Peak Elev= 0.00' @ 12.16 hrs Surf.Area= 0 sf Storage= 0 cf Plug-Flow detention time= (not calculated: outflow precedes inflow) Center-of-Mass det. time= 0.0 min ( 907.4-907.4) Volume Invert Avail.Storage Storage Description #1 0.00' 1 cf Custom Stage Data Listed below Elevation Inc.Store Cum.Store (feet) (cubic-feet) (cubic-feet) 0.00 0 0 10.00 1 1 Device Routing Invert Outlet Devices #1 Primary 0.00' 999.0' long x 9.0' breadth Broad-Crested Rectangular Weir Head (feet) 0.20 0.40 0.60 0.80 1.00 1.20 1.40 1.60 1.80 2.00 2.50 3.00 3.50 4.00 4.50 5.00 5.50 Coef. (English) 2.46 2.55 2.70 2.69 2.68 2.68 2.67 2.64 2.64 2.64 2.65 2.64 2.65 2.65 2.66 2.67 2.69 Primary OutFlow Max=0.05 cfs @ 12.16 hrs HW=0.00' (Free Discharge) t-1=Broad-Crested Rectangular Weir (Weir Controls 0.05 cfs @ 0.1 fps) 249 MARBLERIDGE ROAD, NORTH ANDOVER POST D Type 11124-hr 2 Year Rainfall=3.20" Prepared by NEW ENGLAND ENGINEERING SERVICES INC. Page 31 HydroCAD®7.10 s/n 002248 ©2005 HydroCAD Software Solutions LLC 5/25/2005 Pond 1 P: SUMMATION POND Hydrograph Fe Inflow 0.65 o.59is - ®Primary 0.6 059 Inflow Area=67,301 sf - 0.55 - Peak Elev=0:00' 0.5 0.45 - Storage=0 cf 0.4 0.35 3 ° 0.3 - - - - - - - 0.25-'' -- 0.2 -- - 0.15 -- 0.1 --- 0.05 '. 0 0 2 4 6 8 10 12 14 16 18 20 22 24 26 28 30 32 34 36 38 40 42 44 46 48 Time (hours) 249 MARBLERIDGE ROAD, NORTH ANDOVER POST D Type //I 24-hr 2 Year Rainfall=3.20" Prepared by NEW ENGLAND ENGINEERING SERVICES INC. Page 32 HydroCAD®7.10 s/n 002248 ©2005 HydroCAD Software Solutions LLC 5/25/2005 Pond 1-1: INFILTRATOR LOT 1 Inflow Area= 2,307 sf, Inflow Depth = 2.97" for 2 Year event Inflow = 0.18 cfs @ 12.06 hrs, Volume= 570 cf Outflow = 0.00 cfs @ 0.00 hrs, Volume= 0 cf, Atten= 100%, Lag= 0.0 min Primary = 0.00 cfs @ 0.00 hrs, Volume= 0 cf Routing by Stor-Ind method, Time Span= 0.00-48.00 hrs, dt= 0.01 hrs Peak Elev= 100.45' @ 24.25 hrs Surf.Area= 661 sf Storage= 571 cf Plug-Flow detention time= (not calculated: initial storage excedes outflow) Center-of-Mass det. time= (not calculated: no outflow) Volume Invert Avail.Storage Storage Description #1 99.00' 460 cf Custom Stage Data(Prismatic) Listed below 2,314 of Overall-781 cf Embedded = 1,533 cf x 30.0%Voids #2 99.50' 781 cf 44.6"W x 30.0"H x 30.25'L StormTech SC-740 x 4 Inside#1 1,241 cf Total Available Storage Elevation Surf.Area Inc.Store Cum.Store (feet) (sq-ft) (cubic-feet) (cubic-feet) 99.00 661 0 0 102.50 661 2,314 2,314 Device Routing Invert Outlet Devices #1 Primary 102.50' 0.5" x 45.0' long Culvert CPP, projecting, no headwall, Ke=0.900 Outlet Invert= 98.00' S= 0.1000? Cc=0.900 n= 0.010 PVC, smooth interior Primary OutFlow Max=0.00 cfs @ 0.00 hrs HW=99.00' (Free Discharge) t1=Culvert (Controls 0.00 cfs) 249 MARBLERIDGE ROAD, NORTH ANDOVER POST D Type 11124-hr 2 Year Rainfall=3.20" Prepared by NEW ENGLAND ENGINEERING SERVICES INC. Page 33 HydroCAD®7.10 s/n 002248 ©2005 HydroCAD Software Solutions LLC 5/25/2005 Pond 1-1: INFILTRATOR LOT 1 Hydrograph ®Inflow 0.19 o.tads - ®Primary 0.18 Inflow Area--2,307 sf 0.17 0.16 Peak-EIev-100.45'- - 0.14 - Storage 5 71 cf- 0.13 0.12 0.5" x 45-,00-Culvert - F 0.11 " 0.1 c 0.09z - - LL 0.08 0.07 0.06 0.05 0.04 0.03 _ 0.02 0.o.00 ers 0 0 2 4 6 8 10 12 14 16 18 20 22 24 26 28 30 32 34 36 38 40 42 44 46 48 Time (hours) 249 MARBLERIDGE ROAD, NORTH ANDOVER POST D Type 11124-hr 2 Year Rainfall=3.20" Prepared by NEW ENGLAND ENGINEERING SERVICES INC. Page 34 H droCAD®7.10 s/n 002248 ©2005 H droCAD Software Solutions LLC 5/25/2005 Pond 1-2: INFILTRATOR LOT 2 Inflow Area = 1,703 sf, Inflow Depth = 2.97" for 2 Year event Inflow = 0.13 cfs @ 12.06 hrs, Volume= 421 cf Outflow = 0.00 cfs @ 0.00 hrs, Volume= 0 cf, Atten= 100%, Lag= 0.0 min Primary = 0.00 cfs @ 0.00 hrs, Volume= 0 cf Routing by Stor-Ind method, Time Span= 0.00-48.00 hrs, dt= 0.01 hrs Peak Elev= 97.96' @ 24.25 hrs Surf.Area= 892 sf Storage=421 cf Plug-Flow detention time= (not calculated: initial storage excedes outflow) Center-of-Mass det. time= (not calculated: no outflow) Volume Invert Avail.Storage Storage Description #1 97.00' 483 cf Custom Stage Data(Prismatic) Listed below 2,078 cf Overall-470 cf Embedded = 1,609 cf x 30.0%Voids #2 97.50' 470 cf 28.9"W x 16.0"H x 75.59'L StormTech SC-310 x 3 Inside#1 952 cf Total Available Storage Elevation Surf.Area Inc.Store Cum.Store (feet) (sq-ft) (cubic-feet) (cubic-feet) 97.00 892 0 0 99.33 892 2,078 2,078 Device Routing Invert Outlet Devices #1 Primary 99.33' 0.5" x 40.0' long Culvert RCP, sq.cut end projecting, Ke= 0.500 Outlet Invert= 96.00' S= 0.0832'/' Cc=0.900 n= 0.010 PVC, smooth interior Primary OutFlow Max=0.00 cfs @ 0.00 hrs HW=97.00' (Free Discharge) t-1=Culvert (Controls 0.00 cfs) 249 MARBLERIDGE ROAD, NORTH ANDOVER POST D Type 11124-hr 2 Year Rainfall=3.20" Prepared by NEW ENGLAND ENGINEERING SERVICES INC. Page 35 HydroCAD®7.10 s/n 002248 ©2005 HydroCAD Software Solutions LLC 5/25/2005 Pond 1-2: INFILTRATOR LOT 2 Hydrograph ®Inflow 0.14 a�scrst: -- ®Primary 0.13 Inflow Area=1 ,703 sf 0.12 -Peak Elev=97.96' - 0.1 Storage421 cf 0 5"-x 40.0' Culvert 0.09 0.08- 0.07 0 LL 0.06 0.05 0.04- - 0.03 0.02 --- 0. 0 2 4 6 8 10 12 14 16 18 20 22 2'4..2'6 28 30 32 34 36 38 40 42 44 46 48 Time (hours) 249 MARBLERIDGE ROAD, NORTH ANDOVER POST Type /// 24-hr 10 Year Rainfall=4.60" Prepared by NEW ENGLAND ENGINEERING SERVICES INC. Page 36 HydroCAD®7.10 s/n 002248 ©2005 HydroCAD Software Solutions LLC 5/25/2005 Time span=0.00-48.00 hrs, dt=0.01 hrs, 4801 points Runoff by SCS TR-20 method, UH=SCS Reach routing by Stor-Ind+Trans method - Pond routing by Stor-Ind method Subcatchment A-1/2: SUBCATCH A-11A-2 Runoff Area=67,301 sf Runoff Depth=1.26" Flow Length=406' Tc=9.1 min CN=63 Runoff--1.86 cfs 7,077 cf Subcatchment R-1: ROOF LOT 1 Runoff Area=2,307 sf Runoff Depth=4.36" Flow Length=255' Tc=4.1 min CN=98 Runoff--0.25 cfs 839 cf Subcatchment R-2: ROOF LOT 2 Runoff Area=1,703 sf Runoff Depth=4.36" Flow Length=205' Tc=4.1 min CN=98 Runoff=0.19 cfs 619 cf Pond 1 P: SUMMATION POND Peak EIev=0.00' Storage=0 cf Inflow--1.86 cfs 7,077 cf Outflow--1.86 cfs 7,077 cf Pond 1-1: INFILTRATOR LOT 1 Peak EIev=101.06' Storage=839 cf Inflow--0.25 cfs 839 cf 0.5"x 45.0'Culvert Outflow=0.00 cfs 0 cf Pond 1-2: INFILTRATOR LOT 2 Peak EIev=98.32' Storage=619 cf Inflow=0.19 cfs 619 cf 0.5"x 40.0'Culvert Outflow--0.00 cfs 0 cf Total Runoff Area=71,311 sf Runoff Volume=8,535 cf Average Runoff Depth = 1.44" 249 MARBLERIDGE ROAD, NORTH ANDOVER POST Type 11124-hr 10 Year Rainfall=4.60" Prepared by NEW ENGLAND ENGINEERING SERVICES INC. Page 37 HydroCAD®7.10 s/n 002248 ©2005 HydroCAD Software Solutions LLC 5/25/2005 Subcatchment A-112: SUBCATCH A-11A-2 Runoff = 1.86 cfs @ 12.14 hrs, Volume= 7,077 cf, Depth= 1.26" Runoff by SCS TR-20 method, UH=SCS, Time Span= 0.00-48.00 hrs, dt= 0.01 hrs Type III 24-hr 10 Year Rainfall=4.60" Area (sf) CN Description 62,843 61 >75% Grass cover, Good, HSG B 4,458 98 Paved parking & roofs 67,301 63 Weighted Average Tc Length Slope Velocity Capacity Description (min) (feet) (ft/ft) (ft/sec) (cfs) 6.3 100 0.0600 0.3 Sheet Flow, SHEET FLOW IN GRASS Grass: Short n=0.150 P2= 3.20" 0.1 20 0.1750 2.9 Shallow Concentrated Flow, SHALLOW FLOW IN GRASS Short Grass Pasture Kv= 7.0 fps 0.1 18 0.0555 4.8 Shallow Concentrated Flow, Flow over drive lot 1 Paved Kv= 20.3 fps 0.4 50 0.0700 1.9 Shallow Concentrated Flow,flow over gass to swale Short Grass Pasture Kv=7.0 fps 0.2 53 0.0613 4.3 1.45 Parabolic Channel,flow in swale along front prop. line W=2.00' D=0.25' Area=0.3 sf Perim=2.1' n= 0.025 Earth, grassed &winding 0.3 15 0.0133 0.8 0.00 Circular Channel (pipe), pipe under driveway Diam= 0.5" Area= 0.0 sf Perim= 0.1' r= 0.01' n= 0.010 PVC, smooth interior 0.2 15 0.0200 1.0 0.00 Circular Channel (pipe), 6" PVC Diam= 0.5" Area=0.0 sf Perim= 0.1' r- 0.01' n= 0.010 PVC, smooth interior 1.5 135 0.0074 1.5 0.50 Parabolic Channel,flow in swale along property line W=2.00' D=0.25' Area=0.3 sf Perim=2.1' n= 0.025 Earth, grassed &winding 9.1 406 Total 249 MARBLERIDGE ROAD, NORTH ANDOVER POST Type Ill 24-hr 10 Year Rainfall=4.60" Prepared by NEW ENGLAND ENGINEERING SERVICES INC. Page 38 HydroCAD®7.10 s/n 002248 ©2005 HydroCAD Software Solutions LLC 5/25/2005 Subcatchment A-112: SUBCATCH A-11A-2 Hydrograph 2 ®Runoff Issas; Type III 24-hr 10 Year Rainfall=4.60" Runoff Area=67,301 sf Runoff Volume=7,077 cf Runoff-Depth=1.2S"- ' Flow Length=406' Tc=9.1 m i n CN=63 0 2 4 6 8 10 12 14 16 18 20 22 24 26 28 30 32 34 36 38 40 42 44 46 48 Time (hours) 249 MARBLERIDGE ROAD, NORTH ANDOVER POST Type 11124-hr 10 Year Rainfall=4.60" Prepared by NEW ENGLAND ENGINEERING SERVICES INC. Page 39 HydroCAD®7.10 s/n 002248 ©2005 HydroCAD Software Solutions LLC 5/25/2005 Subcatchment R-1: ROOF LOT 1 Runoff = 0.25 cfs @ 12.06 hrs, Volume= 839 cf, Depth= 4.36" Runoff by SCS TR-20 method, UH=SCS, Time Span= 0.00-48.00 hrs, dt= 0.01 hrs Type III 24-hr 10 Year Rainfall=4.60" Area (sf) CN Description 2,307 98 Paved parking & roofs Tc Length Slope Velocity Capacity Description (min) (feet) (ft/ft) (ft/sec) (cfs) 0.5 40 0.0250 1.3 Sheet Flow, ROOF Smooth surfaces n= 0.011 P2= 3.20" 3.6 215 0.0200 1.0 0.00 Circular Channel (pipe), PIPE TO INFILTRATOR Diam= 0.5" Area= 0.0 sf Perim= 0.1' r- 0.01' n= 0.010 PVC, smooth interior 4.1 255 Total Subcatchment R-1: ROOF LOT 1 Hydrograph 0.28 -- ®Runoff 0.26 - 02 5ds` 0.24 - .T yp a-III 24-hr 10-Yea - - - 0.22 Rain .all=4.60" 0.2 - Run off Area, 307 sf - 0.18 0.16 - Runoff Volume=8;39 . - - - _ 0 0.14 Runoff Depth 4 36" u 0.12 - - -Flow Lentgth�=255'-- 0.1 0.0a Tc=4.1 min - 0.06 - CN=98 0.04 0.02 0 0 2 4 6 8 10 12 14 16 18 20 22 24 26 28 30 32 34 36 38 40 42 44 46 48 Time (hours) 249 MARBLERIDGE ROAD, NORTH ANDOVER POST Type 11124-hr 10 Year Rainfall=4.60" Prepared by NEW ENGLAND ENGINEERING SERVICES INC. Page 40 HydroCAD®7.10 s/n 002248 ©2005 HydroCAD Software Solutions LLC 5/25/2005 Subcatchment R-2: ROOF LOT 2 Runoff = 0.19 cfs @ 12.06 hrs, Volume= 619 cf, Depth= 4.36" Runoff by SCS TR-20 method, UH=SCS, Time Span= 0.00-48.00 hrs, dt= 0.01 hrs Type III 24-hr 10 Year Rainfall=4.60" Area (sf) CN Description 1,703 98 Paved parking &roofs Tc Length Slope Velocity Capacity Description (min) (feet) (fVft) (ft/sec) (cfs) 0.2 40 0.2500 3.1 Sheet Flow, ROOF Smooth surfaces n= 0.011 P2= 3.20" 3.9 165 0.0100 0.7 0.00 Circular Channel (pipe), PIPE TO INFILTRATOR Diam= 0.5" Area= 0.0 sf Perim= 0.1' r- 0.01' n=0.010 PVC, smooth interior 4.1 205 Total Subcatchment R-2: ROOF LOT 2 Hydrograph 0.21 0.2 - �Runoff 0.19ds. - --- - _ 0.19 - - -- Type 11124-h r 10 Yeah0.18- -- 0.16 - - - - Rai-nfa1IF4.60" - 0.15 0.14 _ _ _Runoff_Area=1,703 sf.- 0.13 - - _ 0.12 - - Runoff Volume=6;19 cf-_ -_ , _ _ _ _ - - 0.11 0.1 -- - :_ Runoff-Depth=4.36., IL 0.09 - _ 0.08 -Flov�ten th=205' _ 0.07' - 0.06 Tc=4.1 -min - 0.05-: - CN=98 _ 0.04 - _ 0.03- - 0.02 - 0.01 0 0 2 4 6 8 10 12 14 16 18 20 22 24 26 28 30 32 34 36 38 40 42 44 46 48 Time (hours) 249 MARBLERIDGE ROAD, NORTH ANDOVER POST Type 11124-hr 10 Year Rainfall=4.60" Prepared by NEW ENGLAND ENGINEERING SERVICES INC. Page 41 HydroCAD®7.10 s/n 002248 ©2005 HydroCAD Software Solutions LLC 5/25/2005 Pond 1P: SUMMATION POND Inflow Area= 67,301 sf, Inflow Depth = 1.26" for 10 Year event Inflow = 1.86 cfs @ 12.14 hrs, Volume= 7,077 cf Outflow = 1.86 cfs @ 12.14 hrs, Volume= 7,077 cf, Atten= 0%, Lag= 0.0 min Primary = 1.86 cfs @ 12.14 hrs, Volume= 7,077 cf Routing by Stor-Ind method, Time Span= 0.00-48.00 hrs, dt= 0.01 hrs Peak Elev= 0,00' @ 12.14 hrs Surf,Area= 0 sf Storage= 0 cf Plug-Flow detention time= 0.0 min calculated for 7,076 cf(100% of inflow) Center-of-Mass det. time= 0.0 min (875.1 - 875.1 ) Volume Invert Avail.Storage Storage Description #1 0.00' 1 cf Custom Stage Data Listed below Elevation Inc.Store Cum.Store (feet) (cubic-feet) (cubic-feet) 0.00 0 0 10.00 1 1 Device Routing Invert Outlet Devices #1 Primary 0.00' 999.0' long x 9.0' breadth Broad-Crested Rectangular Weir Head (feet) 0.20 0.40 0.60 0.80 1.00 1.20 1.40 1.60 1.80 2.00 2.50 3.00 3.50 4.00 4.50 5.00 5.50 Coef. (English) 2.46 2.55 2.70 2.69 2.68 2.68 2.67 2.64 2.64 2.64 2.65 2.64 2.65 2.65 2.66 2.67 2.69 Primary OutFlow Max=0.29 cfs @ 12.14 hrs HW=0.00' (Free Discharge) t--1=Broad-Crested Rectangular Weir (Weir Controls 0.29 cfs @ 0.1 fps) 249 MARBLERIDGE ROAD, NORTH ANDOVER POST Type Ill 24-hr 10 Year Rainfall=4.60" Prepared by NEW ENGLAND ENGINEERING SERVICES INC. Page 42 HydroCAD®7.10 s/n 002248 ©2005 HydroCAD Software Solutions LLC 5/25/2005 Pond 1P: SUMMATION POND Hydrograph _ ®Inflow 2 reads ®Primary '"� Inflow Area=67,301 sf Peak Elev=0.00' Storage=0 cif 3 , li. - 0 0 2 4 6 8 10 12 14 16 18 20 22 24 26 28 30 32 34 36 38 40 42 44 46 48 Time (hours) 249 MARBLERIDGE ROAD, NORTH ANDOVER POST Type 11124-hr 10 Year Rainfall=4.60" Prepared by NEW ENGLAND ENGINEERING SERVICES INC. Page 43 HydroCAD®7.10 s/n 002248 ©2005 HydroCAD Software Solutions LLC 5/25/2005 Pond 1-1: INFILTRATOR LOT 1 Inflow Area = 2,307 sf, Inflow Depth = 4.36" for 10 Year event Inflow = 0.25 cfs @ 12.06 hrs, Volume= 839 cf Outflow = 0.00 cfs @ 0.00 hrs, Volume= 0 cf, Atten= 100%, Lag= 0.0 min Primary = 0.00 cfs @ 0.00 hrs, Volume= 0 cf Routing by Stor-Ind method, Time Span= 0.00-48.00 hrs, dt= 0.01 hrs Peak Elev= 101.06' @ 24.25 hrs Surf.Area= 661 sf Storage= 839 cf Plug-Flow detention time= (not calculated: initial storage excedes outflow) Center-of-Mass det. time= (not calculated: no outflow) Volume Invert Avail.Storage Storage Description #1 99.00' 460 cf Custom Stage Data(Prismatic) Listed below 2,314 cf Overall -781 cf Embedded = 1,533 cf x 30.0%Voids #2 99.50' 781 cf 44.6"W x 30.0"H x 30.251 StormTech SC-740 x 4 Inside#1 1,241 cf Total Available Storage Elevation Surf.Area Inc.Store Cum.Store (feet) (sq-ft) (cubic-feet) (cubic-feet) 99.00 661 0 0 102.50 661 2,314 2,314 Device Routing Invert Outlet Devices #1 Primary 102.50' 0.5" x 45.0' long Culvert CPP, projecting, no headwall, Ke= 0.900 Outlet Invert= 98.00' S= 0.10007 Cc=0.900 n= 0.010 PVC, smooth interior Primary OutFlow Max=0.00 cfs @ 0.00 hrs HW=99.00' (Free Discharge) L1=Culvert (Controls 0.00 cfs) 249 MARBLERIDGE ROAD, NORTH ANDOVER POST Type I// 24-hr 10 Year Rainfall=4.60" Prepared by NEW ENGLAND ENGINEERING SERVICES INC. Page 44 H droCAD®7.10 s/n 002248 ©2005 H droCAD Software Solutions LLC 5/25/2005 Pond 1-1: INFILTRATOR LOT 1 Hydrograph ®inflow 0.28 -- 0.25 cis - - - - ®Primary 0.26 - _ Inflow Area=2307-sf - 0.24 0.22 - -- - Peak_Elev=101-.06' 0.2 Storage-839 cf 0.18 - 0.5" x 45.0`Culvert . F 0.16 - --- 0.14 - o LL 0.12 0.1 0.08 - - -- 0.04 - -0.024- - 0 0 2 4 6 8 10 12 14 16 18 20 22"214. 26 28 30 32 34 36 38 40 42 44 46 48 Time (hours) 249 MARBLERIDGE ROAD, NORTH ANDOVER POST Type Ill 24-hr 10 Year Rainfall=4.60" Prepared by NEW ENGLAND ENGINEERING SERVICES INC. Page 45 HydroCAD®7.10 s/n 002248 ©2005 HydroCAD Software Solutions LLC 5/25/2005 Pond 1-2: INFILTRATOR LOT 2 Inflow Area= 1,703 sf, Inflow Depth = 4.36" for 10 Year event Inflow - 0.19 cfs @ 12.06 hrs, Volume= 619 cf Outflow = 0.00 cfs @ 0.00 hrs, Volume= 0 cf, Atten= 100%, Lag= 0.0 min Primary - 0.00 cfs @ 0.00 hrs, Volume= 0 cf Routing by Stor-Ind method, Time Span= 0.00-48.00 hrs, dt= 0.01 hrs Peak Elev= 98.32' @ 24.25 hrs Surf.Area= 892 sf Storage=619 cf Plug-Flow detention time= (not calculated: initial storage excedes outflow) Center-of-Mass det. time= (not calculated: no outflow) Volume Invert Avail.Storage Storage Description #1 97.00' 483 cf Custom Stage Data (Prismatic) Listed below 2,078 cf Overall-470 cf Embedded = 1,609 cf x 30.0%Voids #2 97.50' 470 cf 28.9'W x 16.0"H x 75.59%StormTech SC-310 x 3 Inside#1 952 cf Total Available Storage Elevation Surf.Area Inc.Store Cum.Store (feet) (sq-ft) (cubic-feet) (cubic-feet) 97.00 892 0 0 99.33 892 2,078 2,078 Device Routing_ Invert Outlet Devices #1 Primary 99.33' 0.5" x 40.0' long Culvert RCP, sq.cut end projecting, Ke= 0.500 Outlet Invert= 96.00' S= 0.0832 ? Cc=0.900 n= 0.010 PVC, smooth interior Primary OutFow Max=0.00 cfs @ 0.00 hrs HW=97.00' (Free Discharge) t--1=Culvert (Controls 0.00 cfs) 249 MARBLERIDGE ROAD, NORTH ANDOVER POST Type 11124-hr 10 Year Rainfall=4.60" Prepared by NEW ENGLAND ENGINEERING SERVICES INC. Page 46 HydroCAD®7.10 s/n 002248 4 2005 HydroCAD Software Solutions LLC 5/25/2005 Pond 1-2: INFILTRATOR LOT 2 Hydrograph 0.21 ®inflow Inflow Area-1,703-0 IM Primary 0.19 0.2 - 0.17-: -- - -P,-ea{ -Elev--98.32,' 0.,6 0.15 Storage=61-9 cf 0.,4 0.13 - - 0.V x 40.01-Gulveft - j 0.12 0.11: 0.1 M 0.09 - - - 0.08 - 0.07 0.06 - 0.05 - 0.04 0.03 0.02 0.171 . 00 ds; 0 0 2 4 6 8 10 12 14 16 18 20 22 24 26 28 30 32 34 36 38 40 42 44 46 48 Time (hours) 249 MARBLERIDGE ROAD, NORTH ANDOVER POST Type 11124-hr 100 year Rainfall=6.40" Prepared by NEW ENGLAND ENGINEERING SERVICES INC. Page 47 HydroCADO 7.10 s/n 002248 ©2005 HydroCAD Software Solutions LLC 5/25/2005 Time span=0.00-48.00 hrs, dt=0.01 hrs, 4801 points Runoff by SCS TR-20 method, UH=SCS Reach routing by Stor-Ind+Trans method - Pond routing by Stor-Ind method Subcatchment A-112: SUBCATCH A-1 1A-2 Runoff Area=67,301 sf Runoff Depth=2.46" Flow Length=406' Tc=9.1 min CN=63 Runoff--3.90 cfs 13,798 cf Subcatchment R-1: ROOF LOT 1 Runoff Area=2,307 sf Runoff Depth=6.16" Flow Length=255' Tc=4.1 min CN=98 Runoff--0.36 cfs 1,185 cf Subcatchment R-2: ROOF LOT 2 Runoff Area=1,703 sf Runoff Depth=6.16" Flow Length=205' Tc=4.1 min CN=98 Runoff--0.26 cfs 874 cf Pond 1P: SUMMATION POND Peak EIev=0.01' Storage=0 cf Inflow=3.90 cfs 13,798 cf Outflow=3.90 cfs 13,798 cf Pond I-1: INFILTRATOR LOT 1 Peak EIev=102.22' Storage=1,185 cf Inflow--0.36 cfs 1,185 cf 0.5"x 45.0'Culvert Outflow--0.00 cfs 0 cf Pond 1-2: INFILTRATOR LOT 2 Peak EIev=99.04' Storage=874 cf Inflow--0.26 cfs 874 cf 0.5"x 40.0' Culvert Outflow=0.00 cfs 0 cf Total Runoff Area=71,311 sf Runoff Volume= 15,867 cf Average Runoff Depth= 2.67" 249 MARBLERIDGE ROAD, NORTH ANDOVER POST Type 11124-hr 900 year Rainfall=6.40" Prepared by NEW ENGLAND ENGINEERING SERVICES INC. Page 48 HydroCADO 7.10 s/n 002248 ©2005 HydroCAD Software Solutions LLC 5/25/2005 Subcatchment A-1/2: SUBCATCH A-11A-2 Runoff = 3.90 cfs @ 12.13 hrs, Volume= 13,798 cf, Depth= 2.46" Runoff by SCS TR-20 method, UH=SCS, Time Span= 0.00-48.00 hrs, dt=0.01 hrs Type ill 24-hr 100 year Rainfall=6.40" Area (sf) CN Description 62,843 61 >75% Grass cover, Good, HSG B 4,458 98 Paved parking & roofs 67,301 63 Weighted Average Tc Length Slope Velocity Capacity Description (min) (feet) (ft/ft) (ft/sec) (cfs) 6.3 100 0.0600 0.3 Sheet Flow, SHEET FLOW IN GRASS Grass: Short n= 0.150 P2= 3.20" 0.1 20 0.1750 2.9 Shallow Concentrated Flow, SHALLOW FLOW IN GRASS Short Grass Pasture Kv=7.0 fps 0.1 18 0.0555 4.8 Shallow Concentrated Flow, Flow over drive lot 1 Paved Kv= 20.3 fps 0.4 50 0.0700 1.9 Shallow Concentrated Flow,flow over gass to swale Short Grass Pasture Kv=7.0 fps 0.2 53 0.0613 4.3 1.45 Parabolic Channel,flow in swale along front prop. line W=2.00' D=0.25' Area=0.3 sf Perim=2.1' n= 0.025 Earth, grassed &winding 0.3 15 0.0133 0.8 0.00 Circular Channel (pipe), pipe under driveway Diam=0.5" Area= 0.0 sf Perim= 0.1' r= 0.01' n= 0.010 PVC, smooth interior 0.2 15 0.0200 1.0 0.00 Circular Channel(pipe), 6" PVC Diam=0.5" Area= 0.0 sf Perim= 0.1' r- 0.01' n=0.010 PVC, smooth interior 1.5 135 0.0074 1.5 0.50 Parabolic Channel,flow in swale along property line W=2.00' D=0.25' Area=0.3 sf Perim=2.1' n= 0.025 Earth, grassed &winding 9.1 406 Total - 249 MARBLERIDGE ROAD, NORTH ANDOVER POST Type 11124-hr 100 year Rainfall=6.40" Prepared by NEW ENGLAND ENGINEERING SERVICES INC. Page 49 HydroCAD®7.10 s/n 002248 ©2005 HydroCAD Software Solutions LLC 5/25/2005 Subcatchment A-112: SUBCATCH A-1 1A-2 Hydrograph ®Runoff 4 3.90 ds Type III 24-hr 100 year Rainfall=6.40" 3 Runoff-Area=67,301 sf- Runoff Volume=13,798 cf Runoff Depth=2.46° 2 Flew Len- h=406 LL Tc=9 1 min CN=63 1 0 2 4 6 8 10 12 14 16 18 20 22 24 26 28 30 32 34 36 38 40 42 44 46 48 Time (hours) 249 MARBLERIDGE ROAD, NORTH ANDOVER POST Type 11124-hr 100 year Rainfall=6.40" Prepared by NEW ENGLAND ENGINEERING SERVICES INC. Page 50 HydroCADO 7.10 s/n 002248 C 2005 HydroCAD Software Solutions LLC 5/25/2005 Subcatchment R-1: ROOF LOT 1 Runoff = 0.36 cfs @ 12.06 hrs, Volume= 1,185 cf, Depth= 6.16" Runoff by SCS TR-20 method, UH=SCS, Time Span= 0.00-48.00 hrs, dt=0.01 hrs Type III 24-hr 100 year Rainfall=6.40" Area (sf) CN Description 2,307 98 Paved parking & roofs Tc Length Slope Velocity Capacity Description (min) (feet) (ft/ft) (ft/sec) (cfs) 0.5 40 0.0250 1.3 Sheet Flow,ROOF Smooth surfaces n= 0.011 P2= 3.20" 3.6 215 0.0200 1.0 0.00 Circular Channel (pipe), PIPE TO INFILTRATOR Diam= 0.5" Area= 0.0 sf Perim= 0.1' r= 0.01' n=0.010 PVC, smooth interior 4.1 255 Total Subcatchment R-1: ROOF LOT 1 Hydrograph 0.38 ®Runoff - 0.36 0.34z Type III;24 ter=104 year = 0.32 _ Rainfall=6.40'-' - 0.3 -- -' - 0.26 - - - 307-sf- ' - - Runoff Area- 2, 024 - Runoff Volume= a1 5= - fi 0.22 - - 0.2 -Runoff Depth=6.16"-- 3 LL o.,s -- - - FIoW Length-255'-- 0.16 - - -- -. - 0.14 _ - - Tc=4.1 min 0.12 -- CN=98 _ 0., 0.08- - 0.0s - 0.04'" - 0.02 ' 0 0 2 4 6 8 10 12 14 16 18 20 22 24 26 28 30 32 34 36 38 40 42 44 46 48 Time (hours) 249 MARBLERIDGE ROAD, NORTH ANDOVER POST Type 111 24-hr 100 year Rainfall=6.40" Prepared by NEW ENGLAND ENGINEERING SERVICES INC. Page 51 HydroCADS 7.10 s/n 002248 ©2005 HydroCAD Software Solutions LLC 5/25/2005 Subcatchment R-2: ROOF LOT 2 Runoff = 0.26 cfs @ 12.06 hrs, Volume= 874 of, Depth= 6.16" Runoff by SCS TR-20 method, UH=SCS, Time Span= 0.00-48.00 hrs, dt= 0.01 hrs Type III 24-hr 100 year Rainfall=6.40" Area (sf) CN Description 1,703 98 Paved parking &roofs Tc Length Slope Velocity Capacity Description (min) (feet) (ft/ft) (ft/sec) (cfs) 0.2 40 0.2500 3.1 Sheet Flow, ROOF Smooth surfaces n= 0.011 P2= 3.20" 3.9 165 0.0100 0.7 0.00 Circular Channel (pipe), PIPE TO INFILTRATOR Diam= 0.5" Area= 0.0 sf Perim=0.1' r-0.01' n=0.010 PVC, smooth interior 4.1 205 Total Subcatchment R-2: ROOF LOT 2 Hydrograph 0.28 0.26- T e-111-24-hr-100.year- 0.24' - _ yp - 0.22 - -- -Rainf aU=6.40°ff - Runo -- 0.2 - - . Area=1,703 sf 018 Runoff volume=&74 tf-- 0.16 0 0.14: - - Runoff-Depth=6.167 - 0.12 Flow .Length=205'-0.1- Tc=4.-1 min - 0.0a 0.06 7CN=98-- 0.04 0.02 0 0 2 4 6 8 10 12 14 16 18 20 22 24 26 28 30 32 34 36 38 40 42 44 46 48 Time (hours) 249 MARBLERIDGE ROAD, NORTH ANDOVER POST Type /I/24-hr 100 year Rainfall=6.40" Prepared by NEW ENGLAND ENGINEERING SERVICES INC. Page 52 HydroCAD®7.10 s/n 002248 ©2005 HydroCAD Software Solutions LLC 5/25/2005 Pond 1 P: SUMMATION POND Inflow Area = 67,301 sf, Inflow Depth = 2.46" for 100 year event Inflow = 3.90 cfs @ 12.13 hrs, Volume= 13,798 cf Outflow = 3.90 cfs @ 12.13 hrs, Volume= 13,798 cf, Atten= 0%, Lag= 0.0 min Primary = 3.90 cfs @ 12.13 hrs, Volume= 13,798 cf Routing by Stor-Ind method, Time Span= 0.00-48.00 hrs, dt=0.01 hrs Peak Elev= 0.01' @ 12.13 hrs Surf.Area= 0 sf Storage= 0 cf Plug-Flow detention time= 0.0 min calculated for 13,795 cf(100% of inflow) Center-of-Mass det. time= 0.0 min ( 854.3-854.3) Volume Invert Avail.Storage Storage Description #1 0.00' 1 cf Custom Stage Data Listed below Elevation Inc.Store Cum.Store (feet) (cubic-feet) (cubic-feet) 0.00 0 0 10.00 1 1 Device Routing Invert Outlet Devices #1 Primary 0.00' 999.0' long x 9.0' breadth Broad-Crested Rectangular Weir Head (feet) 0.20 0.40 0.60 0.80 1.00 1.20 1.40 1.60 1.80 2.00 2.50 3.00 3.50 4.00 4.50 5.00 5.50 Coef. (English) 2.46 2.55 2.70 2.69 2.68 2.68 2.67 2.64 2.64 2.64 2.65 2.64 2.65 2.65 2.66 2.67 2.69 Primary OutFlow Max=0.87 cfs @ 12.13 hrs HW=0.01' (Free Discharge) 'L1=13road-Crested Rectangular Weir (Weir Controls 0.87 cfs @ 0.2 fps) 249 MARBLERIDGE ROAD, NORTH ANDOVER POST Type 11124-hr 100 year Rainfall=6.40" Prepared by NEW ENGLAND ENGINEERING SERVICES INC. Page 54 HydroCADO 7.10 s/n 002248 ©2005 H&oCAD Software Solutions LLC 5/25/2005 Pond 1-1: INFILTRATOR LOT 1 Inflow Area= 2,307 sf, Inflow Depth = 6.16" for 100 year event Inflow = 0.36 cfs @ 12.06 hrs, Volume= 1,185 cf Outflow = 0.00 cfs @ 0.00 hrs, Volume= 0 cf, Atten= 100%, Lag= 0.0 min Primary = 0.00 cfs @ 0.00 hrs, Volume= 0 cf Routing by Stor-Ind method, Time Span= 0.00-48.00 hrs, dt= 0.01 hrs Peak Elev= 102.22' @ 24.25 hrs Surf.Area=661 sf Storage= 1,185 cf Plug-Flow detention time= (not calculated: initial storage excedes outflow) Center-of-Mass det. time= (not calculated: no outflow) Volume Invert Avaii.Storage Storage Description #1 99.00' 460 cf Custom Stage Data(Prismatic) Listed below 2,314 cf Overall-781 cf Embedded = 1,533 cf x 30.0%Voids #2 99.50' 781 cf 44.6"W x 30.0"H x 30.26%StormTech SC-740 x 4 Inside#1 1,241 cf Total Available Storage Elevation Surf.Area Inc.Store Cum.Store (feet) (sq-ft) (cubic-feet) (cubic-feet) 99.00 661 0 0 102.50 661 2,314 2,314 Device Routing Invert Outlet Devices #1 Primary 102.50' 0.5" x 45.0' long Culvert CPP, projecting, no headwall, Ke=0.900 Outlet Invert= 98.00' S= 0.1000'P Cc= 0.900 n=0.010 PVC, smooth interior Primary OutFlow Max=0.00 cfs @ 0.00 hrs HW=99.00' (Free Discharge) t--1=Culvert (Controls 0.00 cfs) 249 MARBLERIDGE ROAD, NORTH ANDOVER POST Type 11124-hr 100 year Rainfall=6.40" Prepared by NEW ENGLAND ENGINEERING SERVICES INC. Page 55 H droCAD®7.10 s/n 002248 ©2005 H droCAD Software Solutions LLC 5/25/2005 Pond 1-1: INFILTRATOR LOT 1 Hydrograph ®Inflow 0.38 0s6ds 1 i ®Primary 0.36 0.34 _ Inflow Ar"ea=2,307 sf 0.32 - -Peak-EleV=102.22' 0.3 - - - - 0.26 0.26 -Sfo-rake=1,1-85_c f- 0.24 -_ Q.5'_ x 45.0' Culvert - 0.22 0.2 0.16 - 0.16 0.14 0.12 0.1 0.08: 0.06 0.04 0. oaoa_c 0 0 2 4 6 8 10 12 14 16 18 20 22 24 26 28 30 32 34 36 38 40 42 44 46 48 Time (hours) 249 MARBLERIDGE ROAD, NORTH ANDOVER POST Type 11124-hr 100 year Rainfall=6.40" Prepared by NEW ENGLAND ENGINEERING SERVICES INC. Page 57 HydroCAD®7.10 s/n 002248 ©2005_HydroCAD Software Solutions LLC 5/25/2005 Pond 1-2: INFILTRATOR LOT 2 Hydrograph - . ®Inflow 0.28 0.26 c ®Primary 0.26 Inflow Area=1 J03 sf- 024 Peak-Elev=99,04' 022 - 0.2 - Storage-=874 cf 0:5" x40.0` Culvert - 0.16 - c 014 -- - - - u. 0.12 , 0.1 - - - 0.08 0.06 0.04-' -- 0. ?©oti ds= 0 0 2 4 6 8 10 12 14 16 18 20 22 24 26 28 30 32 34 36 38 40 42 44 46 48 Time (hours) SUMMARY The following tables summarize the pre development vs.post development runoff flow for the 2, 10,and 100 year storms. Due to the proposed construction of the infiltration facilities the Post Development flow rates and volumes are lower than the Pre Development flow rates and volumes. Because the flow rates and volumes are reduced, no down stream properties will be adversely affected by this project. In the summary table below the pre development flows for both subcatchments are combined. The calculations were done using two drainage subcatchments to demonstrate the rate and volume of flow which drained on to the neighboring property. The flow from both subcatchments eventually ends up in the wetland behind the neighbors property. The post development flow path will be change to avoid any water from the project site flowing on to the neighbors property by directing the flow that previously flowed over the neighbors property away from their front yard to the rear yard of the project site. This in essence combines the two pre development subcatchments in to one,however the ultimate path of the water is still the same. PRE VS.POST DEVELOPMENT DRAINAGE FLOW SUMMARY TABLE Design Pre Dev. Post Dev. Change Storm (cfs) (cfs) (cfs) 2 0.75 0.13 (0.62) 10 2.21 1.86 (0.35) 100 4.51 3.90 (0.61) 58 Table 2-2a.—Runoff curve numbers for urban areas[ Curve numbers for Cover description hydrologic soil group— Average percent Cover type and hydrologic condition impervious areal A B C D Fully developed urban areas (vegetation established) Open space (lawns, parks, golf courses, cemeteries, ete.)3: Poor condition (grass cover < 50%) .............. 68 79 86 89 Fair condition(grass cover 50% to 75%)........... 49 69 79 84 Good condition(grass cover > 75%) .............. 39 61. 74 80 Impervious areas: Paved parking lots, roofs, driveways, etc. (excluding right-of-way). ......................... 98 98 98 98 Streets and roads: Paved; curbs and storm sewers(excluding right-of-way).................................. 98 98 98 98 Paved; open ditches(including right-of-way) ....... 83 89 92 93 Gravel(including right-of-way) ................... 76-. 85 89, 91 Dirt(including right-of-way) ..................... 72 82 87 89 Western desert urban areas: ., Natural desert landscaping(pervious areas only)4... 63 77 85 88 Artificial desert landscaping(impervious weed barrier, desert shrub with 1- to 2-inch sand or gravel mulch and basin borders). .............. 96 96 96 96 Urban districts: Commercial and business.......................... 85 89 92 94 95 Industrial........................................ 72 81 88 91 93 Residential districts by average lot size: 118 acre or less(town houses)...................... 65 77 85 90 92 114 acre ......................................... 38 61 75 83 87 1/3 acre ......................................... 30 57 72 81 86 112 acre ......................................... 25 54 70 80 85 1 acre ........................................... 20 51 68 79 84 2 acres .......................................... 12 46 65 77 82 Developing urban areas Newly graded areas (pervious areas only, no vegetation)5................................... 77 86 91 94 Idle lands (CN's are determined using cover types - similar to those in table 2-20. 'Average runoff condition, and 1,, =0.2S. ZThe average percent impervious area shown was used to develop the composite CN's.Other assumptions are as follows: impervious at are directly connected to the drainage system, impervious areas have a CN of 98,and pervious areas are considered equivalent to open space in good hydrologic condition.CN's for other combinations of conditions may be computed using figure 2-3 or 24. 'CN's shown are equivalent to those of pasture.Composite CN's may be computed for other combinations of open space cover type. "Composite CN's for natural desert landscaping should be computed using figures 2-3 or 24 based on the impervious area percentage =98)and the pervious area CN.The pervious area CN's are assumed equivalent to desert shrub in poor hydrologic condition. - "Composite CN's to use for the design of temporary measures during grading and construction should be computed using figure 2-3 or based on the degree of development(impervious area percentage)and the CN's for the newly graded pervious areas. (0O (210-VI-TR-55, Second Ed., June 1986) C Table 2-2h.—Runoff curve numbers for cultivated agricultural lands, Curve numbers for Cover description Curve soil group— Hydrologic Cover type TreatmentL condition3 A B C D Fallow Bare soil — 77 86 91 94 Crop residue cover(CR) Poor 76 85 90 93 Good 74 83 88 90 Row crops Straight row(SR) Poor 72 81 88 91 Good 67 78 85 89 SR + CR Poor 71 80 87 90 Good 64 75 82 85 Contoured(C) Poor 70 79 84 88 Good 65 75 82 86 C + CR Poor 69 78 83 87 Good 64 74 81 85 Contoured & terraced(C&T) Poor 66 74 80 82 Good 62 71 78 81 C&T + CR Poor 65 73 79 81 Good 61 70 77 80 Small grain SR Poor 65 76 84 88 Good 63 75 83 87 SR + CR Poor 64 75 83 86 Good 60 72 80 84 C Poor 63 74 82 85 Good 61 73 81 84 C + CR Poor 62 73 81 84 Good 60 72 80 $3 C&T Poor 61 72 79 82 Good 59 70 78 81 C&T + CR Poor 60 71 78 81 Good 58 69 77 80 Close-seeded SR Poor 66 77 85 89 or broadcast Good 58 72 81 85 legumes or C rotation Poor 64 75 83 85 meadow Good 55 69 78 83 C&T Poor 63 73 80 83 Good 51 67 76 80 'Average runoff condition,and I;, =025. 1 Crop residue corer applies only if residue is on at least 514 of the surface throughout the,year. :,Hydrologic condition is based on combination of factors that affect infiltration and runoff, including(a)density and canopy of vegetative u eet ,(U)amount of year•►ound cover,(c)amount of grasr or(!lose--;seeded legumes in rotations,(d)percent of residue cover on the laid sur- face(good >_ '20%),and(e)degree of surface roughness. Coon. Factors impair infiltration and tend to increase runoff. Good. (''actors encourage average and better than average infiltration and tend to decrease runoff. 2-6 (210-VI-TR-55_ Seennrl Pal _Tilm, 14Rm Table 2-2c.—Runoff curve numbers for other agricultural lands' Curve numbers for Cover description hydrologic soil group— Hydrologic Cover type condition A B C D Pasture, grassland, or range—continuous Poor 68 79 86 89 forage for grazing.2 Fair 49 69 79 84 Good 39 61 74 80 Meadow—continuous grass, protected from — 30 58 71 78 grazing and generally mowed for hay. Brush—brush-weed-grass mixture with brush Poor 48 67 77 83 the major element' Fair 35 56 70 77 Good 430 48 65 73 Woods—grass combination(orchard Poor 57 73 82 86 or tree farm)5 - Fair 43 65 76 82 Good 32 58 72 79 Woods.6 Poor 45 66 77 83 1 Fair 36 60 73 79 Good 430 55 70 77 Farmsteads—buildings, lanes, driveways, — 59 74 82 86 and surrounding lots. 'Average runoff condition.and 1;, = o.2S. 2j'ricn•: <5W ground cover or heavily grazed with no mulch. Fair: 50 to 75% ground cover and not heavily grazed. G awl: >75ck ground cover and lightly or only occasionally grazed. 111(mir. <50%.ground cover. F(dr: 50 to 75% ground cover. Gcxxl: >75% ground cover. 'Actual curve number is less than 30;use CN = 30 for runoff computations. 'CN's shown were computed for areas with 5N woods and 5W grass(pasture)cover.Other combinations of conditions may be compu from the CN's for woods and pasture. 'Poor: Forest litter.small trees, and brush are destroyed by heavy grazin or regular burring. Fair: Woods are grazed but not burned, and some forest litter covets the soil. (kmd: Woods are protected from grazing,and litter and brush adequately cover the soil. !v oZ (210-VI-TR-55, Second Ed., June 1986) Table 2-2d.—Runoff curve numbers for arid and semiarid rangelands' Curve numbers for Cover description hydrologic soil group— Cover type Hydrologic 2 condition A3 B C D Herbaceous—mixture of grass, weeds, and Poor low-growing brush, with brush the 80 87 93 minor element. Fair 71 81 89 Good 62 74 85 Oak-aspen—mountain brush mixture of oak brush, Poor aspen, mountain mahogany, bitter brush, maple, 66 74 79 and other brush. Fair 48 57 63 Good 30 41 48 Pinyon-juniper—pinyon,juniper, or both; Poor grass understory. 75 85 89 Fair 58 73 80 Good 41 61 71 Sagebrush with grass understory. Poor 67 80 85 Fair 51 63 70 Good 35 47 55 Desert shrub—major plants include saltbush, Poor 63 77 85 greasewood, creosotebush, blackbrush, bursage, 88 Fair 55 72 81 86 palo verde, mesquite, and cactus. Good 49 68 79 84 'Average runoff condition,and 1;, =0.2S. For range in humid regions, use table 2-2c. -l'uor: <:3O</ grvwid cover(litter,grates,and brush overstory). h'nir: :30 to 76% ground cover. Goad: >70% ground cover. 'Curve numbers for group A have been developed only for dessert shrub. �3 - 2-8 (210-VI-TR-55, Second Ed., June 1986) ESSEX COUNTY, MASSACHUSETTS, NORTHERN PART — (Joins sheet 23) PcE Z p 125 �t P St8 PaE3 ,PaD PaD n PbD. StC L F g r PaB PaD PaC t CrC 1 3: )d; Raq wsB j; F _ _ Z Wr6;- Cm6 ' Pa8 RdA R18 Ur \WeA Wr6 n <s leA wet¢ Oe Cde Pb8 _ e Pa8 . PaB$e 6 Wh PaB. }� £' W n �i 1 CaB W rB �' UD S\ Ws6 P $ m . C< NORTH PaB "wtc. �,� suc ANDOVER n' �a PbD_ PbES r F coc O �ti # f r 6p StA b €F� r 4 c stc S1� t)f ��`. ' `•:`,(��•• tmp � - c S 3«Y �G� { r'y.y'� �� �L, .SUB - r Wr8 { i StAY j c PaC SPi Ws c CaD 3 z UD s a._ �p -PbD � pdtTt�,�, WeA % , ` ;_ Pa6 StB T{ 3 Wti F l Ca, Se . 5uB s X01 O 6 rJ M C : t Sod St8 ,t B Wrq r s U d r fee St6 8r6 Cr 6 CSC ' ft W rA. • \ RdA D pace Wg O MmB .' 'c 3 •�'y °B Mp Wt� Id A PaD bf, CoB s0 Cb.0 P4D - � -' Pa6 Wr6 S IEG °Q P WsC \ Se dB StA Wg arc r8 PaC PaB WrC PaC� i33 W rA r PaD m 1 RIB C1TD ;: U - Sd8 RdA �Ftl6 (WTI,VJg\ WrA cw Cbf` CbC Wh\ \ Pa8 o Sh8/ Q�e PaB Rae` Wh S\u6 Pf�D SgC SUE ° CbC `t!y U Od cE MINis NrA y RdA PPaB Hill gg8 RIB Oa C4E3`; u° p r \\ SrB \ \ �Lr RdA RdA 114 Wg w SUB \ ` }25 aP P,D ShC RIB N ` ShE3 CbC Si 000 FEET /Inins<h—t IM r It 94 SOIL SURVEY (2.5Y 5/4) ped interior; varved silt and clay with very B22-22 to 26 inches; light olive brown (2.5Y 5/4) grav- thin strata of very fine sand between varves; overall -elly fine sandy loam; few fine faint grayish brown texture of silty clay; strong coarse and very coarse (2.5Y 5/2) mottles; and few fine distinct yellowish prismatic structure; very firm, sticky, plastic; clay brown (10YR 5/6) mottles; weak fine granular struc- films on prism faces and in pores; slightly acid. ture; friable; 15 percent angular gravel, 10 percent angular cobblestones; very strongly acid; clear wavy The thickness of the silty layer over the contrasting boundary. clayey material is 18 to 40 inches. The profile is typically C1-26 to 31 inches; light olive brown (2.5Y 5/4) gravel- free of coarse fragments, but some pedons contain a ly fine sandy loam; common fine and medium dis- few granite or quartzite pebbles. Reaction in the upper tinct gray (N 5/0) and strong brown (7.5YR 5/6) part of the solum ranges from strongly acid to slightly mottles; massive; friable; 25 percent angular gravel, acid. In some places the surface layer is neutral if heav- 10 percent angular cobblestones; very strongly acid; ily limed. The lower part of the solum and the substratum abrupt wavy boundary. are medium acid to neutral. C2-31 to 60 inches; light olive gray (5Y 6/2) gravelly The Ap horizon has hue of 10YR, value of 3 or 4, and fine sandy loam; many fine and medium prominent chroma of 2 or 3. light gray (N 7/0), yellowish brown (10YR 5/6), dark The B21 horizon has hue of 10YR or 2.5Y, value of 4 reddish brown (5YR 3/4), and yellowish red (5YR or 5, and chroma of 4 to 6. The B22 and B23 horizons 5/8) mottles; massive; friable; 10 percent angular have hue of 2.5Y or 5Y, value of 4 or 5, and chroma of 2 gravel, 10 percent angular cobblestones; very to 4. Clay films are common in some pores. Some ped strongly acid. faces have patchy clay films on the top and on vertical faces. The thickness of the solum ranges from 20 to 30 The IIC horizon has hue of 2.5Y or 5Y, value of 4 to 6, inches. The depth to mottling ranges from 16 to 24 and chroma of 2 to 4. It is silty clay loam or silty clay. In inches. Gravel-size coarse fragments make up 5 to 25 the upper part of this horizon, clay flows are common in percent of the solum. Reaction in unlimed areas is very pores and on ped faces. Patchy or discontinuous black strongly acid to medium acid. coatings are common on the ped faces. The A horizon has hue of 7.5YR or 10YR and value and chroma of 2 to 4. It is fine sandy loam, very fine sandy loam, or loam. SUttOrl Serl @S The B21 horizon has hue of 7.5YR or 10YR, value of 4 The Sutton series consists of coarse-loamy, mixed, or 5, and chroma of 4 to 6. It is fine sandy loam, sandy mesic A uic loam, or loam. The B22 horizon has hue of 10YR to 5Y, q Dystrochrepts. These deep, moderately well value of 4 or 5, and chroma of 4 to 6 and is distinctly or drained soils are on uplands. The soils formed in glacial prominently mottled. It is fine sandy loam or sandy loam. till. Slopes range from 0 to 15 percent. The C horizon has hue of 2.5Y or 5Y, value of 5 or 6, Sutton soils formed in the same kind of material as and chroma of 2 to 4. It is fine sandy loam, sandy loam, well drained Charlton soils, poorly drained Leicester or gravelly analogues of these textures. The consistence soils, and very poorly drained Whitman soils. They are in the C horizon ranges from friable to firm. The horizon similar to the Scituate and Woodbridge soils. Sutton soils is massive or has platy structure. do not have a fragipan, which the Scituate and Wood- bridge soils have. They have less sand in the substratum than the Scituate soils. Swanton Series Typical pedon of Sutton fine sandy loam, 3 to 8 per- The Swanton series consists of coarse-loamy over cent slopes, in.the town of Boxford, 600 feet west of the clayey, mixed, nonacid mesic Aeric Haplaquepts. These junction of Interstate Route 95 and Massachusetts Route deep, poorly drained soils are on lacustrine and marine 97: plains. The soils formed in glacial outwash over lacus- Ap-0 to 9 inches; very dark grayish brown (10YR 3/2) trine or marine sediments. Slopes range from 0 to 8 fine sandy loam; weak fine granular structure; fri- percent.Swanton soils formed in the same kind of material as able; many fine roots; 10 percent angular gravel, 5 moderately well drained Elmwood soils, well drained Mel- percent angular cobblestones; strongly acid; abrupt rose soils, and very poorly drained Whately Variant soils. smooth boundary. They are similar to Raynham, Scantic, and Walpole Vari- B21-9 to 22 inches; yellowish brown (10YR 5/4) fine ant soils. Swanton soils have more clay in the substra- sandy loam; weak fine granular structure; friable; tum than the Raynham soils, have more sand and less common fine roots; 10 percent angular gravel, 5 silt in the solum than the Scantic soils, and have a percent angular cobblestones; very strongly acid; substratum that has more clay and less stratification clear smooth boundary. than that in the Walpole Variant soils. SOIL SURVEY 192 TABLE 16.--SOIL AND WATER FEATURES--Continued ,_ Flooding , High water table , ,_Risk of corrosion Soil name and ;Hydro-1 , It , , , ;Potential; , map symbol 1 logic! Frequency 1 Duration !Months 1 Depth- 1 Kind !Months 1 frost !Uncoated !Concrete !group ! ! ! ! ! ! ! action 1 steel 1 Ft ! ! ! ! v ! ! ! RnC*, RnD*: Rock outcrop. Buxton-----------1 C !None--------1 --- 1 --- 11.0-3.01Perched l Nov-May!High-----!High-----!Moderate. RoC*, RoD*: ! , Rock outcrop. ! Charlton---------1 B !None--------! --- ! --- 1 >6.0 1 --- I --- !Low------!Low------!High. Hollis-----------1 C/D !None--------! --- ! --- ! >6.0 1 --- I --- !Moderate !Low------!High. Rx*: I I ! ! ! ! ! ! Rock outcrop. I I 1 It , 1 1 1 1 , Hollis-----------1 C/D !None--------! -- ! --- 1 >6.0 1 --- 1 --- ;Moderate ;Low------;High. ! ! ! It ! I Sa----------------1 C !Frequent----!Brief-----!Nov-May! 0-1.0!ApparentI Nov-Jun!High-----!High-----!Moderate. Saco Variant I I ! ! ! ! ! ! ! ! I ! ! ! ! I I I ! I ScA, ScB----------1 C !None--------1 --- ! --- 1 0-1.01Perched l Oct-JunlHigh-----!High-----!Moderate. Scantic ! ! ! ! ! ! ! ! ! ! Se----------------I D !Rare--------'1 --- 'I --- �1 0-1.0lApparentlJan-DeclHigh-----(Moderate (High. Scarboro SgB, SgC, ShB, ! ! ! ! ! ! ! ! ! ShC--------------1 C (None--------1 --- ! --- 11.0-3.01Perched IDec-AprIHigh-----(Moderate (High. Scituate ! It ! ! I I It It It , ! It It ! It It It It It Sr A, SrB----------1 1B !None--------I --- ! --- 11.0-3.0!Apparent!Dec-AprlModerate ILow------!High. Sudbury ! ! ! ! i I SsB, SsC----------1 C !None--------1 --- ! --- ! >6.0 1 --- ! --- IHigh-----!Moderate !Moderate. Suffield StA, StB, StC, ! ! ! ! ! ! ! ! ! ! SuB, SuC---------1 B !None--------! --- ! --- 11.5-3.5!Apparent',Nov-Apr!Moderate !Low------!High. Sutton ! ! ! ! ! ! ! ! I 0-1.5lApparentIHov-MaylHigh-----!High-----!Moderate.SNA, SwB----------! B/D None--------! Swanton ! ! ! ! ! ! ! ! ! ! , UAC*. ! ! ! ! ! ! ! ! ! ! Udipsamments ! , UD* ! ! ! ! ! ! ! ! ! ! Udorthents ! ! ! ! ! ! ! ! ! ! UnA, UnB, UnC-----1 B (None to rare! --- ! --- ! >6.0 ! --- ! --- !Moderate !Low------(Moderate. Unadilla I I ! ! ! ! ! It ' ' Ur* ! ! ! ! 1 ! - ! I ! ! Urban land ! ! ! ! ! ! ! , WaA, WaB----------1 C !None--------! --- ! --- ! 0-1.0lApparentl Nov-Apr!High-----!Low------!High. Walpole I ! ! ! ! ! ! ! ! ! Wb----------------1 C !None--------I --- ! --- ! 0-1.0lApparent�INov-JunlHigh-----!High-----(High. Walpole Variant I ! ! ! ! ! ! 1 1 , , WeA, WeB----------1 C !None--------1 --- 1 --- 1 0-1 .5lApparentlSep-JunlModerate !Moderate !High. Wareham 1 I ! ! ! ! ! ! ! I Wf----------------I C !None--------1 --- I --- I 0-1.0lApparent�I Nov-JunlHigh-----!High-----!Moderate. Whately Variant 1 1 ! I ! I ! I ' ' I I See footnote at end of table. Figure 2 = Frec:initation Values for ".assachusetts 2.8" 3.OI1 ESSEX FRANKLIN 11 MIOOLESEX SUFFOLK r « HANNPfNtRCC ORCESTER r W POEN NoFf° � 3. 3.6 IPA O RAINFALL DATA MAP 2-YEAR,24 HOUR PRECIPITATION (INCHES) / d� NANTUCKET TP-40 ESSEX FRANKLIN WORCESTER MIOOLEIEX SNFFO�K NANtt►>t*ONE 4.0 W O a, 4.21t NA 0 4.4" 4 G� .p Z O RAINFALL DATA MAP �ARNfT 4. 5—YEAR,24—HOWL PRECIPITATION (INCHES) NANTUCKET i A ; TP-40 -�.a.t (210-FFM, Arend. MA1 , Anril 1990) PIA 2-2� ti7. Figure 2 - Precipitation Values for Iassachusetts 4.211 4.5 4.411 4.3 ESSEX 4.6" FRANKLIN MIDDLESEX SUFFOLK = HAMPSHIRE WORCESTER �11 h Y 4 O4- HAMPDEN OG p 4.8'1 NJ. O RAINFALL DATA MAP BARNSTAB c 10-YEAR,24 HOUR PRECIPITATION (INCHES) oa 4 911 KE5 NANTUCKET t. TP-40 5.311 5.0" 5.l'1 5.2t1 5.411 ESSEX FRANKLIN 5.511 MIDDLE EX SUFFOLK = WORCESTER Y HAMPSHIRE ''.... W 0.1* 5.6" NAMPOEN Ci ® 5.7" pia i 0 BARNS k RAINFALL DATA MAP 5.8" 25-YEAR,24-HOUR PRECIPITATION (INCHES) C" OU b NANTUCKL TP-40 * 2-22 (2) (2 10 T..enCL Pr)ri1 1990 Fiaure 2 - Precipitation Values for *lassachusetts 5.811 5.611 5.7R rJ 9R ESS[x FRANKLIN 6.0 11 41OOLESEX SUFFOLK 6.111 H NAIIPSIINIE WORCESTER Y W MAYPOEN 0 6.311 a s u C RAINFALL DATA MAP SARNSTA 6.4' 50—YEAR,24 HOUR PRECIPITATION (INCHES) 40 dd 6.5u OUK 14ANTUCKET TP-40 6.0" 6 6.411 sux f RAN1�Y1 6.6" Q 111001ESEx = ORCESTER 3UAOl1 I p 4 NAtlPMI/� 6.8 N W O NAYPO[N �� �A 7 " 0 RAINFALL DATA MAP 7.2" 100—YEAR,24—HOUR PRECIPITATION (INCHES) RANTYCKLT TP-40 (210-M, �rmnd. ._�1, A*)ri1 1990) :211, 2-22