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Home My WebLink About19 - Design Report - Jennifer Place - Water, SewerWATER & SEWER DESIGN REPORT JENNIFER PLACE CONDOMINIUMS PHASE 1-6 SITE PLAN LOT 1, BLOCK 9 LAUREL GLEN SUBDIVISION PHASE 1 Prepared for: Great Western Investment, LLC 15525 Horse Creek Road Bozeman, MT 59715 Prepared by: C&H Engineering and Surveying, Inc. 1091 Stoneridge Drive, Bozeman, MT 59718 (406) 587-1115 Project Number:190065.1 November 2019 INTRODUCTION The Jennifer Place Condominium Master Site Plan proposes to develop Lot 1, Block 9, Laurel Glen Subdivision Phase 1. The proposed development consists of ten 2-unit condominiums with a proposed access road and associated utilities.This project will require connection to existing City of Bozeman water and sanitary sewer systems. WATER SYSTEM LAYOUT The Jennifer Place Condominiums will tap into the existing 8” water mains running along Laurel Parkways (east) and Annie Street (north)as shown on the plans included herein.All new water mains are to be installed in the City standard location and will be located 10’ away from any proposed sewer mains.All water mains will be looped and internal hydrants will be installed no more than 400 feet apart. A WaterCAD analysis is enclosed at the end of the report analyzing the 8-inch water main extension installed with this project. The connection to the existing system was modeled as a pump curve using data obtained from the City of Bozeman Water Department: static, residual and pitot pressures were read at the hydrant located at the intersection of Annie Street/Rosa Way.This data was used to develop the pump curve used at the connection point to model the existing system. The following equation based off of the Hazen Williams method is used to generate the pump curve: Q = Qf x ((Ps -P) / (Ps -Pr))0.54 Where: Q = flow predicted at desired residual pressure, Qf = total flow measured during test, Pr= residual pressure during test, Ps = static pressure and P = residual pressure at the desired flow rate. In the model, the pump is connected to a reservoir which acts as a source of water. The elevation of the reservoir is fixed at the elevation of the pump, which is also equivalent to the elevation of the tie-in point. The reservoir does not create any head on the system; the head is generated entirely by the pumps. The input data and the pump curves are included at the end of the report. The pump curve table includes all calculations and equations used in determining flow characteristics at the connection point. A C-factor of 130 was chosen for ductile iron class 51 pipe. WATER DISTRIBUTION SYSTEM SIZING Residential Units: Average Daily Residential Usage =170 gallons per capita per day Average Population Density =2.17 persons/dwelling unit Minimum Fire Hydrant Flow =1,500 gpm Residual Pressure Required =20 psi for Fire Flow Average Day Demand (Peaking Factor = 1) Maximum Day Demand (Peaking Factor = 2.3) Maximum Hour Demand (Peaking Factor = 3.0) Residential Water Demands (Demand Junction 1) Average Day Demand =20 d.u.x 2.17 persons/d.u. x 170 gpcpd =7,378 gpd =5.1 gpm Maximum Day Demand =5.1 gpm x 2.3 =11.7 gpm Peak Hour Demand =5.1 gpm x 3.0 =15.3 gpm Available Pressure:8-inch class 51 ductile iron main Annie Street and Rosa Way Static = 96 psi (Hydrant #2005) Residual = 88 psi (Hydrant #2005) Pitot (2.5” nozzle) = 80 (Hydrant #1985) Flowing = 1,500 gpm (Hydrant #1985) Water Demands (Demand Junction 1) Average Day Demand = 8 d.u. x 2.17 persons/d.u. x 170 gpcpd = 2,951 gpd = 2.0 gpm Maximum Day Demand = 2.0 gpm x 2.3 = 4.7 gpm Peak Hour Demand = 2.0 gpm x 3.0 = 6.1 gpm Water Demands (Demand Junction 2) Design Report -Page 4 of 8 Average Day Demand = 12 d.u. x 2.17 persons/d.u. x 170 gpcpd = 4,427 gpd = 3.1 gpm Maximum Day Demand = 3.1 gpm x 2.3 = 7.1 gpm Peak Hour Demand = 3.1 gpm x 3.0 = 9.2 gpm HYDRAULIC ANALYSIS A water distribution model was created using WaterCAD Version 10.01.00.72 for demand forecasting and describing domestic and fire protection requirements. In order to model the system, each junction node of the water distribution system was assessed a demand based on its service area. The table shown below quantifies the demands placed at the junction nodes and calculates the demands for the Average Day,Maximum Day and Peak Hour within the development. The peaking factor for each case is 1, 2.3 and 3.0 respectively. Jenny Place Condominiums (Table 1): DEMANDJUNCTIONNODE DWELLINGUNITS (D.U.) POPULATION(RES.) 2.17PEOPLE PERD.U. AVERAGE DAYGPM (170GALLONS PERDAY PERPERSON) MAX.DAYGPM PEAKHOURGPM DJ 1 8 17 2.0 4.7 6.1 DJ 2 12 26 3.1 7.1 9.2 Total 20 43 5.12 11.78 15.37 *See Demand Junction Map for more information on which lots contribute to each DemandJunction. CONCLUSION The proposed 8-inch DIP water mains provide adequate capacity to serve the subdivision under the Peak Hour Demand condition. The flows and pressures within the system for the Peak Hour Demands were generated with the WaterCAD program and can be found in Appendix A. The capacity of the system to meet fire flow requirements was tested by running a steady state fire flow analysis for all junctions at fire hydrant locations. The model shows that all hydrant junctions satisfy fire flow constraints (residual pressure >20 psi,flow rate > 1500 gpm), while providing service to lots at peak hour.The results of the analysis at peak hourly flow are given in Appendix A. Design Report -Page 5 of 8 SANITARY SEWER SYSTEM An 8-inch PVC sanitary sewer line will be installed within the 25-foot public access and utility easement.The proposed main and will flow north and connect with the existing 8-inch main located on Annie Street. DESIGN REQUIREMENTS The flow rates used herein are according to the City of Bozeman Design Standards and Specifications Policy (DSSP)dated March,2004. The peaking factor for the design area is determined by figuring the equivalent population and inserting the population into the Harmon Formula.The population was calculated by applying 2.17 people per dwelling unit and 65 gallons per day (gpd) per person.An 8-inch main is used because that is the minimum diameter allowed within the City of Bozeman. Using the wastewater flow rate by land use designation (Table V-1 in the City of Bozeman Design Standards and Specifications Policy), the average daily flow for the subdivision is calculated. The peaking factor is calculated by using the Harmon Formula. Connection: Equivalent Population =(20 dwelling units*2.17 people/unit) =44 persons Harmon Formula:Peaking Factor = (18 + P0.5)/(4 + P0.5) where:P = Population in thousands Peaking Factor = (18 +0.0440.5)/(4 +0.0440.5) Peaking Factor =4.33 Assumed infiltration rate = 150 gallons/acre/day = 150 (2.04 acres) =306 gal/day The peak flow rate is calculated by multiplying the Average Daily Flow (Qave) by the Peaking Factor and adding the assumed infiltration rate: Design Flow Rate =(44 persons*65 gpd/person) = 2,860 gpd = 0.0044 cfs Design Report -Page 6 of 8 Peak Flow Rate =2,860 gpd (4.33) +306 gpd gpd =12,690 gpd =8.813 gpm =0.0196 cfs The capacity of an 8-inch main is checked using Manning’s Equation: Qfull = (1.486/0.013)AR2/3S1/2 For an 8-inch PVC main: Manning's n = 0.013 for PVC Pipe Minimum Slope = 0.004 ft/ft A =area =(3.14/4)d 2 = (3.14/4)(8/12)2 = 0.34907 ft2 P =perimeter =2(3.14)r = 2(3.14)(4/12) = 2.0944 ft R =hydraulic radius =A/P = 0.34907/2.0944 = 0.16667 ft R2/3 = 0.30105 ft S = 0.004 ft/ft S1/2 = 0.0632 ft/ft Qfull = (1.486/0.013)(0.34907)(0.30105)(0.0632)= 0.7592 cfs Connection: Q/Qfull =0.0196 /0.7592 = 0.4775 or 2.58% Based on these calculations,an 8-inch sewer line has adequate capacity to carry the design flows for this development.Additionally, the Laurel Glen lift station has enough capacity to handle the design flow based on a 2002 Lift Station Design Report done by Allied Engineering, and the 2018 Lift Station Analysis completed by C & H Engineering. Design Report -Page 7 of 8 APPENDIX A WATERCAD MODEL Scenario: Base P-5P-7 Page 1 of 127 Siemon Company Drive Suite 200 WWatertown, CT 06795 USA +1-203-755-166610/30/2019 WaterCAD[10.02.02.06]Bentley Systems, Inc. Haestad Methods SolutionCenter190065 water cad model.wtg Scenario Summary Report Scenario: Base Scenario Summary 1ID BaseLabel Notes Base Active TopologyActive Topology Base PhysicalPhysical Base DemandDemand Base Initial SettingsInitial Settings Base OperationalOperational Base AgeAge Base ConstituentConstituent Base TraceTrace Base Fire FlowFire Flow Base Energy CostEnergy Cost Base TransientTransient Base Pressure Dependent DemandPressure Dependent Demand Base Failure HistoryFailure History Base SCADASCADA Base User Data ExtensionsUser Data Extensions Base Calculation OptionsSteady State/EPS Solver Calculation Options Base Calculation OptionsTransient Solver Calculation Options Hydraulic Summary Steady StateTime Analysis Type TrueUse simple controls during steady state? Hazen-WilliamsFriction Method FalseIs EPS Snapshot? 0.001Accuracy 12:00:00 AMStart Time 40Trials Fire FlowCalculation Type Page 1 of 127 Siemon Company Drive Suite 200 W Watertown, CT 06795 USA +1-203-755-1666 10/30/2019 WaterCAD [10.02.02.06] Bentley Systems, Inc. Haestad Methods Solution Center190065 water cad model.wtg Fire Flow Node FlexTable: Fire Flow Report Junction w/ Minimum Pressure (System) Pressure (Calculated Zone Lower Limit) (psi) Pressure (Zone Lower Limit) (psi) Pressure (Calculated Residual) (psi) Pressure (Residual Lower Limit) (psi) Flow (Total Available) (gpm) Flow (Total Needed) (gpm) Fire Flow (Available) (gpm) Fire Flow (Needed) (gpm) Label (N/A)(N/A)0(N/A)20(N/A)(N/A)(N/A)1,500J-5 (N/A)(N/A)0(N/A)20(N/A)(N/A)(N/A)1,500DJ 1 (N/A)(N/A)0(N/A)20(N/A)(N/A)(N/A)1,500DJ 2 DJ 134020202,7871,5002,7871,500Hyd. 1 Page 1 of 127 Siemon Company Drive Suite 200 W Watertown, CT 06795 USA +1-203-755-1666 10/30/2019 WaterCAD [10.02.02.06]Bentley Systems, Inc. Haestad Methods Solution Center190065 water cad model.wtg FlexTable: Pipe Table Headloss Gradient (ft/ft) Hydraulic Grade (Stop) (ft) Hydraulic Grade (Start) (ft) Velocity (ft/s) Flow (gpm) Minor Loss Coefficie nt (Unified) Hazen- Williams C MaterialDiameter (in) Length (User Defined) (ft) Label 0.000269.70269.700.10152.020130.0Ductile Iron8.0208P-3 0.000269.70269.700.0692.060130.0Ductile Iron8.0308P-4 0.00048.0048.000.00150.000150.0PVC999.01P-5 0.000269.70269.700.10150.000150.0PVC8.0500P-6 0.000269.70269.700.0001.280130.0Ductile Iron6.027P-7 Page 1 of 127 Siemon Company Drive Suite 200 W Watertown, CT 06795 USA +1-203-755-1666 10/30/2019 WaterCAD [10.02.02.06]Bentley Systems, Inc. Haestad Methods Solution Center190065 water cad model.wtg FlexTable: Junction Table Pressure (psi) Hydraulic Grade (ft) Demand (gpm) Demand CollectionElevation (ft) LabelID 96269.700<Collection: 0 items>48.00J-539 96269.706<Collection: 1 items>48.50DJ 140 97269.709<Collection: 1 items>44.50DJ 242 96269.700<Collection: 0 items>48.50Hyd. 148 Page 1 of 127 Siemon Company Drive Suite 200 W Watertown, CT 06795 USA +1-203-755-1666 10/30/2019 WaterCAD [10.02.02.06]Bentley Systems, Inc. Haestad Methods Solution Center190065 water cad model.wtg Pump Definition Detailed Report: Hydrant 1 (Annie St. X Rosa Way) Element Details 91ID Notes Hydrant 1 (Annie St. X Rosa Way) Label Pump Curve Head(ft)Flow(gpm) 221.540 208.001,284 196.001,781 185.002,181 173.002,526 162.002,835 150.003,117 138.003,379 127.003,625 115.003,857 104.004,079 92.004,290 81.004,493 69.004,688 58.004,876 46.005,059 35.005,236 23.005,408 11.545,576 0.005,739 Pump Efficiency Type BestEfficiencyPointPump Efficiency Type %100.0Motor Efficiency %100.0BEP Efficiency FalseIs Variable Speed Drive? gpm0BEP Flow Transient (Physical) lb·ft²0.000Inertia (Pump and Motor)SI=25, US=1280Specific Speed rpm0Speed (Full)TrueReverse Spin Allowed? Page 1 of 227 Siemon Company Drive Suite 200 W Watertown, CT 06795 USA +1-203-755-1666 10/30/2019 WaterCAD [10.02.02.06] Bentley Systems, Inc. Haestad Methods Solution Center190065 water cad model.wtg Pump Definition Detailed Report: Hydrant 1 (Annie St. X Rosa Way) Page 2 of 227 Siemon Company Drive Suite 200 W Watertown, CT 06795 USA +1-203-755-1666 10/30/2019 WaterCAD [10.02.02.06] Bentley Systems, Inc. Haestad Methods Solution Center190065 water cad model.wtg Design Report -Page 8 of 8 APPENDIX B DEMAND JUNCTION MAP