UPDATED SITE DESIGN NARRATIVE AND CALCULATIONS

Transcription

1 UPDATED SITE DESIGN NARRATIVE AND CALCULATIONS Burlington Summit The Gutierrez Company One Wall Street, Burlington, MA July, Prepared by, Symmes Maini & McKee Associates Cambridge, MA SMMA No.

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3 PROJECT DESCRIPTION OVERVIEW The project site is the combination of a series of parcels of land located at the end of Wheeler Road (West) in Burlington. The parcels comprise the existing Wheeler Road Development, the adjacent undeveloped land including the Land Swap parcel, and a acre parcel owned by the Massachusetts Highway Department (MassDOT) but under the control of The Gutierrez Company. The overall site measures. acres. Wheeler Road (Lot A). Acres & Wheeler Road (Lot A). Acres MassDOT Parcel. Acres The site is bounded to the north by Wheeler Road, to the east by commercial land properties and Middlesex Turnpike, to the south by commercial land properties, the Burlington Housing Authority land and to the west by land within the Town of Lexington. The project site has been the subject of previous permitting by The Gutierrez including the most recent Site Plan Amendment approved in as well as an Erosion & Sediment Control Permit approved in. The approved project included the development of the & Wheeler Road site with two buildings with a total of, sf of Gross Floor Area and a total parking count for the overall site (including Wheeler Road) of, parking spaces. PROPOSED AMENDMENT Following completion of the permitting efforts, The Gutierrez Company identified an opportunity for development of the site as a singular building constructed in phases, therefore the Gutierrez Company seeks to amend the site plan that was previously approved by the Planning Board and the Erosion & Sediment Control Approval from the Conservation Commission. The proposed amendment primarily consists of: Combine the two separate buildings ( & Wheeler Road) into a singular phased building Adjust the vehicular circulation and parking configuration to respond to a singular building Adjust the stormwater management and site utilities to support the revised parking and circulation Symmes Maini & McKee Associates July

4 Maintain the overall limit of disturbance of the project Maintain the overall stormwater design intent including quantities and size of Best Management Practices STORMWATER MANAGEMENT The proposed project was originally designed and approved in and was subject to the previous version of the Massachusetts Stormwater Management Policy. Subsequent to the original approval, MA DEP enacted the Stormwater Management Policy. The proposed project has been designed so that the additional impervious surface proposed to support the additional, sf Building area has been designed to comply with the Stormwater Management Policy. The stormwater management approach remains consistent with previously approved permits with minor modifications to support the revised layout. CONSISTENCY WITH DEP STORMWATER MANAGEMENT POLICY The project s compliance with each of the standards of the DEP Stormwater Policy is discussed below. Standard Untreated Stormwater Standard states that No new stormwater conveyances (e.g. outfalls) will discharge untreated stormwater directly to or cause erosion in wetlands or waters of the Commonwealth. The project provides treatment of all impervious areas of the site, and therefore there will be no untreated stormwater conveyances from the proposed project. Standard Post Development Peak Discharge Rates Standard states that Stormwater management systems shall be designed so that post-development peak discharge rates do not exceed pre-development peak discharge rates. The proposed project is designed so that post-development peak discharge rates do not exceed pre-development peak discharge rates. The existing and proposed conditions hydrology was modeled using Hydrocad to compare existing and proposed conditions. A detailed description of the project hydrology is included in the following section, Hydrologic Analysis. As described in detail in the Hydrologic Analysis Section, the project is in compliance with Standard. Symmes Maini & McKee Associates July

5 Standard Recharge to Groundwater Standard states that Loss of annual recharge to groundwater shall be eliminated or minimized through the use of infiltration measures including environmentally sensitive site design, low impact development techniques, stormwater best management practices, and good operation and maintenance. At a minimum, the annual recharge from the post-development site shall approximate the annual recharge from pre-development conditions based on soil type. This condition is met when the stormwater management system is designed to infiltrate the required recharge volume as determined in accordance with the Massachusetts Stormwater Handbook. The Burlington Summit project was originally designed and permitted in and provided rooftop recharge to groundwater. The project was recently approved to increase the building area to, sf and increase the quantity of parking to support the increased building area. In order to mitigate the impact of the increased impervious surface associated with this increased development, the project provides an additional subsurface recharge area. The recharge area was designed to exceed the minimum recharge volume to mitigate the increased impervious area. Detailed calculations are provided in Appendix Two. Standard Removal of % Total Suspended Solids (TSS) Standard states that Stormwater management systems shall be designed to remove % of the average annual post-construction load of Total Suspended Solids (TSS). This Standard is met when: (a) Suitable practices for source control and pollution prevention are identified in long-term pollution prevention plan, and thereafter implemented and maintained; (b) Structural stormwater best management practices are sized to capture the required water quality volume determined in accordance with the Massachusetts Stormwater Handbook; and (c) Pretreatment is provided in accordance with the Massachusetts Stormwater Handbook. Removal of Total Suspended Solids (TSS) is proposed for the site. TSS removal is accomplished by the combination of the following structural BMPs: Deep sump Catch Basins with hoods Water Quality Treatment Units (sized to provide TSS removal based on the proposed location) Subsurface Infiltration Basin Extended Dry Detention Basins Symmes Maini & McKee Associates July

6 In order to confirm that the project provides the minimum pretreatment required, the TSS removal efficiencies were calculated for the pretreatment and full treatment trains. The pretreatment required for the project is % due to its characterization as a Land Use of Higher Potential Pollutant. The project meets the requirement for % minimum TSS removal. Standard Land Uses with Higher Potential Pollutant Loads Standard states that For land uses with higher potential pollutant loads, source control and pollution prevention shall be implemented in accordance with the Massachusetts Stormwater Handbook to eliminate or reduce the discharge of stormwater runoff from such land uses to the maximum extent practicable. If through source control and/or pollution prevention all land uses with higher potential pollutant loads cannot be completely protected from exposure to rain, snow, snow melt, and stormwater runoff, the proponent shall use the specific structural stormwater BMPs determined by the Department to be suitable for such uses as provided in the Massachusetts Stormwater Handbook. In addition, land uses with higher potential pollutant loads include: exterior fleet storage areas; exterior vehicle service maintenance and cleaning areas; marinas and boatyards; and parking lots with highintensity-uses ( vehicle trips per day or more). The project site is characterized as a Land Use of Higher Potential Pollutant Load (LUHPPL) due to the fact that the site will have more than, average daily trips (ADT). The design of the stormwater management system complies with the requirements for LUHPPLs. Standard Critical Areas Standard states that Stormwater discharges within the Zone II or Interim Wellhead Protection Area of a public water supply and stormwater discharges near or to any other critical area require the use of the specific source control and pollution prevention measures and the specific structural stormwater best management practices determined by the Department to be suitable for managing discharges to such areas as provided in the Massachusetts Stormwater Handbook. The site is not located within a critical area; therefore this standard does not apply. Standard - Redevelopment Standard states that A redevelopment project is required to meet the following Stormwater Management Standards only to the maximum extent practicable: Standard, Standard, and the pretreatment and structural best management practice requirements of Symmes Maini & McKee Associates July

7 Standards, and. Existing stormwater discharges shall comply with Standard only to the maximum extent practicable. A redevelopment project shall also comply with all other requirements of the Stormwater Management Standards and improve existing conditions. The site is not characterized as a Redevelopment. Standard Erosion and Sedimentation Controls Standard states that A plan to control construction related impacts including erosion, sedimentation and other pollutant sources during construction and land disturbance activities (construction period erosion, sedimentation, and pollution prevention plan) shall be developed and implemented. The project is required to comply with the National Pollutant Discharge Elimination System (NPDES). The plans indicate locations of erosion and sediment controls including haybales with silt fence and temporary swales and sedimentation basins. The Project complies with Standard. Standard Operation and Maintenance Plans Standard states: A long-term operation and maintenance plan shall be developed and implemented to ensure that stormwater management systems function as designed. A long-term operation and maintenance plan is included in Appendix Four. Therefore the Project complies with Standard. Standard Illicit Discharges to Drainage System Standard states: All illicit discharges to the stormwater management system are prohibited. There are no known or suspected illicit discharges to the stormwater management system at the project site. The project complies with Standard. HYDROLOGIC ANALYSIS EXISTING HYDROLOGY The hydrologic analysis for the proposed site plan amendment represents an update to the hydrologic analysis for the previously approved site plan. The primary update to the existing conditions hydrology is to add new Symmes Maini & McKee Associates July

8 subcatchments representing the additional land area which is being added to the overall project site. The existing conditions hydrology for the overall site is split into two primary design points. Design Point represents the overland flow which flows across the southern property boundary of the site. This Design Point includes the flow from Subcatchments S and SB. Design Point represents the flow which discharges to the North across Route. This design point includes the flow from the remaining subcatchments and detention basins. The existing site hydrology was modeled with a TR- analysis using the HydroCAD version. software package (see Appendix, for the Hydologic Analysis). The existing site hydrology for the analyzed area is divided into three drainage discharge points as documented in Appendix. PROPOSED HYDROLOGY The proposed stormwater management system has been designed to mitigate the impacts of the proposed development. The hydrologic calculations compare the peak rates of runoff from the existing and proposed development at the two same Design Points. Detailed breakdown of the proposed hydrology subcatchments are shown on the hydrology figures attached to this report. Within the developed land there are components which mitigate peak rates of runoff, and provide for TSS removal. The proposed subcatchments are largely paved roadways, parking, sidewalk and landscaped areas as well as the proposed detention basin area. These areas all drain by deep sump, hooded, catch basins. Underground detention basins and the surface basin are routed and discharged to the Route Commonwealth of Massachusetts/MassDOT Parcel. These subsystems provide the majority of TSS removal and contribute to peak flow mitigation. The existing and proposed runoffs are summarized in Table below. In summary, the proposed site stormwater drainage system will decrease peak flows to the Route Commonwealth of Massachusetts/MassDOT parcel, the land to the south and east, and the total discharge overall for the, & -year storms, as shown in Table, and the Hydrologic Analysis in Appendix. Additional benefits will also be provided by the use of hooded deep sump catch basins, the detention/recharge ponds, the roof recharge areas, and a site maintenance program. These benefits result in a TSS removal of over %. Symmes Maini & McKee Associates July

9 Table : Hydrology Comparison Year Year Year Existing Proposed Existing Proposed Existing Proposed Design Point Design Point. cfs. cfs. cfs. cfs. cfs. cfs. cfs. cfs. cfs. cfs. cfs. cfs EROSION AND SEDIMENT CONTROL An erosion and sedimentation control plan was reviewed and approved by the Town of Burlington Conservation Commission. The plan complies with the Town of Burlington Bylaw, the Massachusetts Department of Environmental Protection s Stormwater Management Policy and the Environmental Protection Agency (EPA) National Pollutant Discharge Elimination System (NPDES) requirements. The Erosion and Sedimentation Control Plan was developed based on the anticipated construction of the proposed project. In the event that the proposed construction sequence changes, the erosion and sedimentation control plan will be adjusted to ensure proper measures are in place to protect downstream locations. ANTICIPATED CONSTRUCTION SEQUENCE The proposed project is expected to proceed in the following sequence of activites: o o o o o o Installation of Haybales with Silt Fence Clear and Grub Trees Remove Topsoil and Subsoil Install Temporary Sedimentation Basins Earthwork operations; Construct Proposed Buildings Symmes Maini & McKee Associates July

10 o o Install Utilities Install Pavement, Landscaping, and final Site Improvements PROPOSED EROSION AND SEDIMENTATION CONTROLS The following erosion and sedimentation control measures will be implements on the project site: o o o o o Installation of Haybales with Silt Fence at the perimeter of construction activities as shown on the design plans; Installation of sediment bags at existing catch basins; Installation of a temporary construction entrance where vehicles will enter and exit the project site; Installation of temporary sedimentation basins and drainage swales to collect and treat runoff from exposed surfaces; and Installation of temporary stabilization methods for soil stockpiles. TEMPORARY SEDIMENTATION BASINS The temporary sedimentation basins have been sized to pass the -year hour storm event in accordance with the applicable requirements. The discharge from the temporary sedimentation basins is controlled by temporary outlet structure which is specifically designed to minimize the intrusion of sediment into the outlet from the temporary basin. Regular inspection of the temporary sedimentation basins will identify the need for sediment removal or cleaning of outlet devices to ensure proper operation. Symmes Maini & McKee Associates July

11 APPENDIX ONE HYDROLOGIC ANALYSIS Symmes Maini & McKee Associates July

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15 S Existing Subcatchment- (To UG Det.) S Existing Subcatchment- Overland MHD SB Existing Subcatchment B East MHD Land UP Existing Underground Recharge R S Existing Subcatchment- Overland East R Design Point Existing Offsite Flow Design Point Subcat Reach Pond Link Drainage Diagram for - Wheeler Road-Ex, Printed // HydroCAD. s/n HydroCAD Software Solutions LLC

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17 - Wheeler Road-Ex HydroCAD. s/n HydroCAD Software Solutions LLC Printed // Page Area (acres) Soil Group Soil Listing (selected nodes) Subcatchment Numbers. HSG A. HSG B S, SB, S. HSG C SB, S, S. HSG D S, SB, S. Other S. TOTAL AREA

18 - Wheeler Road-Ex HydroCAD. s/n HydroCAD Software Solutions LLC Type III -hr YR Rainfall=." Printed // Page Time span=.-. hrs, dt=. hrs, points Runoff by SCS TR- method, UH=SCS Reach routing by Stor-Ind+Trans method - Pond routing by Stor-Ind method Subcatchment S: Existing Subcatchment SB: Existing Subcatchment S: Existing Subcatchment S: Existing Runoff Area=, sf.% Impervious Runoff Depth=." Flow Length=' Tc=. min CN= Runoff=. cfs. af Runoff Area=, sf.% Impervious Runoff Depth=." Tc=. min CN= Runoff=. cfs. af Runoff Area=, sf.% Impervious Runoff Depth=." Tc=. min CN= Runoff=. cfs. af Runoff Area=. ac.% Impervious Runoff Depth=." Flow Length=,' Tc=. min CN= Runoff=. cfs. af Reach R: Design Point Avg. Flow Depth=.' Max Vel=. fps Inflow=. cfs. af." Round Pipe n=. L=.' S=. '/' Capacity=,. cfs Outflow=. cfs. af Reach R: Existing Offsite Flow Avg. Flow Depth=.' Max Vel=. fps Inflow=. cfs. af." Round Pipe n=. L=.' S=. '/' Capacity=,. cfs Outflow=. cfs. af Pond UP: Existing Underground Recharge Peak Elev=.' Storage=, cf Inflow=. cfs. af Outflow=. cfs. af Total Runoff Area =. ac Runoff Volume =. af Average Runoff Depth =.".% Pervious =. ac.% Impervious =. ac

19 - Wheeler Road-Ex HydroCAD. s/n HydroCAD Software Solutions LLC Type III -hr YR Rainfall=." Printed // Page Summary for Subcatchment S: Existing Subcatchment- Overland East Runoff =. hrs, Volume=. af, Depth=." Runoff by SCS TR- method, UH=SCS, Time Span=.-. hrs, dt=. hrs Type III -hr YR Rainfall=." Area (sf) CN Description, Woods, Good, HSG D, Brush, Fair, HSG D, Woods, Good, HSG B, Brush, Fair, HSG B, Weighted Average,.% Pervious Area Tc Length Slope Velocity Capacity Description (min) (feet) (ft/ft) (ft/sec) (cfs)... Sheet Flow, Sheet Flow Woods: Light underbrush n=. P=."... Shallow Concentrated Flow, SCF Woodland Kv=. fps... Shallow Concentrated Flow, SCF Woodland Kv=. fps... Shallow Concentrated Flow, SCF Woodland Kv=. fps. Total Subcatchment S: Existing Subcatchment- Overland East Hydrograph Runoff Flow (cfs). cfs Type III -hr YR Rainfall=." Runoff Area=, sf Runoff Volume=. af Runoff Depth=." Flow Length=' Tc=. min CN= Time (hours)

20 - Wheeler Road-Ex HydroCAD. s/n HydroCAD Software Solutions LLC Type III -hr YR Rainfall=." Printed // Page Summary for Subcatchment SB: Existing Subcatchment B East MHD Land [] Hint: Tc<dt may require smaller dt Runoff =. hrs, Volume=. af, Depth=." Runoff by SCS TR- method, UH=SCS, Time Span=.-. hrs, dt=. hrs Type III -hr YR Rainfall=." Area (sf) CN Description, Woods, Good, HSG B, Woods, Good, HSG C, Woods, Good, HSG D, Woods, Good, HSG C, Weighted Average,.% Pervious Area Tc Length Slope Velocity Capacity Description (min) (feet) (ft/ft) (ft/sec) (cfs). Direct Entry, Subcatchment SB: Existing Subcatchment B East MHD Land Hydrograph Runoff Flow (cfs). cfs Type III -hr YR Rainfall=." Runoff Area=, sf Runoff Volume=. af Runoff Depth=." Tc=. min CN= Time (hours)

21 - Wheeler Road-Ex HydroCAD. s/n HydroCAD Software Solutions LLC Type III -hr YR Rainfall=." Printed // Page Summary for Subcatchment S: Existing Subcatchment- (To UG Det.) [] Hint: Tc<dt may require smaller dt Runoff =. hrs, Volume=. af, Depth=." Runoff by SCS TR- method, UH=SCS, Time Span=.-. hrs, dt=. hrs Type III -hr YR Rainfall=." Area (sf) CN Description, Woods, Good, HSG C, >% Grass cover, Good, HSG C, Paved parking & roofs, Weighted Average,.% Pervious Area,.% Impervious Area Tc Length Slope Velocity Capacity Description (min) (feet) (ft/ft) (ft/sec) (cfs). Direct Entry, Subcatchment S: Existing Subcatchment- (To UG Det.) Hydrograph Flow (cfs). cfs Type III -hr YR Rainfall=." Runoff Area=, sf Runoff Volume=. af Runoff Depth=." Tc=. min CN= Runoff Time (hours)

22 - Wheeler Road-Ex HydroCAD. s/n HydroCAD Software Solutions LLC Type III -hr YR Rainfall=." Printed // Page Summary for Subcatchment S: Existing Subcatchment- Overland MHD Runoff =. hrs, Volume=. af, Depth=." Runoff by SCS TR- method, UH=SCS, Time Span=.-. hrs, dt=. hrs Type III -hr YR Rainfall=." Area (ac) CN Description. Woods, Good, HSG C. Brush, Fair, HSG C. Woods, Good, HSG D. Brush, Fair, HSG B. Woods, Good, HSG B. Woods, Good, HSG C. Woods, Good, HSG B. Woods, Good, HSG D. Woods, Good, HSG C. Weighted Average..% Pervious Area Tc Length Slope Velocity Capacity Description (min) (feet) (ft/ft) (ft/sec) (cfs)... Sheet Flow, Sheet Flow Grass: Short n=. P=."... Shallow Concentrated Flow, Short Grass Pasture Kv=. fps... Shallow Concentrated Flow, Short Grass Pasture Kv=. fps.... Pipe Channel,." Round Area=. sf Perim=.' r=.' n=. Concrete pipe, straight & clean.... Pipe Channel,." Round Area=. sf Perim=.' r=.' n=. Concrete pipe, straight & clean., Total

23 - Wheeler Road-Ex HydroCAD. s/n HydroCAD Software Solutions LLC Type III -hr YR Rainfall=." Printed // Page Subcatchment S: Existing Subcatchment- Overland MHD Hydrograph Runoff Flow (cfs). cfs Type III -hr YR Rainfall=." Runoff Area=. ac Runoff Volume=. af Runoff Depth=." Flow Length=,' Tc=. min CN= Time (hours)

24 - Wheeler Road-Ex HydroCAD. s/n HydroCAD Software Solutions LLC Type III -hr YR Rainfall=." Printed // Page [] Hint: Inlet/Outlet conditions not evaluated Summary for Reach R: Design Point Inflow Area =. ac,.% Impervious, Inflow Depth =." for YR event Inflow =. hrs, Volume=. af Outflow =. hrs, Volume=. af, Atten= %, Lag=. min Routing by Stor-Ind+Trans method, Time Span=.-. hrs, dt=. hrs Max. Velocity=. fps, Min. Travel Time=. min Avg. Velocity =. fps, Avg. Travel Time=. min Peak Storage= hrs Average Depth at Peak Storage=.' Bank-Full Depth=.', Capacity at Bank-Full=,. cfs." Round Pipe n=. Length=.' Slope=. '/' Inlet Invert=.', Outlet Invert=.' Reach R: Design Point Hydrograph Flow (cfs). cfs. cfs Inflow Area=. ac Avg. Flow Depth=.' Max Vel=. fps." Round Pipe n=. L=.' S=. '/' Capacity=,. cfs Inflow Outflow Time (hours)

25 - Wheeler Road-Ex HydroCAD. s/n HydroCAD Software Solutions LLC Type III -hr YR Rainfall=." Printed // Page Summary for Reach R: Existing Offsite Flow Design Point [] Hint: Inlet/Outlet conditions not evaluated Inflow Area =. ac,.% Impervious, Inflow Depth =." for YR event Inflow =. hrs, Volume=. af Outflow =. hrs, Volume=. af, Atten= %, Lag=. min Routing by Stor-Ind+Trans method, Time Span=.-. hrs, dt=. hrs Max. Velocity=. fps, Min. Travel Time=. min Avg. Velocity =. fps, Avg. Travel Time=. min Peak Storage= hrs Average Depth at Peak Storage=.' Bank-Full Depth=.', Capacity at Bank-Full=,. cfs." Round Pipe n=. Length=.' Slope=. '/' Inlet Invert=.', Outlet Invert=.' Reach R: Existing Offsite Flow Design Point Hydrograph Flow (cfs). cfs. cfs Inflow Area=. ac Avg. Flow Depth=.' Max Vel=. fps." Round Pipe n=. L=.' S=. '/' Capacity=,. cfs Inflow Outflow Time (hours)

26 - Wheeler Road-Ex HydroCAD. s/n HydroCAD Software Solutions LLC Type III -hr YR Rainfall=." Printed // Page Summary for Pond UP: Existing Underground Recharge Inflow Area =. ac,.% Impervious, Inflow Depth =." for YR event Inflow =. hrs, Volume=. af Outflow =. hrs, Volume=. af, Atten= %, Lag=. min Primary =. hrs, Volume=. af Routing by Stor-Ind method, Time Span=.-. hrs, dt=. hrs Peak hrs Surf.Area=, sf Storage=, cf Plug-Flow detention time=. min calculated for. af (% of inflow) Center-of-Mass det. time=. min (. -. ) Volume Invert Avail.Storage Storage Description #.', cf Custom Stage Data (Pyramidal) Listed below Elevation Surf.Area Inc.Store Cum.Store Wet.Area (feet) (sq-ft) (cubic-feet) (cubic-feet) (sq-ft).,,.,,,, Device Routing Invert Outlet Devices # Primary.'." Vert. Orifice/Grate C=. # Primary.'." Vert. Orifice/Grate C=. Primary OutFlow Max=. hrs HW=.' (Free Discharge) =Orifice/Grate (Orifice Controls. fps) =Orifice/Grate ( Controls. cfs)

27 - Wheeler Road-Ex HydroCAD. s/n HydroCAD Software Solutions LLC Type III -hr YR Rainfall=." Printed // Page Pond UP: Existing Underground Recharge Hydrograph. cfs Inflow Area=. ac Peak Elev=.' Storage=, cf Inflow Primary Flow (cfs). cfs Time (hours)

28 - Wheeler Road-Ex Type III -hr YR Rainfall=." Printed // HydroCAD. s/n HydroCAD Software Solutions LLC Page Time span=.-. hrs, dt=. hrs, points Runoff by SCS TR- method, UH=SCS Reach routing by Stor-Ind+Trans method - Pond routing by Stor-Ind method Subcatchment S: Existing Subcatchment SB: Existing Subcatchment S: Existing Subcatchment S: Existing Runoff Area=, sf.% Impervious Runoff Depth=." Flow Length=' Tc=. min CN= Runoff=. cfs. af Runoff Area=, sf.% Impervious Runoff Depth=." Tc=. min CN= Runoff=. cfs. af Runoff Area=, sf.% Impervious Runoff Depth=." Tc=. min CN= Runoff=. cfs. af Runoff Area=. ac.% Impervious Runoff Depth=." Flow Length=,' Tc=. min CN= Runoff=. cfs. af Reach R: Design Point Avg. Flow Depth=.' Max Vel=. fps Inflow=. cfs. af." Round Pipe n=. L=.' S=. '/' Capacity=,. cfs Outflow=. cfs. af Reach R: Existing Offsite Flow Avg. Flow Depth=.' Max Vel=. fps Inflow=. cfs. af." Round Pipe n=. L=.' S=. '/' Capacity=,. cfs Outflow=. cfs. af Pond UP: Existing Underground Recharge Peak Elev=.' Storage=, cf Inflow=. cfs. af Outflow=. cfs. af Total Runoff Area =. ac Runoff Volume =. af Average Runoff Depth =.".% Pervious =. ac.% Impervious =. ac

29 - Wheeler Road-Ex Type III -hr YR Rainfall=." Printed // HydroCAD. s/n HydroCAD Software Solutions LLC Page Summary for Subcatchment S: Existing Subcatchment- Overland East Runoff =. hrs, Volume=. af, Depth=." Runoff by SCS TR- method, UH=SCS, Time Span=.-. hrs, dt=. hrs Type III -hr YR Rainfall=." Area (sf) CN Description, Woods, Good, HSG D, Brush, Fair, HSG D, Woods, Good, HSG B, Brush, Fair, HSG B, Weighted Average,.% Pervious Area Tc Length Slope Velocity Capacity Description (min) (feet) (ft/ft) (ft/sec) (cfs)... Sheet Flow, Sheet Flow Woods: Light underbrush n=. P=."... Shallow Concentrated Flow, SCF Woodland Kv=. fps... Shallow Concentrated Flow, SCF Woodland Kv=. fps... Shallow Concentrated Flow, SCF Woodland Kv=. fps. Total Subcatchment S: Existing Subcatchment- Overland East Hydrograph Flow (cfs). cfs Type III -hr YR Rainfall=." Runoff Area=, sf Runoff Volume=. af Runoff Depth=." Flow Length=' Tc=. min CN= Runoff Time (hours)

30 - Wheeler Road-Ex Type III -hr YR Rainfall=." Printed // HydroCAD. s/n HydroCAD Software Solutions LLC Page Summary for Subcatchment SB: Existing Subcatchment B East MHD Land [] Hint: Tc<dt may require smaller dt Runoff =. hrs, Volume=. af, Depth=." Runoff by SCS TR- method, UH=SCS, Time Span=.-. hrs, dt=. hrs Type III -hr YR Rainfall=." Area (sf) CN Description, Woods, Good, HSG B, Woods, Good, HSG C, Woods, Good, HSG D, Woods, Good, HSG C, Weighted Average,.% Pervious Area Tc Length Slope Velocity Capacity Description (min) (feet) (ft/ft) (ft/sec) (cfs). Direct Entry, Subcatchment SB: Existing Subcatchment B East MHD Land Hydrograph Flow (cfs). cfs Type III -hr YR Rainfall=." Runoff Area=, sf Runoff Volume=. af Runoff Depth=." Tc=. min CN= Runoff Time (hours)

31 - Wheeler Road-Ex Type III -hr YR Rainfall=." Printed // HydroCAD. s/n HydroCAD Software Solutions LLC Page Summary for Subcatchment S: Existing Subcatchment- (To UG Det.) [] Hint: Tc<dt may require smaller dt Runoff =. hrs, Volume=. af, Depth=." Runoff by SCS TR- method, UH=SCS, Time Span=.-. hrs, dt=. hrs Type III -hr YR Rainfall=." Area (sf) CN Description, Woods, Good, HSG C, >% Grass cover, Good, HSG C, Paved parking & roofs, Weighted Average,.% Pervious Area,.% Impervious Area Tc Length Slope Velocity Capacity Description (min) (feet) (ft/ft) (ft/sec) (cfs). Direct Entry, Subcatchment S: Existing Subcatchment- (To UG Det.) Hydrograph Flow (cfs). cfs Type III -hr YR Rainfall=." Runoff Area=, sf Runoff Volume=. af Runoff Depth=." Tc=. min CN= Runoff Time (hours)

32 - Wheeler Road-Ex Type III -hr YR Rainfall=." Printed // HydroCAD. s/n HydroCAD Software Solutions LLC Page Summary for Subcatchment S: Existing Subcatchment- Overland MHD Runoff =. hrs, Volume=. af, Depth=." Runoff by SCS TR- method, UH=SCS, Time Span=.-. hrs, dt=. hrs Type III -hr YR Rainfall=." Area (ac) CN Description. Woods, Good, HSG C. Brush, Fair, HSG C. Woods, Good, HSG D. Brush, Fair, HSG B. Woods, Good, HSG B. Woods, Good, HSG C. Woods, Good, HSG B. Woods, Good, HSG D. Woods, Good, HSG C. Weighted Average..% Pervious Area Tc Length Slope Velocity Capacity Description (min) (feet) (ft/ft) (ft/sec) (cfs)... Sheet Flow, Sheet Flow Grass: Short n=. P=."... Shallow Concentrated Flow, Short Grass Pasture Kv=. fps... Shallow Concentrated Flow, Short Grass Pasture Kv=. fps.... Pipe Channel,." Round Area=. sf Perim=.' r=.' n=. Concrete pipe, straight & clean.... Pipe Channel,." Round Area=. sf Perim=.' r=.' n=. Concrete pipe, straight & clean., Total

33 - Wheeler Road-Ex Type III -hr YR Rainfall=." Printed // HydroCAD. s/n HydroCAD Software Solutions LLC Page Subcatchment S: Existing Subcatchment- Overland MHD Hydrograph Flow (cfs). cfs Time (hours) Type III -hr YR Rainfall=." Runoff Area=. ac Runoff Volume=. af Runoff Depth=." Flow Length=,' Tc=. min CN= Runoff

34 - Wheeler Road-Ex Type III -hr YR Rainfall=." Printed // HydroCAD. s/n HydroCAD Software Solutions LLC Page [] Hint: Inlet/Outlet conditions not evaluated Summary for Reach R: Design Point Inflow Area =. ac,.% Impervious, Inflow Depth =." for YR event Inflow =. hrs, Volume=. af Outflow =. hrs, Volume=. af, Atten= %, Lag=. min Routing by Stor-Ind+Trans method, Time Span=.-. hrs, dt=. hrs Max. Velocity=. fps, Min. Travel Time=. min Avg. Velocity =. fps, Avg. Travel Time=. min Peak Storage= hrs Average Depth at Peak Storage=.' Bank-Full Depth=.', Capacity at Bank-Full=,. cfs." Round Pipe n=. Length=.' Slope=. '/' Inlet Invert=.', Outlet Invert=.' Reach R: Design Point Hydrograph Flow (cfs). cfs. cfs Inflow Area=. ac Avg. Flow Depth=.' Max Vel=. fps." Round Pipe n=. L=.' S=. '/' Capacity=,. cfs Inflow Outflow Time (hours)

35 - Wheeler Road-Ex Type III -hr YR Rainfall=." Printed // HydroCAD. s/n HydroCAD Software Solutions LLC Page Summary for Reach R: Existing Offsite Flow Design Point [] Hint: Inlet/Outlet conditions not evaluated Inflow Area =. ac,.% Impervious, Inflow Depth =." for YR event Inflow =. hrs, Volume=. af Outflow =. hrs, Volume=. af, Atten= %, Lag=. min Routing by Stor-Ind+Trans method, Time Span=.-. hrs, dt=. hrs Max. Velocity=. fps, Min. Travel Time=. min Avg. Velocity =. fps, Avg. Travel Time=. min Peak Storage= hrs Average Depth at Peak Storage=.' Bank-Full Depth=.', Capacity at Bank-Full=,. cfs." Round Pipe n=. Length=.' Slope=. '/' Inlet Invert=.', Outlet Invert=.' Reach R: Existing Offsite Flow Design Point Hydrograph Flow (cfs). cfs. cfs Time (hours) Inflow Area=. ac Avg. Flow Depth=.' Max Vel=. fps." Round Pipe n=. L=.' S=. '/' Capacity=,. cfs Inflow Outflow

36 - Wheeler Road-Ex Type III -hr YR Rainfall=." Printed // HydroCAD. s/n HydroCAD Software Solutions LLC Page Summary for Pond UP: Existing Underground Recharge Inflow Area =. ac,.% Impervious, Inflow Depth =." for YR event Inflow =. hrs, Volume=. af Outflow =. hrs, Volume=. af, Atten= %, Lag=. min Primary =. hrs, Volume=. af Routing by Stor-Ind method, Time Span=.-. hrs, dt=. hrs Peak hrs Surf.Area=, sf Storage=, cf Plug-Flow detention time=. min calculated for. af (% of inflow) Center-of-Mass det. time=. min (. -. ) Volume Invert Avail.Storage Storage Description #.', cf Custom Stage Data (Pyramidal) Listed below Elevation Surf.Area Inc.Store Cum.Store Wet.Area (feet) (sq-ft) (cubic-feet) (cubic-feet) (sq-ft).,,.,,,, Device Routing Invert Outlet Devices # Primary.'." Vert. Orifice/Grate C=. # Primary.'." Vert. Orifice/Grate C=. Primary OutFlow Max=. hrs HW=.' (Free Discharge) =Orifice/Grate (Orifice Controls. fps) =Orifice/Grate ( Controls. cfs)

37 - Wheeler Road-Ex Type III -hr YR Rainfall=." Printed // HydroCAD. s/n HydroCAD Software Solutions LLC Page Pond UP: Existing Underground Recharge Hydrograph. cfs Inflow Area=. ac Peak Elev=.' Storage=, cf Inflow Primary Flow (cfs). cfs Time (hours)

38 - Wheeler Road-Ex Type III -hr YR Rainfall=." Printed // HydroCAD. s/n HydroCAD Software Solutions LLC Page Time span=.-. hrs, dt=. hrs, points Runoff by SCS TR- method, UH=SCS Reach routing by Stor-Ind+Trans method - Pond routing by Stor-Ind method Subcatchment S: Existing Subcatchment SB: Existing Subcatchment S: Existing Subcatchment S: Existing Runoff Area=, sf.% Impervious Runoff Depth=." Flow Length=' Tc=. min CN= Runoff=. cfs. af Runoff Area=, sf.% Impervious Runoff Depth=." Tc=. min CN= Runoff=. cfs. af Runoff Area=, sf.% Impervious Runoff Depth=." Tc=. min CN= Runoff=. cfs. af Runoff Area=. ac.% Impervious Runoff Depth=." Flow Length=,' Tc=. min CN= Runoff=. cfs. af Reach R: Design Point Avg. Flow Depth=.' Max Vel=. fps Inflow=. cfs. af." Round Pipe n=. L=.' S=. '/' Capacity=,. cfs Outflow=. cfs. af Reach R: Existing Offsite Flow Avg. Flow Depth=.' Max Vel=. fps Inflow=. cfs. af." Round Pipe n=. L=.' S=. '/' Capacity=,. cfs Outflow=. cfs. af Pond UP: Existing Underground Peak Elev=.' Storage=, cf Inflow=. cfs. af Outflow=. cfs. af Total Runoff Area =. ac Runoff Volume =. af Average Runoff Depth =.".% Pervious =. ac.% Impervious =. ac

39 - Wheeler Road-Ex Type III -hr YR Rainfall=." Printed // HydroCAD. s/n HydroCAD Software Solutions LLC Page Summary for Subcatchment S: Existing Subcatchment- Overland East Runoff =. hrs, Volume=. af, Depth=." Runoff by SCS TR- method, UH=SCS, Time Span=.-. hrs, dt=. hrs Type III -hr YR Rainfall=." Area (sf) CN Description, Woods, Good, HSG D, Brush, Fair, HSG D, Woods, Good, HSG B, Brush, Fair, HSG B, Weighted Average,.% Pervious Area Tc Length Slope Velocity Capacity Description (min) (feet) (ft/ft) (ft/sec) (cfs)... Sheet Flow, Sheet Flow Woods: Light underbrush n=. P=."... Shallow Concentrated Flow, SCF Woodland Kv=. fps... Shallow Concentrated Flow, SCF Woodland Kv=. fps... Shallow Concentrated Flow, SCF Woodland Kv=. fps. Total Subcatchment S: Existing Subcatchment- Overland East Hydrograph Flow (cfs). cfs Type III -hr YR Rainfall=." Runoff Area=, sf Runoff Volume=. af Runoff Depth=." Flow Length=' Tc=. min CN= Runoff Time (hours)

40 - Wheeler Road-Ex Type III -hr YR Rainfall=." Printed // HydroCAD. s/n HydroCAD Software Solutions LLC Page Summary for Subcatchment SB: Existing Subcatchment B East MHD Land [] Hint: Tc<dt may require smaller dt Runoff =. hrs, Volume=. af, Depth=." Runoff by SCS TR- method, UH=SCS, Time Span=.-. hrs, dt=. hrs Type III -hr YR Rainfall=." Area (sf) CN Description, Woods, Good, HSG B, Woods, Good, HSG C, Woods, Good, HSG D, Woods, Good, HSG C, Weighted Average,.% Pervious Area Tc Length Slope Velocity Capacity Description (min) (feet) (ft/ft) (ft/sec) (cfs). Direct Entry, Subcatchment SB: Existing Subcatchment B East MHD Land Hydrograph Runoff Flow (cfs). cfs Type III -hr YR Rainfall=." Runoff Area=, sf Runoff Volume=. af Runoff Depth=." Tc=. min CN= Time (hours)

41 - Wheeler Road-Ex Type III -hr YR Rainfall=." Printed // HydroCAD. s/n HydroCAD Software Solutions LLC Page Summary for Subcatchment S: Existing Subcatchment- (To UG Det.) [] Hint: Tc<dt may require smaller dt Runoff =. hrs, Volume=. af, Depth=." Runoff by SCS TR- method, UH=SCS, Time Span=.-. hrs, dt=. hrs Type III -hr YR Rainfall=." Area (sf) CN Description, Woods, Good, HSG C, >% Grass cover, Good, HSG C, Paved parking & roofs, Weighted Average,.% Pervious Area,.% Impervious Area Tc Length Slope Velocity Capacity Description (min) (feet) (ft/ft) (ft/sec) (cfs). Direct Entry, Subcatchment S: Existing Subcatchment- (To UG Det.) Hydrograph Flow (cfs). cfs Type III -hr YR Rainfall=." Runoff Area=, sf Runoff Volume=. af Runoff Depth=." Tc=. min CN= Runoff Time (hours)

42 - Wheeler Road-Ex Type III -hr YR Rainfall=." Printed // HydroCAD. s/n HydroCAD Software Solutions LLC Page Summary for Subcatchment S: Existing Subcatchment- Overland MHD Runoff =. hrs, Volume=. af, Depth=." Runoff by SCS TR- method, UH=SCS, Time Span=.-. hrs, dt=. hrs Type III -hr YR Rainfall=." Area (ac) CN Description. Woods, Good, HSG C. Brush, Fair, HSG C. Woods, Good, HSG D. Brush, Fair, HSG B. Woods, Good, HSG B. Woods, Good, HSG C. Woods, Good, HSG B. Woods, Good, HSG D. Woods, Good, HSG C. Weighted Average..% Pervious Area Tc Length Slope Velocity Capacity Description (min) (feet) (ft/ft) (ft/sec) (cfs)... Sheet Flow, Sheet Flow Grass: Short n=. P=."... Shallow Concentrated Flow, Short Grass Pasture Kv=. fps... Shallow Concentrated Flow, Short Grass Pasture Kv=. fps.... Pipe Channel,." Round Area=. sf Perim=.' r=.' n=. Concrete pipe, straight & clean.... Pipe Channel,." Round Area=. sf Perim=.' r=.' n=. Concrete pipe, straight & clean., Total

43 - Wheeler Road-Ex Type III -hr YR Rainfall=." Printed // HydroCAD. s/n HydroCAD Software Solutions LLC Page Subcatchment S: Existing Subcatchment- Overland MHD Hydrograph Flow (cfs). cfs Time (hours) Type III -hr YR Rainfall=." Runoff Area=. ac Runoff Volume=. af Runoff Depth=." Flow Length=,' Tc=. min CN= Runoff

44 - Wheeler Road-Ex Type III -hr YR Rainfall=." Printed // HydroCAD. s/n HydroCAD Software Solutions LLC Page [] Hint: Inlet/Outlet conditions not evaluated Summary for Reach R: Design Point Inflow Area =. ac,.% Impervious, Inflow Depth =." for YR event Inflow =. hrs, Volume=. af Outflow =. hrs, Volume=. af, Atten= %, Lag=. min Routing by Stor-Ind+Trans method, Time Span=.-. hrs, dt=. hrs Max. Velocity=. fps, Min. Travel Time=. min Avg. Velocity =. fps, Avg. Travel Time=. min Peak Storage= hrs Average Depth at Peak Storage=.' Bank-Full Depth=.', Capacity at Bank-Full=,. cfs." Round Pipe n=. Length=.' Slope=. '/' Inlet Invert=.', Outlet Invert=.' Reach R: Design Point Hydrograph Flow (cfs). cfs. cfs Inflow Area=. ac Avg. Flow Depth=.' Max Vel=. fps." Round Pipe n=. L=.' S=. '/' Capacity=,. cfs Inflow Outflow Time (hours)

45 - Wheeler Road-Ex Type III -hr YR Rainfall=." Printed // HydroCAD. s/n HydroCAD Software Solutions LLC Page Summary for Reach R: Existing Offsite Flow Design Point [] Hint: Inlet/Outlet conditions not evaluated Inflow Area =. ac,.% Impervious, Inflow Depth =." for YR event Inflow =. hrs, Volume=. af Outflow =. hrs, Volume=. af, Atten= %, Lag=. min Routing by Stor-Ind+Trans method, Time Span=.-. hrs, dt=. hrs Max. Velocity=. fps, Min. Travel Time=. min Avg. Velocity =. fps, Avg. Travel Time=. min Peak Storage= hrs Average Depth at Peak Storage=.' Bank-Full Depth=.', Capacity at Bank-Full=,. cfs." Round Pipe n=. Length=.' Slope=. '/' Inlet Invert=.', Outlet Invert=.' Reach R: Existing Offsite Flow Design Point Hydrograph Flow (cfs). cfs. cfs Time (hours) Inflow Area=. ac Avg. Flow Depth=.' Max Vel=. fps." Round Pipe n=. L=.' S=. '/' Capacity=,. cfs Inflow Outflow

46 - Wheeler Road-Ex Type III -hr YR Rainfall=." Printed // HydroCAD. s/n HydroCAD Software Solutions LLC Page Summary for Pond UP: Existing Underground Recharge Inflow Area =. ac,.% Impervious, Inflow Depth =." for YR event Inflow =. hrs, Volume=. af Outflow =. hrs, Volume=. af, Atten= %, Lag=. min Primary =. hrs, Volume=. af Routing by Stor-Ind method, Time Span=.-. hrs, dt=. hrs Peak hrs Surf.Area=, sf Storage=, cf Plug-Flow detention time=. min calculated for. af (% of inflow) Center-of-Mass det. time=. min (. -. ) Volume Invert Avail.Storage Storage Description #.', cf Custom Stage Data (Pyramidal) Listed below Elevation Surf.Area Inc.Store Cum.Store Wet.Area (feet) (sq-ft) (cubic-feet) (cubic-feet) (sq-ft).,,.,,,, Device Routing Invert Outlet Devices # Primary.'." Vert. Orifice/Grate C=. # Primary.'." Vert. Orifice/Grate C=. Primary OutFlow Max=. hrs HW=.' (Free Discharge) =Orifice/Grate (Orifice Controls. fps) =Orifice/Grate (Orifice Controls. fps)

47 - Wheeler Road-Ex Type III -hr YR Rainfall=." Printed // HydroCAD. s/n HydroCAD Software Solutions LLC Page Pond UP: Existing Underground Recharge Hydrograph. cfs Inflow Area=. ac Peak Elev=.' Storage=, cf Inflow Primary Flow (cfs). cfs Time (hours)

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51 S S S S S S Off Site Access Road North Parking Area Northeast Parking Area Proposed Building Rooftop Tributary to Pond (south) SP Existing Subcatchment B East MHD Land R UP UP UP P S Design Point Existing Underground Recharge Proposed UG Recharge Proposed UG Recharge Detention Basin Tributary to Pond (NE) R (new Reach) P Existing Subcatchment- Overland MHD Subcat Reach Pond Link Routing Diagram for - Wheeler Road-Pr, Printed // HydroCAD.- s/n HydroCAD Software Solutions LLC

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53 - Wheeler Road-Pr HydroCAD.- s/n HydroCAD Software Solutions LLC Printed // Page Area (acres) Soil Group Subcatchment Numbers Soil Listing (all nodes). HSG A. HSG B SP, S, S, S, S, S. HSG C SP, P. HSG D S, SP, S, S, S, S, S. Other P, S, S, S. TOTAL AREA

54 - Wheeler Road-Pr Type III -hr YR Rainfall=." Printed // HydroCAD.- s/n HydroCAD Software Solutions LLC Page Time span=.-. hrs, dt=. hrs, points Runoff by SCS TR- method, UH=SCS, Weighted-CN Reach routing by Stor-Ind+Trans method - Pond routing by Stor-Ind method Subcatchment S: Off Site Subcatchment SP: Existing Runoff Area=, sf.% Impervious Runoff Depth=." Tc=. min CN= Runoff=. cfs. af Runoff Area=, sf.% Impervious Runoff Depth=." Tc=. min CN= Runoff=. cfs. af Subcatchment P: Existing Subcatchment- Runoff Area=. ac.% Impervious Runoff Depth=." Flow Length=,' Tc=. min CN= Runoff=. cfs. af Subcatchment S: North Parking Area Runoff Area=, sf.% Impervious Runoff Depth=." Tc=. min CN= Runoff=. cfs. af Subcatchment S: Northeast Parking AreaRunoff Area=, sf.% Impervious Runoff Depth=." Tc=. min CN= Runoff=. cfs. af Subcatchment S: Access Road Subcatchment S: Proposed Building Subcatchment S: Tributary to Pond Subcatchment S: Tributary to Pond Runoff Area=, sf.% Impervious Runoff Depth=." Tc=. min CN= Runoff=. cfs. af Runoff Area=, sf.% Impervious Runoff Depth=." Tc=. min CN= Runoff=. cfs. af Runoff Area=, sf.% Impervious Runoff Depth=." Tc=. min CN= Runoff=. cfs. af Runoff Area=, sf.% Impervious Runoff Depth=." Tc=. min CN= Runoff=. cfs. af Reach R: Design Point Avg. Flow Depth=.' Max Vel=. fps Inflow=. cfs. af." Round Pipe n=. L=.' S=. '/' Capacity=,. cfs Outflow=. cfs. af Reach R: (new Reach) Avg. Flow Depth=.' Max Vel=. fps Inflow=. cfs. af." Round Pipe n=. L=.' S=. '/' Capacity=,. cfs Outflow=. cfs. af Pond UP: Existing Underground Recharge Peak Elev=.' Storage=, cf Inflow=. cfs. af Outflow=. cfs. af Pond P: Detention Basin Pond UP: Proposed UG Recharge Pond UP: Proposed UG Recharge Peak Elev=.' Storage=, cf Inflow=. cfs. af Outflow=. cfs. af Peak Elev=.' Storage=, cf Inflow=. cfs. af Outflow=. cfs. af Peak Elev=.' Storage=, cf Inflow=. cfs. af Outflow=. cfs. af Total Runoff Area =. ac Runoff Volume =. af Average Runoff Depth =.".% Pervious =. ac.% Impervious =. ac

55 - Wheeler Road-Pr Type III -hr YR Rainfall=." Printed // HydroCAD.- s/n HydroCAD Software Solutions LLC Page [] Hint: Tc<dt may require smaller dt Summary for Subcatchment S: Off Site Runoff =. hrs, Volume=. af, Depth=." Runoff by SCS TR- method, UH=SCS, Weighted-CN, Time Span=.-. hrs, dt=. hrs Type III -hr YR Rainfall=." Area (sf) CN Description, >% Grass cover, Good, HSG D,.% Pervious Area Tc Length Slope Velocity Capacity Description (min) (feet) (ft/ft) (ft/sec) (cfs). Direct Entry, Subcatchment S: Off Site Hydrograph Runoff Flow (cfs). cfs Type III -hr YR Rainfall=." Runoff Area=, sf Runoff Volume=. af Runoff Depth=." Tc=. min CN= Time (hours)

56 - Wheeler Road-Pr Type III -hr YR Rainfall=." Printed // HydroCAD.- s/n HydroCAD Software Solutions LLC Page Summary for Subcatchment SP: Existing Subcatchment B East MHD Land [] Hint: Tc<dt may require smaller dt Runoff =. hrs, Volume=. af, Depth=." Runoff by SCS TR- method, UH=SCS, Weighted-CN, Time Span=.-. hrs, dt=. hrs Type III -hr YR Rainfall=." Area (sf) CN Description, Woods, Good, HSG B, Woods, Good, HSG C, Woods, Good, HSG D, Woods, Good, HSG C, Weighted Average,.% Pervious Area Tc Length Slope Velocity Capacity Description (min) (feet) (ft/ft) (ft/sec) (cfs). Direct Entry, Subcatchment SP: Existing Subcatchment B East MHD Land Hydrograph Runoff Flow (cfs). cfs Type III -hr YR Rainfall=." Runoff Area=, sf Runoff Volume=. af Runoff Depth=." Tc=. min CN= Time (hours)

57 - Wheeler Road-Pr Type III -hr YR Rainfall=." Printed // HydroCAD.- s/n HydroCAD Software Solutions LLC Page Summary for Subcatchment P: Existing Subcatchment- Overland MHD Runoff =. hrs, Volume=. af, Depth=." Runoff by SCS TR- method, UH=SCS, Weighted-CN, Time Span=.-. hrs, dt=. hrs Type III -hr YR Rainfall=." Area (ac) CN Description. Woods, Good, HSG C. Brush, Fair, HSG C. Woods, Good, HSG C *. IMPERVIOUS. Weighted Average..% Pervious Area..% Impervious Area Tc Length Slope Velocity Capacity Description (min) (feet) (ft/ft) (ft/sec) (cfs)... Sheet Flow, Sheet Flow Woods: Dense underbrush n=. P=."... Shallow Concentrated Flow, Forest w/heavy Litter Kv=. fps.... Pipe Channel,." Round Area=. sf Perim=.' r=.' n=. Concrete pipe, straight & clean.... Pipe Channel,." Round Area=. sf Perim=.' r=.' n=. Concrete pipe, straight & clean., Total

58 - Wheeler Road-Pr Type III -hr YR Rainfall=." Printed // HydroCAD.- s/n HydroCAD Software Solutions LLC Page Subcatchment P: Existing Subcatchment- Overland MHD Hydrograph Runoff Flow (cfs). cfs Type III -hr YR Rainfall=." Runoff Area=. ac Runoff Volume=. af Runoff Depth=." Flow Length=,' Tc=. min CN= Time (hours)

59 - Wheeler Road-Pr Type III -hr YR Rainfall=." Printed // HydroCAD.- s/n HydroCAD Software Solutions LLC Page [] Hint: Tc<dt may require smaller dt Summary for Subcatchment S: North Parking Area Runoff =. hrs, Volume=. af, Depth=." Runoff by SCS TR- method, UH=SCS, Weighted-CN, Time Span=.-. hrs, dt=. hrs Type III -hr YR Rainfall=." Area (sf) CN Description, Paved parking, HSG B, >% Grass cover, Good, HSG B, >% Grass cover, Good, HSG D, Weighted Average,.% Pervious Area,.% Impervious Area Tc Length Slope Velocity Capacity Description (min) (feet) (ft/ft) (ft/sec) (cfs). Direct Entry, Subcatchment S: North Parking Area Hydrograph Runoff Flow (cfs). cfs Type III -hr YR Rainfall=." Runoff Area=, sf Runoff Volume=. af Runoff Depth=." Tc=. min CN= Time (hours)

60 - Wheeler Road-Pr Type III -hr YR Rainfall=." Printed // HydroCAD.- s/n HydroCAD Software Solutions LLC Page Summary for Subcatchment S: Northeast Parking Area [] Hint: Tc<dt may require smaller dt Runoff =. hrs, Volume=. af, Depth=." Runoff by SCS TR- method, UH=SCS, Weighted-CN, Time Span=.-. hrs, dt=. hrs Type III -hr YR Rainfall=." Area (sf) CN Description *, All Impervious Area, >% Grass cover, Good, HSG D, >% Grass cover, Good, HSG B, Weighted Average,.% Pervious Area,.% Impervious Area Tc Length Slope Velocity Capacity Description (min) (feet) (ft/ft) (ft/sec) (cfs). Direct Entry, Direct Subcatchment S: Northeast Parking Area Hydrograph Runoff Flow (cfs). cfs Type III -hr YR Rainfall=." Runoff Area=, sf Runoff Volume=. af Runoff Depth=." Tc=. min CN= Time (hours)

61 - Wheeler Road-Pr Type III -hr YR Rainfall=." Printed // HydroCAD.- s/n HydroCAD Software Solutions LLC Page [] Hint: Tc<dt may require smaller dt Summary for Subcatchment S: Access Road Runoff =. hrs, Volume=. af, Depth=." Runoff by SCS TR- method, UH=SCS, Weighted-CN, Time Span=.-. hrs, dt=. hrs Type III -hr YR Rainfall=." Area (sf) CN Description, >% Grass cover, Good, HSG D,.% Pervious Area Tc Length Slope Velocity Capacity Description (min) (feet) (ft/ft) (ft/sec) (cfs). Direct Entry, Subcatchment S: Access Road Hydrograph Runoff Flow (cfs) cfs Type III -hr YR Rainfall=." Runoff Area=, sf Runoff Volume=. af Runoff Depth=." Tc=. min CN=... Time (hours)

62 - Wheeler Road-Pr Type III -hr YR Rainfall=." Printed // HydroCAD.- s/n HydroCAD Software Solutions LLC Page Summary for Subcatchment S: Proposed Building Rooftop [] Hint: Tc<dt may require smaller dt Runoff =. hrs, Volume=. af, Depth=." Runoff by SCS TR- method, UH=SCS, Weighted-CN, Time Span=.-. hrs, dt=. hrs Type III -hr YR Rainfall=." Area (sf) CN Description, Paved parking, HSG B,.% Impervious Area Tc Length Slope Velocity Capacity Description (min) (feet) (ft/ft) (ft/sec) (cfs). Direct Entry, Rooftop Runoff Subcatchment S: Proposed Building Rooftop Hydrograph Runoff Flow (cfs). cfs Type III -hr YR Rainfall=." Runoff Area=, sf Runoff Volume=. af Runoff Depth=." Tc=. min CN= Time (hours)

63 - Wheeler Road-Pr Type III -hr YR Rainfall=." Printed // HydroCAD.- s/n HydroCAD Software Solutions LLC Page Summary for Subcatchment S: Tributary to Pond (south) [] Hint: Tc<dt may require smaller dt Runoff =. hrs, Volume=. af, Depth=." Runoff by SCS TR- method, UH=SCS, Weighted-CN, Time Span=.-. hrs, dt=. hrs Type III -hr YR Rainfall=." Area (sf) CN Description, >% Grass cover, Good, HSG D, >% Grass cover, Good, HSG B *, All Impervious Surfaces, Weighted Average,.% Pervious Area,.% Impervious Area Tc Length Slope Velocity Capacity Description (min) (feet) (ft/ft) (ft/sec) (cfs). Direct Entry, Subcatchment S: Tributary to Pond (south) Hydrograph Flow (cfs). cfs Time (hours) Type III -hr YR Rainfall=." Runoff Area=, sf Runoff Volume=. af Runoff Depth=." Tc=. min CN= Runoff

64 - Wheeler Road-Pr Type III -hr YR Rainfall=." Printed // HydroCAD.- s/n HydroCAD Software Solutions LLC Page Summary for Subcatchment S: Tributary to Pond (NE) [] Hint: Tc<dt may require smaller dt Runoff =. hrs, Volume=. af, Depth=." Runoff by SCS TR- method, UH=SCS, Weighted-CN, Time Span=.-. hrs, dt=. hrs Type III -hr YR Rainfall=." Area (sf) CN Description, >% Grass cover, Good, HSG D, >% Grass cover, Good, HSG B *, All Impervious Surfaces, Weighted Average,.% Pervious Area,.% Impervious Area Tc Length Slope Velocity Capacity Description (min) (feet) (ft/ft) (ft/sec) (cfs). Direct Entry, Subcatchment S: Tributary to Pond (NE) Hydrograph Runoff Flow (cfs). cfs Type III -hr YR Rainfall=." Runoff Area=, sf Runoff Volume=. af Runoff Depth=." Tc=. min CN= Time (hours)