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A-1 Treeworks - SWM - compiled STORMWATER MANAGEMENT SYSTEM ENGINEERING REPORT For New Facility Town of Queensbury, Warren County Queensbury, New York Prepared For: A-1 Treeworks, LLC 308-310 Corinth Road Queensbury, New York 12804 Prepared By: Kevin L. Hastings, P.E. Consulting Engineers Mailing address: 3 Jackson Avenue South Glens Falls,New York 12803 Tel: 518-222-1338 Fax: 518-747-2166 March 10, 2017 General The proposed development of a new storage building will have extremely low impact on the drainage characteristics of the site. There will be substantial clearing of the existing vegetation and woods, as necessary for the construction of the proposed storage building, gravel driveways, material storage areas, and lawns. The stormwater management system for the proposed site improvements will be designed to comply with the Code of the Town of Queensbury, specifically Chapter 147 Stormwater Management and section 179-6-080 Stormwater Runoff, and the New York State Department of Environmental Conservation (NYSDEC) stormwater management design manual, as applicable. The post-development peak runoff rate will be attenuated to be equal to or less than the pre- development conditions for a 50-year design storm. To satisfy requirements of the NYSDEC design manual, this report also includes analysis of the 1-year, 10-year, and 100-year design storms for possible mitigation. The existing drainage patterns shall be maintained in all locations on the project. There will be no massive excavation or engineered embankment fills on the site, or other significant structures for drainage purposes. The runoff management system will use a minimum of man-made structures, and where feasible, incorporate "green"infrastructure. The drainage analysis will be prepared in accordance with current hydrology practice in studying the watershed. The storm water runoff calculations to be conducted using the method prescribed in the USDA Soil Conservation Service Technical Release No. 20. The software program for predictive modeling is the HydroCad Stormwater Modeling System (version 10.00) produced by HydroCAD Software Solutions, LLC of Chocurua, New Hampshire. All of the studied events will be 24-hour duration, all SCS Type II events. Stormwater Management System Page I New Storage Building, Queensbury NY The NRCS Web Soil Survey of Warren County indicates a single map unit, the Oakville series. Oakville is described as a "loamy fine sand" with 0-8 percent slopes, well drained, and very rapid permeability. The Oakville unit is classified as HSG "A" soils. See Appendix C for the NRCS Web soils map and series classifications. The field report of the deep hole test pits was consistent with the Oakville series description. Two (2) test holes were excavated to a depth of six (6) feet, with no ledge rock or evidence of groundwater mottling. The percolation rate assessment was less than (1) minute per inch. Additional field testing will be performed at the time of construction to verify the depths of the soil profile and seasonal high groundwater in relationship to the proposed infiltration practices. The descriptions of the various land coverage in the HydroCad model were selected based on the soils group (Hydrologic Soil Group) "A", and where applicable the runoff characteristic of "good"—"fair" - "poor". The weighted runoff values selected from the SCS curve number chart were the following: 98 Roofs,paved driveway 43 Woods/grass, fair, HSG A 39 Lawn(re-vegetated), >75% grass cover, good, HSG A The newest resource for New York State climatology data is available from the Northeast Regional Climate Center at the Cornell University web site. This database has incorporated the extreme weather events of recent history, and more importantly the regional changes in climatology to update the 1960's atlas TP-40. The "Extreme Precipitation in New York& New England" interactive web tool (web site: http://precip.eas.comell.edu/ ), can generate a rainfall table of values for this specific geographic location (N 43.298, W 73.692). The 24-hour storm intensity values to be used in the modeling & analysis portion of the design report, as follows: Stormwater Management System Page 2 New Storage Building, Queensbury NY Extreme Precipitation Tables: 43.298°N, 73.692°W Page 1 of 1 Extreme Precipitation Tables Northeast Regional Climate Center Data represents point estimates calculated from partial duration series.All precipitation amounts are displayed in inches. Smoothing Yes State New York Location Longitude 73.692 degrees West Latitude 43.298 degrees North Elevation 0 feet Date/Time Tue,14 Feb 2017 16:06:54-0500 Extreme Precipitation Estimates 5min 10min 15min 30min 60min 120min lhr 2hr 3hr 6hr 12hr 24hr 48hr lday 2day 4day 7day 10day lyr 0.27 0.42 0.52 0.68 0.85 1.06 lyr 0.73 0.96 1.21 1.49 1.82 2.22 2.49 lyr 1.96 2.39 2.81 3.37 3.93 lyr 2yr 0.33 0.50 0.62 0.82 1.03 1.28 2yr 0.89 1.14 1.46 1.78 2.15 2.57 2.90 2yr 2.28 2.79 3.23 3.89 4.41 2yr 5yr 0.39 0.60 0.75 1.01 1.29 1.61 5yr 1.11 1.42 1.84 2.22 2.66 3.15 3.55 5yr 2.79 3.42 3.92 4.59 5.20 5yr 10yr 0.43 0.68 0.86 1.17 1.52 1.91 10yr 1.31 1.67 2.18 2.63 3.12 3.66 4.15 10yr 3.24 3.99 4.54 5.21 5.89 10yr 25yr 0.51 0.81 1.03 1.42 1.89 2.38 25yr 1.63 2.08 2.73 3.27 3.86 4.48 5.09 25yr 3.97 4.90 5.51 6.17 6.96 25yr. 50yr 0.57 0.92 1.18 1.65 2.24 2.84 50yr 1.93 2.45 3.25 3.88 4.55 5.23 5.95 50yr 4.63 5.72 6.38 7.01 7.89 50yr 100yr 0.66 1.06 1.37 1.94 2.64 3.36 100yr 2.28 2.89 3.84 4.58 5.33 6.10 6.95 100yr 5.40 6.68 7.40 7.97 8.95 100yr 200yr 0.74 1.21 1.57 2.26 3.12 3.99 200yr 2.70 3.41 4.56 5.42 6.27 7.11 8.12 200yr 6.30 7.81 8.58 9.06 10.15 200yr 500yr,0.90 1.48 1.92 2.79 3.90 4.99 500yr 3.37 4.25 5.70 6.74 7.75 8.73 9.98 500yr 7.73 9.59 10.44 10.74 12.00 500yr Lower Confidence Limits 5min 10min 15min 30min 60min 120min lhr 2hr 3hr 6hr 12hr 24hr 48hr lday 2day 4day 7day 10day lyr 0.23 0.36 0.44 0.59 0.72 0.80 lyr 0.62 0.79 0.96 1.19 1.67 2.03 2.25 lyr 1.80 2.17 2.53 3.00 3.55 lyr 2yr 0.31 0.48 0.59 0.80 0.98 1.14 2yr 0.85 1.12 1.27 1.64 2.07 2.51 2.84 2yr 2.23 2.73 3.16 3.79 4.32 2yr 5yr 0.36 0.55 0.68 0.94 1.19 1.34 5yr 1.03 1.31 1.50 1.91 2.41 2.96 3.33 5yr 2.62 3.20 3.67 4.33 4.91 5yr 10yr 0.39 0.60 0.75 1.05 1.35 1.52 10yr 1.17 1.49 1.70 2.13 2.68 3.34 3.74 10yr 2.95 3.60 4.08 4.75 5.39 10yr 25yr 0.45 0.69 0.86 1.23 1.62 1.80 25yr 1.40 1.76 2.01 2.47 3.10 3.89 4.36 25yr 3.44 4.20 4.68 5.37 6.09 25yr 50yr 0.50 0.77 0.95 1.37 1.85 2.02 50yr 1.59 1.98 2.25 2.74 3.46 4.38 4.89 50yr 3.87 4.70 5.19 5.87 6.67 50yr 100yr 0.56 0.85 1.07 1.54 2.11 2.29 100yr 1.82 2.24 2.54 3.06 3.86 4.93 5.49 100yr 4.36 5.28 5.73 6.43 7.32 100yr 200yr 0.63 0.95 1.20 1.74 2.42 2.59 200yr 2.09 2.53 2.85 3.42 4.31 5.57 6.16 200yr 4.93 5.92 6.31 7.06 8.02 200yr 500yr.0.74 1.10 1.41 2.05 2.91 3.06 500yr 2.51 2.99 3.34 3.94 4.98 6.53 7.16 500yr 5.78 6.88 7.17 7.97 1 9.04 500yr Upper Confidence Limits 5min 10min 15min 30min 60min 120min lhr 2hr 3hr 6hr 12hr 24hr 48hr lday 2day May 7day 10day lyr 0.30 0.47 0.57 0.76 0.94 1.07 lyr 0.81 1.05 1.201.55 1.96 2.37 2.68 lyr 2.10 2.58 3.04 3.58 4.18 lyr 2yr 0.34 0.53 0.65 0.88 1.08 1.21 2yr 0.93 1.19 1.36 1.74 2.19 2.65 3.00 2yr 2.35 2.89 3.35 4.01 4.53 2yr 5yr 0.41 0.64 0.79 1.09 1.39 1.56 5yr 1.20 1.53 1.74 2.19 2.71 3.35 3.79 5yr 2.96 3.65 4.19 4.88 5.49 5yr 10yr 0.49 0.76 0.94 1.31 1.69 1.90 10yr 1.46 1.86 2.12 2.62 3.20 4.01 4.56 10yr 3.55 4.39 4.99 5.71 6.37 10yr 25yr 0.62 0.95 1.18 1.68 2.21 2.46 25yr 1.91 2.40 2.88 3.34 4.01 5.07 5.82 25yr 4.49 5.60 6.31 7.04 7.77 25yr 50yr 0.74 1.12 1.40 2.01 2.70 3.00 50yr 2.33 2.93 3.34 4.01 4.76 6.08 7.02 50yr 5.38 6.75 7.55 8.27 9.04 50yr 100yr 0.88 1.33 1.66 2.40 3.30 3.64 100yr 2.85 3.56 4.07 4.82 5.65 7.29 8.44 100yr 6.45 8.12 9.06 9.71 10.51 100yr 200yr 1.05 1.58 2.00 2.90 4.04 4.44 200yr 3.49 4.34 4.96 5.80 6.72 8.75 10.17 200yr 7.74 9.78 10.87 11.40 12.24 200yr 500yr. 1.33 1.98 2.55 3.707527 5.78 500yr 4.55 5.65 6.46 7.41 8.47 11.13 13.03 500yr 9.85 12.53 13.85 14.12 14.99 500yr Aosreredhy CIS Norfheast Regional Climate Cenfer http://precip.eas.comell.edu/data.php91487106416018 2/14/2017 DESIGN STORM TOTAL PRECIPITATION (24 hours) 1-year rainfall (CPv) 2.22 inches 10-year rainfall (Qp) 3.66 inches 50-year rainfall 5.23 inches 100-year rainfall (Qf) 6.10 inches. The HydroCad model calculations of the pre-development runoff from the watershed study area will be used to guide the post-development conditions, with desirable goals to restrict the peak runoff to a level equal to, or less than the pre-development rates. Where required, the total runoff will be managed to pre-development volumes. Methodolo2y The storm water modeling computations will be conducted using the USDA Soil Conservation Technical Release No. 20 (TR-20) methods in the HydroCad computer software. This software is widely used in hydrological studies, stormwater modeling & analysis, and comprehensive hydraulic designs. The manual input of the land characteristics and other features of the site has been meticulous, ensuring a thorough knowledge of the site conditions. This careful attention to site information will become the reliable basis of the computerized analysis. The methodology is comparable in accuracy to tabular methods (i.e. TR-55, rational method, etc.) formerly used in watershed analysis. The HydroCad analysis will utilize several "design point"nodes in the report. Runoff hydrology is a dynamic, time based discharge curve with peak flows that may or not coincide. The use of a design point serves as a durable reference within the HydroCad model to totalize the various runoff values into a single time-weighted hydrograph. Hydrograph output values can be later compared on equal basis to help determine system compliance. Stormwater Management System Page 3 New Storage Building, Queensbury NY The design criteria for this report, as follows: • Evaluate the "pre" and"post" development conditions using the SCS 24-hour Type II rainfall distribution charts; • Provide detention storage capacity "at the source", as required to manage the additional runoff volume generated by the improvements; • Provide for stabilized soil disturbances and construction phase erosion control measures in accordance with the NYSDEC "Blue Book"; • Provide runoff infiltration using standard NYSDEC practices; • Compliance with the NYSDEC design manual and the Town of Queensbury local law. Hydroloay-Existing Conditions The HydroCad characterization of the watershed study area is known as a "subcatchment". Subcatchments 1, 2, and 3 represent the entire 9.54+/- acre property prior to this proposed development. This "pre-development" study will consider the land features (slopes, distances, area), ground coverage type (woods, lawn, driveway), and soil infiltration capacity. The pre-development runoff "curve number" CN, weighted by area and coverage factors, was 49. This is a benchmark value that can be compared later on as a predictive measure of the hydrological change in the watershed due to the proposed development. The pre-development impervious area consists mainly of existing roofs and asphalt driveways, as 58,995+/- square feet. The flow of runoff through a property is dynamic, a time based measurement. The "time of concentration" Tc is the estimated time for 100% runoff contribution from the entire site. On this site the Tc paths were identified for each subcatchment. The Tc values ranged from 37.3 minutes up to 90.0 minutes. Stormwater Management System Page 4 New Storage Building, Queensbury NY The pre-development peak runoff rates and total volumes are summarized from the HydroCad report for each design point as follows: DP-1 PEAK TOTAL RUNOFF RATE VOLUME 1-year 0.19 cfs ** 0.051 acre-feet 10-year 1.43 cfs ** 0.215 acre-feet 50-year 3.52 cfs 0.465 acre-feet 100-year 4.85 cfs ** 0.623 acre-feet DP-2 PEAK TOTAL RUNOFF RATE VOLUME 1-year 0.00 cfs ** 0.000 acre-feet 10-year 0.01 cfs ** 0.006 acre-feet 50-year 0.16 cfs 0.063 acre-feet 100-year 0.46 cfs ** 0.116 acre-feet DP-3 PEAK TOTAL RUNOFF RATE VOLUME 1-year 0.00 cfs ** 0.000 acre-feet 10-year 0.03 cfs ** 0.023 acre-feet 50-year 0.31 cfs 0.134 acre-feet 100-year 0.65 cfs ** 0.227 acre-feet ** NYSDEC Stormwater Design Manual See Appendix A for the watershed map SC-1 and the HydroCad calculations report. Hydrolou - Proposed Conditions The proposed storage building, driveways, material storage areas, and re-vegetated lawn areas will have a minimal impact on the drainage characteristics of the watershed. The use of Stormwater Management System Page 5 New Storage Building, Queensbury NY infiltration practices will provide immediate recharge "at the source". This immediate management of impervious runoff at the source will also serve to attenuate the post-development flows, provide function for water quality treatment (WQv), and provide in-ground detention of the channel protection volume (CPv). The gravel driveways will be super-elevated at the perimeter to collect runoff into the detention basin at a low point. The stormwater will then be routed through a deep sump catch basin before passing into the stone infiltration bed (drainage system "A") for groundwater recharge. The connected roof areas will also flow to the respective drainage systems through vegetated swales. The proposed total area of soil disturbance is estimated to be 210,200+/- square feet (roughly 810' x 260'). The proposed impervious area (roofs, driveways) will be 153,202+/- square feet, representing 36.9 percent of the 9.54+/- acre study area. This aggregate total can then be broken down into its components. The new roof area will be 15,000 square feet, and gravel driveways & material storage areas at 79,207 square feet. All of the pre-development impervious roofs and asphalt driveways (58,995+/- square feet)will remain in the post-development condition. The post-development composite SCS runoff curve number will be 61. The change in hydrology due to the site improvements is considered significant and volume detention basin(s) will be required to mitigate the runoff. For comparison, the post-development peak runoff rates and total volumes are summarized from the HydroCad report for each design point as follows: DP-1 PEAK TOTAL RUNOFF RATE VOLUME 1-year 0.00 cfs ** 0.000 acre-feet 10-year 0.00 cfs ** 0.000 acre-feet 50-year 2.41 cfs 0.089 acre-feet 100-year 4.55 cfs ** 0.197 acre-feet Stormwater Management System Page 6 New Storage Building, Queensbury NY DP-2 PEAK TOTAL RUNOFF RATE VOLUME 1-year 0.00 cfs ** 0.000 acre-feet 10-year 0.00 cfs ** 0.000 acre-feet 50-year 0.00 cfs 0.000 acre-feet 100-year 0.00 cfs ** 0.000 acre-feet DP-3 PEAK TOTAL RUNOFF RATE VOLUME 1-year 0.00 cfs ** 0.000 acre-feet 10-year 0.00 cfs ** 0.000 acre-feet 50-year 0.00 cfs 0.000 acre-feet 100-year 0.00 cfs ** 0.000 acre-feet ** NYSDEC Stormwater Design Manual See Appendix B for the watershed map SC-2 and the HydroCad calculations report. The water quality volume (WQv) requirement was calculated for each one of the stormwater management practices having impervious coverage. Also, the channel protection volume (CPv) can be collected from the HydroCad report for the 1-year analysis. NYSDEC GP-0-15-001 Permit This site will be covered by a SPDES general permit to discharge stormwater from a construction site. The limits of disturbance is 4.82+/- acres. Therefore the preparation of a Stormwater Pollution Prevention Plan (SWPPP) is required by NYSDEC. Stormwater Management System Page 7 New Storage Building, Queensbury NY Erosion & Sediment Control All work related to the construction of the new storage building, driveway, material storage & parking areas, etc. shall conform to the "New York State Guidelines for Urban Erosion and Sedimentation Control" (i.e. Blue Book). The perimeter down slope areas will be protected with a continuous silt fence as temporary sediment control. The seed stabilization of all exposed soils will be completed as the work progresses. Permanent turf seeding will occur within 14 days of finish grading. Other measures which are considered "best management practice" include: stabilized construction entrance, and inlet protection. Green Infrastructure In review of Chapter 5 of the NYSDEC design manual, the following "green" practices will be incorporated into this site development: 1. Preservation of Undisturbed Areas —more than 10% of the site will remain undeveloped and undisturbed, and conserve the existing wooded area. 2. Reduction of Clearing and Grading—all of the site improvements will be clustered in one vicinity, and with minimal clearing of existing vegetation. 3. Disconnection of rooftop runoff areas. 4. Tree planting. Other infrastructure practices such as porous pavement,rain gardens, green roof, and rain barrels were either cost prohibitive OR not practical in the context of a self-storage facility. Stormwater Management System Page 8 New Storage Building, Queensbury NY Conclusion: Based on the hydrological modeling of the watershed, and professional analysis of the HydroCad results, we have determined the proposed stormwater management systems will function to attenuate the peak runoff rate and volumes as required by NYSDEC and Town of Queensbury local law. The proposed stormwater management systems, as designed will not adversely affect the watershed hydrology. Stormwater Management System Page 9 New Storage Building, Queensbury NY Appendix A Pre-Development Conditions Subcatchment Map SC-1 HydroCad Drainage Diagram HydroCad Analysis Report 1rro5 drvim do do "I'll 11 .—Ppv 6..j..A "U dsm'�Nnoa avou mimmoo of -s DIVII s v —NINI—41" -1...16-3 6.,�I�...D a a M �\ o a O J � FI p 'VIA3.V CQ CORINTHROAD U J N J M 0 U) o C: CI o }, oN o co O N 0 - U)CL C'7 y ' cin .O � aC) Y LU o d � o c� O 4 2 a -J E ° QC) � . Ea _ NmYU) 4-+ L >,M r o 6 a) o N � c- CD a Q® O oa < N � r � U Y � J c 0 r � U �O CLf6 Q U 7 W A-1 Treeworks - existing conditions Type // 24-hr 1-yr Rainfall=2.22" Prepared by Kevin L. Hastings, PE Printed 3/14/2017 HydroCAD® 10.00-19 s/n 02365 @2016 HydroCAD Software Solutions LLC Page 1 Summary for Subcatchment 1S: Subcatchment 1 Runoff = 0.19 cfs @ 12.61 hrs, Volume= 0.051 af, Depth= 0.20" Runoff by SCS TR-20 method, UH=SCS, Weighted-CN, Time Span= 0.00-72.00 hrs, dt= 0.05 hrs Type II 24-hr 1-yr Rainfall=2.22" Area (sf) CN Description 45,679 98 Paved parking, HSG A 7,521 43 Woods/grass comb., Fair, HSG A 13,317 98 Unconnected roofs, HSG A 67,909 39 >75% Grass cover, Good, HSG A 134,426 65 Weighted Average 75,430 56.11% Pervious Area 58,996 43.89% Impervious Area 13,317 22.57% Unconnected Tc Length Slope Velocity Capacity Description (min) (feet) (ft/ft) (ft/sec) (cfs) 41.3 300 0.0166 0.12 Sheet Flow, Lawn Grass: Dense n= 0.240 P2= 2.57" 2.0 175 0.0050 1.44 Shallow Concentrated Flow, Driveway Paved Kv= 20.3 fps 43.3 475 Total Summary for Subcatchment 2S: Subcatchment 2 Runoff = 0.00 cfs @ 0.00 hrs, Volume= 0.000 af, Depth= 0.00" Runoff by SCS TR-20 method, UH=SCS, Weighted-CN, Time Span= 0.00-72.00 hrs, dt= 0.05 hrs Type II 24-hr 1-yr Rainfall=2.22" Area (sf) CN Description 23,679 43 Woods/grass comb., Fair, HSG A 90,801 39 >75% Grass cover, Good, HSG A 114,480 40 Weighted Average 114,480 100.00% Pervious Area Tc Length Slope Velocity Capacity Description (min) (feet) (ft/ft) (ft/sec) (cfs) 35.1 250 0.0480 0.12 Sheet Flow, Woods Woods: Light underbrush n= 0.400 P2= 2.57" 2.2 150 0.0266 1.14 Shallow Concentrated Flow, Lawn Short Grass Pasture Kv= 7.0 fps 37.3 400 Total A-1 Treeworks - existing conditions Type // 24-hr 1-yr Rainfall=2.22" Prepared by Kevin L. Hastings, PE Printed 3/14/2017 HydroCAD® 10.00-19 s/n 02365 @2016 HydroCAD Software Solutions LLC Page 2 Summary for Subcatchment 3S: Subcatchment 3 Runoff = 0.00 cfs @ 0.00 hrs, Volume= 0.000 af, Depth= 0.00" Runoff by SCS TR-20 method, UH=SCS, Weighted-CN, Time Span= 0.00-72.00 hrs, dt= 0.05 hrs Type II 24-hr 1-yr Rainfall=2.22" Area (sf) CN Description 166,507 43 Woods/grass comb., Fair, HSG A 166,507 100.00% Pervious Area Tc Length Slope Velocity Capacity Description (min) (feet) (ft/ft) (ft/sec) (cfs) 84.0 240 0.0050 0.05 Sheet Flow, Woods Woods: Light underbrush n= 0.400 P2= 2.57" 6.0 190 0.0447 0.53 Shallow Concentrated Flow, Woods Forest w/Heavy Litter Kv= 2.5 fps 90.0 430 Total Summary for Reach DP-1: Design Point 1 Inflow Area = 3.086 ac, 43.89% Impervious, Inflow Depth = 0.20" for 1-yr event Inflow = 0.19 cfs @ 12.61 hrs, Volume= 0.051 of Outflow = 0.19 cfs @ 12.61 hrs, Volume= 0.051 af, Atten= 0%, Lag= 0.0 min Routing by Stor-Ind+Trans method, Time Span= 0.00-72.00 hrs, dt= 0.05 hrs Summary for Reach DP-2: Design Point 2 Inflow Area = 2.628 ac, 0.00% Impervious, Inflow Depth = 0.00" for 1-yr event Inflow = 0.00 cfs @ 0.00 hrs, Volume= 0.000 of Outflow = 0.00 cfs @ 0.00 hrs, Volume= 0.000 af, Atten= 0%, Lag= 0.0 min Routing by Stor-Ind+Trans method, Time Span= 0.00-72.00 hrs, dt= 0.05 hrs Summary for Reach DP-3: Design Point 3 Inflow Area = 3.822 ac, 0.00% Impervious, Inflow Depth = 0.00" for 1-yr event Inflow = 0.00 cfs @ 0.00 hrs, Volume= 0.000 of Outflow = 0.00 cfs @ 0.00 hrs, Volume= 0.000 af, Atten= 0%, Lag= 0.0 min Routing by Stor-Ind+Trans method, Time Span= 0.00-72.00 hrs, dt= 0.05 hrs A-1 Treeworks - existing conditions Type // 24-hr 10-yr Rainfall=3.66" Prepared by Kevin L. Hastings, PE Printed 3/14/2017 HydroCAD® 10.00-19 s/n 02365 @2016 HydroCAD Software Solutions LLC Page 3 Summary for Subcatchment 1S: Subcatchment 1 Runoff = 1.43 cfs @ 12.47 hrs, Volume= 0.215 af, Depth= 0.84" Runoff by SCS TR-20 method, UH=SCS, Weighted-CN, Time Span= 0.00-72.00 hrs, dt= 0.05 hrs Type II 24-hr 10-yr Rainfall=3.66" Area (sf) CN Description 45,679 98 Paved parking, HSG A 7,521 43 Woods/grass comb., Fair, HSG A 13,317 98 Unconnected roofs, HSG A 67,909 39 >75% Grass cover, Good, HSG A 134,426 65 Weighted Average 75,430 56.11% Pervious Area 58,996 43.89% Impervious Area 13,317 22.57% Unconnected Tc Length Slope Velocity Capacity Description (min) (feet) (ft/ft) (ft/sec) (cfs) 41.3 300 0.0166 0.12 Sheet Flow, Lawn Grass: Dense n= 0.240 P2= 2.57" 2.0 175 0.0050 1.44 Shallow Concentrated Flow, Driveway Paved Kv= 20.3 fps 43.3 475 Total Summary for Subcatchment 2S: Subcatchment 2 Runoff = 0.01 cfs @ 24.01 hrs, Volume= 0.006 af, Depth= 0.03" Runoff by SCS TR-20 method, UH=SCS, Weighted-CN, Time Span= 0.00-72.00 hrs, dt= 0.05 hrs Type II 24-hr 10-yr Rainfall=3.66" Area (sf) CN Description 23,679 43 Woods/grass comb., Fair, HSG A 90,801 39 >75% Grass cover, Good, HSG A 114,480 40 Weighted Average 114,480 100.00% Pervious Area Tc Length Slope Velocity Capacity Description (min) (feet) (ft/ft) (ft/sec) (cfs) 35.1 250 0.0480 0.12 Sheet Flow, Woods Woods: Light underbrush n= 0.400 P2= 2.57" 2.2 150 0.0266 1.14 Shallow Concentrated Flow, Lawn Short Grass Pasture Kv= 7.0 fps 37.3 400 Total A-1 Treeworks - existing conditions Type // 24-hr 10-yr Rainfall=3.66" Prepared by Kevin L. Hastings, PE Printed 3/14/2017 HydroCADO 10.00-19 s/n 02365 ©2016 HydroCAD Software Solutions LLC Page 4 Summary for Subcatchment 3S: Subcatchment 3 Runoff = 0.03 cfs @ 16.30 hrs, Volume= 0.023 af, Depth= 0.07" Runoff by SCS TR-20 method, UH=SCS, Weighted-CN, Time Span= 0.00-72.00 hrs, dt= 0.05 hrs Type II 24-hr 10-yr Rainfall=3.66" Area (sf) CN Description 166,507 43 Woods/grass comb., Fair, HSG A 166,507 100.00% Pervious Area Tc Length Slope Velocity Capacity Description (min) (feet) (ft/ft) (ft/sec) (cfs) 84.0 240 0.0050 0.05 Sheet Flow, Woods Woods: Light underbrush n= 0.400 P2= 2.57" 6.0 190 0.0447 0.53 Shallow Concentrated Flow, Woods Forest w/Heavy Litter Kv= 2.5 fps 90.0 430 Total Summary for Reach DP-1: Design Point 1 Inflow Area = 3.086 ac, 43.89% Impervious, Inflow Depth = 0.84" for 10-yr event Inflow = 1.43 cfs @ 12.47 hrs, Volume= 0.215 of Outflow = 1.43 cfs @ 12.47 hrs, Volume= 0.215 af, Atten= 0%, Lag= 0.0 min Routing by Stor-Ind+Trans method, Time Span= 0.00-72.00 hrs, dt= 0.05 hrs Summary for Reach DP-2: Design Point 2 Inflow Area = 2.628 ac, 0.00% Impervious, Inflow Depth = 0.03" for 10-yr event Inflow = 0.01 cfs @ 24.01 hrs, Volume= 0.006 of Outflow = 0.01 cfs @ 24.01 hrs, Volume= 0.006 af, Atten= 0%, Lag= 0.0 min Routing by Stor-Ind+Trans method, Time Span= 0.00-72.00 hrs, dt= 0.05 hrs Summary for Reach DP-3: Design Point 3 Inflow Area = 3.822 ac, 0.00% Impervious, Inflow Depth = 0.07" for 10-yr event Inflow = 0.03 cfs @ 16.30 hrs, Volume= 0.023 of Outflow = 0.03 cfs @ 16.30 hrs, Volume= 0.023 af, Atten= 0%, Lag= 0.0 min Routing by Stor-Ind+Trans method, Time Span= 0.00-72.00 hrs, dt= 0.05 hrs A-1 Treeworks - existing conditions Type 11 24-hr 50-yr Rainfall=5.23" Prepared by Kevin L. Hastings, PE Printed 3/14/2017 HydroCAD® 10.00-19 s/n 02365 @2016 HydroCAD Software Solutions LLC Page 5 Summary for Subcatchment 1S: Subcatchment 1 Runoff = 3.52 cfs @ 12.44 hrs, Volume= 0.465 af, Depth= 1.81" Runoff by SCS TR-20 method, UH=SCS, Weighted-CN, Time Span= 0.00-72.00 hrs, dt= 0.05 hrs Type II 24-hr 50-yr Rainfall=5.23" Area (sf) CN Description 45,679 98 Paved parking, HSG A 7,521 43 Woods/grass comb., Fair, HSG A 13,317 98 Unconnected roofs, HSG A 67,909 39 >75% Grass cover, Good, HSG A 134,426 65 Weighted Average 75,430 56.11% Pervious Area 58,996 43.89% Impervious Area 13,317 22.57% Unconnected Tc Length Slope Velocity Capacity Description (min) (feet) (ft/ft) (ft/sec) (cfs) 41.3 300 0.0166 0.12 Sheet Flow, Lawn Grass: Dense n= 0.240 P2= 2.57" 2.0 175 0.0050 1.44 Shallow Concentrated Flow, Driveway Paved Kv= 20.3 fps 43.3 475 Total Summary for Subcatchment 2S: Subcatchment 2 Runoff = 0.16 cfs @ 12.66 hrs, Volume= 0.063 af, Depth= 0.29" Runoff by SCS TR-20 method, UH=SCS, Weighted-CN, Time Span= 0.00-72.00 hrs, dt= 0.05 hrs Type II 24-hr 50-yr Rainfall=5.23" Area (sf) CN Description 23,679 43 Woods/grass comb., Fair, HSG A 90,801 39 >75% Grass cover, Good, HSG A 114,480 40 Weighted Average 114,480 100.00% Pervious Area Tc Length Slope Velocity Capacity Description (min) (feet) (ft/ft) (ft/sec) (cfs) 35.1 250 0.0480 0.12 Sheet Flow, Woods Woods: Light underbrush n= 0.400 P2= 2.57" 2.2 150 0.0266 1.14 Shallow Concentrated Flow, Lawn Short Grass Pasture Kv= 7.0 fps 37.3 400 Total A-1 Treeworks - existing conditions Type // 24-hr 50-yr Rainfall=5.23" Prepared by Kevin L. Hastings, PE Printed 3/14/2017 HydroCADO 10.00-19 s/n 02365 ©2016 HydroCAD Software Solutions LLC Page 6 Summary for Subcatchment 3S: Subcatchment 3 Runoff = 0.31 cfs @ 13.42 hrs, Volume= 0.134 af, Depth= 0.42" Runoff by SCS TR-20 method, UH=SCS, Weighted-CN, Time Span= 0.00-72.00 hrs, dt= 0.05 hrs Type II 24-hr 50-yr Rainfall=5.23" Area (sf) CN Description 166,507 43 Woods/grass comb., Fair, HSG A 166,507 100.00% Pervious Area Tc Length Slope Velocity Capacity Description (min) (feet) (ft/ft) (ft/sec) (cfs) 84.0 240 0.0050 0.05 Sheet Flow, Woods Woods: Light underbrush n= 0.400 P2= 2.57" 6.0 190 0.0447 0.53 Shallow Concentrated Flow, Woods Forest w/Heavy Litter Kv= 2.5 fps 90.0 430 Total Summary for Reach DP-1: Design Point 1 Inflow Area = 3.086 ac, 43.89% Impervious, Inflow Depth = 1.81" for 50-yr event Inflow = 3.52 cfs @ 12.44 hrs, Volume= 0.465 of Outflow = 3.52 cfs @ 12.44 hrs, Volume= 0.465 af, Atten= 0%, Lag= 0.0 min Routing by Stor-Ind+Trans method, Time Span= 0.00-72.00 hrs, dt= 0.05 hrs Summary for Reach DP-2: Design Point 2 Inflow Area = 2.628 ac, 0.00% Impervious, Inflow Depth = 0.29" for 50-yr event Inflow = 0.16 cfs @ 12.66 hrs, Volume= 0.063 of Outflow = 0.16 cfs @ 12.66 hrs, Volume= 0.063 af, Atten= 0%, Lag= 0.0 min Routing by Stor-Ind+Trans method, Time Span= 0.00-72.00 hrs, dt= 0.05 hrs Summary for Reach DP-3: Design Point 3 Inflow Area = 3.822 ac, 0.00% Impervious, Inflow Depth = 0.42" for 50-yr event Inflow = 0.31 cfs @ 13.42 hrs, Volume= 0.134 of Outflow = 0.31 cfs @ 13.42 hrs, Volume= 0.134 af, Atten= 0%, Lag= 0.0 min Routing by Stor-Ind+Trans method, Time Span= 0.00-72.00 hrs, dt= 0.05 hrs A-1 Treeworks - existing conditions Type 11 24-hr 100-yr Rainfall=6.10" Prepared by Kevin L. Hastings, PE Printed 3/14/2017 HydroCAD® 10.00-19 s/n 02365 @2016 HydroCAD Software Solutions LLC Page 7 Summary for Subcatchment 1S: Subcatchment 1 Runoff = 4.85 cfs @ 12.43 hrs, Volume= 0.623 af, Depth= 2.42" Runoff by SCS TR-20 method, UH=SCS, Weighted-CN, Time Span= 0.00-72.00 hrs, dt= 0.05 hrs Type II 24-hr 100-yr Rainfall=6.10" Area (sf) CN Description 45,679 98 Paved parking, HSG A 7,521 43 Woods/grass comb., Fair, HSG A 13,317 98 Unconnected roofs, HSG A 67,909 39 >75% Grass cover, Good, HSG A 134,426 65 Weighted Average 75,430 56.11% Pervious Area 58,996 43.89% Impervious Area 13,317 22.57% Unconnected Tc Length Slope Velocity Capacity Description (min) (feet) (ft/ft) (ft/sec) (cfs) 41.3 300 0.0166 0.12 Sheet Flow, Lawn Grass: Dense n= 0.240 P2= 2.57" 2.0 175 0.0050 1.44 Shallow Concentrated Flow, Driveway Paved Kv= 20.3 fps 43.3 475 Total Summary for Subcatchment 2S: Subcatchment 2 Runoff = 0.46 cfs @ 12.51 hrs, Volume= 0.116 af, Depth= 0.53" Runoff by SCS TR-20 method, UH=SCS, Weighted-CN, Time Span= 0.00-72.00 hrs, dt= 0.05 hrs Type II 24-hr 100-yr Rainfall=6.10" Area (sf) CN Description 23,679 43 Woods/grass comb., Fair, HSG A 90,801 39 >75% Grass cover, Good, HSG A 114,480 40 Weighted Average 114,480 100.00% Pervious Area Tc Length Slope Velocity Capacity Description (min) (feet) (ft/ft) (ft/sec) (cfs) 35.1 250 0.0480 0.12 Sheet Flow, Woods Woods: Light underbrush n= 0.400 P2= 2.57" 2.2 150 0.0266 1.14 Shallow Concentrated Flow, Lawn Short Grass Pasture Kv= 7.0 fps 37.3 400 Total A-1 Treeworks - existing conditions Type 11 24-hr 100-yr Rainfall=6.10" Prepared by Kevin L. Hastings, PE Printed 3/14/2017 HydroCADO 10.00-19 s/n 02365 ©2016 HydroCAD Software Solutions LLC Page 8 Summary for Subcatchment 3S: Subcatchment 3 Runoff = 0.65 cfs @ 13.30 hrs, Volume= 0.227 af, Depth= 0.71" Runoff by SCS TR-20 method, UH=SCS, Weighted-CN, Time Span= 0.00-72.00 hrs, dt= 0.05 hrs Type II 24-hr 100-yr Rainfall=6.10" Area (sf) CN Description 166,507 43 Woods/grass comb., Fair, HSG A 166,507 100.00% Pervious Area Tc Length Slope Velocity Capacity Description (min) (feet) (ft/ft) (ft/sec) (cfs) 84.0 240 0.0050 0.05 Sheet Flow, Woods Woods: Light underbrush n= 0.400 P2= 2.57" 6.0 190 0.0447 0.53 Shallow Concentrated Flow, Woods Forest w/Heavy Litter Kv= 2.5 fps 90.0 430 Total Summary for Reach DP-1: Design Point 1 Inflow Area = 3.086 ac, 43.89% Impervious, Inflow Depth = 2.42" for 100-yr event Inflow = 4.85 cfs @ 12.43 hrs, Volume= 0.623 of Outflow = 4.85 cfs @ 12.43 hrs, Volume= 0.623 af, Atten= 0%, Lag= 0.0 min Routing by Stor-Ind+Trans method, Time Span= 0.00-72.00 hrs, dt= 0.05 hrs Summary for Reach DP-2: Design Point 2 Inflow Area = 2.628 ac, 0.00% Impervious, Inflow Depth = 0.53" for 100-yr event Inflow = 0.46 cfs @ 12.51 hrs, Volume= 0.116 of Outflow = 0.46 cfs @ 12.51 hrs, Volume= 0.116 af, Atten= 0%, Lag= 0.0 min Routing by Stor-Ind+Trans method, Time Span= 0.00-72.00 hrs, dt= 0.05 hrs Summary for Reach DP-3: Design Point 3 Inflow Area = 3.822 ac, 0.00% Impervious, Inflow Depth = 0.71" for 100-yr event Inflow = 0.65 cfs @ 13.30 hrs, Volume= 0.227 of Outflow = 0.65 cfs @ 13.30 hrs, Volume= 0.227 af, Atten= 0%, Lag= 0.0 min Routing by Stor-Ind+Trans method, Time Span= 0.00-72.00 hrs, dt= 0.05 hrs Appendix B Post-Development Conditions Subcatchment Map SC-2 HydroCad Drainage Diagram HydroCad Analysis Report dvm j "Gns C\2 .—Ppv 6..j..A "U"m't mnoa avou mjmmoj 0/S-80S DIVII s I-v —NINI—41" -1...16-3 6.,�I�...D Ig 'VIA3.V cL, <1 LJ CORINTHROAD U N J U) O c = moo o m O (-N- U Cyle) M v LO a) M � co a- d 70 2 M O O oap� o U) _ c o CD �aC) N LU Q (n O 2 d �o LO Q J NL UE �p .� o CN14 EY co L �, CV 70 o U) D � o N a c 0® 0 N � _ N m U N � � O � U) O � J N m r � � � o Q O U N r � ^I a U 7 Q C 0 A-1 Treeworks - proposed conditions Type // 24-hr 1-yr Rainfall=2.22" Prepared by Kevin L. Hastings, PE Printed 3/15/2017 HydroCAD® 10.00-19 s/n 02365 @2016 HydroCAD Software Solutions LLC Page 1 Summary for Subcatchment 1S: Subcatchment 1 Runoff = 0.39 cfs @ 12.54 hrs, Volume= 0.077 af, Depth= 0.30" Runoff by SCS TR-20 method, UH=SCS, Weighted-CN, Time Span= 0.00-72.00 hrs, dt= 0.05 hrs Type II 24-hr 1-yr Rainfall=2.22" Area (sf) CN Description 45,679 98 Paved parking, HSG A 7,521 43 Woods/grass comb., Fair, HSG A 13,317 98 Unconnected roofs, HSG A 57,945 39 >75% Grass cover, Good, HSG A 9,964 96 Gravel surface, HSG A 134,426 69 Weighted Average 75,430 56.11% Pervious Area 58,996 43.89% Impervious Area 13,317 22.57% Unconnected Tc Length Slope Velocity Capacity Description (min) (feet) (ft/ft) (ft/sec) (cfs) 41.3 300 0.0166 0.12 Sheet Flow, Lawn Grass: Dense n= 0.240 P2= 2.57" 2.0 175 0.0050 1.44 Shallow Concentrated Flow, Driveway Paved Kv= 20.3 fps 43.3 475 Total Summary for Subcatchment 2S: Subcatchment 2 Runoff = 0.02 cfs @ 13.79 hrs, Volume= 0.013 af, Depth= 0.06" Runoff by SCS TR-20 method, UH=SCS, Weighted-CN, Time Span= 0.00-72.00 hrs, dt= 0.05 hrs Type II 24-hr 1-yr Rainfall=2.22" Area (sf) CN Adj Description 7,289 43 Woods/grass comb., Fair, HSG A 66,326 39 >75% Grass cover, Good, HSG A 15,000 98 Unconnected roofs, HSG A 25,865 96 Gravel surface, HSG A 114,480 60 57 Weighted Average, UI Adjusted 99,480 86.90% Pervious Area 15,000 13.10% Impervious Area 15,000 100.00% Unconnected Tc Length Slope Velocity Capacity Description (min) (feet) (ft/ft) (ft/sec) (cfs) 35.1 250 0.0480 0.12 Sheet Flow, Woods Woods: Light underbrush n= 0.400 P2= 2.57" 2.2 150 0.0266 1.14 Shallow Concentrated Flow, Lawn Short Grass Pasture Kv= 7.0 fps 37.3 400 Total A-1 Treeworks - proposed conditions Type // 24-hr 1-yr Rainfall=2.22" Prepared by Kevin L. Hastings, PE Printed 3/15/2017 HydroCAD® 10.00-19 s/n 02365 @2016 HydroCAD Software Solutions LLC Page 2 Summary for Subcatchment 3S: Subcatchment 3 Runoff = 0.01 cfs @ 16.51 hrs, Volume= 0.012 af, Depth= 0.04" Runoff by SCS TR-20 method, UH=SCS, Weighted-CN, Time Span= 0.00-72.00 hrs, dt= 0.05 hrs Type II 24-hr 1-yr Rainfall=2.22" Area (sf) CN Description 42,658 43 Woods/grass comb., Fair, HSG A 80,472 39 >75% Grass cover, Good, HSG A 43,377 96 Gravel surface, HSG A 166,507 55 Weighted Average 166,507 100.00% Pervious Area Tc Length Slope Velocity Capacity Description (min) (feet) (ft/ft) (ft/sec) (cfs) 84.0 240 0.0050 0.05 Sheet Flow, Woods Woods: Light underbrush n= 0.400 P2= 2.57" 6.0 190 0.0447 0.53 Shallow Concentrated Flow, Woods Forest w/Heavy Litter Kv= 2.5 fps 90.0 430 Total Summary for Reach DP-1: Design Point 1 Inflow Area = 3.086 ac, 43.89% Impervious, Inflow Depth = 0.00" for 1-yr event Inflow = 0.00 cfs @ 0.00 hrs, Volume= 0.000 of Outflow = 0.00 cfs @ 0.00 hrs, Volume= 0.000 af, Atten= 0%, Lag= 0.0 min Routing by Stor-Ind+Trans method, Time Span= 0.00-72.00 hrs, dt= 0.05 hrs Summary for Reach DP-2: Design Point 2 Inflow Area = 2.628 ac, 13.10% Impervious, Inflow Depth = 0.00" for 1-yr event Inflow = 0.00 cfs @ 0.00 hrs, Volume= 0.000 of Outflow = 0.00 cfs @ 0.00 hrs, Volume= 0.000 af, Atten= 0%, Lag= 0.0 min Routing by Stor-Ind+Trans method, Time Span= 0.00-72.00 hrs, dt= 0.05 hrs Summary for Reach DP-3: Design Point 3 Inflow Area = 3.822 ac, 0.00% Impervious, Inflow Depth = 0.00" for 1-yr event Inflow = 0.00 cfs @ 0.00 hrs, Volume= 0.000 of Outflow = 0.00 cfs @ 0.00 hrs, Volume= 0.000 af, Atten= 0%, Lag= 0.0 min Routing by Stor-Ind+Trans method, Time Span= 0.00-72.00 hrs, dt= 0.05 hrs A-1 Treeworks - proposed conditions Type // 24-hr 1-yr Rainfall=2.22" Prepared by Kevin L. Hastings, PE Printed 3/15/2017 HydroCAD® 10.00-19 s/n 02365 @2016 HydroCAD Software Solutions LLC Page 3 Summary for Pond 1 P: Open Basin Inflow Area = 3.086 ac, 43.89% Impervious, Inflow Depth = 0.30" for 1-yr event Inflow = 0.39 cfs @ 12.54 hrs, Volume= 0.077 of Outflow = 0.21 cfs @ 13.12 hrs, Volume= 0.077 af, Atten= 47%, Lag= 35.0 min Discarded = 0.21 cfs @ 13.12 hrs, Volume= 0.077 of Primary = 0.00 cfs @ 0.00 hrs, Volume= 0.000 of Routing by Stor-Ind method, Time Span= 0.00-72.00 hrs, dt= 0.05 hrs Peak Elev= 499.59' @ 13.12 hrs Surf.Area= 1,191 sf Storage= 596 cf Plug-Flow detention time= 47.9 min calculated for 0.077 of(100% of inflow) Center-of-Mass det. time= 48.0 min ( 997.7 - 949.7 ) Volume Invert Avail.Storage Storage Description #1 499.00' 3,209 cf Surface Detention (Prismatic)Listed below 3,209 cf x 2.25 = 7,219 cf Total Available Storage Elevation Surf.Area Inc.Store Cum.Store (feet) (sq-ft) (cubic-feet) (cubic-feet) 499.00 0 0 0 500.00 900 450 450 501.00 1,296 1,098 1,548 502.00 2,025 1,661 3,209 Device Routing Invert Outlet Devices #1 Discarded 499.00' 7.500 in/hr Exfiltration over Surface area #2 Primary 501.75' 20.0' long x 5.0' 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) 2.34 2.50 2.70 2.68 2.68 2.66 2.65 2.65 2.65 2.65 2.67 2.66 2.68 2.70 2.74 2.79 2.88 Discarded OutFlow Max=0.21 cfs @ 13.12 hrs HW=499.59' (Free Discharge) L1=Exfiltration (Exfiltration Controls 0.21 cfs) Primary OutFlow Max=0.00 cfs @ 0.00 hrs HW=499.00' (Free Discharge) L2=Broad-crested Rectangular Weir( Controls 0.00 cfs) Summary for Pond 2P: Open Basin Inflow Area = 2.628 ac, 13.10% Impervious, Inflow Depth = 0.06" for 1-yr event Inflow = 0.02 cfs @ 13.79 hrs, Volume= 0.013 of Outflow = 0.02 cfs @ 14.33 hrs, Volume= 0.013 af, Atten= 5%, Lag= 32.5 min Discarded = 0.02 cfs @ 14.33 hrs, Volume= 0.013 of Primary = 0.00 cfs @ 0.00 hrs, Volume= 0.000 of Routing by Stor-Ind method, Time Span= 0.00-72.00 hrs, dt= 0.05 hrs Peak Elev= 500.51' @ 14.33 hrs Surf.Area= 102 sf Storage= 26 cf Plug-Flow detention time= 24.0 min calculated for 0.013 of(100% of inflow) A-1 Treeworks - proposed conditions Type // 24-hr 1-yr Rainfall=2.22" Prepared by Kevin L. Hastings, PE Printed 3/15/2017 HydroCAD® 10.00-19 s/n 02365 @2016 HydroCAD Software Solutions LLC Page 4 Center-of-Mass det. time= 24.0 min ( 1,104.8 - 1,080.8 ) Volume Invert Avail.Storage Storage Description #1 500.50' 25,850 cf Surface Detention (Prismatic)Listed below Elevation Surf.Area Inc.Store Cum.Store (feet) (sq-ft) (cubic-feet) (cubic-feet) 500.50 0 0 0 501.00 4,200 1,050 1,050 504.00 9,000 19,800 20,850 504.50 11,000 5,000 25,850 Device Routing Invert Outlet Devices #1 Discarded 500.50' 7.500 in/hr Exfiltration over Surface area #2 Primary 504.00' 20.0' long x 5.0' 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) 2.34 2.50 2.70 2.68 2.68 2.66 2.65 2.65 2.65 2.65 2.67 2.66 2.68 2.70 2.74 2.79 2.88 Discarded OutFlow Max=0.02 cfs @ 14.33 hrs HW=500.51' (Free Discharge) L1=Exfiltration (Exfiltration Controls 0.02 cfs) Primary OutFlow Max=0.00 cfs @ 0.00 hrs HW=500.50' (Free Discharge) L2=Broad-crested Rectangular Weir( Controls 0.00 cfs) Summary for Pond 3P: Open Basin Inflow Area = 3.822 ac, 0.00% Impervious, Inflow Depth = 0.04" for 1-yr event Inflow = 0.01 cfs @ 16.51 hrs, Volume= 0.012 of Outflow = 0.01 cfs @ 18.56 hrs, Volume= 0.012 af, Atten= 2%, Lag= 123.1 min Discarded = 0.01 cfs @ 18.56 hrs, Volume= 0.012 of Primary = 0.00 cfs @ 0.00 hrs, Volume= 0.000 of Routing by Stor-Ind method, Time Span= 0.00-72.00 hrs, dt= 0.05 hrs Peak Elev= 505.03' @ 18.56 hrs Surf.Area= 84 sf Storage= 42 cf Plug-Flow detention time= 47.9 min calculated for 0.012 of(100% of inflow) Center-of-Mass det. time= 48.0 min ( 1,223.0 - 1,175.0 ) Volume Invert Avail.Storage Storage Description #1 505.00' 15,250 cf Surface Detention (Prismatic)Listed below Elevation Surf.Area Inc.Store Cum.Store (feet) (sq-ft) (cubic-feet) (cubic-feet) 505.00 0 0 0 506.00 3,000 1,500 1,500 507.00 5,100 4,050 5,550 508.00 14,300 9,700 15,250 A-1 Treeworks - proposed conditions Type // 24-hr 1-yr Rainfall=2.22" Prepared by Kevin L. Hastings, PE Printed 3/15/2017 HydroCAD® 10.00-19 s/n 02365 @2016 HydroCAD Software Solutions LLC Page 5 Device Routing Invert Outlet Devices #1 Discarded 505.00' 7.500 in/hr Exfiltration over Surface area #2 Primary 507.95' 100.0' long x 5.0' 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) 2.34 2.50 2.70 2.68 2.68 2.66 2.65 2.65 2.65 2.65 2.67 2.66 2.68 2.70 2.74 2.79 2.88 Discarded OutFlow Max=0.01 cfs @ 18.56 hrs HW=505.03' (Free Discharge) L1=Exfiltration (Exfiltration Controls 0.01 cfs) Primary OutFlow Max=0.00 cfs @ 0.00 hrs HW=505.00' (Free Discharge) L2=Broad-crested Rectangular Weir( Controls 0.00 cfs) A-1 Treeworks - proposed conditions Type // 24-hr 10-yr Rainfall=3.66" Prepared by Kevin L. Hastings, PE Printed 3/15/2017 HydroCAD® 10.00-19 s/n 02365 @2016 HydroCAD Software Solutions LLC Page 6 Summary for Subcatchment 1S: Subcatchment 1 Runoff = 1.95 cfs @ 12.45 hrs, Volume= 0.270 af, Depth= 1.05" Runoff by SCS TR-20 method, UH=SCS, Weighted-CN, Time Span= 0.00-72.00 hrs, dt= 0.05 hrs Type II 24-hr 10-yr Rainfall=3.66" Area (sf) CN Description 45,679 98 Paved parking, HSG A 7,521 43 Woods/grass comb., Fair, HSG A 13,317 98 Unconnected roofs, HSG A 57,945 39 >75% Grass cover, Good, HSG A 9,964 96 Gravel surface, HSG A 134,426 69 Weighted Average 75,430 56.11% Pervious Area 58,996 43.89% Impervious Area 13,317 22.57% Unconnected Tc Length Slope Velocity Capacity Description (min) (feet) (ft/ft) (ft/sec) (cfs) 41.3 300 0.0166 0.12 Sheet Flow, Lawn Grass: Dense n= 0.240 P2= 2.57" 2.0 175 0.0050 1.44 Shallow Concentrated Flow, Driveway Paved Kv= 20.3 fps 43.3 475 Total Summary for Subcatchment 2S: Subcatchment 2 Runoff = 0.57 cfs @ 12.45 hrs, Volume= 0.105 af, Depth= 0.48" Runoff by SCS TR-20 method, UH=SCS, Weighted-CN, Time Span= 0.00-72.00 hrs, dt= 0.05 hrs Type II 24-hr 10-yr Rainfall=3.66" Area (sf) CN Adj Description 7,289 43 Woods/grass comb., Fair, HSG A 66,326 39 >75% Grass cover, Good, HSG A 15,000 98 Unconnected roofs, HSG A 25,865 96 Gravel surface, HSG A 114,480 60 57 Weighted Average, UI Adjusted 99,480 86.90% Pervious Area 15,000 13.10% Impervious Area 15,000 100.00% Unconnected Tc Length Slope Velocity Capacity Description (min) (feet) (ft/ft) (ft/sec) (cfs) 35.1 250 0.0480 0.12 Sheet Flow, Woods Woods: Light underbrush n= 0.400 P2= 2.57" 2.2 150 0.0266 1.14 Shallow Concentrated Flow, Lawn Short Grass Pasture Kv= 7.0 fps 37.3 400 Total A-1 Treeworks - proposed conditions Type // 24-hr 10-yr Rainfall=3.66" Prepared by Kevin L. Hastings, PE Printed 3/15/2017 HydroCAD® 10.00-19 s/n 02365 @2016 HydroCAD Software Solutions LLC Page 7 Summary for Subcatchment 3S: Subcatchment 3 Runoff = 0.35 cfs @ 13.31 hrs, Volume= 0.128 af, Depth= 0.40" Runoff by SCS TR-20 method, UH=SCS, Weighted-CN, Time Span= 0.00-72.00 hrs, dt= 0.05 hrs Type II 24-hr 10-yr Rainfall=3.66" Area (sf) CN Description 42,658 43 Woods/grass comb., Fair, HSG A 80,472 39 >75% Grass cover, Good, HSG A 43,377 96 Gravel surface, HSG A 166,507 55 Weighted Average 166,507 100.00% Pervious Area Tc Length Slope Velocity Capacity Description (min) (feet) (ft/ft) (ft/sec) (cfs) 84.0 240 0.0050 0.05 Sheet Flow, Woods Woods: Light underbrush n= 0.400 P2= 2.57" 6.0 190 0.0447 0.53 Shallow Concentrated Flow, Woods Forest w/Heavy Litter Kv= 2.5 fps 90.0 430 Total Summary for Reach DP-1: Design Point 1 Inflow Area = 3.086 ac, 43.89% Impervious, Inflow Depth = 0.00" for 10-yr event Inflow = 0.00 cfs @ 0.00 hrs, Volume= 0.000 of Outflow = 0.00 cfs @ 0.00 hrs, Volume= 0.000 af, Atten= 0%, Lag= 0.0 min Routing by Stor-Ind+Trans method, Time Span= 0.00-72.00 hrs, dt= 0.05 hrs Summary for Reach DP-2: Design Point 2 Inflow Area = 2.628 ac, 13.10% Impervious, Inflow Depth = 0.00" for 10-yr event Inflow = 0.00 cfs @ 0.00 hrs, Volume= 0.000 of Outflow = 0.00 cfs @ 0.00 hrs, Volume= 0.000 af, Atten= 0%, Lag= 0.0 min Routing by Stor-Ind+Trans method, Time Span= 0.00-72.00 hrs, dt= 0.05 hrs Summary for Reach DP-3: Design Point 3 Inflow Area = 3.822 ac, 0.00% Impervious, Inflow Depth = 0.00" for 10-yr event Inflow = 0.00 cfs @ 0.00 hrs, Volume= 0.000 of Outflow = 0.00 cfs @ 0.00 hrs, Volume= 0.000 af, Atten= 0%, Lag= 0.0 min Routing by Stor-Ind+Trans method, Time Span= 0.00-72.00 hrs, dt= 0.05 hrs A-1 Treeworks - proposed conditions Type // 24-hr 10-yr Rainfall=3.66" Prepared by Kevin L. Hastings, PE Printed 3/15/2017 HydroCAD® 10.00-19 s/n 02365 @2016 HydroCAD Software Solutions LLC Page 8 Summary for Pond 1 P: Open Basin Inflow Area = 3.086 ac, 43.89% Impervious, Inflow Depth = 1.05" for 10-yr event Inflow = 1.95 cfs @ 12.45 hrs, Volume= 0.270 of Outflow = 0.54 cfs @ 13.37 hrs, Volume= 0.270 af, Atten= 72%, Lag= 55.3 min Discarded = 0.54 cfs @ 13.37 hrs, Volume= 0.270 of Primary = 0.00 cfs @ 0.00 hrs, Volume= 0.000 of Routing by Stor-Ind method, Time Span= 0.00-72.00 hrs, dt= 0.05 hrs Peak Elev= 501.11' @ 13.37 hrs Surf.Area= 3,090 sf Storage= 3,880 cf Plug-Flow detention time= 81.0 min calculated for 0.270 of(100% of inflow) Center-of-Mass det. time= 81.1 min ( 981.8 - 900.8 ) Volume Invert Avail.Storage Storage Description #1 499.00' 3,209 cf Surface Detention (Prismatic)Listed below 3,209 cf x 2.25 = 7,219 cf Total Available Storage Elevation Surf.Area Inc.Store Cum.Store (feet) (sq-ft) (cubic-feet) (cubic-feet) 499.00 0 0 0 500.00 900 450 450 501.00 1,296 1,098 1,548 502.00 2,025 1,661 3,209 Device Routing Invert Outlet Devices #1 Discarded 499.00' 7.500 in/hr Exfiltration over Surface area #2 Primary 501.75' 20.0' long x 5.0' 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) 2.34 2.50 2.70 2.68 2.68 2.66 2.65 2.65 2.65 2.65 2.67 2.66 2.68 2.70 2.74 2.79 2.88 Discarded OutFlow Max=0.54 cfs @ 13.37 hrs HW=501.11' (Free Discharge) L1=Exfiltration (Exfiltration Controls 0.54 cfs) Primary OutFlow Max=0.00 cfs @ 0.00 hrs HW=499.00' (Free Discharge) L2=Broad-crested Rectangular Weir( Controls 0.00 cfs) Summary for Pond 2P: Open Basin Inflow Area = 2.628 ac, 13.10% Impervious, Inflow Depth = 0.48" for 10-yr event Inflow = 0.57 cfs @ 12.45 hrs, Volume= 0.105 of Outflow = 0.38 cfs @ 12.78 hrs, Volume= 0.105 af, Atten= 33%, Lag= 20.2 min Discarded = 0.38 cfs @ 12.78 hrs, Volume= 0.105 of Primary = 0.00 cfs @ 0.00 hrs, Volume= 0.000 of Routing by Stor-Ind method, Time Span= 0.00-72.00 hrs, dt= 0.05 hrs Peak Elev= 500.76' @ 12.78 hrs Surf.Area= 2,203 sf Storage= 551 cf Plug-Flow detention time= 24.0 min calculated for 0.104 of(100% of inflow) A-1 Treeworks - proposed conditions Type // 24-hr 10-yr Rainfall=3.66" Prepared by Kevin L. Hastings, PE Printed 3/15/2017 HydroCAD® 10.00-19 s/n 02365 @2016 HydroCAD Software Solutions LLC Page 9 Center-of-Mass det. time= 24.0 min ( 970.7 - 946.7 ) Volume Invert Avail.Storage Storage Description #1 500.50' 25,850 cf Surface Detention (Prismatic)Listed below Elevation Surf.Area Inc.Store Cum.Store (feet) (sq-ft) (cubic-feet) (cubic-feet) 500.50 0 0 0 501.00 4,200 1,050 1,050 504.00 9,000 19,800 20,850 504.50 11,000 5,000 25,850 Device Routing Invert Outlet Devices #1 Discarded 500.50' 7.500 in/hr Exfiltration over Surface area #2 Primary 504.00' 20.0' long x 5.0' 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) 2.34 2.50 2.70 2.68 2.68 2.66 2.65 2.65 2.65 2.65 2.67 2.66 2.68 2.70 2.74 2.79 2.88 Discarded OutFlow Max=0.38 cfs @ 12.78 hrs HW=500.76' (Free Discharge) L1=Exfiltration (Exfiltration Controls 0.38 cfs) Primary OutFlow Max=0.00 cfs @ 0.00 hrs HW=500.50' (Free Discharge) L2=Broad-crested Rectangular Weir( Controls 0.00 cfs) Summary for Pond 3P: Open Basin Inflow Area = 3.822 ac, 0.00% Impervious, Inflow Depth = 0.40" for 10-yr event Inflow = 0.35 cfs @ 13.31 hrs, Volume= 0.128 of Outflow = 0.26 cfs @ 14.07 hrs, Volume= 0.128 af, Atten= 26%, Lag= 45.6 min Discarded = 0.26 cfs @ 14.07 hrs, Volume= 0.128 of Primary = 0.00 cfs @ 0.00 hrs, Volume= 0.000 of Routing by Stor-Ind method, Time Span= 0.00-72.00 hrs, dt= 0.05 hrs Peak Elev= 505.50' @ 14.07 hrs Surf.Area= 1,502 sf Storage= 751 cf Plug-Flow detention time= 47.9 min calculated for 0.128 of(100% of inflow) Center-of-Mass det. time= 48.0 min ( 1,056.1 - 1,008.1 ) Volume Invert Avail.Storage Storage Description #1 505.00' 15,250 cf Surface Detention (Prismatic)Listed below Elevation Surf.Area Inc.Store Cum.Store (feet) (sq-ft) (cubic-feet) (cubic-feet) 505.00 0 0 0 506.00 3,000 1,500 1,500 507.00 5,100 4,050 5,550 508.00 14,300 9,700 15,250 A-1 Treeworks - proposed conditions Type // 24-hr 10-yr Rainfall=3.66" Prepared by Kevin L. Hastings, PE Printed 3/15/2017 HydroCADO 10.00-19 s/n 02365 ©2016 HydroCAD Software Solutions LLC Page 10 Device Routing Invert Outlet Devices #1 Discarded 505.00' 7.500 in/hr Exfiltration over Surface area #2 Primary 507.95' 100.0' long x 5.0' 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) 2.34 2.50 2.70 2.68 2.68 2.66 2.65 2.65 2.65 2.65 2.67 2.66 2.68 2.70 2.74 2.79 2.88 Discarded OutFlow Max=0.26 cfs @ 14.07 hrs HW=505.50' (Free Discharge) L1=Exfiltration (Exfiltration Controls 0.26 cfs) Primary OutFlow Max=0.00 cfs @ 0.00 hrs HW=505.00' (Free Discharge) L2=Broad-crested Rectangular Weir( Controls 0.00 cfs) A-1 Treeworks - proposed conditions Type 11 24-hr 50-yr Rainfall=5.23" Prepared by Kevin L. Hastings, PE Printed 3/15/2017 HydroCAD® 10.00-19 s/n 02365 @2016 HydroCAD Software Solutions LLC Page 11 Summary for Subcatchment 1S: Subcatchment 1 Runoff = 4.27 cfs @ 12.43 hrs, Volume= 0.547 af, Depth= 2.13" Runoff by SCS TR-20 method, UH=SCS, Weighted-CN, Time Span= 0.00-72.00 hrs, dt= 0.05 hrs Type II 24-hr 50-yr Rainfall=5.23" Area (sf) CN Description 45,679 98 Paved parking, HSG A 7,521 43 Woods/grass comb., Fair, HSG A 13,317 98 Unconnected roofs, HSG A 57,945 39 >75% Grass cover, Good, HSG A 9,964 96 Gravel surface, HSG A 134,426 69 Weighted Average 75,430 56.11% Pervious Area 58,996 43.89% Impervious Area 13,317 22.57% Unconnected Tc Length Slope Velocity Capacity Description (min) (feet) (ft/ft) (ft/sec) (cfs) 41.3 300 0.0166 0.12 Sheet Flow, Lawn Grass: Dense n= 0.240 P2= 2.57" 2.0 175 0.0050 1.44 Shallow Concentrated Flow, Driveway Paved Kv= 20.3 fps 43.3 475 Total Summary for Subcatchment 2S: Subcatchment 2 Runoff = 2.01 cfs @ 12.39 hrs, Volume= 0.269 af, Depth= 1.23" Runoff by SCS TR-20 method, UH=SCS, Weighted-CN, Time Span= 0.00-72.00 hrs, dt= 0.05 hrs Type II 24-hr 50-yr Rainfall=5.23" Area (sf) CN Adj Description 7,289 43 Woods/grass comb., Fair, HSG A 66,326 39 >75% Grass cover, Good, HSG A 15,000 98 Unconnected roofs, HSG A 25,865 96 Gravel surface, HSG A 114,480 60 57 Weighted Average, UI Adjusted 99,480 86.90% Pervious Area 15,000 13.10% Impervious Area 15,000 100.00% Unconnected Tc Length Slope Velocity Capacity Description (min) (feet) (ft/ft) (ft/sec) (cfs) 35.1 250 0.0480 0.12 Sheet Flow, Woods Woods: Light underbrush n= 0.400 P2= 2.57" 2.2 150 0.0266 1.14 Shallow Concentrated Flow, Lawn Short Grass Pasture Kv= 7.0 fps 37.3 400 Total A-1 Treeworks - proposed conditions Type // 24-hr 50-yr Rainfall=5.23" Prepared by Kevin L. Hastings, PE Printed 3/15/2017 HydroCADO 10.00-19 s/n 02365 ©2016 HydroCAD Software Solutions LLC Page 12 Summary for Subcatchment 3S: Subcatchment 3 Runoff = 1.31 cfs @ 13.13 hrs, Volume= 0.349 af, Depth= 1.10" Runoff by SCS TR-20 method, UH=SCS, Weighted-CN, Time Span= 0.00-72.00 hrs, dt= 0.05 hrs Type II 24-hr 50-yr Rainfall=5.23" Area (sf) CN Description 42,658 43 Woods/grass comb., Fair, HSG A 80,472 39 >75% Grass cover, Good, HSG A 43,377 96 Gravel surface, HSG A 166,507 55 Weighted Average 166,507 100.00% Pervious Area Tc Length Slope Velocity Capacity Description (min) (feet) (ft/ft) (ft/sec) (cfs) 84.0 240 0.0050 0.05 Sheet Flow, Woods Woods: Light underbrush n= 0.400 P2= 2.57" 6.0 190 0.0447 0.53 Shallow Concentrated Flow, Woods Forest w/Heavy Litter Kv= 2.5 fps 90.0 430 Total Summary for Reach DP-1: Design Point 1 Inflow Area = 3.086 ac, 43.89% Impervious, Inflow Depth = 0.35" for 50-yr event Inflow = 2.41 cfs @ 12.71 hrs, Volume= 0.089 of Outflow = 2.41 cfs @ 12.71 hrs, Volume= 0.089 af, Atten= 0%, Lag= 0.0 min Routing by Stor-Ind+Trans method, Time Span= 0.00-72.00 hrs, dt= 0.05 hrs Summary for Reach DP-2: Design Point 2 Inflow Area = 2.628 ac, 13.10% Impervious, Inflow Depth = 0.00" for 50-yr event Inflow = 0.00 cfs @ 0.00 hrs, Volume= 0.000 of Outflow = 0.00 cfs @ 0.00 hrs, Volume= 0.000 af, Atten= 0%, Lag= 0.0 min Routing by Stor-Ind+Trans method, Time Span= 0.00-72.00 hrs, dt= 0.05 hrs Summary for Reach DP-3: Design Point 3 Inflow Area = 3.822 ac, 0.00% Impervious, Inflow Depth = 0.00" for 50-yr event Inflow = 0.00 cfs @ 0.00 hrs, Volume= 0.000 of Outflow = 0.00 cfs @ 0.00 hrs, Volume= 0.000 af, Atten= 0%, Lag= 0.0 min Routing by Stor-Ind+Trans method, Time Span= 0.00-72.00 hrs, dt= 0.05 hrs A-1 Treeworks - proposed conditions Type 11 24-hr 50-yr Rainfall=5.23" Prepared by Kevin L. Hastings, PE Printed 3/15/2017 HydroCAD® 10.00-19 s/n 02365 @2016 HydroCAD Software Solutions LLC Page 13 Summary for Pond 1 P: Open Basin Inflow Area = 3.086 ac, 43.89% Impervious, Inflow Depth = 2.13" for 50-yr event Inflow = 4.27 cfs @ 12.43 hrs, Volume= 0.547 of Outflow = 3.17 cfs @ 12.71 hrs, Volume= 0.547 af, Atten= 26%, Lag= 16.7 min Discarded = 0.76 cfs @ 12.71 hrs, Volume= 0.458 of Primary = 2.41 cfs @ 12.71 hrs, Volume= 0.089 of Routing by Stor-Ind method, Time Span= 0.00-72.00 hrs, dt= 0.05 hrs Peak Elev= 501.89' @ 12.71 hrs Surf.Area= 4,373 sf Storage= 6,801 cf Plug-Flow detention time= 90.0 min calculated for 0.546 of(100% of inflow) Center-of-Mass det. time= 90.0 min ( 969.1 - 879.0 ) Volume Invert Avail.Storage Storage Description #1 499.00' 3,209 cf Surface Detention (Prismatic)Listed below 3,209 cf x 2.25 = 7,219 cf Total Available Storage Elevation Surf.Area Inc.Store Cum.Store (feet) (sq-ft) (cubic-feet) (cubic-feet) 499.00 0 0 0 500.00 900 450 450 501.00 1,296 1,098 1,548 502.00 2,025 1,661 3,209 Device Routing Invert Outlet Devices #1 Discarded 499.00' 7.500 in/hr Exfiltration over Surface area #2 Primary 501.75' 20.0' long x 5.0' 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) 2.34 2.50 2.70 2.68 2.68 2.66 2.65 2.65 2.65 2.65 2.67 2.66 2.68 2.70 2.74 2.79 2.88 Discarded OutFlow Max=0.76 cfs @ 12.71 hrs HW=501.89' (Free Discharge) L1=Exfiltration (Exfiltration Controls 0.76 cfs) Primary OutFlow Max=2.37 cfs @ 12.71 hrs HW=501.89' (Free Discharge) L2=Broad-crested Rectangular Weir(Weir Controls 2.37 cfs @ 0.87 fps) Summary for Pond 2P: Open Basin Inflow Area = 2.628 ac, 13.10% Impervious, Inflow Depth = 1.23" for 50-yr event Inflow = 2.01 cfs @ 12.39 hrs, Volume= 0.269 of Outflow = 0.79 cfs @ 12.97 hrs, Volume= 0.269 af, Atten= 61%, Lag= 34.8 min Discarded = 0.79 cfs @ 12.97 hrs, Volume= 0.269 of Primary = 0.00 cfs @ 0.00 hrs, Volume= 0.000 of Routing by Stor-Ind method, Time Span= 0.00-72.00 hrs, dt= 0.05 hrs Peak Elev= 501.24' @ 12.97 hrs Surf.Area= 4,578 sf Storage= 2,608 cf Plug-Flow detention time= 33.3 min calculated for 0.269 of(100% of inflow) A-1 Treeworks - proposed conditions Type // 24-hr 50-yr Rainfall=5.23" Prepared by Kevin L. Hastings, PE Printed 3/15/2017 HydroCADO 10.00-19 s/n 02365 ©2016 HydroCAD Software Solutions LLC Page 14 Center-of-Mass det. time= 33.2 min ( 940.8 - 907.6 ) Volume Invert Avail.Storage Storage Description #1 500.50' 25,850 cf Surface Detention (Prismatic)Listed below Elevation Surf.Area Inc.Store Cum.Store (feet) (sq-ft) (cubic-feet) (cubic-feet) 500.50 0 0 0 501.00 4,200 1,050 1,050 504.00 9,000 19,800 20,850 504.50 11,000 5,000 25,850 Device Routing Invert Outlet Devices #1 Discarded 500.50' 7.500 in/hr Exfiltration over Surface area #2 Primary 504.00' 20.0' long x 5.0' 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) 2.34 2.50 2.70 2.68 2.68 2.66 2.65 2.65 2.65 2.65 2.67 2.66 2.68 2.70 2.74 2.79 2.88 Discarded OutFlow Max=0.79 cfs @ 12.97 hrs HW=501.24' (Free Discharge) L1=Exfiltration (Exfiltration Controls 0.79 cfs) Primary OutFlow Max=0.00 cfs @ 0.00 hrs HW=500.50' (Free Discharge) L2=Broad-crested Rectangular Weir( Controls 0.00 cfs) Summary for Pond 3P: Open Basin Inflow Area = 3.822 ac, 0.00% Impervious, Inflow Depth = 1.10" for 50-yr event Inflow = 1.31 cfs @ 13.13 hrs, Volume= 0.349 of Outflow = 0.69 cfs @ 14.23 hrs, Volume= 0.349 af, Atten= 48%, Lag= 66.1 min Discarded = 0.69 cfs @ 14.23 hrs, Volume= 0.349 of Primary = 0.00 cfs @ 0.00 hrs, Volume= 0.000 of Routing by Stor-Ind method, Time Span= 0.00-72.00 hrs, dt= 0.05 hrs Peak Elev= 506.45' @ 14.23 hrs Surf.Area= 3,954 sf Storage= 3,341 cf Plug-Flow detention time= 60.0 min calculated for 0.349 of(100% of inflow) Center-of-Mass det. time= 60.0 min ( 1,023.7 - 963.6 ) Volume Invert Avail.Storage Storage Description #1 505.00' 15,250 cf Surface Detention (Prismatic)Listed below Elevation Surf.Area Inc.Store Cum.Store (feet) (sq-ft) (cubic-feet) (cubic-feet) 505.00 0 0 0 506.00 3,000 1,500 1,500 507.00 5,100 4,050 5,550 508.00 14,300 9,700 15,250 A-1 Treeworks - proposed conditions Type // 24-hr 50-yr Rainfall=5.23" Prepared by Kevin L. Hastings, PE Printed 3/15/2017 HydroCADO 10.00-19 s/n 02365 ©2016 HydroCAD Software Solutions LLC Page 15 Device Routing Invert Outlet Devices #1 Discarded 505.00' 7.500 in/hr Exfiltration over Surface area #2 Primary 507.95' 100.0' long x 5.0' 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) 2.34 2.50 2.70 2.68 2.68 2.66 2.65 2.65 2.65 2.65 2.67 2.66 2.68 2.70 2.74 2.79 2.88 Discarded OutFlow Max=0.69 cfs @ 14.23 hrs HW=506.45' (Free Discharge) L1=Exfiltration (Exfiltration Controls 0.69 cfs) Primary OutFlow Max=0.00 cfs @ 0.00 hrs HW=505.00' (Free Discharge) L2=Broad-crested Rectangular Weir( Controls 0.00 cfs) A-1 Treeworks - proposed conditions Type 11 24-hr 100-yr Rainfall=6.10" Prepared by Kevin L. Hastings, PE Printed 3/15/2017 HydroCAD® 10.00-19 s/n 02365 @2016 HydroCAD Software Solutions LLC Page 16 Summary for Subcatchment 1S: Subcatchment 1 Runoff = 5.70 cfs @ 12.42 hrs, Volume= 0.718 af, Depth= 2.79" Runoff by SCS TR-20 method, UH=SCS, Weighted-CN, Time Span= 0.00-72.00 hrs, dt= 0.05 hrs Type II 24-hr 100-yr Rainfall=6.10" Area (sf) CN Description 45,679 98 Paved parking, HSG A 7,521 43 Woods/grass comb., Fair, HSG A 13,317 98 Unconnected roofs, HSG A 57,945 39 >75% Grass cover, Good, HSG A 9,964 96 Gravel surface, HSG A 134,426 69 Weighted Average 75,430 56.11% Pervious Area 58,996 43.89% Impervious Area 13,317 22.57% Unconnected Tc Length Slope Velocity Capacity Description (min) (feet) (ft/ft) (ft/sec) (cfs) 41.3 300 0.0166 0.12 Sheet Flow, Lawn Grass: Dense n= 0.240 P2= 2.57" 2.0 175 0.0050 1.44 Shallow Concentrated Flow, Driveway Paved Kv= 20.3 fps 43.3 475 Total Summary for Subcatchment 2S: Subcatchment 2 Runoff = 3.04 cfs @ 12.37 hrs, Volume= 0.380 af, Depth= 1.74" Runoff by SCS TR-20 method, UH=SCS, Weighted-CN, Time Span= 0.00-72.00 hrs, dt= 0.05 hrs Type II 24-hr 100-yr Rainfall=6.10" Area (sf) CN Adj Description 7,289 43 Woods/grass comb., Fair, HSG A 66,326 39 >75% Grass cover, Good, HSG A 15,000 98 Unconnected roofs, HSG A 25,865 96 Gravel surface, HSG A 114,480 60 57 Weighted Average, UI Adjusted 99,480 86.90% Pervious Area 15,000 13.10% Impervious Area 15,000 100.00% Unconnected Tc Length Slope Velocity Capacity Description (min) (feet) (ft/ft) (ft/sec) (cfs) 35.1 250 0.0480 0.12 Sheet Flow, Woods Woods: Light underbrush n= 0.400 P2= 2.57" 2.2 150 0.0266 1.14 Shallow Concentrated Flow, Lawn Short Grass Pasture Kv= 7.0 fps 37.3 400 Total A-1 Treeworks - proposed conditions Type 11 24-hr 100-yr Rainfall=6.10" Prepared by Kevin L. Hastings, PE Printed 3/15/2017 HydroCADO 10.00-19 s/n 02365 ©2016 HydroCAD Software Solutions LLC Page 17 Summary for Subcatchment 3S: Subcatchment 3 Runoff = 2.04 cfs @ 13.11 hrs, Volume= 0.502 af, Depth= 1.58" Runoff by SCS TR-20 method, UH=SCS, Weighted-CN, Time Span= 0.00-72.00 hrs, dt= 0.05 hrs Type II 24-hr 100-yr Rainfall=6.10" Area (sf) CN Description 42,658 43 Woods/grass comb., Fair, HSG A 80,472 39 >75% Grass cover, Good, HSG A 43,377 96 Gravel surface, HSG A 166,507 55 Weighted Average 166,507 100.00% Pervious Area Tc Length Slope Velocity Capacity Description (min) (feet) (ft/ft) (ft/sec) (cfs) 84.0 240 0.0050 0.05 Sheet Flow, Woods Woods: Light underbrush n= 0.400 P2= 2.57" 6.0 190 0.0447 0.53 Shallow Concentrated Flow, Woods Forest w/Heavy Litter Kv= 2.5 fps 90.0 430 Total Summary for Reach DP-1: Design Point 1 Inflow Area = 3.086 ac, 43.89% Impervious, Inflow Depth = 0.77" for 100-yr event Inflow = 4.55 cfs @ 12.56 hrs, Volume= 0.197 of Outflow = 4.55 cfs @ 12.56 hrs, Volume= 0.197 af, Atten= 0%, Lag= 0.0 min Routing by Stor-Ind+Trans method, Time Span= 0.00-72.00 hrs, dt= 0.05 hrs Summary for Reach DP-2: Design Point 2 Inflow Area = 2.628 ac, 13.10% Impervious, Inflow Depth = 0.00" for 100-yr event Inflow = 0.00 cfs @ 0.00 hrs, Volume= 0.000 of Outflow = 0.00 cfs @ 0.00 hrs, Volume= 0.000 af, Atten= 0%, Lag= 0.0 min Routing by Stor-Ind+Trans method, Time Span= 0.00-72.00 hrs, dt= 0.05 hrs Summary for Reach DP-3: Design Point 3 Inflow Area = 3.822 ac, 0.00% Impervious, Inflow Depth = 0.00" for 100-yr event Inflow = 0.00 cfs @ 0.00 hrs, Volume= 0.000 of Outflow = 0.00 cfs @ 0.00 hrs, Volume= 0.000 af, Atten= 0%, Lag= 0.0 min Routing by Stor-Ind+Trans method, Time Span= 0.00-72.00 hrs, dt= 0.05 hrs A-1 Treeworks - proposed conditions Type 11 24-hr 100-yr Rainfall=6.10" Prepared by Kevin L. Hastings, PE Printed 3/15/2017 HydroCAD® 10.00-19 s/n 02365 @2016 HydroCAD Software Solutions LLC Page 18 Summary for Pond 1 P: Open Basin Inflow Area = 3.086 ac, 43.89% Impervious, Inflow Depth = 2.79" for 100-yr event Inflow = 5.70 cfs @ 12.42 hrs, Volume= 0.718 of Outflow = 5.33 cfs @ 12.56 hrs, Volume= 0.718 af, Atten= 7%, Lag= 8.3 min Discarded = 0.78 cfs @ 12.56 hrs, Volume= 0.521 of Primary = 4.55 cfs @ 12.56 hrs, Volume= 0.197 of Routing by Stor-Ind method, Time Span= 0.00-72.00 hrs, dt= 0.05 hrs Peak Elev= 501.96' @ 12.56 hrs Surf.Area= 4,491 sf Storage= 7,071 cf Plug-Flow detention time= 80.3 min calculated for 0.717 of(100% of inflow) Center-of-Mass det. time= 80.4 min ( 951.5 - 871.1 ) Volume Invert Avail.Storage Storage Description #1 499.00' 3,209 cf Surface Detention (Prismatic)Listed below 3,209 cf x 2.25 = 7,219 cf Total Available Storage Elevation Surf.Area Inc.Store Cum.Store (feet) (sq-ft) (cubic-feet) (cubic-feet) 499.00 0 0 0 500.00 900 450 450 501.00 1,296 1,098 1,548 502.00 2,025 1,661 3,209 Device Routing Invert Outlet Devices #1 Discarded 499.00' 7.500 in/hr Exfiltration over Surface area #2 Primary 501.75' 20.0' long x 5.0' 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) 2.34 2.50 2.70 2.68 2.68 2.66 2.65 2.65 2.65 2.65 2.67 2.66 2.68 2.70 2.74 2.79 2.88 Discarded OutFlow Max=0.78 cfs @ 12.56 hrs HW=501.96' (Free Discharge) L1=Exfiltration (Exfiltration Controls 0.78 cfs) Primary OutFlow Max=4.47 cfs @ 12.56 hrs HW=501.96' (Free Discharge) L2=Broad-crested Rectangular Weir(Weir Controls 4.47 cfs @ 1.07 fps) Summary for Pond 2P: Open Basin Inflow Area = 2.628 ac, 13.10% Impervious, Inflow Depth = 1.74" for 100-yr event Inflow = 3.04 cfs @ 12.37 hrs, Volume= 0.380 of Outflow = 0.89 cfs @ 13.12 hrs, Volume= 0.380 af, Atten= 71%, Lag= 44.8 min Discarded = 0.89 cfs @ 13.12 hrs, Volume= 0.380 of Primary = 0.00 cfs @ 0.00 hrs, Volume= 0.000 of Routing by Stor-Ind method, Time Span= 0.00-72.00 hrs, dt= 0.05 hrs Peak Elev= 501.57' @ 13.12 hrs Surf.Area= 5,115 sf Storage= 4,825 cf Plug-Flow detention time= 50.7 min calculated for 0.380 of(100% of inflow) A-1 Treeworks - proposed conditions Type 11 24-hr 100-yr Rainfall=6.10" Prepared by Kevin L. Hastings, PE Printed 3/15/2017 HydroCADO 10.00-19 s/n 02365 ©2016 HydroCAD Software Solutions LLC Page 19 Center-of-Mass det. time= 50.7 min ( 946.4 - 895.7 ) Volume Invert Avail.Storage Storage Description #1 500.50' 25,850 cf Surface Detention (Prismatic)Listed below Elevation Surf.Area Inc.Store Cum.Store (feet) (sq-ft) (cubic-feet) (cubic-feet) 500.50 0 0 0 501.00 4,200 1,050 1,050 504.00 9,000 19,800 20,850 504.50 11,000 5,000 25,850 Device Routing Invert Outlet Devices #1 Discarded 500.50' 7.500 in/hr Exfiltration over Surface area #2 Primary 504.00' 20.0' long x 5.0' 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) 2.34 2.50 2.70 2.68 2.68 2.66 2.65 2.65 2.65 2.65 2.67 2.66 2.68 2.70 2.74 2.79 2.88 Discarded OutFlow Max=0.89 cfs @ 13.12 hrs HW=501.57' (Free Discharge) L1=Exfiltration (Exfiltration Controls 0.89 cfs) Primary OutFlow Max=0.00 cfs @ 0.00 hrs HW=500.50' (Free Discharge) L2=Broad-crested Rectangular Weir( Controls 0.00 cfs) Summary for Pond 3P: Open Basin Inflow Area = 3.822 ac, 0.00% Impervious, Inflow Depth = 1.58" for 100-yr event Inflow = 2.04 cfs @ 13.11 hrs, Volume= 0.502 of Outflow = 0.94 cfs @ 14.29 hrs, Volume= 0.502 af, Atten= 54%, Lag= 71.1 min Discarded = 0.94 cfs @ 14.29 hrs, Volume= 0.502 of Primary = 0.00 cfs @ 0.00 hrs, Volume= 0.000 of Routing by Stor-Ind method, Time Span= 0.00-72.00 hrs, dt= 0.05 hrs Peak Elev= 507.03' @ 14.29 hrs Surf.Area= 5,412 sf Storage= 5,879 cf Plug-Flow detention time= 76.9 min calculated for 0.502 of(100% of inflow) Center-of-Mass det. time= 76.6 min ( 1,027.1 - 950.6 ) Volume Invert Avail.Storage Storage Description #1 505.00' 15,250 cf Surface Detention (Prismatic)Listed below Elevation Surf.Area Inc.Store Cum.Store (feet) (sq-ft) (cubic-feet) (cubic-feet) 505.00 0 0 0 506.00 3,000 1,500 1,500 507.00 5,100 4,050 5,550 508.00 14,300 9,700 15,250 A-1 Treeworks - proposed conditions Type 11 24-hr 100-yr Rainfall=6.10" Prepared by Kevin L. Hastings, PE Printed 3/15/2017 HydroCADO 10.00-19 s/n 02365 ©2016 HydroCAD Software Solutions LLC Page 20 Device Routing Invert Outlet Devices #1 Discarded 505.00' 7.500 in/hr Exfiltration over Surface area #2 Primary 507.95' 100.0' long x 5.0' 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) 2.34 2.50 2.70 2.68 2.68 2.66 2.65 2.65 2.65 2.65 2.67 2.66 2.68 2.70 2.74 2.79 2.88 Discarded OutFlow Max=0.94 cfs @ 14.29 hrs HW=507.03' (Free Discharge) L1=Exfiltration (Exfiltration Controls 0.94 cfs) Primary OutFlow Max=0.00 cfs @ 0.00 hrs HW=505.00' (Free Discharge) L2=Broad-crested Rectangular Weir( Controls 0.00 cfs) Appendix C Soils Mapping "A" NRCS Soil Resource Reports Soil Map—Warren County, New York (A-1 Treeworks) 605700 6W800 6W900 606000 606100 606200 606300 606400 43°18'9"N _� � T - I � � � � � L� 43°18'9"N OW 4. _•inn` '� Y ' � .. �... .. •� p•� ��� r �y .ic 747j j�•� b fes. �� -'� ' ^'. ':�" �• .ate S ,Q VI r �F• Y 't #; ;'1{ i1 ' " r y' .Y• w «fir- - ,•i.�,""' a fit, Soil MaN may not he valiel at this scale. �" �" '�,�'� "�" 430 1735"N `YI� I 430 1735"N 605700 6D5800 6W900 606000 606100 606200 606300 606400 3: 3: b En Map Scale:1:5,090 if printed on A portrait(8.5"x 11")sheet. ` Meters ` N 0 50 100 200 500 Feet 0 200 400 800 1200 Map projection:Web Mercator Conermordinates:WGS84 Edge tics:lfrM Zone 18N WGS84 USDA Natural Resources Web Soil Survey 3/14/2017 Conservation Service National Cooperative Soil Survey Pagel of 3 � 2 0 0 N N y � U _ m 0 a) a) N m N a) I O O Q U O V p m y 3 C � U y 2 m L � y � E °� 0 o a) 2 E a) p m 0 a) a) -O U) 6 N — Q 7 N E (n > -.— N O- — U E CL U N O C > N � U m O m Z E o m — m g u) a) a U voi O o m m a) m ao Q U o a) m a) Y aaci a) U) E m (n3 y a) C7 O N Z 0 0 n E y o a 3 y rn a) o Q U) U -0a) o m N o > O c m Cc: a a) y m Q a) a) O °) Q y E U w m m 0 2 U) a) N m m a) Q m cmi m ami s y p N Z Q a) o m Q -0 o m w E y - m 2 o = i� m o Q vi m O >. > 0 O a) O O U >, .2 a) O 7 (O N O � >, N N LL a) a) — c m o y a) a) o o ' E a) O U) i5 � a) Z w .m O a) o °) O U m Q v°)i E a) a) � u) o n c o m m `m CL 0 Q U mU 3 J > O N Q'C O N — N O -O O m E QOm � m � � � Q � C a) n m a) oNO -0 yE y > °? s 0)m is a) E `o rn a) rn o- a) >, a) m m N p y — O m Q 'o m ate) y O ami 3 U m .o Q m 'E m s c E U a) N Ern E U °? E m o `o a) Q m y E 0 — o — m a m =0 -0 o o °) N a) a) o coi a) °? o > 3 > m o a) rn U) 2) m U) U) U � y N m Q a, U a) E o y o o ' a) a) N E m vii aa) t m m m -a O Q.a? a) c3i w = L = p N a) E '!5 s .S� o (-) °) a) o a) o m o y U s 0 = o LP m s 0 s H � S w E — U y a E u) C) 2 Q o Q m H o U) U) U) � � H U . y Y } a) a) 3 Z � C 1 U) 3O 3 a) U U) — a) = m C N o N N U) Q 42 y -0 O Q N a) O T U L Q o aa)i (� L m m C- LL a a O T a) 2 y a -yo O '0 a) Q 0 0 J N O O L Z U Q °- m E m o a 0 ° R m CL O N L y a U � R C 0 R 0 p a) Z LL O O LU F m LU J y CL 0 y o a ) 1 o O o N Q a Q a U C C C a) Q a > > > R Ro o OQ Q CL o o = yOomw w )O o UUa) ov aO Q o y 3 LL R LL o Q a) a y o 0 0 o o R o R y o o m R o a o Q U) U) U) —p m m U U (7 (7 J J a U) U) U) in U) U) w a � R HEl I 20! o 0 a y o U) ,O L L 7N w 0 r0 O Z��U �!`51 Soil Map—Warren County, New York A-1 Treeworks Map Unit Legend Warren County,New York(NY113) Map Unit Symbol Map Unit Name Acres in AOI Percent of AOI OaA Oakville loamy fine sand,0 to 79.6 80.5% 3 percent slopes OaB Oakville loamy fine sand,3 to 19.3 19.5% 8 percent slopes Totals for Area of Interest 98.9 100.0% USDA Natural Resources Web Soil Survey 3/14/2017 Conservation Service National Cooperative Soil Survey Page 3 of 3 Map Unit Description: Oakville loamy fine sand,3 to 8 percent slopes---Warren County, New A-1 Treeworks York Warren County, New York OaB—Oakville loamy fine sand, 3 to 8 percent slopes Map Unit Setting National map unit symbol: 9xxd Elevation: 600 to 1,200 feet Mean annual precipitation: 37 to 46 inches Mean annual air temperature: 45 to 48 degrees F Frost-free period: 110 to 160 days Farmland classification: All areas are prime farmland Map Unit Composition Oakville and similar soils: 90 percent Minor components: 10 percent Estimates are based on observations, descriptions, and transects of the mapunit. Description of Oakville Setting Landform: Deltas, outwash plains, terraces Landform position (two-dimensional): Summit Landform position (three-dimensional): Tread Down-slope shape: Convex Across-slope shape: Convex Parent material: Sandy eolian, beach ridge, or glaciofluvial deposits Typical profile H1 -0 to 8 inches: loamy fine sand H2-8 to 27 inches: sand H3-27 to 60 inches: sand Properties and qualities Slope: 3 to 8 percent Depth to restrictive feature: More than 80 inches Natural drainage class: Well drained Capacity of the most limiting layer to transmit water(Ksat): High to very high (5.95 to 19.98 in/hr) Depth to water table: More than 80 inches Frequency of flooding: None Frequency of ponding: None Available water storage in profile: Low (about 4.4 inches) Interpretive groups Land capability classification (irrigated): None specified Land capability classification (nonirrigated): 2s Hydrologic Soil Group: A Hydric soil rating: No USDA Natural Resources Web Soil Survey 3/14/2017 Conservation Service National Cooperative Soil Survey Pagel of 2 Map Unit Description: Oakville loamy fine sand,3 to 8 percent slopes---Warren County, New A-1 Treeworks York Minor Components Tioga Percent of map unit: 4 percent Hydric soil rating: No Elnora Percent of map unit: 3 percent Hydric soil rating: No Hinckley Percent of map unit: 3 percent Hydric soil rating: No Data Source Information Soil Survey Area: Warren County, New York Survey Area Data: Version 16, Sep 24, 2016 USDA Natural Resources Web Soil Survey 3/14/2017 Conservation Service National Cooperative Soil Survey Page 2 of 2 Appendix D Water Quality Volume Calculations Appendix E Stormwater Maintenance Agreement