DRAINAGE REPORT FOR THORNTON SELF STORAGE THORNTON, COLORADO

Transcription

1 DRAINAGE REPORT FOR THORNTON SELF STORAGE THORNTON, COLORADO Prepared by: Bowman Consulting 603 Park Point Dr. Suite 100 Golden, CO (303) June 29, 2015 Revised August 14, 2015

2 CERTIFICATE SHEET DCB Construction hereby certifies that the drainage facilities for the Thornton Self-Storage will be constructed according to the design presented in this report. I understand that the City of Thornton does not and shall not assume liability for the drainage facilities designed and/or certified by my engineer. I understand that the City of Thornton reviews drainage plans but cannot, on behalf of Thornton Self-Storage, guarantee that final drainage design review will be absolve DCB Construction and/or their successors and/or assigns of future liability for improper design. I further understand that approval of the Plat and/or Development Permit does not imply approval of my engineer s drainage design. ATTEST: Name of Responsible Party Notary Public Authorized Signature I hereby certify that this report (plan) for the final drainage design of Thornton Self-Storage was prepared by me (or under my direct supervision) in accordance with the provisions of the City of Thornton Standards and Specifications for the Design and Construction of Public and Private Improvements for the Responsible Parties thereof. I understand that the City of Thornton does not and shall not assume liability for drainage facilities designed by others. Charles Edward Weiss Registered Professional Engineer State of Colorado No

3 GENERAL LOCATION AND DESCRIPTION The Thornton Self-Storage site is located in the Southeast Quarter of Section 34, Township 1 South, Range 68 West of the 6 th Principal Meridian and takes up approximately acre portion of Lot 1, Block 1, Qwest Thornton Central Office Subdivision on the west side of North Washington Street. The site s surrounding area is made up of commercial and industrial properties. There is a 40 foot right of way adjacent to the north property line that contains drainage pipes and will be replatted as a drainage easement. An existing STOR-N-LOCK facility is located on the other side of the right of way. The west side of the site is bounded by a day care facility and Newcomb Spring of Colorado manufacturing facility which front Pennsylvania Street. Qwest has a commercial building south of the site with a parking lot and detention basin adjacent to the property. The northeast corner of the site contains a gas regulator station that is in a 30 foot by 50 foot easement. Just west of the gas regulator station is a 42 inch storm drain which daylights into a grass lined channel in a 40 foot drainage easement that runs southeast from the north property line to the site s ultimate outfall, an existing 6 x 3 RCB that goes under Washington Street into Brantner Gulch. Currently the site is undeveloped and covered with sparse vegetation and native grasses. Proposed for the site is an eight building self-storage facility. The main building will be on the east side of the site near Washington Street. It is planned to be a two story structure with water and sewer services, climate-controlled, storage building, approximately 36,900 square feet. The other seven buildings will be single story structures for storage only ranging from approximately 6,000 to 12,000 square feet with driving lanes in between them. A detention and water quality facility is proposed just south of the main building. No irrigation facilities are proposed for this site. DRAINAGE BASINS AND SUB-BASINS The project area was included in the Flood Insurance Rate Map (FIRM) for Adams County, Panel No C0311 H, revised March 5, The site does not lie within a Flood Hazard Area as designated by the FIRM. A copy of the FIRM is included at the back of this report. The site drains under Washington Street to Brantner Gulch. The gulch flows easterly to the South Platte River. The South Platte is located about five miles east of the site. The site area does not lie within a major basin study area. Historically, the site generally sloped from southwest to northeast at a uniform 2% towards Washington Street. This historic drainage pattern will not be altered by the proposed additions.

4 The area was divided into six major drainage basins, five offsite (OS) and the onsite basin which consist of four sub-basins, converging at the culvert crossing under Washington Street. The offsite basins encompass 57.5 acres of commercial/industrial properties, streets, and open space. Areas south of 120 th Avenue are in the City of Northglenn. Pam Acre, Northglenn s Floodplain Administration Stormwater Coordinator, stated that runoff south of 120 th Ave and east of the Farmers Highline Canal is intercepted in piping and directed east along 120 th Ave until they turn north at Race Street and discharge into Brantner Gulch. Basin OS1 includes sub-basins A-J, N-P, R and S as seen in the appendix and starts on the north side of 120 th Ave at the Farmers Highline Canal then continues all the way down Pennsylvania Street, collecting flow from commercial properties on the west side of Pennsylvania Street, to the intersection of Washington Street. Minor flows are collected in a series of inlets as described in the following sentences, major flows continue to Washington Street. There the flow turns south to be collected in the inlets at the culvert on the east side of the Thornton Self-Storage facility crossing Washington Street (design point #3). There are inlets located approximately two thirds of the way down Pennsylvania Street (design point #1) that given the pipe size and slope can only handle the 5 year storm event interception and piped north of the day care site into the storm sewer within the 40 foot Right of Way along the north side of the project site. Another set of inlets located on Pennsylvania Street approximately 275 feet west of the intersection with Washington Street (design point #2) are also sized to pick up the 5 year flow given the pipe size and slope at that point. That flow is piped south through the STOR-N-LOC property where it ties into the existing drainage system in the 40 foot Right of Way. These inlets are located in the sump of Pennsylvania Street. Basin OS2 is located directly north of the Thornton Self Storage Site and consist of the drainage from the STOR-N-LOC facility, which flows to their detention basin on the east side of their site and is piped to the 42 inch drainage pipe located in the 40 foot Right of Way near the gas regulator station (design point #6). For the purpose of calculations this area is called sub-basin Q in the appendix of this report. Basin OS3 is located south of the Thornton Self Storage Site and is made up of sub-basins T-W, beginning at the intersection of 120 th Ave and Pennsylvania Street and continues along the north side of 120 th Ave moving east and including the commercial sites north of 120 th Ave. It then turns north at Washington Street, picking up flow from the west side of the street and continues north to the inlets at the existing 6 X 3 concrete box culvert to cross Washington Street (design point #4). There is an inlet on the west side of Washington Street before the first intersection that picks up the 5 year flow to that point and pipes the flow through a 24 inch RCP out falling into the open channel at the entrance to the 6 X 3 concrete box culvert. Basin OS4 is the adjacent Qwest property that was made up of four sub-basins in their drainage report. OS4-1 s flow is directed into the Qwest detention basin which is then piped across the Self-Storage site to the channel opening at the Washington Street box culvert crossing (design point #6). OS4-2 s flow goes out the south drive access and into Washington Street. Flow in area OS4-3 is channeled to a culvert opening that ties into the existing storm system in Washington Street Right of Way. OS4-4 follows the historical flow path to the northeast corner of the parking

5 lot and through a curb opening onto the Self-Storage site. For the purpose of this report the site was broken into sub-basins Y and Z. Basin OS5 includes three commercial sites, sub-basins K-L on the Historic Drainage exhibit in the appendix, on the east side of Pennsylvania Street along with open space, sub-basin X, south of the first commercial site that extends along the back of the commercial sites down to the Self- Storage site (design point #5). The commercial sites have onsite detention that releases to a channel flowing along the west side of the Self-Storage property, then continue around the north side of the Self-Storage site joining with the 42 inch RCP flow in the channel leading to the box culvert under Washington Street (design point #6). Basin A is the onsite basin which is broken into seven sub-basins, A1 through A7. The existing site consists of native vegetation. A1 consist of the majority of the development portion of the site including storage buildings and drive aisles, A2 is the north drive aisle which eventually enters A3 through a curb opening near the northern access point. A3 is the green space at the front of the site near Washington Street. Sub-basin A4 includes the main access point on the south eastern side of the site along with the main building parking area and the disturbed area added to the Qwest parking lot. A5 is the detention pond. A6 and A7 are areas outside the development area where flow will be undisturbed. More details and specifics will be explained in the drainage facility design portion of this report. DRAINAGE DESIGN CRITERIA The drainage plan is designed in accordance to the City of Thornton Standards and Specifications for the Design and Construction of Public Improvements, revised October 2012 and Urban Drainage and Flood Control District Criteria Manual Volume 1 and Criteria Manual Volume 2, revised April Procedures for estimating storm runoff are those described in the manuals above. Anderson and Hastings prepared a drainage study for the Qwest site titled Qwest Thornton Exchange Expansion which included the Self-Storage site. The east side of the site has many constraints including Washington Street, utilities along Washington Street, the gas regulator station, and converging drainage systems. The rainfall distribution values were found in table of the City of Thornton Standards and Specifications. The rational method was used since the site area was less than 160 acres. Runoff values were determined for the 5-year initial storm and 100-year major storm event. Runoff coefficients were taken from tables RO-3 and RO-5 in the Urban Drainage and Flood Control District, weighting global values based on percentage of land use type. Detention volumes were determined along with the allowable release rates for both the 5-year and 100-year storms per Urban Drainage and Flood Control District spreadsheets which can be viewed in the appendix of this report. Bentley FlowMaster V8i was used to determine pipe capacity, channel capacity, pipe size, and normal depth in the pipe. The reports for these pipes can be found in the appendix of this report.

6 WETLAND PRESERVATOIN AND MITIGATION There is no evidence of any wetlands present on the site. DRAINAGE FACILITY DESIGN The 10-year and 100-year detention basin discharge through the outlet pipe will be 0.85 cfs and 4.88 cfs respectively. To determine these discharge rates Urban Drainage and Flood Control table SO-1 was used for Hydrologic Soil Group C for the on-site Platner loam soils found in the NRCS web soil survey. The site is currently undeveloped open space that is 2% impervious and therefore requires a 10-year and 100-year volume of 0.41 and 0.76 acre feet. respectively. The detention basin will be constructed with 4 to 1 maximum side slopes. Volume provided for water quality is 0.16 acre feet. An emergency outlet sized for twice the 100-year outlet rate will be notched into the berm on the northeast side of the basin. The emergency outlet will be armored with Type L rip-rap. Grading will be accomplished by having a ridge line along the north side of the buildings. Flow will travel south in the drive aisles between the buildings to the curb and gutter in the south access drive, eventually passing through a curb opening into the detention pond. The flow north of the buildings will travel east along the north access drive curb and gutter to a curb opening to the green space at the east side of the site. This flow will join with the flow from that green space and be piped to the detention pond. The main access at the southeast corner of the site will convey flow through a curb opening at the detention pond. Undisturbed areas along the north and south side of the property will continue their historical flow to the east. The site has a 5-year and 100-year runoff rate of 9.9 and 22.3 cfs respectively. This flow will follow the historical path, sheet flowing from west to east across the site. The northern flow will enter a curb opening just east of the first building. From there it will travel over grass to an area inlet and piped to the detention pond. Flow on the south side of the property will flow to a curb opening and enter the detention pond. Flow from Basin OS5 was determined to be 16.3 and 35.2 cfs for the 5-year and 100-year, respectively. This flow will be collected in a culvert opening on the west side of the property and piped along the north side of the property to the culvert under Washington Street. CONCULSIONS The drainage plan was designed in accordance with City of Thornton Standard and Specifications. Calculations for the determination of runoff rates and volumes are included in the appendix of this report. The calculations were performed in accordance to the Thornton Standards and procedures given in the UDFCD Manual. A detention basin is provided to limit the runoff from the developed site so that there will be no impact on the downstream drainage facilities.

7 REFERENCES Standards and Specifications for the Design and Construction of Public Improvements, City of Thornton, 2012 Edition Urban Storm Drainage Criteria Manual (Volumes 1 & 2), Urban Drainage and Flood Control District, Denver, Colorado, June 2001 (with current revisions) Phase III Drainage Report, Anderson & Hastings on behalf of Qwest, Denver, Colorado, June 2000

8 APPENDIX

9 603 Park Point Drive, Suite 100 Golden, CO 80401

10 Table A-2 Off-Site C Value Calculations Self-Storage Thornton, Colorado Global Parameters 1 total park/open % pave/build % % check composite Imp. Land Use % Imp. C 2 C 5 C 100 Basin OS % % 88.74% Low Density Residential Basin OS % % 90.20% Medium Density Residential Basin OS % % 89.79% Multi-Family BasinOS % % 57.57% Parks/Open Space Basin OS % % 49.71% Pavement/Building Basin A % % 2.00% Subbasin Total Area (acres) Land Use Area per Sub-Basin C Coefficient 2 Residential Parks/Open Space Pavement/Building Composite Imperviousness Low Density Medium Density Multi-Family % Check 2-year 5-year 100-year Area (acres) % Area (acres) % Area (acres) % Area (acres) % Area (acres) % % % 0 0.0% % % % 90% % % 0 0.0% % % % 90% % % 0 0.0% % % % 51% % % 0 0.0% % % % 90% % % 0 0.0% % % % 90% % % 0 0.0% % % % 90% % % 0 0.0% % % % 90% % % 0 0.0% % % % 90% % % 0 0.0% % % % 90% % % 0 0.0% % % % 100% % % 0 0.0% % % % 90% % % 0 0.0% % % % 90% % % 0 0.0% % % % 90% % % 0 0.0% % % % 90% % % 0 0.0% % % % 90% % % 0 0.0% % % % 90% % % 0 0.0% % % % 90% % % 0 0.0% % % % 90% % % 0 0.0% % % % 90% % % 0 0.0% % % % 90% % % 0 0.0% % % % 90% % % 0 0.0% % % % 100% % % 0 0.0% % % % 71% % % 0 0.0% % % % 2% % % 0 0.0% % % % 76% % % 0 0.0% % % % 2% % % 0 0.0% % % % 2% Total % % % % % 72.33% 66% From Table RO-3 and RO-5 in the UDFCD USDCM 2. C coefficients calculated by weighting global C values based on percentage of land use type.

11 Table A-3 Off-Site Rational Method Hydrologic Calculations Thornton Self-Storage Thornton, Colorado Sub-Basin Data C Values 2-year 5-year 100-year Time of Concentration, Tc Overland Time (ti) Travel Time (tt) Tc Tc Check Final Tc Intensity, I Peak Discharge, Q Design Pt. Basin ID Area C CA C CA C CA Length (300' max) Slope ti Length Slope Velocity tt tc=ti+tt Total length Tc = (l/180+10) Final Tc 2-year 5-year 100-year 2-year 5-year 100-year acres ft % min. ft % fps min min ft min min in/hr cfs A % % B % % C % % D % % E % % F % % G % % H % % I % % J % % K % % L % % M % % N % % O % % P % % Q % % R % % S % % T % % U % % V % % W % % X % % site % % Y % % Z % % Total Thornton Self-Storage Offsite Hydrology xls Q Peak 1 of 1

12 WASHINGTON STREET 48" RCP EX. 18" RCP 54" RCP 603 Park Point Drive, Suite 100 Golden, CO 80401

13 Table A-2 On-Site C Value Calculations Self-Storage Thornton, Colorado Global Parameters 1 Land Use % Imp. C 2 C 5 C 100 Low Density Residential Medium Density Residential Multi-Family Parks/Open Space Pavement/Building Subbasin Land Use Area per Sub-Basin C Coefficient 2 Total Area Residential Parks/Open Space Pavement/Building Composite Imperviousness (acres) Low Density Medium Density Multi-Family % Check 2-year 5-year 100-year Area (acres) % Area (acres) % Area (acres) % Area (acres) % Area (acres) % A % % 0 0.0% % % % 100% A % % 0 0.0% % % % 100% A % % 0 0.0% % % % 4% A % % 0 0.0% % % % 100% A % % 0 0.0% % % % 2% A % % 0 0.0% % % % 2% A % % 0 0.0% % % % 2% Total % % % % % % 81% From Table RO-3 and RO-5 in the UDFCD USDCM 2. C coefficients calculated by weighting global C values based on percentage of land use type.

14 Table A-3 On-Site Rational Method Hydrologic Calculations Thornton Self-Storage Thornton, Colorado Sub-Basin Data C Values 2-year 5-year 100-year Time of Concentration, Tc Overland Time (ti) Travel Time (tt) Tc Tc Check Final Tc Intensity, I Peak Discharge, Q Design Pt. Basin ID Area C CA C CA C CA Length (300' max) Slope Length Slope ti tt acres ft % min. ft % fps min min ft min min in/hr cfs Velocity tc=ti+tt Total length Tc = (l/180+10) Final Tc 2-year 5-year 100-year 2-year 5-year 100-year 1 A % % A % % A % % A % % A % % A % % A % % TOTAL Thornton Self-Storage Site Hydrology xls Q Peak 2 of 2

15 DETENTION VOLUME BY THE MODIFIED FAA METHOD (See USDCM Volume 2 Storage Chapter for description of method) Project: THORNTON SELF-STORAGE Basin ID: ON SITE FLOW Design Information (Input): Design Information (Input): Catchment Drainage Imperviousness I a = percent Catchment Drainage Imperviousness I a = percent Catchment Drainage Area A = acres Catchment Drainage Area A = acres Predevelopment NRCS Soil Group Type = B A, B, C, or D Predevelopment NRCS Soil Group Type = B A, B, C, or D Return Period for Detention Control T = 10 years (2, 5, 10, 25, 50, or 100) Return Period for Detention Control T = 100 years (2, 5, 10, 25, 50, or 100) Time of Concentration of Watershed Tc = 13 minutes Time of Concentration of Watershed Tc = 13 minutes Allowable Unit Release Rate q = 0.23 cfs/acre Allowable Unit Release Rate q = 1.00 cfs/acre One-hour Precipitation P 1 = 0.97 inches One-hour Precipitation P 1 = 2.69 inches Design Rainfall IDF Formula i = C 1* P 1/(C 2+T c)^c 3 Design Rainfall IDF Formula i = C 1* P 1/(C 2+T c)^c 3 Coefficient One C 1 = Coefficient One C 1 = Coefficient Two C 2 = 10 Coefficient Two C 2 = 10 Coefficient Three C 3 = Coefficient Three C 3 = Determination of Average Outflow from the Basin (Calculated): (For catchments less than 160 acres only. For larger catchments, use hydrograph routing method) (NOTE: for catchments larger than 90 acres, CUHP hydrograph and routing are recommended) Determination of MINOR Detention Volume Using Modified FAA Method Determination of MAJOR Detention Volume Using Modified FAA Method Determination of Average Outflow from the Basin (Calculated): Runoff Coefficient C = 0.64 Runoff Coefficient C = 0.71 Inflow Peak Runoff Qp-in = 7.38 cfs Inflow Peak Runoff Qp-in = cfs Allowable Peak Outflow Rate Qp-out = 1.12 cfs Allowable Peak Outflow Rate Qp-out = 4.88 cfs Mod. FAA Minor Storage Volume = 8,912 cubic feet Mod. FAA Major Storage Volume = 23,062 cubic feet Mod. FAA Minor Storage Volume = acre-ft Mod. FAA Major Storage Volume = acre-ft 10 <- Enter Rainfall Duration Incremental Increase Value Here (e.g. 5 for 5-Minutes) Rainfall Rainfall Inflow Adjustment Average Outflow Storage Rainfall Rainfall Inflow Adjustment Average Outflow Storage Duration Intensity Volume Factor Outflow Volume Volume Duration Intensity Volume Factor Outflow Volume Volume minutes inches / hr cubic feet "m" cfs cubic feet cubic feet minutes inches / hr cubic feet "m" cfs cubic feet cubic feet (input) (output) (output) (output) (output) (output) (output) (input) (output) (output) (output) (output) (output) (output) , , , ,928 12, , ,098 5, , ,773 17, , ,434 7, , ,237 19, , ,771 7, , ,701 21, , ,108 8, , ,165 22, , ,445 8, , ,629 22, , ,781 8, , ,093 23, , ,118 8, , ,557 23, , ,455 8, , ,021 22, , ,791 8, , ,485 22, , ,128 8, , ,949 22, , ,465 8, , ,413 21, , ,802 8, , ,877 21, , ,138 8, , ,341 20, , ,475 8, , ,805 19, , ,812 8, , ,269 19, , ,149 8, , ,733 18, , ,485 8, , ,197 17, , ,822 8, , ,661 16, , ,159 8, , ,125 15, , ,495 7, , ,589 14, , ,832 7, , ,053 13, , ,169 7, , ,517 13, , ,506 7, , ,981 12, , ,842 7, , ,445 11, , ,179 7, , ,909 10, , ,516 6, , ,373 9, , ,852 6, , ,837 8, , ,189 6, , ,301 7, , ,526 6, , ,765 5, , ,863 6, , ,229 4, , ,199 5, , ,693 3, , ,536 5, , ,157 2, , ,873 5, , ,621 1, , ,209 5, , , , ,546 5, , , , ,883 4, , ,013-1, , ,220 4, , ,477-2, , ,556 4, , ,941-3, , ,893 4, , ,405-5, , ,230 3, , ,869-6, , ,567 3, , ,333-7, , ,903 3, , ,797-8, , ,240 3, , ,261-9, , ,577 2, , ,725-10, , ,913 2, , ,189-12, , ,250 2, , ,653-13, , ,587 2, , ,117-14, , ,924 1, , ,581-15, , ,260 1, , ,045-16, , ,597 1, , ,509-18, , ,934 1, , ,973-19, , , , ,437-20, , , , ,901-21, , , , ,365-22, , , , ,829-24, , , , ,293-25, , , , ,757-26, , , , ,221-27, , , , ,685-29,018 Mod. FAA Minor Storage Volume (cubic ft.) = 8,912 Mod. FAA Major Storage Volume (cubic ft.) = 23,062 Mod. FAA Minor Storage Volume (acre-ft.) = Mod. FAA Major Storage Volume (acre-ft.) = UDFCD DETENTION VOLUME ESTIMATING WORKBOOK Version 2.2, Released January 2010 Modified FAA Method.xls, Modified FAA 8/13/2015, 3:54 PM

16 DETENTION VOLUME BY THE MODIFIED FAA METHOD (See USDCM Volume 2 Storage Chapter for description of method) Project: THORNTON SELF-STORAGE Basin ID: ON SITE FLOW Inflow and Outflow Volumes vs. Rainfall Duration 100,000 80,000 60,000 Volume (Cubic Feet) 40,000 20, ,000-40,000 Duration (Minutes) Minor Storm Inflow Volume Minor Storm Outflow Volume Minor Storm Storage Volume Major Storm Inflow Volume Major Storm Outflow Volume Major Storm Storage Volume UDFCD DETENTION VOLUME ESTIMATING WORKBOOK Version 2.2, Released January 2010 Modified FAA Method.xls, Modified FAA 8/13/2015, 3:54 PM

17 Detention Summary Thornton Self-Storage Detention Basin Basin 1 Contributing Area, Acres 4.88 Bottom Elevation 5330 Overflow Elevation 5335 Basin Depth, ft. 5.0 WQCV, cf 5, year WSE Year Depth, ft year Volume, cf 16, year Peak Outflow, cfs year WSE Year Depth, ft year Volume, cf 36, year Peak Outflow, cfs 4.88 Total Provided: WQCV, cf 7, Year, cf 18, Year, cf 33,569 Total Required: WQCV, cf 5, Year, cf 15, Year, cf 30,114

18 INLET IN A SUMP OR SAG LOCATION Project = Inlet ID = THORNTON SELF-STORAGE WASHINGTON SUMP H-Curb W W P H-Vert Lo (C) Wo Lo (G) Design Information (Input) MINOR MAJOR Type of Inlet Inlet Type = CDOT Type R Curb Opening Local Depression (additional to continuous gutter depression 'a' from 'Q-Allow') a local = inches Number of Unit Inlets (Grate or Curb Opening) No = 1 1 Water Depth at Flowline (outside of local depression) Ponding Depth = inches Grate Information MINOR MAJOR Override Depths Length of a Unit Grate L o (G) = N/A N/A feet Width of a Unit Grate W o = N/A N/A feet Area Opening Ratio for a Grate (typical values ) A ratio = N/A N/A Clogging Factor for a Single Grate (typical value ) C f (G) = N/A N/A Grate Weir Coefficient (typical value ) C w (G) = N/A N/A Grate Orifice Coefficient (typical value ) C o (G) = N/A N/A Curb Opening Information MINOR MAJOR Length of a Unit Curb Opening L o (C) = feet Height of Vertical Curb Opening in Inches H vert = inches Height of Curb Orifice Throat in Inches H throat = inches Angle of Throat (see USDCM Figure ST-5) Theta = degrees Side Width for Depression Pan (typically the gutter width of 2 feet) W p = feet Clogging Factor for a Single Curb Opening (typical value 0.10) C f (C) = Curb Opening Weir Coefficient (typical value ) C w (C) = Curb Opening Orifice Coefficient (typical value ) C o (C) = MINOR MAJOR Total Inlet Interception Capacity (assumes clogged condition) Q a = cfs WARNING: Inlet Capacity less than Q Peak for Minor and Major Storms Q PEAK REQUIRED = cfs Washington 100yr Sump Inlet.xlsm, Inlet In Sump 8/14/2015, 1:16 PM

19 Worksheet for commercial site 100yr inlet pipe Project Description Friction Method Solve For Manning Formula Full Flow Diameter Input Data Roughness Coefficient Channel Slope % Normal Depth 2.40 ft Diameter in Discharge ft³/s Results Diameter in Normal Depth 2.40 ft Flow Area 4.51 ft² Wetted Perimeter 7.53 ft Hydraulic Radius 0.60 ft Top Width 0.00 ft Critical Depth 2.05 ft Percent Full % Critical Slope ft/ft Velocity 8.12 ft/s Velocity Head 1.02 ft Specific Energy 3.42 ft Froude Number 0.00 Maximum Discharge ft³/s Discharge Full ft³/s Slope Full ft/ft Flow Type SubCritical GVF Input Data Downstream Depth 0.00 ft Length 0.00 ft Number Of Steps 0 GVF Output Data Upstream Depth 0.00 ft Profile Description Profile Headloss 0.00 ft Average End Depth Over Rise 0.00 % 8/14/ :05:04 AM Bentley Systems, Inc. Haestad Methods Solution Bentley Center FlowMaster V8i (SELECTseries 1) [ ] 27 Siemons Company Drive Suite 200 W Watertown, CT USA Page 1 of 2

20 Worksheet for commercial site 100yr inlet pipe GVF Output Data Normal Depth Over Rise % Downstream Velocity Infinity ft/s Upstream Velocity Infinity ft/s Normal Depth 2.40 ft Critical Depth 2.05 ft Channel Slope % Critical Slope ft/ft 8/14/ :05:04 AM Bentley Systems, Inc. Haestad Methods Solution Bentley Center FlowMaster V8i (SELECTseries 1) [ ] 27 Siemons Company Drive Suite 200 W Watertown, CT USA Page 2 of 2

21 Worksheet for commercial site 5yr inlet pipe Project Description Friction Method Solve For Manning Formula Full Flow Diameter Input Data Roughness Coefficient Channel Slope % Normal Depth 1.79 ft Diameter in Discharge ft³/s Results Diameter in Normal Depth 1.79 ft Flow Area 2.52 ft² Wetted Perimeter 5.63 ft Hydraulic Radius 0.45 ft Top Width 0.00 ft Critical Depth 1.51 ft Percent Full % Critical Slope ft/ft Velocity 6.69 ft/s Velocity Head 0.70 ft Specific Energy 2.49 ft Froude Number 0.00 Maximum Discharge ft³/s Discharge Full ft³/s Slope Full ft/ft Flow Type SubCritical GVF Input Data Downstream Depth 0.00 ft Length 0.00 ft Number Of Steps 0 GVF Output Data Upstream Depth 0.00 ft Profile Description Profile Headloss 0.00 ft Average End Depth Over Rise 0.00 % 8/14/ :24:29 AM Bentley Systems, Inc. Haestad Methods Solution Bentley Center FlowMaster V8i (SELECTseries 1) [ ] 27 Siemons Company Drive Suite 200 W Watertown, CT USA Page 1 of 2

22 Worksheet for commercial site 5yr inlet pipe GVF Output Data Normal Depth Over Rise % Downstream Velocity Infinity ft/s Upstream Velocity Infinity ft/s Normal Depth 1.79 ft Critical Depth 1.51 ft Channel Slope % Critical Slope ft/ft 8/14/ :24:29 AM Bentley Systems, Inc. Haestad Methods Solution Bentley Center FlowMaster V8i (SELECTseries 1) [ ] 27 Siemons Company Drive Suite 200 W Watertown, CT USA Page 2 of 2

23 Project Description Worksheet for 5yr Penn Plus 100yr Commercial Friction Method Solve For Manning Formula Full Flow Diameter Input Data Roughness Coefficient Channel Slope % Normal Depth 3.49 ft Diameter in Discharge ft³/s Results Diameter in Normal Depth 3.49 ft Flow Area 9.56 ft² Wetted Perimeter ft Hydraulic Radius 0.87 ft Top Width 0.00 ft Critical Depth 2.64 ft Percent Full % Critical Slope ft/ft Velocity 7.41 ft/s Velocity Head 0.85 ft Specific Energy 4.34 ft Froude Number 0.00 Maximum Discharge ft³/s Discharge Full ft³/s Slope Full ft/ft Flow Type SubCritical GVF Input Data Downstream Depth 0.00 ft Length 0.00 ft Number Of Steps 0 GVF Output Data Upstream Depth 0.00 ft Profile Description Profile Headloss 0.00 ft Average End Depth Over Rise 0.00 % 8/14/ :02:29 AM Bentley Systems, Inc. Haestad Methods Solution Bentley Center FlowMaster V8i (SELECTseries 1) [ ] 27 Siemons Company Drive Suite 200 W Watertown, CT USA Page 1 of 2

24 Worksheet for 5yr Penn Plus 100yr Commercial GVF Output Data Normal Depth Over Rise % Downstream Velocity Infinity ft/s Upstream Velocity Infinity ft/s Normal Depth 3.49 ft Critical Depth 2.64 ft Channel Slope % Critical Slope ft/ft 8/14/ :02:29 AM Bentley Systems, Inc. Haestad Methods Solution Bentley Center FlowMaster V8i (SELECTseries 1) [ ] 27 Siemons Company Drive Suite 200 W Watertown, CT USA Page 2 of 2

25 Project Description Worksheet for 5yr Penn Plus 5yr Commercial Friction Method Solve For Manning Formula Full Flow Diameter Input Data Roughness Coefficient Channel Slope % Normal Depth 3.09 ft Diameter in Discharge ft³/s Results Diameter in Normal Depth 3.09 ft Flow Area 7.48 ft² Wetted Perimeter 9.70 ft Hydraulic Radius 0.77 ft Top Width 0.00 ft Critical Depth 2.31 ft Percent Full % Critical Slope ft/ft Velocity 6.83 ft/s Velocity Head 0.72 ft Specific Energy 3.81 ft Froude Number 0.00 Maximum Discharge ft³/s Discharge Full ft³/s Slope Full ft/ft Flow Type SubCritical GVF Input Data Downstream Depth 0.00 ft Length 0.00 ft Number Of Steps 0 GVF Output Data Upstream Depth 0.00 ft Profile Description Profile Headloss 0.00 ft Average End Depth Over Rise 0.00 % 8/14/ :18:24 AM Bentley Systems, Inc. Haestad Methods Solution Bentley Center FlowMaster V8i (SELECTseries 1) [ ] 27 Siemons Company Drive Suite 200 W Watertown, CT USA Page 1 of 2

26 Worksheet for 5yr Penn Plus 5yr Commercial GVF Output Data Normal Depth Over Rise % Downstream Velocity Infinity ft/s Upstream Velocity Infinity ft/s Normal Depth 3.09 ft Critical Depth 2.31 ft Channel Slope % Critical Slope ft/ft 8/14/ :18:24 AM Bentley Systems, Inc. Haestad Methods Solution Bentley Center FlowMaster V8i (SELECTseries 1) [ ] 27 Siemons Company Drive Suite 200 W Watertown, CT USA Page 2 of 2

27 Worksheet for 5yr Penn 100yr Com 5yr SNL Project Description Friction Method Solve For Manning Formula Full Flow Diameter Input Data Roughness Coefficient Channel Slope % Normal Depth 3.99 ft Diameter in Discharge ft³/s Results Diameter in Normal Depth 3.99 ft Flow Area ft² Wetted Perimeter ft Hydraulic Radius 1.00 ft Top Width 0.00 ft Critical Depth 3.13 ft Percent Full % Critical Slope ft/ft Velocity 8.54 ft/s Velocity Head 1.13 ft Specific Energy 5.12 ft Froude Number 0.00 Maximum Discharge ft³/s Discharge Full ft³/s Slope Full ft/ft Flow Type SubCritical GVF Input Data Downstream Depth 0.00 ft Length 0.00 ft Number Of Steps 0 GVF Output Data Upstream Depth 0.00 ft Profile Description Profile Headloss 0.00 ft Average End Depth Over Rise 0.00 % 8/14/ :03:31 AM Bentley Systems, Inc. Haestad Methods Solution Bentley Center FlowMaster V8i (SELECTseries 1) [ ] 27 Siemons Company Drive Suite 200 W Watertown, CT USA Page 1 of 2

28 Worksheet for 5yr Penn 100yr Com 5yr SNL GVF Output Data Normal Depth Over Rise % Downstream Velocity Infinity ft/s Upstream Velocity Infinity ft/s Normal Depth 3.99 ft Critical Depth 3.13 ft Channel Slope % Critical Slope ft/ft 8/14/ :03:31 AM Bentley Systems, Inc. Haestad Methods Solution Bentley Center FlowMaster V8i (SELECTseries 1) [ ] 27 Siemons Company Drive Suite 200 W Watertown, CT USA Page 2 of 2

29 Worksheet for 5yr Penn 5yr Com 5yr SNL Project Description Friction Method Solve For Manning Formula Full Flow Diameter Input Data Roughness Coefficient Channel Slope % Normal Depth 3.75 ft Diameter in Discharge ft³/s Results Diameter in Normal Depth 3.75 ft Flow Area ft² Wetted Perimeter ft Hydraulic Radius 0.94 ft Top Width 0.00 ft Critical Depth 2.92 ft Percent Full % Critical Slope ft/ft Velocity 8.19 ft/s Velocity Head 1.04 ft Specific Energy 4.79 ft Froude Number 0.00 Maximum Discharge ft³/s Discharge Full ft³/s Slope Full ft/ft Flow Type SubCritical GVF Input Data Downstream Depth 0.00 ft Length 0.00 ft Number Of Steps 0 GVF Output Data Upstream Depth 0.00 ft Profile Description Profile Headloss 0.00 ft Average End Depth Over Rise 0.00 % 8/14/ :19:27 AM Bentley Systems, Inc. Haestad Methods Solution Bentley Center FlowMaster V8i (SELECTseries 1) [ ] 27 Siemons Company Drive Suite 200 W Watertown, CT USA Page 1 of 2

30 Worksheet for 5yr Penn 5yr Com 5yr SNL GVF Output Data Normal Depth Over Rise % Downstream Velocity Infinity ft/s Upstream Velocity Infinity ft/s Normal Depth 3.75 ft Critical Depth 2.92 ft Channel Slope % Critical Slope ft/ft 8/14/ :19:27 AM Bentley Systems, Inc. Haestad Methods Solution Bentley Center FlowMaster V8i (SELECTseries 1) [ ] 27 Siemons Company Drive Suite 200 W Watertown, CT USA Page 2 of 2

31 Worksheet for outfall pipe to culvert 100yr Project Description Friction Method Solve For Manning Formula Full Flow Diameter Input Data Roughness Coefficient Channel Slope % Normal Depth 4.13 ft Diameter in Discharge ft³/s Results Diameter in Normal Depth 4.13 ft Flow Area ft² Wetted Perimeter ft Hydraulic Radius 1.03 ft Top Width 0.00 ft Critical Depth 3.16 ft Percent Full % Critical Slope ft/ft Velocity 8.26 ft/s Velocity Head 1.06 ft Specific Energy 5.19 ft Froude Number 0.00 Maximum Discharge ft³/s Discharge Full ft³/s Slope Full ft/ft Flow Type SubCritical GVF Input Data Downstream Depth 0.00 ft Length 0.00 ft Number Of Steps 0 GVF Output Data Upstream Depth 0.00 ft Profile Description Profile Headloss 0.00 ft Average End Depth Over Rise 0.00 % 8/14/ :04:08 AM Bentley Systems, Inc. Haestad Methods Solution Bentley Center FlowMaster V8i (SELECTseries 1) [ ] 27 Siemons Company Drive Suite 200 W Watertown, CT USA Page 1 of 2

32 Worksheet for outfall pipe to culvert 100yr GVF Output Data Normal Depth Over Rise % Downstream Velocity Infinity ft/s Upstream Velocity Infinity ft/s Normal Depth 4.13 ft Critical Depth 3.16 ft Channel Slope % Critical Slope ft/ft 8/14/ :04:08 AM Bentley Systems, Inc. Haestad Methods Solution Bentley Center FlowMaster V8i (SELECTseries 1) [ ] 27 Siemons Company Drive Suite 200 W Watertown, CT USA Page 2 of 2

33 Worksheet for outfall pipe to culvert 5yr Project Description Friction Method Solve For Manning Formula Full Flow Diameter Input Data Roughness Coefficient Channel Slope % Normal Depth 4.01 ft Diameter in Discharge ft³/s Results Diameter in Normal Depth 4.01 ft Flow Area ft² Wetted Perimeter ft Hydraulic Radius 1.00 ft Top Width 0.00 ft Critical Depth 3.06 ft Percent Full % Critical Slope ft/ft Velocity 8.10 ft/s Velocity Head 1.02 ft Specific Energy 5.03 ft Froude Number 0.00 Maximum Discharge ft³/s Discharge Full ft³/s Slope Full ft/ft Flow Type SubCritical GVF Input Data Downstream Depth 0.00 ft Length 0.00 ft Number Of Steps 0 GVF Output Data Upstream Depth 0.00 ft Profile Description Profile Headloss 0.00 ft Average End Depth Over Rise 0.00 % 8/14/ :23:40 AM Bentley Systems, Inc. Haestad Methods Solution Bentley Center FlowMaster V8i (SELECTseries 1) [ ] 27 Siemons Company Drive Suite 200 W Watertown, CT USA Page 1 of 2

34 Worksheet for outfall pipe to culvert 5yr GVF Output Data Normal Depth Over Rise % Downstream Velocity Infinity ft/s Upstream Velocity Infinity ft/s Normal Depth 4.01 ft Critical Depth 3.06 ft Channel Slope % Critical Slope ft/ft 8/14/ :23:40 AM Bentley Systems, Inc. Haestad Methods Solution Bentley Center FlowMaster V8i (SELECTseries 1) [ ] 27 Siemons Company Drive Suite 200 W Watertown, CT USA Page 2 of 2

35 Cross Section for washington sump xsection Project Description Friction Method Solve For Manning Formula Normal Depth Input Data Channel Slope % Normal Depth 1.50 ft Discharge ft³/s Cross Section Image 8/14/ :28:31 PM Bentley Systems, Inc. Haestad Methods Solution Bentley Center FlowMaster V8i (SELECTseries 1) [ ] 27 Siemons Company Drive Suite 200 W Watertown, CT USA Page 1 of 1

36 Cross Section for washington sump xsection minus culvert capcity Project Description Friction Method Solve For Manning Formula Normal Depth Input Data Channel Slope % Normal Depth 1.16 ft Discharge ft³/s Cross Section Image 8/14/ :30:19 PM Bentley Systems, Inc. Haestad Methods Solution Bentley Center FlowMaster V8i (SELECTseries 1) [ ] 27 Siemons Company Drive Suite 200 W Watertown, CT USA Page 1 of 1

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