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HomeMy WebLinkAbout16 - Design Report - Cottonwood Corner Apartments - Water, Sewer WATER AND SEWER DESIGN REPORT COTTONWOOD CORNER APARTMENTS Prepared for: 213 Holdings LLC. P.O. Box 10968, Bozeman, MT 59719 Prepared by: C&H Engineering and Surveying, Inc. 1091 Stoneridge Drive, Bozeman, MT 59718 (406) 587-1115 w } r.!nNt Project Number: 16837 OCTOBER 2016 0 Y INTRODUCTION The Cottonwood Corner Apartment project includes the construction of five (5) buildings with a total of 78 residential units and associated parking and utility infrastructure on Lots IA and 113, Minor Subdivision No. 340B located in the Southwest Quarter of Section 10, Township 2 South, Range 5 East of P.M.M, City of Bozeman, Gallatin County, Montana. This project will require connecting to the existing City of Bozeman water and sanitary sewer systems. WATER SYSTEM LAYOUT Current water mains in the area utilized for the Cottonwood Corner Apartments include a 12- inch ductile iron pipe (DIP) located in West Babcock Street on the north side of the site and a 12- inch ductile iron pipe (DIP) located in Cottonwood Road to the west. An existing 6" water main stub runs east into the site from the main in Cottonwood Road and this stub will be used to loop the water main from West Babcock Street where a 12" by 8" tapping saddle will be installed. The 12"water main in West Babcock Street will be a live tap. A WaterCAD analysis is enclosed at the end of the report analyzing all mains installed with this project. The connections to the existing system were modeled based on hydrant data for the hydrant located at Palisade Drive and Hanley Avenue (Hydrant 41850). This information was provided by the City of Bozeman from a test conducted on 10/1/2015. WATER DISTRIBUTION SYSTEM SIZING West Section Input Data Average Daily Residential Usage = 170 gallons per capita per day Average Population Density = 2.11 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) Design Report-Page 2 of 8 Water Demands (78 dwelling units) Average Day Demand = 78 d.u. x 2.l l persons/d.u. x 170 gpcpd=27,978.6 gpd= 19.43 gpm Maximum Day Demand = 19.43 gpm x 2.3 =44.69 gpm Peak Hour Demand = 19.43 gpm x 3.0 = 58.29 gpm Available Pressure: 8-inch main located at Palisade Drive and Hanley Avenue (Hydrant#1850) Static= 129 psi Pitot= 103 psi Residual = 116 psi HYDRAULIC ANALYSIS Design Report-Page 3 of 8 A water distribution model was created using WaterCAD Version 6.5 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 Average Day, Maximum Day and Peak Hour within the project. The peaking factor for each case is 1, 2.3 and 3.0 respectively. Cottonwood Corner AVG. MAX. PEAK JUNCTION # OF DAY DAY HOUR NODE UNITS GPM GPM GPM APT1 12 2.99 6.88 8.97 APT2 12 2.99 6.88 8.97 APT3 12 2.99 6.88 8.97 APT4 21 5.23 12.03 15.69 APT5 21 5.23 12.03 15.69 Total 78 19.43 44.69 58.29 Static, residual and pitot pressures were obtained from fire hydrant #1850. Measurements obtained by the City of Bozeman Water Department were used in the model and can be found in Appendix A along with all other model input. This flow/pressure information was used to develop relationships between static head and flow at the tie in point. This relationship was used in the model by simulation of a pump at the connection point. 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 pump. The input data and pump curve are included at the end of the report. Design Report-Page 4 of 8 DISTRIBUTION MAIN The 8-inch DIP water main does provide adequate capacity with regards to the Peak Hour Demands. The flows and pressures within the system for the Peak Hour Demands were generated with the WaterCAD program and can be found at the end of the report. 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 domestic service to the proposed apartment buildings. The results of the analysis at peak hourly flow are given at the end of the report. Design Report-Page 5 of 8 SEWER SYSTEM The sewer main at Cottonwood Corner Apartments will connect to an existing 8" PVC sewer stub off of an existing manhole located in West Babcock Street. The main in West Babcock Street, which flows west to the intersection of West Babcock Street and Cottonwood Road, is a 10"PVC SDR35 line. 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. An 8-inch main is used because that is the minimum diameter allowed within the City of Bozeman. Using the city average of 2.11 persons per household the equivalent is calculated. Cottonwood Corner Equivalent Population = (2.11 persons/dwelling unit)(78 units)= 165 persons Harmon Formula: Peaking Factor= (18 +p0.5)/(4 +po.5) where: P =Population in thousands Peaking Factor= (18 + 0.1650-5)/(4 +0.1650.5) Peaking Factor=4.18 Assumed infiltration rate= 150 gallons/acre/day= 150 (3.86 acres) = 579 gal/day The peak flow rate is calculated by multiplying the City's design generation rate of 89 gallons per capita per day by the population, multiplying by the peaking factor, and adding the infiltration rate: Peak Flow Rate = 89 gpcpd (165 persons) (4.17) + 579 gpd= 61,815 gpd =42.9 gpm (0.0956 cfs) Design Report-Page 6 of 8 The capacity of an 8-inch main is checked using Manning's Equation: Qfuil= (1.486/0.013)AR2i3Sv2 For the new 8-inch main: Manning's n = 0.013 for PVC Pipe Minimum Slope = 0.01 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 R2i3 = 0.30105 ft S =0.01 ft/ft S 1/2= 0.1 ft/ft Qfuu= (1.486/0.013)(0.34907)(0.30105)(0.1) = 1.2012 cfs For the existing 12-inch main: Manning's n = 0.013 for PVC Pipe Minimum Slope = 0.003 ft/ft A=area= (3.14/4)d 2= (3.14/4)(12/12)2= 0.785 ft2 P =perimeter=2(3.14)r=2(3.14)(6/12) = 3.14 ft R=hydraulic radius =A/P = 0.34907/2.0944 = 0.25 ft R2i3 = 0.39685ft S =0.003 ft/ft Slit = 0.0547ft/ft Qfuu = (1.486/0.013)(0.785)(0.39685)(0.0547) = 1.9479 cfs Design Report-Page 7 of 8 Based on these calculations the percent of full capacity is calculated for the service area. Q/Qf,,u = 0.0956/1.2012 = 0.1259 or 7.96% Based on these calculations, an 8-inch sewer line is more than adequate to carry the total design flows from this project. The May 2015 Bozeman Wastewater Collection Facilities Plan Update indicates that the sewer mains in the vicinity of the project are operating at less than 50% capacity. The 0.0956 CFS that this project generates should only slightly increase the load on the existing 12-inch main and represents only a 4.9% increase in flows through the existing 12- inch main. Design Report-Page 8 of 8 Scenario Summary Report Scenario: Peak Hour Scenario Summary Active Topology Alternative Base-Active Topology Physical Alternative Base-Physical Demand Alternative Base-Average Daily Initial Settings Alternative Base-Initial Settings Operational Alternative Base-Operational Age Alternative Base-Age Alternative Constituent Alternative Base-Constituent Trace Alternative Base-Trace Alternative Fire Flow Alternative Base-Fire Flow Capital Cost Alternative Base-Capital Cost Energy Cost Alternative Base-Energy Cost User Data Alternative Base-User Data Hydraulic Analysis Summary Analysis Steady State Friction Method-iazen-Williams Formula Accuracy 0.001000 Trials 40 Quality Analysis Summary Analysis Constituent Quality Time Step 0.08 hr Age Tolerance 0.01 hr Constituent Tolerance 0.01 mg/I Trace Tolerance 1.0 % Global Adjustments Demand Operation <None> Roughness Operation <None> Demand 0.00 Roughness 0.00 Created:03/17/15 11:50:33 AM Project Engineer: Mark Chandler g:\...\16387\design reports\16387 water system.wcd C&H Engineering&Surveying,Inc. WaterCAD v6.5[6.5120] 10/31/16 10:45:25 AM ©Haestad Methods, Inc. 37 Brookside Road Waterbury,CT 06708 USA +1-203-755-1666 Page 1 of 1 Scenario: Peak Hour Fire Flow Analysis Fire Flow Report Label Fire Flow Fire Flow Satisfies Needed Available Total Total Residual Iterations Balanced? Fire Flow Fire Flow Fire Flow Flow Pressure Constraints? (gpm) Flow Needed Available (psi) (gpm) (gpm) (gpm) APT1 17 true true 1,500.00 4,852.61 1,508.97 4,861.58 20.00 APT2 17 true true 1,500.00 4,722.13 1,508.97 4,731.10 20.00 APT3 17 true true 1,500.00 4,589.06 1,508.97 4,598.03 20.00 APT4 17 true true 1,500.00 4,590.10 1,515.69 4,605.79 20.00 APT5 17 true true 1,500.00 4,069.74 1,515.69 4,085.43 20.00 COTTONWOOD AND W BABCOCK 16 true true 1,500.00 5,093.46 1,500.00 5,093A6 20.00 COTTONWOOD RD 16 true true 1,500.00 4,962.72 1,500.00 4,962.72 20.00 FIRE 1 18 true true 1,500.00 1,786.96 1,500.00 1,786.96 20.00 FIRE 2 19 true true 1,500.00 1,769.29 1,500.00 1,769.29 20.00 FIRE 3 17 true true 1,500.00 2,236.82 1,500.00 2,236.82 20.00 FIRE 4 16 true true 1,500.00 2,236.95 1,500.00 2,236.95 20.00 FIRE 5 19 true true 1,500.00 1,529.28 1,500.00 1,529.28 20.00 HYD-1 16 true true 1,500.00 3,702.04 1,500.00 3,702.04 20.00 11 16 true true 1,500.00 4,597.49 1,500.00 4,597.49 20.00 J2 18 true true 1,500.00 4,151.91 1,500.00 4,151.91 20.00 REDUCER 17 true true 1,500.00 4,612.40 1,500.00 4,612.40 20.00 W BABCOCK AND LOT 1A 1B 181 true I true 1 1,500.001 5,231.40 11,500.0015,231.401 20.00 Project Engineer:Mark Chandler g:\...\16387\design reports\16387 water system.wcd C&H Engineering&Surveying,Inc. WaterCAD v6.5[6.5120] 10/31/16 11:29:09 AM ©Haestad Methods, Inc. 37 Brookside Road Waterbury,CT 06708 USA +1-203-755-1666 Page 1 of 2 Scenario: Peak Hour Fire Flow Analysis Fire Flow Report Calculated Minimum Zone Calculated Minimum Residual Pressure Minimum Zone Pressure (psi) Zone Junction (psi) Pressure (psi) 20.00 20.00 20.00 FIRE 1 20.00 20.00 20.00 FIRE 2 20.00 20.00 20.00 FIRE 3 20.00 20.00 20.00 FIRE 4 20.00 20.00 20.00 FIRE 5 22.24 20.00 20.00 COTTONV 20.00 20.00 23.24 REDUCEF 20.00 20.00 109.08 FIRE 5 20.00 20.00 108.64 FIRE 5 20.00 20.00 97.83 APT3 20.00 20.00 97.84 APT4 20.00 20.00 108.38 APT5 20.00 20.00 40.20 APT5 20.36 20.00 20.00 APT5 20.00 20.00 20.00 APT5 20.00 20.00 22.82 FIRE 4 22.851 20.001 20.00 APTS Project Engineer:Mark Chandler g:\...\16387\design reports\16387 water system.wcd C&H Engineering&Surveying,Inc. WaterCAD v6.5[6.5120] 10/31/16 11:29:09 AM ©Haestad Methods,Inc. 37 Brookside Road Waterbury,CT 06708 USA +1-203-755-1666 Page 2 of 2 Scenario: Peak Hour Fire Flow Analysis Pipe Report Downstream StructurE Pressure Headloss Hydraulic Grade Pipe Gradient (ft) Headloss (ft/1000ft) (ft) 5,064.69 0.00 0.00 5,064.70 0.00 0.00 5,064.70 0.01 0.05 4,767.44 0.00 0.00 5,064.70 0.00 0.00 5,064.69 0.00 0.02 5,064.69 0.00 0.01 5,064.69 0.00 0.01 5,064.68 0.00 0.02 5,064.69 0.00 0.00 5,064.69 0.00 0.00 5,064.69 0.00 0.00 5,064.69 0.00 0.02 5,064.69 0.01 0.07 5,064.69 0.00 0.00 5,064.69 0.00 0.00 5,064.68 0.00 0.00 5,064.69 0.00 0.00 5,064.6910.001 0.00 Project Engineer:Mark Chandler g:\...\16387\design reports\16387 water system.wcd C&H Engineering&Surveying,Inc. WaterCAD v6.5[6.5120] 10/31/16 11:30:25 AM ©Haestad Methods, Inc. 37 Brookside Road Waterbury,CT 06708 USA +1-203-755-1666 Page 2 of 2 Scenario: Peak Hour Fire Flow Analysis Pipe Report Label Length Diameter Material Hazen- Check Minor Control Discharge Upstream Structure (ft) (in) Williams Valve? Loss Status (gpm) Hydraulic Grade C Coefficient (ft) EXP1 355.00 12.0 Ductile Iron 130.0 false 0.74 Open 23.42 5,064.70 EXP2 295.00 12.0 Ductile Iron 130.0 false 0.75 Open 23.42 5,064.70 P1 130.00 8.0 Ductile Iron 130.0 false 2.02 Open -34.89 5,064.69 P1-a 1.00 99.0 Ductile Iron 130.0 false 0.00 Open 58.32 4,767.44 P1-b 1.00 99.0 Ductile Iron 130.0 false 0.00 Open 58.32 5,064.70 P2 88.00 8.0 Ductile Iron 130.0 false 0.35 Open -25.92 5,064.69 P3 143.00 8.0 Ductile Iron 130.0 false 0.74 Open -16.94 5,064.69 P4 131.00 8.0 Ductile Iron 130.0 false 0.74 Open 15.70 5,064.69 P5 21.00 8.0 Ductile Iron 130.0 false 0.35 Open 15.69 5,064.69 P6 1.00 6.0 Ductile Iron 130.0 false 1.67 Open 0.00 5,064.69 P7 99.00 8.0 Ductile Iron 130.0 false 1.67 Open -1.24 5,064.69 P8 11.00 8.0 Ductile Iron 130.0 false 0.00 Open 7.73 5,064.69 P9 99.00 8.0 Ductile Iron 130.0 false 0.00 Open 23.42 5,064.69 P10 89.00 6.0 Ductile Iron 130.0 false 0.07 Open 23.42 5,064.69 P11 40.00 4.0 Ductile Iron 130.0 false 1.67 Open 0.00 5,064.69 P12 40.00 4.0 Ductile Iron 130.0 false 1.67 Open 0.00 5,064.69 P13 140.00 4.0 Ductile Iron 130.0 false 1.67 Open 0.00 5,064.68 P14 100.00 4.0 Ductile Iron 130.0 false 1.67 Open 0.00 5,064.69 P15 1 100.001 4.01 Ductile Iron 1 130.01 false 1 1.671 Open 0.00 5,064.69 Project Engineer: Mark Chandler g:\...\16387\design reports\16387 water system.wcd C&H Engineering&Surveying,Inc. WaterCAD v6.5[6.5120] 10/31/16 11:30:25 AM ©Haestad Methods, Inc. 37 Brookside Road Waterbury,CT 06708 USA +1-203-755-1666 Page 1 of 2 Scenario: Peak Hour Fire Flow Analysis Junction Report Label Elevation Type Base Flow Pattern Demand Calculated Pressure {ft) (gpm) (Calculated) Hydraulic Grade (psi) (gpm) (ft) APT1 4,767.44 Demand 8.97 Fixed 8.97 5,064.69 128.86 APT2 4,770.53 Demand 8.97 Fixed 8.97 5,064.69 127.52 APT3 4,773.17 Demand 8.97 Fixed 8.97 5,064.69 126.38 APT4 4,773.17 Demand 15.69 Fixed 15.69 5,064.69 126.38 APT5 4,774.00 Demand 15.69 Fixed 15.69 5,064.68 126.02 COTTONWO 4,767.44 Demand 0.00 Fixed 0.00 5,064.70 128.87 COTTONWO 4,773.17 Demand 0.00 Fixed 0.00 5,064.69 126.38 FIRE 1 4,767.44 Demand 0.00 Fixed 0.00 5,064.69 128.86 FIRE 2 4,770.53 Demand 0.00 Fixed 0.00 5,064.69 127.52 FIRE 3 4,773.17 Demand 0.00 Fixed 0.00 5,064.69 126.38 FIRE 4 4,773.17 Demand 0.00 Fixed 0.00 5,064.69 126.38 FIRE 5 4,774.00 Demand 0.00 Fixed 0.00 5,064.68 126.02 HYD-1 4,774.00 Demand 0.00 Fixed 0.00 5,064.69 126.02 11 4,773.17 Demand 0.00 Fixed 0.00 5,064.69 126.38 J2 4,774.00 Demand 0.00 Fixed 0.00 5,064.69 126.02 REDUCER 4,773.17 Demand 0.00 Fixed 0.00 5,064.69 126.38 W BABCOC 4,767.44 Demand 0.00 1 Fixed 10.0015,064.70 128.87 Project Engineer:Mark Chandler g:\...\16387\design reports\16387 water system.wcd C&H Engineering&Surveying,Inc. WaterCAD v6.5[6.5120] 10/31/16 10:46:04 AM 0 Haestad Methods, Inc. 37 Brookside Road Waterbury,CT 06708 USA +1-203-755-1666 Page 1 of 1 Detailed Report for Pump: PMP Scenario Summary Scenario Peak Hour Active Topology Alternative Base-Active Topology Physical Alternative Base-Physical Demand Alternative Base-Average Daily Initial Settings Alternative Base-Initial Settings Operational Alternative Base-Operational Age Alternative Base-Age Alternative Constituent Alternative Base-Constituent Trace Alternative Base-Trace Alternative Fire Flow Alternative Base-Fire Flow Capital Cost Alternative Base-Capital Cost Energy Cost Alternative Base-Energy Cost User Data Alternative Base-User Data Global Adjustments Summary Demand <None> Roughness <None> Geometric Summary X 4,622.62 ft Upstream Pipe P1-a Y 2,653.42 ft Downstream Pipe PI-b Elevation 4,767.44 ft Pump Definition Summary Pump Definition Palisade Dr and S Hanley Ave Initial Status Initial Pump Status On Initial Relative Speed Facto 1.00 Calculated Results Summary Time Control Intake DischargElDischarge Pump RelativeCalculated (hr) Status Pump Pump (gpm) Head Speed Water Grade Grade (ft) Power (ft) (ft) (Hp) 0.00 On 767.44 5,064.70 58.32 197.26 1.00 4.39 Pump Head Curve 300.04 PMP (Relative Speed Factor = 1.00) 250.0 200.0 150.0 r 100.0 50.0 0.0 0.0 1000.0 2000.0 3000.0 4000.0 5000.0 6000.0 Discharge (gpm) Project Engineer:Mark Chandler g:\...\16387\design reports\16387 water system.wcd C&H Engineering&Surveying,Inc. WaterCAD v6.5[6.5120] 10/31/16 10:46:49 AM ©Haestad Methods, Inc. 37 Brookside Road Waterbury,CT 06708 USA +1-203-755-1666 Page 1 of 1 Scenario: Peak Hour COTTONWOOD RD EXP1 COTTONWOOD AND W BABCOCK 40 P10 REDUCER 40 FIRE 5 P9 FIRE 4 P11 APT4 ® EXP2 P8 FIRE 2 FIRE 1 13 P12 FIRE 3 APT3 HYD-1 P14 P7 P15 6 APT5 P5 J2 P4 J1 P3 APT2 P2 APT1 P1 W BABCOCK AND LOT 1A 1 B P1-b PMP P1-a 41 Palisade Dr.and S.Hanley Ave Project Engineer:Mark Chandler g:\...\16387\design reports\16387 water system.wcd C&H Engineering&Surveying,Inc. WaterCAD v6.5[6,5120] 10/31/16 10:52:05 AM ©Haestad Methods, Inc. 37 Brookside Road Waterbury,CT 06708 USA +1-203-755-1666 Page 1 of 1 Pump Curve Calculations: Hydrant 1850 (southeast corner of Palisade Drive and South Hanley Ave. (8-inch main) Pump#1 Static Pressure (Ps) = 129 Pitot Pressure (Pp)= 103 Residual Pressure (Pr) = 116 Qf= 1702 Q=Qf*((Ps-P)/(Ps-Pr))(0.54) Pressure Flow Head 129 0.00 297.69 127 619.42 293.08 122 1218.38 281.54 117 1630.00 270.00 112 1967.31 258.46 107 2261.20 246.92 102 2525.61 235.38 97 2768.29 223.85 92 2994.05 212.31 87 3206.16 200.77 82 3406.93 189.23 77 3598.09 177.69 72 3780.96 166.15 67 3956.60 154.62 62 4125.82 143.08 57 4289.33 131.54 52 4447.70 120.00 47 4601.40 108.46 42 4750.84 96.92 37 4896.39 85.38 32 5038.33 73.85 27 5176.95 62.31 22 5312.48 50.77 17 5445.13 39.23 12 5575.07 27.69 7 5702.49 16.15 2 5827.53 4.62 0 5876.90 0.00