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Storm ReportSTORMWATER MANAGEMENT REPORT and STORMWATER POLLUTION PREVENTION PLAN NARATIVE for GARVEY KIA Quaker Road Queensbury, NY Prepared by: NACE ENGINEERING, P.C. 169 HAVILAND ROAD QUEENSBURY, NY 12804 Thomas W. Nace, P.E. April 15, 2015 File: #47561 STORMWATER MANAGEMENT REPORT GARVEY KIA Quaker Road Queensbury. NY Site Location The project site is a portion of an existing 20 acre parcel located on the northeast side of Quaker Road, east of Ridge Road and just north of the Garvey Volkswagen dealership. The parcel is bordered on the south by Quaker Road and on the west, north and east by the wetlands adjacent to the south end of the Warren County Airport. This report addresses drainage issues pertaining to the construction of a new auto dealership building and associated sitework on approximately 7.5 acres. Existing Conditions The existing property is vacant woodland. A section of wetland runs northeast — southwest through the center of the parcel dividing the parcel into two upland sections. The proposed development will be on the eastern section of upland. The USDA Soil Survey of Warren County shows the soils in the area to be developed as Belgrade silt loam, Farmington loam, Madalin silt loam and Rhinebeck silt loam. These are generally silty, tight soils underlain by clay, and have a high seasonal water table. Test pits on the project site confirmed the soils to be silty loams underlain by clays. Mottling was generally around 1 to 2 feet. The existing site has a high ridge running northeast from Quaker Road. The land slopes down 8 to 12 feet from this ridge to the wetland areas to the east and west of the site. Runoff from the site generally drains to the northwest and to the southeast, into the wetlands. Existing Conditions Summary: Parcel Area: Building & Pavement Coverage Pervious Surface: 20.00 acres 0.00 acres = 0% 20.00 acres = 100% Proposed Development The proposed project consists of development of a 20 acre lot with a 18,050 square foot auto dealership building and associated site work. The proposed project will result in the following lot coverage: Proposed Conditions Summary Parcel Area: 20.00 acres Building Coverage 0.41 acres = 2.0% Pavement Coverage: 3.17 acres = 15.9% Pervious Surface: 16.42 acres = 82.1 % The proposed development will result in an increase of impervious surface of 17.9% 1 Construction Phasing The project will be constructed in a single phase. Green Infrastructure Practices and Requirements As stated in the New York State Stormwater Management Design Manual, Section 3.2 — Green Infrastructure for Stormwater Management "The objective is to replicate pre -development hydrology by maintaining pre -construction infiltration, peak runoff flow, discharge volume, as well as minimizing concentrated flow by using runoff control techniques to provide treatment in a distributed manner before runoff reaches the collection system". Due to the silty nature of the existing site soil, there is little opportunity to use infiltration practices. However, there will be a shallow dry swale around the perimeter of the site which will collect all of the sheet runoff from the hard surfaces. This swale will retain a foot of water which will be allowed to slowly infiltrate into the silty loam soils. Specific Green Infrastructure Practice goals are being addressed as follows: Planning Practices for Preservation of Natural Features and Conservation Preservation of undisturbed areas - This project is located in a commercial area which is substantially developed. However, due to the presence of existing wetland a substantial natural buffer across the north, east and west sides of the site will remain undisturbed. Reduction of clearing and grading — parking and site circulation roads kept to a minimum. However, this is an auto dealership which requires large paved areas for auto display. Locating development in less sensitive areas — all planned development has been located in the upland areas of the site, retaining natural buffers around the perimeter. Open space design — as previously stated, wide perimeter wetland buffers are being maintained. Soil restoration — Existing soil on the site is not very permeable. Soil restoration / modification will be required in the areas under the vegetated swales to achieve some degree of permeability Planning Practices for Reduction of Impervious Cover Roadway reduction — roadway length has been kept to a minimum required to access the site. Sidewalk reduction — Sidewalk length has been kept to a minimum required for access. Driveway reduction — Driveway length has been dictated by the necessity for truck and emergency vehicle access to the building. Building footprint reduction — nature of project is not conducive to multi -story building. Parking reduction — parking dictated by proposed use as an auto dealershsip. 2 Green Infrastructure Techniques Rain Gardens — mainly used for residential development, rain gardens are generally not appropriate for larger commercial or industrial projects. Green Roofs — Green roofs are very expensive to construct and maintain. Additionally, they are only marginally suitable for cold climates. They were not considered for this project because better alternatives were available. Stormwater Planters — Generally used for small areas of pavement, stormwater planters were not considered for this project due to the size of the hard surfaces to be accommodated. Rain Barrels — Like stormwater planters, rain barrels are generally used for small roof areas unless there is a great need for the collected water. Additionally, they are generally unsuitable for cold climates. Porous Pavement — On this project, porous pavement would only be considered appropriate due to the impermeable nature of the site soils. Proposed Stormwater Management All runoff from developed portions of the site will be handled by shallow vegetated swales and stormwater pocket ponds. Runoff will sheet flow off the edges of the paved area into gravel diaphragms which will collect sediment and act as level spreaders feeding runoff into shallow dry swales surrounding the site. The shallow swales will be 11/z feet deep with a level bottom. The swales will temporarily store and pretreat runoff in the bottom foot and will outlet excess flow over a rip -rap outlet channel into one of two pocket ponds. The dry swales will serve as a runoff -reduction feature to meet the requirements of NYSDEC Stormwater Management for minimum RRv. The two pocket ponds will be located at the southeast corner of the site and along the northwest side of the site. Each pond will have a fore bay for pretreatment and a staged outlet structure to control peak runoff to predevelopment conditions. Calculations For analysis purposes the project is broken into two stormwater management areas: - East and south side of site (1/2 roof, parking lot) - West and north sides of site (1/2 roof, parking lot) Stormwater Management Worksheets for each of these stormwater management areas (SMA) are included in the appendices. These provide the calculations for Water Quality Volume (WQv), minimum Runoff Reduction Volume (RRv) required, and RRv provided. These calculations are summarized as follows: Kj Water Quality Control The Water Quality Volume (WQv) as defined by P x Rv x A / 12 represents the anticipated runoff from the developed site during a 90% rainfall event. In accordance with the New York State Stormwater Management Design Manual, the WQv must be treated either through green infrastructure practices or through standard WQv treatment practices such as ponds and wetlands. The following table summarizes the required WQv and the provided WQv for each stormwater management area as derived in the Stormwater Management Worksheets in the appendices. (note that the WQv required is equal to the WQv provided because all runoff from the 90% storm -1" rainfall — is being infiltrated in the proposed infiltration facilities) Stormwater Management Area Southeast Northwest Runoff Reduction Re uired W v WQv Required (cf) WQv Provided 1,359 19,872 8,020 14,844 The New York State Stormwater Management Design Manual requires that Area Reduction, Impervious Disconnection and Source Control Practices be utilized to achieve a Runoff Reduction Volume RRv that, if possible, equals the Water Quality Volume WQv. At a minimum, RRv must meet a minimum value which is a % of WQv dependent on the hydrologic soil group. The complete RRv calculations for each stormwater management areas are provided in the Stormwater Management Worksheets included in the appendices. A summary of the results are provided in the table below. Runoff'Reduction Volumes Stormwater Management Area WQv (cf) Min. RRv (cf) RRv Provided (cf) Southeast 1,359 272 272 Northwest 8,020 1,604 1,604 HydroCAD Analysis HydroCAD stormwater modeling software has been used to analyze the pre and post development stormwater runoff from the site. The developed site has been modeled as a series of subcatchments (discrete drainage areas), reaches and ponds as shown on the attached HydroCAD drainage diagram. As in the WQv and RRv analysis, the site has been divided into three stormwater management areas. All calculations are based upon the following: • All computations SCS TR -20, HydroCAD • 1 year, 24 hour storm - Type II rainfall = 2.2" 0 10 year, 24 hour storm - Type II rainfall = 3.6" • 50 year, 24 hour storm - Type II rainfall = 5.2" • 100 year, 24 hour storm - Type II rainfall = 6.5" • Soils — Belgrade, Farmington and Rhinebeck silt loams — hydrologic soil group C/D The attached HydroCAD calculations show the stormwater routing for the site and results for each of the subcatchments and ponds. M Channel Protection Volume Channel protection is required by the DEC Stormwater Management Design Manual. This requires 24 hour extended detention of the 1 year 24 hour storm. The HydroCAD analysis of the developed site shows that the Channel Protection Volume (CPv) is as presented in the table below: Required Channel Protection Volume Stormwater Management Area CPv Required (cf) Detention Volume Provided (cf) Southeast 11,413 17,377 Northwest 12,414 16,544 Overbank Flood Control Overbank flood control is required by the DEC Stormwater Management Design Manual. The overbank flood control requires that the peak discharge rate from the 10 year 24 hour storm be reduced to pre -development rates. HydroCAD analysis shows the pre and post development discharges from each Stormwater Management Area to be as follows: Overbank Flood Control Stormwater Management Area Predeveloped 10 yr storm (cfs) Postdeveloped 10 yr storm (cfs) Southeast 3.25 2.01 _ Northwest 2.00 1.53 Town of Queensbury Stormwater Regulations The Town of Queensbury Stormwater Regulations require that the peak discharge rate from the 50 year 24 hour storm be reduced to pre -development rates. HydroCAD analysis shows the pre and post development discharges from each Stormwater Management Area to be as follows: To%,m of QueensbuKy Stormwater Stormwater Management Area Predeveloped 50 yr storm (cfs) Postdeveloped 50 yr storm (cfs) Southeast 6.68 4.40 Northwest 4.13 3.68 Extreme Storm Control Extreme storm control is required by the DEC Stormwater Management Design Manual. The extreme storm control requires that the peak discharge from the 100 year storm be reduced to pre -development rates. HydroCAD analysis shows the pre and post development discharges from each Stormwater Management Area to be as follows: Extreme gtorm Control Stormwater Management Area Predeveloped 100 yr storm (cfs) Postdeveloped 100 yr storm (cfs) Southeast 9.72 6.43 Northwest 6.01 5.67 5 Conclusions The proposed stormwater management systems will treat and mitigate peak runoff, up through a 100 - year storm. As shown in the calculations they meet all of the green infrastructure requirements as well as the water quality and peak discharge requirements. Historical Places or Archaeological Resources The proposed project will not adversely affect any properties listed or eligible to be listed on the National Register of Historic Places; nor will it affect any properties mapped as archaeologically sensitive by OPRHP. A copy of the OPRHP project response is appended to this report. Temporary Erosion and Sediment Control Measures Erosion and sediment control measures will be incorporated into the construction of the project. These practices will comply with the New York State Department of Environmental Conservation publication entitled "New York Guidelines for Urban Erosion and Sediment Control" (the blue book). Separate erosion and sediment controls will be installed for each phase of construction. The following temporary erosion and sediment control devices will be utilized as shown on the Sediment and Erosion Control Plans. Sediment Control Fence: Silt fence shall be used to control erosion from sheet flow on slopes not to exceed 3 on 1. Concentrated flows shall not be directed toward the silt fence. The silt fence must be installed parallel to the contour lines to eliminate drainage along the fence. Temporary Seeding: Land that is stripped of vegetation will be seeded and planted as soon as possible. Any area that will remain cleared but not under construction for 10 days or longer will be seeded with a ryegrass mixture and mulched to stabilize soil until construction resumes. Temporary Silt Basin: A Temporary Silt Basins shall be constructed at low points outside of the pavement area and discharge clean stormwater into the drainage swale which shall be protected from sedimentation. Temporary Diversion Swales: Temporary diversion swales shall be constructed as required, either to divert clean stormwater runoff from newly graded areas or to direct sediment laden runoff to a sediment trapping device. Stabilized Construction Entrance: Existing roads will be protected by installation of a crushed stone blanket for cleaning construction vehicle wheels. Blankets shall be placed at any intersection of a construction road with a paved or publicly owned road. Stabilized construction entrances shall be installed as shown on the plans. Tree Protection: Trees to be preserved within areas of construction shall be protected by placing construction fencing around the drip lines. Construction workers will be directed to avoid storing equipment or soil under trees to be preserved. There shall be no parking of automobiles or construction vehicles under trees. Z Dust Control: Measures for dust control during construction shall be implemented as needed (daily water sprays will be used during dry conditions. In addition to water sprays, temporary mulching, temporary seeding and covering stockpiles with tarps shall be implemented when necessary. Rock Check Dam: Small stone check dams shall be constructed in any temporary drainage channels during construction. These dams shall be constructed in the locations shown on the plans and as necessary to control any drainage from the construction site which concentrates in flow paths or channels. Dams shall be constructed as detailed on the Erosion and Sediment Control Plan. Dams shall be cleaned of any sediment after each rainfall as needed. Control of Litter, Construction Debris and Construction Chemicals During the course of infrastructure and home construction, the site shall be kept clear of debris and litter which could be transported by water or wind. This material shall be picked up daily and shall be stored in waste debris containers where it is securely held. All petroleum products or other waste contaminants which are water soluble or could be dispersed and transported by stormwater shall be stored in covered containers and be regularly removed from the site and properly and legally disposed of. All petroleum or other hazardous materials shall be stored and handled in conformance with NYSDEC spill prevention and containment requirements. Sequence of Construction Construction sequencing is specified in detail on the Erosion and Sediment Control Plans. Maintenance of Temporary Erosion and Sediment Control Devices The sediment basins shall be inspected at least weekly and after every rain event by the Contractor. When 50% of the volume of the trap is full, The Contractor shall remove collected sediment and dispose of properly. The Contractor shall inspect the sediment control fence weekly and after every rain event and remove trapped sediment and maintain the devices in good working order. Permanent Erosion Control All pervious areas shall be graded, topsoil installed and seeded or planted as soon as practical. Seed beds shall be mulched with straw or hydro -mulch with tackifier and plant beds shall be mulched with pine bark mulch. Seeded areas on slopes over 3:1 shall be stabilized with erosion control netting as specified on the plans. Post -Construction Operation and Maintenance of Stormwater Control Devices All portions of the stormwater control system shall be inspected on a periodic basis and shall be cleaned and/or repaired as appropriate. • Vegetated swales - Inspect and clean fall and spring; mow twice per year. • Pocket Pond Forebays - Inspect monthly and clean fall and spring • Pocket Pond Outlet Structures - Inspect and clean grates monthly Keep maintenance records showing dates and descriptions of all inspections and maintenance. 7 Auuendix ■ USDA Soils Map ■ OPRHP Project Inquiry Response ■ Pre & PostDrainage Area Maps & HydroCAD Drainage Diagram ■ Pre & Post Developed Conditions — 1 Year Design Storm ■ Pre & Post Developed Conditions —10 Year Design Storm ■ Pre & Post Developed Conditions — 50 Year Design Storm ■ Pre & Post Developed Conditions —100 Year Design Storm 8 NNA ATF"R NIAN AGENIF.NT REPOR-F and S-1-0RNlVv A-TFR POLLL TION PRFN P�'-T1()N PLAN \ NR ATI VE GARVEY KI A Quaker Road Queerlsbur ., NY USDA SOILS MAP Or u,k. 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U a E O O cn 3 U O .3 d v a o r U F- O a O cn o cd O A N FU O O 4E. H o. o °1 s = Q 5 0 .. a w.e .x m ,v, cd C �a a •a O w a ,ga a a o A y' o d = 9 j a a ,T m n 3 > c°n W � 'o m ca° U V C7 V v a a rn fn cn m -0❑o❑Z a�®x0X O<-44(00>+..1oA►� ■ rn Q � � "I M G� v � a L O L TC/I Cl)v> 3 o va (n o a y -ri a G 40 N0 °1 s = Q 5 0 .. a w.e .x m ,v, cd C �a a •a O w a ,ga a a o A y' o d = 9 j a a ,T m n 3 > c°n W � 'o m ca° U V C7 V v a a rn fn cn m -0❑o❑Z a�®x0X O<-44(00>+..1oA►� ■ rn Q � � "I M G� e o e o a o 00 O N T O l� N O o0 O O A V F+ a 00 00 O c v o0 00 a r— C14 Q N 3 z T M � � N T V 00 O 0O O O U y y 0 F M NO > G N q � Cl. O O cti 01 y .. o W U cd w o m a> � d IM V w U w � w' H STORM1\ ITER .N1ANAGENIE\T REPORT and STORNiWk-FER POLLUAiON PRT' L.Is-IiC)d PLAN N -�RATI VE Otiaker Road Queensbury. OPRHP PROJECT INOUIRY RESPONSE NEW YORK STATE t3F OPPORTUNITY. ANDREW M. CUOMO Governor April 08, 2015 Parks, Recreation, and `Historic Preservation ROSE HARVEY Commissioner Mr. THOMAS NACE 169 Haviland Road Queensbury, NY 12804 Re: DEC Garvey KIA; new dealership 483 Quaker Road, Queensbury, NY 12804 15PRO1557 Dear Mr. NACE: Thank you for requesting the comments of the Office of Parks, Recreation and Historic Preservation (OPRHP). We have reviewed the project in accordance with the New York State Historic Preservation Act of 1980 (Section 14.09 of the New York Parks, Recreation and Historic Preservation Law). These comments are those of the OPRHP and relate only to Historic/Cultural resources. They do not include potential environmental impacts to New York State Parkland that may be involved in or near your project. Such impacts must be considered as part of the environmental review of the project pursuant to the State Environmental Quality Review Act (New York Environmental Conservation Law Article 8) and its implementing regulations (6 NYCRR Part 617). Based upon this review, it is the New York State Office of Parks, Recreation and Historic Preservation's opinion that your project will have no impact on archaeological and/or historic resources listed in or eligible for the New York State and National Registers of Historic Places. If further correspondence is required regarding this project, please be sure to refer to the OPRHP Project Review (PR) number noted above. Sincerely, Ruth L. Pierpont Deputy Commissioner for Historic Preservation Division for Historic Preservation P.O. Box 189, Waterford, New York 12188-0189 • (518) 237-8643 • %rww.nysparks.corn STORNM kj F'R NIANAGENIVAT R PO R-1, ST 0 R � I k% -k I'l I � P I N N N A R -A T I V E JA I ION PRFA LNTIO'N FT G-- R VE Y K LA, Quak-er Road (.L)uecn-sburyN-Y PRE & POST DRAINAGE AREA MAPS HvdroCAD DRAINAGE DIAGRAMS NACE ENGINEERING,P.C. 169 HAVILAND ROAD QUEENSBURY,NY 0 4000— GARVEY KIA DRAINAGE REPORT QUAKER ROAD, TOWN OF QUEENSBURY, EXISTING CONDITIONS SARATOGA COUNTY, NY JOB /47561 SCALE: NTS DATE: 4/16/2015 M y i'11 1 + � t 11� �� 19 l 44 NACE ENGINEERING, P.C. GARVEY KIA DRAINAGE REPORT 169 HAVILAND ROAD QUAKER ROAD, TOWN OFQUEENSBURY, PROPOSED CONDITIONS QUEENSBURY, NY SARATOGA COUNTY, NY JOB ,#47551 SCALE: NTS DATE: 4/16/2015 i P DRAINAGE TO NORTHWEST DRAINAGE TO SOUTHEAST NORT WEST PORTION OF SITE 1P SOUTHEAS OF' PORTION ITE A VEGETAT D SWALE VEGETAT D SWALE 3P 4P SOUTHEAST POND NORTHWEST POND RLPORT lint] G A RNT V KJ A Quaker Road Queens urN , N HvdroCAD RESULTS PRE & POST DEVELOPED CONDITIONS 1 -YEAR DESIGN STORM 47561 GARVEYKIA - proposed Type// 24 -hr 1 -YEAR Rainfall=2.20" Prepared by NACE ENGINEERING, P.C. Printed 4/11/2015 H droCADC3 9.10 s/n 03732 © 2010 H dfoCAD Software Solutions LLC -Page 2 Time span=5.00-20.00 hrs, dt=0.05 hrs, 301 points Runoff by SCS TR -20 method, UH=SCS Reach routing by Stor-Ind+Trans method - Pond routing by Stor-Ind method Subcatchment 1S: NORTHWEST Runoff Area=119,639 sf 69.14% Impervious Runoff Depth>1.25" Flow Length=200' Slope=0.0200 '/' Tc=2.0 min CN=91 Runoff=6.86 cfs 0.285 of Subcatchment 2S: SOUTHEAST Runoff Area=158,592 sf 46.23% Impervious Runoff Depth>0.86" Flow Length=130' Slope=0.0200 '/' Tc=1.6 min CN=85 Runoff=6.67 cfs 0.262 of Pond 1P: VEGETATED SWALE Peak Elev=328.28' Storage=4,591 cf Inflow=6.86 cfs 0.285 of Discarded=0.25 cfs 0.158 of Primary=3.87 cfs 0.090 of Outflow=4.11 cfs 0.248 of Pond 2P: VEGETATED SWALE Peak Elev=328.23' Storage=4,303 cf Inflow=6.67 cfs 0.262 of Discarded=0.24 cfs 0.148 of Primary=2.73 cfs 0.074 of Outflow=2.98 cfs 0.221 of Pond 3P: SOUTHEAST POND Peak Elev=326.16' Storage=25,592 cf Inflow=3.87 cfs 0.090 of Outflow=0.42 cfs 0.085 of Pond 4P: NORTHWEST POND Peak Elev=326.14' Storage=30,895 cf Inflow=2.73 cfs 0.074 of Outflow=0.23 cfs 0.064 of Total Runoff Area = 6.387 ac Runoff Volume = 0.548 of Average Runoff Depth = 1.03" 43.92% Pervious = 2.805 ac 56.08% Impervious = 3.582 ac 47561 GARVEYKIA -proposed Type// 24 -hr 1 -YEAR Rainfall=2.20" Prepared by NACE ENGINEERING, P.C. Printed 4/11/2015 HydroCADCD 9.10 s/n 03732 © 2010 HydroCAD Software Solutions LLC Pa�1e 3 Summaryfor Subcatchment1S: NORTHWEST PORTION OF SITE Runoff = 6.86 cfs @ 11.92 hrs, Volume= 0.285 af, Depth> 1.25" Runoff by SCS TR -20 method, UH=SCS, Time Span= 5.00-20.00 hrs, dt= 0.05 hrs Type II 24 -hr 1 -YEAR Rainfall=2.20" Area (sf) CN Description 8,923 98 ROOF 73,794 98 PAVEMENT 36:922 74 >75% Grass cover. Good. HSG C 119,639 91 Weighted Average 36,922 30.86% Pervious Area 82,717 Smooth surfaces n=0.011 P2=2.40" 69.14% Impervious Area Tc Length Slope Velocity Capacity Description (min) (feet) (ft/ft) (ft/sec) (cfs) cfs) 1.4 100 0.0200 1.19 Sheet Flow, ACROSS PAVEMENT Smooth surfaces n=0.011 P2=2.40" 0.6 100 0.0200 2.87 Shallow Concentrated Flow, ACROSS PAVEMENT TO SWALE Paved Kv= 20.3 fps ew Runoff = 200 Total Summaryfor Subcatchment2S: SOUTHEAST PORTION OF SITE 6.67 cfs @ 11.92 hrs, Volume= 0.262 af, Depth> 0.86" Runoff by SCS TR -20 method, UH=SCS, Time Span= 5.00-20.00 hrs, dt= 0.05 hrs Type II 24 -hr 1 -YEAR Rainfall=2.20" Area (sf) CN Description _ 9,123 98 ROOF 64,197 98 PAVEMENT 85.272 74 >75% Grass cover. Good. HSG C 158,592 85 Weighted Average 85,272 53.77% Pervious Area 73,320 46.23% Impervious Area Tc Length Slope Velocity Capacity Description (min) (feet) (ft/ft) (ft/sec) cfs) 1.4 100 0.0200 1.19 Sheet Flow, ACROSS PAVEMENT Smooth surfaces n= 0.011 P2= 2.40" 0.2 30 0.0200 2.87 Shallow Concentrated Flow, ACROSS PAVEMENT TO SWALE Paved Kv= 20.3 fps 1.6 130 Total 47561 GARVEYKIA - proposed Type// 24 -hr 1 -YEAR Rainfall=2.20" Prepared by NACE ENGINEERING, P.C. Printed 4/11/2015 HvdroCAD® 9.10 s/n 03732 © 2010 HvdroCAD Software Solutions LLC Pane 4 Summaryfor Pond 1 P: VEGETATEDSWALE Inflow Area = 2.747 ac, 69.14% Impervious, Inflow Depth > 1.25" for 1 -YEAR event Inflow = 6.86 cfs @ 11.92 hrs, Volume= 0.285 of Outflow = 4.11 cfs @ 12.00 hrs, Volume= 0.248 af, Atten= 40%, Lag= 4.7 min Discarded = 0.25 cfs @ 12.00 hrs, Volume= 0.158 of Primary = 3.87 cfs @ 12.00 hrs, Volume= 0.090 of Routing by Stor-Ind method, Time Span= 5.00-20.00 hrs, dt= 0.05 hrs Peak Elev= 328.28' @ 12.00 hrs Surf.Area= 5,177 sf Storage= 4,591 cf Plug -Flow detention time= 107.2 min calculated for 0.248 of (87% of inflow) Center -of -Mass det. time= 66.0 min ( 838.2 - 772.3 ) Volume Invert Avail.Storage Storage Description #1 327.00' 5,774 cf 5.00'W x 400.00'L x 1.50'H Prismatoid Z=3.0 Device Routinq Invert Outlet Devices #1 Primary 328.00' 10.0' long x 2.0' 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 Coef. (English) 2.54 2.61 2.61 2.60 2.66 2.70 2.77 2.89 2.88 2.85 3.07 3.20 3.32 #2 Discarded 327.00' 2.000 in/hr Exfiltration over Wetted area Discarded OutFlow Max=0.25 cfs @ 12.00 hrs HW=328.28' (Free Discharge) t2=Exfiltration (Exfiltration Controls 0.25 cfs) Primary OutFlow Max=3.82 cfs @ 12.00 hrs HW=328.28' (Free Discharge) L1= Broad -Crested Rectangular Weir (Weir Controls 3.82 cfs @ 1.36 fps) Summary for Pond 2P: VEGETATEDSWALE Inflow Area = 3.641 ac, 46.23% Impervious, Inflow Depth > 0.86" for 1 -YEAR event Inflow = 6.67 cfs @ 11.92 hrs, Volume= 0.262 of Outflow = 2.98 cfs @ 12.01 hrs, Volume= 0.221 af, Atten= 55%, Lag= 5.8 min Discarded = 0.24 cfs @ 12.01 hrs, Volume= 0.148 of Primary = 2.73 cfs @ 12.01 hrs, Volume= 0.074 of Routing by Stor-Ind method, Time Span= 5.00-20.00 hrs, dt= 0.05 hrs Peak Elev= 328.23' @ 12.01 hrs Surf.Area= 5,034 sf Storage= 4,303 cf Plug -Flow detention time= 119.5 min calculated for 0.221 of (84% of inflow) Center -of -Mass det. time= 71.5 min ( 863.9 - 792.4 ) Volume Invert Avail.Storage Storage Description #1 327.00' 5,774 cf 5.00'W x 400.00'L x 1.50'H Prismatoid Z=3.0 Device Routing Invert Outlet Devices #1 Primary 328.00' 10.0' long x 2.0' 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 47561 GARVEY KIA - proposed Type// 24 -hr 1 -YEAR Rainfall=2.20" Prepared by NACE ENGINEERING, P.C. Printed 4/11/2015 HydroCAD®R 9.10 s/n 03732 © 2010 HydroCAD Software Solutions LLC _ Pane 5 2.50 3.00 3.50 Coef. (English) 2.54 2.61 2.61 2.60 2.66 2.70 2.77 2.89 2.88 2.85 3.07 3.20 3.32 #2 Discarded 327.00' 2.000 in/hr Exfiltration over Wetted area Qiscarded OutFlow Max=0.24 cfs @ 12.01 hrs HW=328.22' (Free Discharge) 2=Exfiltration (Exfiltration Controls 0.24 cfs) Primary OutFlow Max=2.56 cfs @ 12.01 hrs HW=328.22' (Free Discharge) t-1=113road-Crested Rectangular Weir (Weir Controls 2.56 cfs @ 1.18 fps) Summaryfor Pond 3P: SOUTHEASTPOND Inflow Area = 2.747 ac, 69.14% Impervious, Inflow Depth = 0.39" for 1 -YEAR event Inflow = 3.87 cfs @ 12.00 hrs, Volume= 0.090 of Outflow = 0.42 cfs @ 12.50 hrs, Volume= 0.085 af, Atten= 89%, Lag= 30.0 min Primary = 0.42 cfs @ 12.50 hrs, Volume= 0.085 of Routing by Stor-Ind method, Time Span= 5.00-20.00 hrs, dt= 0.05 hrs Starting Elev= 326.00' Surf.Area= 15,936 sf Storage= 22,997 cf Peak Elev= 326.16' @ 12.50 hrs Surf.Area= 16,398 sf Storage= 25,592 cf (2,595 cf above start) Plug -Flow detention time= (not calculated: initial storage excedes outflow) Center -of -Mass det. time= 104.5 min ( 839.4 - 734.9 ) Volume Invert Avail.Storaae Storaae Description #1 321.00' 60,662 cf Custom Stage Data (Prismatic) Listed below (Recalc) Elevation Surf.Area Inc.Store Cum.Store (feet) (sq -ft) (cubic -feet) (cubic -feet) 321.00 0 0 0 322.00 126 63 63 323.00 3,274 1,700 1,763 324.00 4,859 4,067 5,830 325.00 6,770 5,815 11,644 326.00 15,936 11,353 22,997 327.00 18,817 17,377 40,374 328.00 21,760 20,289 60,662 Device Routina Invert Outlet Devices #1 Primary 327.30' 1.0' long Sharp -Crested Rectangular Weir 2 End Contraction(s) #2 Primary 326.00' 2.0' long Sharp -Crested Rectangular Weir 2 End Contractions) Primary OutFlow Max=0.41 cfs @ 12.50 hrs HW=326.16' (Free Discharge) 1:1=Sharp-Crested Rectangular Weir ( Controls 0.00 cfs) 2=Sharp-Crested Rectangular Weir (Weir Controls 0.41 cfs @ 1.31 fps) 47561 GARVEYKIA - proposed Type// 24 -hr 1 -YEAR Rainfall=2.20" Prepared by NACE ENGINEERING, P.C. Printed 4/11/2015 HvdroCAD® 0.10 s/n 03732 © 2010 HvdroCAD Software Solutions LLC Paoe 6 Summaryfor Pond 4P: NORTHWESTPOND Inflow Area = 3.641 ac, 46.23% Impervious, Inflow Depth = 0.24" for 1 -YEAR event Inflow = 2.73 cfs @ 12.01 hrs, Volume= 0.074 of Outflow = 0.23 cfs @ 12.82 hrs, Volume= 0.064 af, Atten= 92%, Lag= 48.2 min Primary = 0.23 cfs @ 12.82 hrs, Volume= 0.064 of Routing by Stor-Ind method, Time Span= 5.00-20.00 hrs, dt= 0.05 hrs Starting Elev= 326.00' Surf.Area= 15,478 sf Storage= 28,672 cf Peak Elev= 326.14' @ 12.82 hrs Surf.Area= 15,781 sf Storage= 30,895 cf (2,223 cf above start) Plug -Flow detention time= (not calculated: initial storage excedes outflow) Center -of -Mass det. time= 130.5 min ( 871.6 - 741.0 ) Volume Invert Avail.Storaae Storage Description #1 321.00' 63,921 cf Custom Stage Data (Prismatic) Listed below (Recalc) Elevation Surf.Area Inc.Store Cum.Store (feet) (sa-ft) (cubic -feet) (cubic -feet) 321.00 0 0 0 322.00 190 95 95 323.00 5,341 2,766 2,861 324.00 6,879 6,110 8,971 325.00 8,523 7,701 16,672 326.00 15,478 12,001 28,672 327.00 17,610 16,544 45,216 328.00 19,800 18,705 63,921 Device Routine Invert Outlet Devices #1 Primary 327.30' 1.0' long Sharp -Crested Rectangular Weir 2 End Contraction(s) #2 Primary 326.00' 1.3' long Sharp -Crested Rectangular Weir 2 End Contraction(s) Primary OutFlow Max=0.22 cfs @ 12.82 hrs HW=326.14' (Free Discharge) �__2=S 1=Sharp-Crested Rectangular Weir ( Controls 0.00 cfs) harp -Crested Rectangular Weir (Weir Controls 0.22 cfs @ 1.23 fps) HvdroCAD RESULTS PRE & POST DEVELOPED CONDITIONS 10 -YEAR DESIGN STORM 47561 GARVEY KIA -exist Type // 24 -hr 10 -YEAR Rainfall=3.60" Prepared by NACE ENGINEERING, P.C. Printed 4/11/2015 HvdroCAD® 9.10 s/n 03732 © 2010 HvdroCAD Software Solutions LLC Paae 2 Summaryfor Subcatchment1S: DRAINAGETO NORTHWEST Runoff = 2.00 cfs @ 12.48 hrs, Volume= 0.277 af, Depth= 1.25" Runoff by SCS TR -20 method, UH=SCS, Time Span= 0.00-30.00 hrs, dt= 0.05 hrs Type II 24 -hr 10 -YEAR Rainfall=3.60" Area (sf) CN Description 116,237 73 Woods, Fair, HSG C 116,237 100.00% Pervious Area Tc Length Slope Velocity Capacity Description (min) (feet) (ft/ft) (fUsec) (cfs) 39.5 100 0.0250 0.04 Sheet Flow, ACROSS GROUND Woods: Dense underbrush n= 0.800 P2= 2.40" 6.7 320 0.0250 0.79 Shallow Concentrated Flow, ACROSS GROUND Woodland Kv= 5.0 fps 46.2 Runoff = 420 Total Summaryfor Subcatchment2S: DRAINAGETO SOUTHEAST 3.25 cfs @ 12.36 hrs, Volume= 0.387 af, Depth= 1.25" Runoff by SCS TR -20 method, UH=SCS, Time Span= 0.00-30.00 hrs, dt= 0.05 hrs Type II 24 -hr 10 -YEAR Rainfall=3.60" Area (sf) CN Description 161.995 73 Woods, Fair, HSG C 161,995 100.00% Pervious Area Tc Length Slope Velocity Capacity Description )min) (feet) (ft/ft) (ft/sec) (cfs) 31.8 100 0.0430 0.05 Sheet Flow, ACROSS GROUND Woods: Dense underbrush n= 0.800 P2= 2.40" 5.5 340 0.0430 1.04 Shallow Concentrated Flow, ACROSS GROUND Woodland Kv= 5.0 fps 37.3 440 Total 47561 GARVEY KIA - proposed Type// 24 -hr 10 -YEAR Rainfall=3.60" Prepared by NACE ENGINEERING, P.C. Printed 4/11/2015 HydroCADQ 9.10 s/n 03732 9 2010 I-ivdroCAD Software Solutions LLC Pare 7 Time span=5.00-20.00 hrs, dt=0.05 hrs, 301 points Runoff by SCS TR -20 method, UH=SCS Reach routing by Stor-Ind+Trans method - Pond routing by Stor-Ind method Subcatchment 1S: NORTHWEST Runoff Area= 119,639 sf 69.14% Impervious Runoff Depth>2.47" Flow Length=200' Slope=0.0200 '/' Tc=2.0 min CN=91 Runoff=13.00 cfs 0.566 of Subcatchment 2S: SOUTHEAST Runoff Area=158,592 sf 46.23% Impervious Runoff Depth>1.95" Flow Length=130' Slope=0.0200 '/' Tc=1.6 min CN=85 Runoff=14.60 cfs 0.593 of Pond 1P: VEGETATED SWALE Peak Elev=328.68' Storage=5,774 cf Inflow=13.00 cfs 0.566 of Discarded=0.28 cfs 0.193 of Primary= 14.72 cfs 0.311 of Outflow= 15. 00 cfs 0.504 of Pond 2P: VEGETATED SWALE Peak EIev=328.73' Storage=5,774 cf Inflow=14.60 cfs 0.593 of Discarded=0.28 cfs 0.178 of Primary=16.31 cfs 0.346 of Outflow=16.58 cfs 0.524 of Pond 3P: SOUTHEAST POND Peak EIev=326.47' Storage=30,804 cf Inflow=14.72 cfs 0.311 of Outflow=2.01 cfs 0.303 of Pond 4P: NORTHWEST POND Peak EIev=326.54' Storage=37,290 cf Inflow=16.31 cfs 0.346 of Outflow=1.53 cfs 0.327 of Total Runoff Area = 6.387 ac Runoff Volume = 1.158 of Average Runoff Depth = 2.18" 43.92% Pervious = 2.805 ac 56.08% Impervious = 3.582 ac 47561 GARVEYKIA - proposed Type// 24 -hr 10 -YEAR Rainfall=3.60" Prepared by NACE ENGINEERING, P.C. Printed 4/11/2015 HvdroCAD® 9.10 s/n 03732 © 2010 HvdroCAD Software Solutions LLC Pan? 8 Summary for Subcatchment1S: NORTHWEST PORTION OF SITE Runoff = 13.00 cfs @ 11.92 hrs, Volume= 0.566 af, Depth> 2.47" Runoff by SCS TR -20 method, UH=SCS, Time Span= 5.00-20.00 hrs, dt= 0.05 hrs Type II 24 -hr 10 -YEAR Rainfall=3.60" Area (sf) CN Description 8,923 98 ROOF 73,794 98 PAVEMENT 36,922 74 >75% Grass cover. Good, HSG C 119,639 91 Weighted Average 36,922 30.86% Pervious Area 82,717 Smooth surfaces n=0.011 P2=2.40" 69.14% Impervious Area Tc Length Slope Velocity Capacity Description (min) (feet) (ftift) (ft/sec) (cfs) 1.4 100 0.0200 1.19 Sheet Flow, ACROSS PAVEMENT Smooth surfaces n=0.011 P2=2.40" 0.6 100 0.0200 2.87 Shallow Concentrated Flow, ACROSS PAVEMENT TO SWALE Paved Kv= 20.3 fps 2.0 Runoff = 200 Total Summaryfor Subcatchment2S: SOUTH EASTPORTION OF SITE 14.60 cfs @ 11.91 hrs, Volume= 0.593 af, Depth> 1.95" Runoff by SCS TR -20 method, UH=SCS, Time Span= 5.00-20.00 hrs, dt= 0.05 hrs Type II 24 -hr 10 -YEAR Rainfall=3.60" Area (sf) CN Description 9,123 98 ROOF 64,197 98 PAVEMENT 85,272 74 >75% Grass cover. Good, HSG C 158,592 85 Weighted Average 85,272 53.77% Pervious Area 73,320 46.23% Impervious Area Tc Length Slope Velocity Capacity Description (min) (feet) (ft/ft) (ft/sec) (cfs) 1.4 100 0.0200 1.19 Sheet Flow, ACROSS PAVEMENT Smooth surfaces n= 0.011 P2= 2.40" 0.2 30 0.0200 2.87 Shallow Concentrated Flow, ACROSS PAVEMENT TO SWALE Paved Kv= 20.3 fps 1.6 130 Total 47561 GARVEY KIA - proposed Type 1124 -hr 10 -YEAR Rainfall=3.60" Prepared by NACE ENGINEERING, P.C. Printed 4/11/2015 HydroCADO 9.10 s/n 03732 © 2010 HvdroCAD Software Solutions LLC Paae 9 Summaryfor Pond 1 P: VEGETATEDSWALE Inflow Area = 2.747 ac, 69.14% Impervious, Inflow = 13.00 cfs @ 11.92 hrs, Volume Outflow = 15.00 cfs @ 11.95 hrs, Volume Discarded = 0.28 cfs @ 11.93 hrs, Volume Primary = 14.72 cfs @ 11.95 hrs, Volume Inflow Depth > 2.47" 0.566 of 0.504 af, = 0.193 of 0.311 of for 10 -YEAR event Atten= 0%, Lag= 1.9 min Routing by Stor-Ind method, Time Span= 5.00-20.00 hrs, dt= 0.05 hrs Peak Elev= 328.68' @ 11.95 hrs Surf.Area= 5,726 sf Storage= 5,774 cf Plug -Flow detention time= 63.1 min calculated for 0.502 of (89% of inflow) Center -of -Mass det. time= 26.7 min ( 783.1 - 756.5 ) Volume Invert Avail.Storage Storage Description #1 327.00' 5,774 cf 5.00'W x 400.00'L x 1.50'H Prismatoid Z=3.0 Device Ro Invert Outlet Devices #1 Primary 328.00' 10.0' long x 2.0' 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 Coef. (English) 2.54 2.61 2.61 2.60 2.66 2.70 2.77 2.89 2.88 2.85 3.07 3.20 3.32 #2 Discarded 327.00' 2.000 in/hr Exfiltration over Wetted area Discarded OutFlow Max=0.27 cfs @ 11.93 hrs HW=328.61' (Free Discharge) t2=Exfiltration (Exfiltration Controls 0.27 cfs) Primary OutFlow Max=14.32 cfs @ 11.95 hrs HW=328.67' (Free Discharge) =Broad -Crested Rectangular Weir (Weir Controls 14.32 cfs @ 2.13 fps) Summaryfor Pond 2P: VEGETATEDSWALE Inflow Area = 3.641 ac, Inflow = 14.60 cfs @ Outflow = 16.58 cfs @ Discarded = 0.28 cfs @ Primary = 16.31 cfs @ 46.23% Impervious, Inflow Depth > 1.95" 11.91 hrs, Volume= 0.593 of 11.94 hrs, Volume= 0.524 af, 11.93 hrs, Volume= 0.178 of 11.94 hrs, Volume= 0.346 of for 10 -YEAR event Atten= 0%, Lag= 2.0 min Routing by Stor-Ind method, Time Span= 5.00-20.00 hrs, dt= 0.05 hrs Peak Elev= 328.73' @ 11.94 hrs Surf.Area= 5,726 sf Storage= 5,774 cf Plug -Flow detention time= 59.5 min calculated for 0.522 of (88% of inflow) Center -of -Mass det. time= 21.5 min ( 796.4 - 774.9 ) Volume Invert Avail.Storaae Storage Description #1 327.00' 5,774 cf 5.00'W x 400.00'L x 1.50'H Prismatoid Z=3.0 Device Routina Invert Outlet Devices #1 Primary 328.00' 10.0' long x 2.0' 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 47561 GARVEY KIA - proposed Type// 24 -hr 10 -YEAR Rainfall=3.60" Prepared by NACE ENGINEERING, P.C. Printed 4/11/2015 HvdroCAD® 9.10 s/n 03732 © 2010 HvdroCAD Software Solutions LLC Pane 10 2.50 3.00 3.50 Coef. (English) 2.54 2.61 2.61 2.60 2.66 2.70 2.77 2.89 2.88 2.85 3.07 3.20 3.32 #2 Discarded 327.00' 2.000 in/hr Exfiltration over Wetted area Discarded OutFlow Max=0.27 cfs @ 11.93 hrs HW=328.64' (Free Discharge) L2=Exfiltration (Exfiltration Controls 0.27 cfs) Primary OutFlow Max=15.48 cfs @ 11.94 hrs HW=328.71' (Free Discharge) t1=13road-Crested Rectangular Weir (Weir Controls 15.48 cfs @ 2.19 fps) Summaryfor Pond 3P: SOUTHEASTPOND Inflow Area = 2.747 ac, 69.14% Impervious, Inflow Depth = 1.36" for 10 -YEAR event Inflow = 14.72 cfs @ 11.95 hrs, Volume= 0.311 of Outflow = 2.01 cfs @ 12.19 hrs, Volume= 0.303 af, Atten= 86%, Lag= 14.3 min Primary = 2.01 cfs @ 12.19 hrs, Volume= 0.303 of Routing by Stor-Ind method, Time Span= 5.00-20.00 hrs, dt= 0.05 hrs Starting Elev= 326.00' Surf.Area= 15,936 sf Storage= 22,997 cf Peak Elev= 326.47'@ 12.19 hrs Surf.Area= 17,290 sf Storage= 30,804 cf (7,807 cf above start) Plug -Flow detention time= (not calculated: initial storage excedes outflow) Center -of -Mass det. time= 74.6 min ( 811.7 - 737.1 ) Volume Invert Avail.Storaae Storage Description #1 321.00' 60,662 cf Custom Stage Data (Prismatic) Listed below (Recalc) Elevation Surf.Area Inc.Store Cum.Store (feet) (sq -ft) (cubic -feet) (cubic -feet) 321.00 0 0 0 322.00 126 63 63 323.00 3,274 1,700 1,763 324.00 4,859 4,067 5,830 325.00 6,770 5,815 11,644 326.00 15,936 11,353 22,997 327.00 18,817 17,377 40,374 328.00 21,760 20,289 60,662 Device Routina Invert Outlet Devices #1 Primary 327.30' 1.0' long Sharp -Crested Rectangular Weir 2 End Contraction(s) #2 Primary 326.00' 2.0' long Sharp -Crested Rectangular Weir 2 End Contractions) Primary OutFlow Max=2.01 cfs @ 12.19 hrs HW=326.47' (Free Discharge) 1I=Sharp-Crested Rectangular Weir ( Controls 0.00 cfs) 2=S ha rp-C rested Rectangular Weir (Weir Controls 2.01 cfs @ 2.24 fps) 47561 GARVEYKIA - proposed Type// 24 -hr 10 -YEAR Rainfa11=3.60" Prepared by NACE ENGINEERING, P.C. Printed 4/11/2015 HydroCAD® 9.10 s/n 03732 @2010 HydroCAD Software Solutions LLC Paae 11 Summaryfor Pond 4P: NORTHWESTPOND Inflow Area = 3.641 ac, 46.23% Impervious, Inflow Depth = 1.14" for 10 -YEAR event Inflow = 16.31 cfs @ 11.94 hrs, Volume= 0.346 of Outflow = 1.53 cfs @ 12.31 hrs, Volume= 0.327 af, Atten= 91 %, Lag= 21.7 min Primary = 1.53 cfs @ 12.31 hrs, Volume= 0.327 of Routing by Stor-Ind method, Time Span= 5.00-20.00 hrs, dt= 0.05 hrs Starting Elev= 326.00' Surf.Area= 15,478 sf Storage= 28,672 cf Peak Elev= 326.54' @ 12.31 hrs Surf.Area= 16,623 sf Storage= 37,290 cf (8,618 cf above start) Plug -Flow detention time= (not calculated: initial storage excedes outflow) Center -of -Mass det. time= 93.1 min ( 839.3 - 746.2 ) Volume Invert Avail.Storage Storage Description #1 321.00' 63,921 cf Custom Stage Data (Prismatic) Listed below (Recalc) Elevation Surf.Area Inc.Store Cum.Store (feet) (sq -ft) (cubic -feet) (cubic -feet) 321.00 0 0 0 322.00 190 95 95 323.00 5,341 2,766 2,861 324.00 6,879 6,110 8,971 325.00 8,523 7,701 16,672 326.00 15,478 12,001 28,672 327.00 17,610 16,544 45,216 328.00 19,800 18,705 63,921 Device Routing Invert Outlet Devices #1 Primary 327.30' 1.0' long Sharp -Crested Rectangular Weir 2 End Contraction(s) #2 Primary 326.00' 1.3' long Sharp -Crested Rectangular Weir 2 End Contractions) Primary OutFlow Max=1.53 cfs @ 12.31 hrs HW=326.54' (Free Discharge) �__1=Sharp-Crested Rectangular Weir ( Controls 0.00 cfs) 2=Sharp-Crested Rectangular Weir (Weir Controls 1.53 cfs @ 2.40 fps) K, F PORT Alld ION PRI -,� ENTION III HydroCAD RESULTS PRE & POST DEVELOPED CONDIITONS 50 -YEAR DESIGN STORM 47561 GARVEY KIA - exist Type// 24 -hr 50 -YEAR Rainfall=5.20" Prepared by NACE ENGINEERING, P.C. Printed 4/11/2015 HvdroCADO 9.10 s/n 03732 © 2010 HvdroCAD Software Solutions LLC Paae 3 Summaryfor Subcatchment1S: DRAINAGETO NORTHWEST Runoff = 4.13 cfs @ 12.46 hrs, Volume= 0.542 af, Depth= 2.44" Runoff by SCS TR -20 method, UH=SCS, Time Span= 0.00-30.00 hrs, dt= 0.05 hrs Type II 24 -hr 50 -YEAR Rainfall=5.20" Area (sfl CN Description 116,237 73 Woods. Fair. HSG C 116,237 100.00% Pervious Area Tc Length Slope Velocity Capacity Description (min) (feet) (fUft) (ft/sec) (cfs) 39.5 100 0.0250 0.04 Sheet Flow, ACROSS GROUND Woods: Dense underbrush n= 0.800 P2= 2.40" 6.7 320 0.0250 0.79 Shallow Concentrated Flow, ACROSS GROUND Woodland Kv= 5.0 fos 46.2 420 Total Summaryfor Subcatchment2S: DRAINAGETO SOUTHEAST Runoff = 6.68 cfs @ 12.34 hrs, Volume= 0.756 af, Depth= 2.44" Runoff by SCS TR -20 method, UH=SCS, Time Span= 0.00-30.00 hrs, dt= 0.05 hrs Type II 24 -hr 50 -YEAR Rainfall=5.20" Area (sf) CN Description 161,995 73 Woods. Fair, HSG C 161,995 100.00% Pervious Area Tc Length Slope Velocity Capacity Description (min) (feet) (ft/ft) (ft/sec) (cfs) 31.8 100 0.0430 0.05 Sheet Flow, ACROSS GROUND Woods: Dense underbrush n= 0.800 P2= 2.40" 5.5 340 0.0430 1.04 Shallow Concentrated Flow, ACROSS GROUND Woodland Kv= 5.0 fps 37.3 440 Total 47561 GARVEY KIA - proposed Type 1124 -hr 50 -YEAR Rainfall=5.20" Prepared by NACE ENGINEERING, P.C. Printed 4/11/2015 HvdroCADO 9.10 s/n 03732 © 2010 HvdroCAD Software Solutions LLC Paae 12 Time span=5.00-20.00 hrs, dt=0.05 hrs, 301 points Runoff by SCS TR -20 method, UH=SCS Reach routing by Stor-Ind+Trans method - Pond routing by Stor-Ind method Subcatchment 1S: NORTHWEST Runoff Area=1 19,639 sf 69.14% Impervious Runoff Depth>3.92" Flow Length=200' Slope=0.0200 '/' Tc=2.0 min CN=91 Runoff=19.97 cfs 0.897 of Subcatchment 2S: SOUTHEAST Runoff Area=158,592 sf 46.23% Impervious Runoff Depth>3.32" Flow Length= 130' Slope=0.0200 '/' Tc=1.6 min CN=85 Runoff=24.05 cfs 1.008 of Pond 1P: VEGETATED SWALE Peak Elev=328.85' Storage=5,774 cf Inflow=19.97 cfs 0.897 of Discarded=0.27 cfs 0.220 of Primary=20.42 cfs 0.604 of Outflow=20.69 cfs 0.824 of Pond 2P: VEGETATED SWALE Peak Elev=328.96' Storage=5,774 cf Inflow=24.05 cfs 1.008 of Discarded=0.27 cfs 0.205 of Primary=24.60 cfs 0.728 of Outflow=24.87 cfs 0.933 of Pond 3P: SOUTHEAST POND Peak Elev=326.81' Storage=36,906 cf Inflow=20.42 cfs 0.604 of Outflow=4.40 cfs 0.590 of Pond 4P: NORTHWEST POND Peak Elev=327.02' Storage=45,520 cf Inflow=24.60 cfs 0.728 of Outflow=3.68 cfs 0.692 of Total Runoff Area = 6.387 ac Runoff Volume = 1.905 of Average Runoff Depth = 3.58" 43.92% Pervious = 2.805 ac 56.08% Impervious = 3.582 ac 47561 GARVEY KIA - proposed Type 1124 -hr 50 -YEAR Rainfall=5.20" Prepared by NACE ENGINEERING, P.C. Printed 4/11/2015 HvdroCADO 9.10 s/n 03732 © 2010 HvdroCAD Software Solutions LLC Paae 13 Summaryfor Subcatchment1 S: NORTHWEST PORTION OF SITE Runoff = 19.97 cfs @ 11.91 hrs, Volume= 0.897 af, Depth> 3.92" Runoff by SCS TR -20 method, UH=SCS, Time Span= 5.00-20.00 hrs, dt= 0.05 hrs Type II 24 -hr 50 -YEAR Rainfall=5.20" Area (sf) CN Description 8,923 98 ROOF 73,794 98 PAVEMENT 36.922 74 >75% Grass cover. Good. HSG C 119,639 91 Weighted Average 36,922 30.86% Pervious Area 82,717 69.14% Impervious Area Tc Length Slope Velocity Capacity Description (min) (feet) (ft/ft) (ft/sec) (cfs) 1.4 100 0.0200 1.19 Sheet Flow, ACROSS PAVEMENT Smooth surfaces n= 0.011 P2= 2.40" 0.6 100 0.0200 2.87 Shallow Concentrated Flow, ACROSS PAVEMENT TO SWALE Paved Kv= 20.3 fps 2.0 Runoff = 200 Total Summaryfor Subcatchment2S: SOUTHEAST PORTION OF SITE 24.05 cfs @ 11.91 hrs, Volume= 1.008 af, Depth> 3.32" Runoff by SCS TR -20 method, UH=SCS, Time Span= 5.00-20.00 hrs, dt= 0.05 hrs Type II 24 -hr 50 -YEAR Rainfall=5.20" Area (sf) CN Description 9,123 98 ROOF 64,197 98 PAVEMENT 85.272 74 >75% Grass cover. Good. HSG C 158,592 85 Weighted Average 85,272 53.77% Pervious Area 73,320 46.23% Impervious Area Tc Length Slope Velocity Capacity Description (min) (_feet) (ft/ft) (ft/sec) (cfs) 1.4 100 0.0200 1.19 Sheet Flow, ACROSS PAVEMENT Smooth surfaces n= 0.011 P2= 2.40" 0.2 30 0.0200 2.87 Shallow Concentrated Flow, ACROSS PAVEMENT TO SWALE Paved Kv= 20.3 fps 1.6 130 Total 47561 GARVEY KIA - proposed Type 11 24 -hr 50 -YEAR Rainfall=5.20" Prepared by NACE ENGINEERING, P.C. Printed 4/11/2015 HvdroCADO 9.10 s/n 03732 0 2010 HydroCAD Software Solutions LLC Paae 14 Summaryfor Pond 1 P: VEGETATEDSWALE Inflow Area = 2.747 ac, 69.14% Impervious, Inflow = 19.97 cfs @ 11.91 hrs, Volume Outflow = 20.69 cfs @ 11.91 hrs, Volume Discarded = 0.27 cfs @ 11.85 hrs, Volume Primary = 20.42 cfs @ 11.91 hrs, Volume Inflow Depth > 3.92" 0.897 of 0.824 af, = 0.220 of = 0.604 of for 50 -YEAR event Atten= 0%, Lag= 0.0 min Routing by Stor-Ind method, Time Span= 5.00-20.00 hrs, dt= 0.05 hrs Peak Elev= 328.85'@ 11.91 hrs Surf.Area= 5,726 sf Storage= 5,774 cf Plug -Flow detention time= 47.9 min calculated for 0.824 of (92% of inflow) Center -of -Mass det. time= 17.9 min ( 764.9 - 746.9 ) Volume Invert Avail.Storage Storaqe Description #1 327.00' 5,774 cf 5.00'W x 400.00'L x 1.50'H Prismatoid Z=3.0 Device Routinq Invert Outlet Devices #1 Primary 328.00' 10.0' long x 2.0' 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 Coef. (English) 2.54 2.61 2.61 2.60 2.66 2.70 2.77 2.89 2.88 2.85 3.07 3.20 3.32 #2 Discarded 327.00' 2.000 in/hr Exfiltration over Wetted area Discarded OutFlow Max=0.27 cfs @ 11.85 hrs HW=328.66' (Free Discharge) L2=Exfiltration (Exfiltration Controls 0.27 cfs) Primary OutFlow Max=19.72 cfs @ 11.91 hrs HW=328.83' (Free Discharge) 't1=Broad-Crested Rectangular Weir (Weir Controls 19.72 cfs @ 2.38 fps) Summaryfor Pond 2P: VEGETATEDSWALE Inflow Area = 3.641 ac, Inflow = 24.05 cfs @ Outflow = 24.87 cfs @ Discarded = 0.27 cfs @ Primary = 24.60 cfs @ 46.23% Impervious, Inflow Depth > 3.32" 11.91 hrs, Volume= 1.008 of 11.93 hrs, Volume= 0.933 af, 11.85 hrs, Volume= 0.205 of 11.93 hrs, Volume= 0.728 of for 50 -YEAR event Atten= 0%, Lag= 1.4 min Routing by Stor-Ind method, Time Span= 5.00-20.00 hrs, dt= 0.05 hrs Peak Elev= 328.96'@ 11.93 hrs Surf.Area= 5,726 sf Storage= 5,774 cf Plug -Flow detention time= 41.4 min calculated for 0.930 of (92% of inflow) Center -of -Mass det. time= 14.6 min ( 777.3 - 762.7 ) Volume Invert Avail.Storage Storage Description #1 327.00' 5,774 cf 5.00'W x 400.00'L x 1.50'H Prismatoid Z=3.0 Device Routing Invert Outlet Devices #1 Primary 328.00' 10.0' long x 2.0' 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 47561 GARVEY KIA - proposed Type 1124 -hr 50 -YEAR Rainfall=5.20" Prepared by NACE ENGINEERING, P.C. Printed 4/11/2015 HvdroCAD@ 9.10 s/n 03732 © 2010 HvdroCAD Software Solutions LLC _ Paae 15 2.50 3.00 3.50 Coef. (English) 2.54 2.61 2.61 2.60 2.66 2.70 2.77 2.89 2.88 2.85 3.07 3.20 3.32 #2 Discarded 327.00' 2.000 in/hr Exfiltration over Wetted area Discarded OutFlow Max=0.27 cfs @ 11.85 hrs HW=328.85' (Free Discharge) L2=Exfiltration (Exfiltration Controls 0.27 cfs) Primary OutFlow Max=22.57 cfs @ 11.93 hrs HW=328.90' (Free Discharge) t1= Broad -Crested Rectangular Weir (Weir Controls 22.57 cfs @ 2.50 fps) Summaryfor Pond 3P: SOUTHEASTPOND Inflow Area = 2.747 ac, 69.14% Impervious, Inflow Depth = 2.64" for 50 -YEAR event Inflow = 20.42 cfs @ 11.91 hrs, Volume= 0.604 of Outflow = 4.40 cfs @ 12.11 hrs, Volume= 0.590 af, Atten= 78%, Lag= 12.2 min Primary = 4.40 cfs @ 12.11 hrs, Volume= 0.590 of Routing by Stor-Ind method, Time Span= 5.00-20.00 hrs, dt= 0.05 hrs Starting Elev= 326.00' Surf.Area= 15,936 sf Storage= 22,997 cf Peak Elev= 326.81' @ 12.11 hrs Surf.Area= 18,278 sf Storage= 36,906 cf (13,909 cf above start) Plug -Flow detention time= 334.4 min calculated for 0.062 of (10% of inflow) Center -of -Mass det. time= 61.4 min ( 805.6 - 744.2 ) Volume Invert Avail.Storaae Storage Description #1 321.00' 60,662 cf Custom Stage Data (Prismatic) Listed below (Recalc) Elevation Surf.Area Inc.Store Cum.Store (feet) (so -ft) (cubic -feet) (cubic -feet) 321.00 0 0 0 322.00 126 63 63 323.00 3,274 1,700 1,763 324.00 4,859 4,067 5,830 325.00 6,770 5,815 11,644 326.00 15,936 11,353 22,997 327.00 18,817 17,377 40,374 328.00 21,760 20,289 60,662 Device Routino Invert Outlet Devices #1 Primary 327.30' 1.0' long Sharp -Crested Rectangular Weir 2 End Contraction(s) #2 Primary 326.00' 2.0' long Sharp -Crested Rectangular Weir 2 End Contraction(s) Primary OutFlow Max=4.39 cfs @ 12.11 hrs HW=326.81' (Free Discharge) �__1=Sharp-Crested Rectangular Weir ( Controls 0.00 cfs) 2=Sharp-Crested Rectangular Weir (Weir Controls 4.39 cfs @ 2.95 fps) 47561 GARVEYKIA - proposed Type 1124 -hr 50 -YEAR Rainfall=5.20" Prepared by NACE ENGINEERING, P.C. Printed 4/11/2015 HvdroCADO 9.10 s/n 03732 © 2010 HvdroCAD Software Solutions LLC Pane 16 Summary for Pond 4P: NORTHWESTPOND Inflow Area = 3.641 ac, 46.23% Impervious, Inflow Depth > 2.40" for 50 -YEAR event Inflow = 24.60 cfs @ 11.93 hrs, Volume= 0.728 of Outflow = 3.68 cfs @ 12.16 hrs, Volume= 0.692 af, Atten= 85%, Lag= 13.5 min Primary = 3.68 cfs @ 12.16 hrs, Volume= 0.692 of Routing by Stor-Ind method, Time Span= 5.00-20.00 hrs, dt= 0.05 hrs Starting Elev= 326.00' Surf.Area= 15,478 sf Storage= 28,672 cf Peak Elev= 327.02' @ 12.16 hrs Surf.Area= 17,648 sf Storage= 45,520 cf (16,848 cf above start) Plug -Flow detention time= 432.8 min calculated for 0.034 of (5% of inflow) Center -of -Mass det. time= 74.6 min ( 830.9 - 756.3 ) Volume Invert Avail.Storaae Storaae Description #1 321.00' 63,921 cf Custom Stage Data (Prismatic) Listed below (Recalc) Elevation Surf.Area Inc.Store Cum.Store (feet) (sa-ft) (cubic -feet) (cubic -feet) 321.00 0 0 0 322.00 190 95 95 323.00 5,341 2,766 2,861 324.00 6,879 6,110 8,971 325.00 8,523 7,701 16,672 326.00 15,478 12,001 28,672 327.00 17,610 16,544 45,216 328.00 19,800 18,705 63,921 Device Routina Invert Outlet Devices #1 Primary 327.30' 1.0' long Sharp -Crested Rectangular Weir 2 End Contraction (s) #2 Primary 326.00' 1.3' long Sharp -Crested Rectangular Weir 2 End Contraction(s) Primary OutFlow Max=3.68 cfs @ 12.16 hrs HW=327.02' (Free Discharge) �__1=Sharp-Crested Rectangular Weir ( Controls 0.00 cfs) 2=Sharp-Crested Rectangular Weir (Weir Controls 3.68 cfs @ 3.30 fps) P 11. PORT HvdroCAD RESULTS PRE & POST DEVELOPED CONDITIONS 100 -YEAR DESIGN STORM 47561 GARVEYKIA - exist Type// 24 -hr 100 -YEAR Rainfall=6.50" Prepared by NACE ENGINEERING, P.C. Printed 4/11/2015 HydroCADO 9.10 s/n 03732 © 2010 H; droCAD Software Solutions LLC Paoe 4 Summaryfor Subcatchment1 S: DRAINAGETO NORTHWEST Runoff = 6.01 cfs @ 12.45 hrs, Volume= 0.780 af, Depth= 3.51" Runoff by SCS TR -20 method, UH=SCS, Time Span= 0.00-30.00 hrs, dt= 0.05 hrs Type II 24 -hr 100 -YEAR Rainfall=6.50" Area (sf) CN Description 116.237 73 Woods. Fair. HSG C 116,237 100.00% Pervious Area Tc Length Slope Velocity Capacity Description (min) (feet) (ft/ft) (ft/sec) (cfs) 39.5 100 0.0250 0.04 Sheet Flow, ACROSS GROUND Woods: Dense underbrush n= 0.800 P2= 2.40" 6.7 320 0.0250 0.79 Shallow Concentrated Flow, ACROSS GROUND Woodland Kv= 5.0 fps 46.2 420 Total Summaryfor Subcatchment2S: DRAINAGETO SOUTHEAST Runoff = 9.72 cfs @ 12.33 hrs, Volume= 1.087 af, Depth= 3.51" Runoff by SCS TR -20 method, UH=SCS, Time Span= 0.00-30.00 hrs, dt= 0.05 hrs Type II 24 -hr 100 -YEAR Rainfall=6.50" Area (sf) CN Description 161.995 73 Woods, Fair, HSG C 161,995 100.00% Pervious Area Tc Length Slope Velocity Capacity Description (min) (feet) (ft/ft) (ft/sec) (cfs) 31.8 100 0.0430 0.05 Sheet Flow, ACROSS GROUND Woods: Dense underbrush n= 0.800 P2= 2.40" 5.5 340 0.0430 1.04 Shallow Concentrated Flow, ACROSS GROUND Woodland Kv= 5.0 fr)s 37.3 440 Total 47561 GARVEYKIA - proposed Type// 24 -hr 100 -YEAR Rainfall=6.50" Prepared by NACE ENGINEERING, P.C. Printed 4/11/2015 HvdroCADO 9.10 s/n 03732 © 2010 HvdroCAD Software Solutions LLC Paae 17 Time span=5.00-20.00 hrs, dt=0.05 hrs, 301 points Runoff by SCS TR -20 method, UH=SCS Reach routing by Stor-Ind+Trans method - Pond routing by Stor-Ind method Subcatchment 1S: NORTHWEST Runoff Area=1 19,639 sf 69.14% Impervious Runoff Depth>5.11" Flow Length=200' Slope=0.0200 '/' Tc=2.0 min CN=91 Runoff=25.59 cfs 1.169 of Subcatchment 2S: SOUTHEAST Runoff Area=158,592 sf 46.23% Impervious Runoff Depth>4.48" Flow Length=130' Slope=0.0200 '/' Tc=1.6 min CN=85 Runoff=31.75 cfs 1.359 of Pond 1P: VEGETATED SWALE Peak EIev=329.00' Storage=5,774 cf Inflow=25.59 cfs 1.169 of Discarded=0.27 cfs 0.234 of Primary=25.99 cfs 0.859 of Outflow=26.26 cfs 1.093 of Pond 2P: VEGETATED SWALE Peak Elev=329.17' Storage=5,774 cf Inflow=31.75 cfs 1.359 of Discarded=0.27 cfs 0.224 of Primary=34.06 cfs 1.058 of Outflow=34.33 cfs 1.282 of Pond 3P: SOUTHEAST POND Peak EIev=327.07' Storage=41,618 cf Inflow=25.99 cfs 0.859 of Outflow=6.43 cfs 0.837 of Pond 4P: NORTHWEST POND Peak EIev=327.41' Storage=52,542 cf Inflow=34.06 cfs 1.058 of Outflow=5.67 cfs 1.010 of Total Runoff Area = 6.387 ac Runoff Volume = 2.527 of Average Runoff Depth = 4.75" 43.92% Pervious = 2.805 ac 56.08% Impervious = 3.582 ac 47561 GARVEYKIA -proposed Type// 24 -hr 100 -YEAR Rainfall=6.50" Prepared by NACE ENGINEERING, P.C. Printed 4/11/2015 HvdroCADO 9.10 s/n 03732 © 2010 HydroCAD Software Solutions LLC Paae 18 Summaryfor Subcatchment1S: NORTHWEST PORTION OF SITE Runoff = 25.59 cfs @ 11.91 hrs, Volume= 1.169 af, Depth> 5.11" Runoff by SCS TR -20 method, UH=SCS, Time Span= 5.00-20.00 hrs, dt= 0.05 hrs Type II 24 -hr 100 -YEAR Rainfall=6.50" Area (sf) CN Description " 8,923 98 ROOF 73,794 98 PAVEMENT 36.922 74 >75% Grass cover. Good. HSG C 119,639 91 Weighted Average 36,922 30.86% Pervious Area 82,717 Smooth surfaces n= 0.011 P2= 2.40" 69.14% Impervious Area Tc Length Slope Velocity Capacity Description (min) (feet) (ft/ft) (ft/sec) (cfs) 1.4 100 0.0200 1.19 Sheet Flow, ACROSS PAVEMENT Smooth surfaces n= 0.011 P2= 2.40" 0.6 100 0.0200 2.87 Shallow Concentrated Flow, ACROSS PAVEMENT TO SWALE Paved Kv= 20.3 fps 2.0 200 Total Summaryfor Subcatchment2S: SOUTHEAST PORTION OF SITE Runoff = 31.75 cfs @ 11.91 hrs, Volume= 1.359 af, Depth> 4.48" Runoff by SCS TR -20 method, UH=SCS, Time Span= 5.00-20.00 hrs, dt= 0.05 hrs Type II 24 -hr 100 -YEAR Rainfall=6.50" Area (sf) CN Description 9,123 98 ROOF 64,197 98 PAVEMENT 85.272 74 >75% Grass cover. Good. HSG C 158,592 85 Weighted Average 85,272 53.77% Pervious Area 73,320 46.23% Impervious Area Tc Length Slope Velocity Capacity Description (min) (feet) (ft/ft) (ft/sec) (cfs) 1.4 100 0.0200 1.19 Sheet Flow, ACROSS PAVEMENT Smooth surfaces n= 0.011 P2= 2.40" 0.2 30 0.0200 2.87 Shallow Concentrated Flow, ACROSS PAVEMENT TO SWALE Paved Kv= 20.3 fps 1.6 130 Total 47561 GARVEY KIA - proposed Type// 24 -hr 100 -YEAR Rainfall=6.50" Prepared by NACE ENGINEERING, P.C. Printed 4/11/2015 N ,dE oCAD,9, 9.10 s/n 03732 © 2010 Hy droCAD Software Solutions LLC Page 19 Summaryfor Pond 1 P: VEGETATEDSWALE Inflow Area = 2.747 ac, Inflow = 25.59 cfs @ Outflow = 26.26 cfs @ Discarded = 0.27 cfs @ Primary = 25.99 cfs @ 69.14% Impervious, Inflow Depth > 5.11" 11.91 hrs, Volume= 1.169 of 11.93 hrs, Volume= 1.093 af, 11.80 hrs, Volume= 0.234 of 11.93 hrs, Volume= 0.859 of for 100 -YEAR event Atten= 0%, Lag= 0.8 min Routing by Stor-Ind method, Time Span= 5.00-20.00 hrs, dt= 0.05 hrs Peak Elev= 329.00'@ 11.93 hrs Surf.Area= 5,726 sf Storage= 5,774 cf Plug -Flow detention time= 42.0 min calculated for 1.090 of (93% of inflow) Center -of -Mass det. time= 17.6 min ( 759.9 - 742.2 ) Volume Invert Avail.Storaae Storage Description #1 327.00' 5,774 cf 5.00'W x 400.00'L x 1.50'H Prismatoid Z=3.0 Device Routina Invert Outlet Devices #1 Primary 328.00' 10.0' long x 2.0' 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 Coef. (English) 2.54 2.61 2.61 2.60 2.66 2.70 2.77 2.89 2.88 2.85 3.07 3.20 3.32 #2 Discarded 327.00' 2.000 in/hr Exfiltration over Wetted area Discarded OutFlow Max=0.27 cfs @ 11.80 hrs HW=328.61' (Free Discharge) t2=Exfiltration (Exfiltration Controls 0.27 cfs) Primary OutFlow Max=24.15 cfs @ 11.93 hrs HW=328.94' (Free Discharge) t1=Broad-Crested Rectangular Weir (Weir Controls 24.15 cfs @ 2.56 fps) Summaryfor Pond 2P: VEGETATEDSWALE Inflow Area = 3.641 ac, 46.23% Impervious, Inflow = 31.75 cfs @ 11.91 hrs, Volume Outflow = 34.33 cfs @ 11.90 hrs, Volume Discarded = 0.27 cfs @ 11.80 hrs, Volume Primary = 34.06 cfs @ 11.90 hrs, Volume Inflow Depth > 4.48" 1.359 of 1.282 af, 0.224 of = 1.058 of for 100 -YEAR event Atten= 0%, Lag= 0.0 min Routing by Stor-Ind method, Time Span= 5.00-20.00 hrs, dt= 0.05 hrs Peak Elev= 329.17'@ 11.90 hrs Surf.Area= 5,726 sf Storage= 5,774 cf Plug -Flow detention time= 35.5 min calculated for 1.282 of (94% of inflow) Center -of -Mass det. time= 13.8 min ( 769.6 - 755.8 ) Volume Invert Avail.Storaae Storage Description #1 327.00' 5,774 cf 5.00'W x 400.001 x 1.50'H Prismatoid Z=3.0 Device Routina Invert Outlet Devices #1 Primary 328.00' 10.0' long x 2.0' 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 47561 GARVEYKIA - proposed Type// 24 -hr 100 -YEAR Rainfall=6.50" Prepared by NACE ENGINEERING, P.C. Printed 4/11/2015 HvdroCAD® 9.10 s/n 03732 © 2010 HvdroCAD Software Solutions LLC Page gn 2.50 3.00 3.50 Coef. (English) 2.54 2.61 2.61 2.60 2.66 2.70 2.77 2.89 2.88 2.85 3.07 3.20 3.32 #2 Discarded 327.00' 2.000 in/hr Exfiltration over Wetted area Discarded OutFlow Max=0.27 cfs @ 11.80 hrs HW=328.82' (Free Discharge) L2=Exfiltration (Exfiltration Controls 0.27 cfs) Primary OutFlow Max=33.23 cfs @ 11.90 hrs HW=329.15' (Free Discharge) L1=Broad-Crested Rectangular Weir (Weir Controls 33.23 cfs @ 2.89 fps) Summaryfor Pond 3P: SOUTHEASTPOND Inflow Area = 2.747 ac, 69.14% Impervious, Inflow Depth > 3.75" for 100 -YEAR event Inflow = 25.99 cfs @ 11.93 hrs, Volume= 0.859 of Outflow = 6.43 cfs @ 12.08 hrs, Volume= 0.837 af, Atten= 75%, Lag= 9.2 min Primary = 6.43 cfs @ 12.08 hrs, Volume= 0.837 of Routing by Stor-Ind method, Time Span= 5.00-20.00 hrs, dt= 0.05 hrs Starting Elev= 326.00' Surf.Area= 15,936 sf Storage= 22,997 cf Peak Elev= 327.07' @ 12.08 hrs Surf.Area= 19,011 sf Storage= 41,618 cf (18,621 cf above start) Plug -Flow detention time= 203.3 min calculated for 0.309 of (36% of inflow) Center -of -Mass det. time= 55.0 min ( 802.7 - 747.6 ) Volume Invert Avail.Storage Storage Description #1 321.00' 60,662 cf Custom Stage Data (Prismatic) Listed below (Recalc) Elevation Surf.Area Inc.Store Cum.Store (feet) (sa-ft) (cubic -feet) (cubic -feet) 321.00 0 0 0 322.00 126 63 63 323,00 3,274 1,700 1,763 324.00 4,859 4,067 5,830 325.00 6,770 5,815 11,644 326.00 15,936 11,353 22,997 327.00 18,817 17,377 40,374 328.00 21,760 20,289 60,662 Device Routina Invert Outlet Devices #1 Primary 327.30' 1.0' long Sharp -Crested Rectangular Weir 2 End Contraction (s) #2 Primary 326.00' 2.0' long Sharp -Crested Rectangular Weir 2 End Contraction(s) Primary OutFlow Max=6.41 cfs @ 12.08 hrs HW=327.06' (Free Discharge) �__1=Sharp-Crested Rectangular Weir ( Controls 0.00 cfs) 2=Sharp-Crested Rectangular Weir (Weir Controls 6.41 cfs @ 3.37 fps) 47561 GARVEYKIA - proposed Type // 24 -hr 100 -YEAR Rainfall=6.50" Prepared by NACE ENGINEERING, P.C. Printed 4/11/2015 HvdroCAD® 9.10 s/n 03732 © 2010 HvdroCAD Software Solutions LLC Paae 21 Summaryfor Pond 4P: NORTHWESTPOND Inflow Area = 3.641 ac, 46.23% Impervious, Inflow Depth > 3.49" for 100 -YEAR event Inflow = 34.06 cfs @ 11.90 hrs, Volume= 1.058 of Outflow = 5.67 cfs @ 12.09 hrs, Volume= 1.010 af, Atten= 83%, Lag= 11.3 min Primary = 5.67 cfs @ 12.09 hrs, Volume= 1.010 of Routing by Stor-Ind method, Time Span= 5.00-20.00 hrs, dt= 0.05 hrs Starting Elev= 326.00' Surf.Area= 15,478 sf Storage= 28,672 cf Peak Elev= 327.41' @ 12.09 hrs Surf.Area= 18,499 sf Storage= 52,542 cf (23,870 cf above start) Plug -Flow detention time= 247.3 min calculated for 0.352 of (33% of inflow) Center -of -Mass det. time= 68.3 min ( 826.3 - 758.0 ) Volume Invert Avail.Storaae Storage Description #1 321.00' 63,921 cf Custom Stage Data (Prismatic) Listed below (Recalc) Elevation Surf.Area Inc.Store Cum.Store (feet) (sa-ft) (cubic -feet) (cubic -feet) 321.00 0 0 0 322.00 190 95 95 323.00 5,341 2,766 2,861 324.00 6,879 6,110 8,971 325.00 8,523 7,701 16,672 326.00 15,478 12,001 28,672 327.00 17,610 16,544 45,216 328.00 19,800 18,705 63,921 Device Routinq Invert Outlet Devices #1 Primary 327.30' 1.0' long Sharp -Crested Rectangular Weir 2 End Contraction(s) #2 Primary 326.00' 1.3' long Sharp -Crested Rectangular Weir 2 End Contraction(s) Primary OutFlow Max=5.66 cfs @ 12.09 hrs HW=327.40' (Free Discharge) 1:1=Sharp-Crested Rectangular Weir (Weir Controls 0.11 cfs @ 1.06 fps) 2=Sharp-Crested Rectangular Weir (Weir Controls 5.55 cfs @ 3.88 fps)