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Home My WebLink About19 - Design Report - Tschache Apartments - Water, Wastewater ENGINEERING CONSULTING PLANNING DESIGN 204 N. 11th Ave.  BOZEMAN, MT 59715  406-581-3319  www.g-e-i.net 204 N. 11th Ave., Bozeman, MT 59715 Cell: (406) 581-3319 www.g-e-i.net Page 1 of 5 Water and Wastewater Design Report Tschache Apartments – Infrastructure Improvements 2420-2440 Tschache Lane Bozeman, Montana January 2019 Prepared By: Genesis Engineering, Inc. GEI Project #: 1086.011 Prepared For: Black Dirt, LLC 2320 W Main Street Suite 6 Bozeman, MT 59715 204 N. 11th Ave., Bozeman, MT 59715 Cell: (406) 581-3319 www.g-e-i.net Page 2 of 5 H:\1086\011\DOCS\DESIGN\WTR-SWR\WaterWastewaterDR.doc Water and Wastewater Design Report Table of Contents I. Project Background………………………………………………………………………………………………. 3 1. Introduction……………………………………………………………………………………………………………… 3 2. Soil and Groundwater………………………………………………………………………………………………. 3 3. Land Use…………………………………………………………………………………………………………………… 3 4. Design Standards……………………………………………………………………………………………………… 3 II. Sanitary Sewer System……………………………………………………………………………………. 4 1. Projected Flows…………………………………………………………………………………………………….….. 4 2. Collection System……………………………………………………………………………………………….……. 4 3. Service Connections………………………………………………………………………………………….……... 4 III. Water System……………………………………………………………………………………………….….… 5 1. Projected Usage………………………………………………………………………………………………….……. 5 2. Hydraulic Analysis……………………………………………………………………………………………….……. 5 3. Water Distribution System…………………………………………………………………………………….…. 5 4. Service Connections……………………………………………………………………………………………..….. 6 IV. Conclusion……………………………………………………………………………………………………..….. 6 Appendix A—Drawings & WaterCAD List of References City of Bozeman Design Standards and Specifications Policy, 6th Edition, March 2011, and all addenda. Montana Public Works Standard Specifications (MPWSS), 6th Edition City of Bozeman Modifications to the MPWSS, March 2011, and all Addenda Montana Department of Environmental Quality (MDEQ) Design Circulars DEQ-1 and DEQ-2 204 N. 11th Ave., Bozeman, MT 59715 Cell: (406) 581-3319 www.g-e-i.net Page 3 of 5 H:\1086\011\DOCS\DESIGN\WTR-SWR\WaterWastewaterDR.doc I. Project Background I-1. Introduction The Tschache Apartments Siteplan is a proposed 54 unit residential apartment building project on approximately 3 acres located in Section 02, T2S, R5E, PMM in Bozeman, Gallatin County, Montana. The project includes a water and sewer main extensions in Tschache Lane. The property lies west of North 19th Ave, east of 27th Ave and north of W Oak Ave, and south of Tschache Lane. I-2. Soils The NRCS Soil Survey identifies three major soil types on the proposed project site: Blackdog silt loam (50B), Meadowcreek loam (510B), and Lamoose silt loam (537A). Blackdog silt loam and Meadowcreek loam belong to hydrologic soil group C as it is comprised primarily of loams. Lamoose silt loam belonging to hydrologic soil group B/D and is made up of primarily silt loam. All soils on the site have moderately high to high saturated hydraulic conductivity. I-3. Land Use The land is currently undeveloped. Upon development, the Owners anticipate that the site will consist of 54 units of multi-family residential living. I-4. Design Standards All sanitary sewer mains, water mains, service connections, and appurtenances will be designed and constructed in accordance with the Montana Public Works Standard Specifications (MPWSS), 6th Edition; City of Bozeman Design Standards and Specifications Policy (including Addenda 1-4), March 2004; City of Bozeman Modifications to the MPWSS, March 2011 (including Addenda); the Montana Department of Environmental Quality (MDEQ) Design Circulars DEQ-1 and DEQ-2, and any additional addenda thereof. The City of Bozeman will assume operation and maintenance of the wastewater and water systems and appurtenances upon construction and acceptance of the installation. II. Sanitary Sewer System II-1. Proposed Design Flow The proposed site includes 54 multi-family residential units on approximately 3 acres. Average day flows were calculated using the City of Bozeman standard of 2.11 persons per residential unit at 89 gpd per person. The estimated Average Daily Flow from the subdivision is 10,141 gpd. Average Daily Flowrate = (54 units) x (2.11 people/unit) x (89 gpd/person) = 10,141 gpd The City of Bozeman standard 2.11 persons per residential unit was multiplied by 54 units to determine an equivalent population for the subdivision of 114 people, yielding a peaking factor of 4.22. The peaking factor, PF, was calculated by the following formula, where P = population (thousands): PF = 18 + P0.5 4 + P0.5 Using peak hour factor of 4.22 was and adding the City’s infiltration allowance of 150 gallons per acre per day resulted in a combined peak hourly flowrate of 42,742 gpd. 204 N. 11th Ave., Bozeman, MT 59715 Cell: (406) 581-3319 www.g-e-i.net Page 4 of 5 H:\1086\011\DOCS\DESIGN\WTR-SWR\WaterWastewaterDR.doc Peak Hourly Flowrate = ADF x PHF + 150 gpd/acre Peak Hourly Flowrate = 10,141 gpd x 4.22 + 150 gpd x 3.07 = 42742 gpd Using Manning’s Equation and a minimum slope of 0.004 ft/ft for an 8-inch diameter pipe, the full-flow capacity of the pipe is 0.76 cfs or 497,629 gallons per day. The empirically-based peak design flow occupies 4.1% of the proposed pipe. The full flow velocity of the 8-inch diameter SDR-35 main is 2.2 ft/sec, exceeding the minimum of 2.0 ft/sec required. People per square foot on the first floor = (6 units) x (2.11 people/unit) / (8,247 square feet) = .0015 people / sqft II-2. Collection System The wastewater will be collected within the site and then connect into the existing 8-inch sewer main in Tschache Lane where it flows to the east to the 8 inch line flowing north through the Home Depot parking lot where it will connect to the existing 24” sewer main in Baxter Lane. Five (5) 48-inch sanitary sewer manholes are proposed with this project. The maximum distance between manholes is less than 400 feet as per City regulations. The slope of the pipe segments are all greater than or equal to 0.40%, which satisfies City requirements for minimum slope of an 8-inch pipe. II-3. Service Connections Service connections (4-inch) are proposed for each of the three buildings. Connections to the sanitary sewer mains will be designed in accordance with the City’s Design Standards and Specifications Policy. Connections to the sewer main will be made with in-line gasketed wyes. III. Water System III-1. Projected Usage Tschache Apartments consists of 54 multi-family units. Using the City of Bozeman empirical data of 170 gpd/person, Genesis estimated the total average daily demand (ADD) as seen below. Using the City’s max day flow factor of 2.3, results in the maximum daily demand as shown below. Multiplying the average daily flow by the City’s peak hour factor of 3, results in a peak hour demand as shown below. Local landscape watering is included in the empirical data. The average daily demands are exclusive of the suggested fire flow requirement of 2,000 gallons per minute. When modeled, the system design satisfies the fire flow occurring simultaneously with the maximum day demands. Average Daily Flowrate = (54 units) x (2.11 people/unit) x (170 gpd/person) = 19,370 gpd 19,370 gpd /1440 min per day = 13.45 gpm Maximum Daily Flowrate = ADF x 2.3 = 13.45 gpm x 2.3 = 30.94 gpm Peak Hour Flowrate = ADF x 3 = 13.45 gpm x 3 = 40.35 gpm III-2. Hydraulic Analysis The hydraulic modeling program WaterGEMS was used to model domestic and fire protection demands for the proposed site. The model used hydrant flow test results as provided by the City of Bozeman on August 13th, 2018. The hydrant test results are included in the appendix. The results of the model are as follows: 204 N. 11th Ave., Bozeman, MT 59715 Cell: (406) 581-3319 www.g-e-i.net Page 5 of 5 H:\1086\011\DOCS\DESIGN\WTR-SWR\WaterWastewaterDR.doc Available Fire Flow - 2,702 gpm at 34.5 psi at junction H-1. Maximum System Pressure – 82-84 psi throughout most of system. It is noted that the system was modeled at a small scale with only one input pipe versus the loop that exists and therefore the results are likely conservative. The WaterGEMS modeling results are included in the appendix of this report. III-3. Water Distribution System Approximately 500 lineal feet of 8-inch diameter ductile iron pipe (DIP) Class 51 water main will be installed for the proposed project. The new mains will be connected to the existing 8-inch DIP water main in Tschache Lane. All proposed water mains will be designed to meet the 10-foot horizontal and 18-inch vertical separation requirements from all proposed sanitary and storm sewer mains. III-4. Service Connections Future service connections to the water mains will be designed in accordance with the City’s Design Standards and Specifications Policy and sized based on the projected usage for each service line. Service lines less than 4 inches in diameter will be type “K” copper pipe, while those larger than 4 inches will be ductile iron. Water services will meet all applicable design standards and flow requirements. IV. Conclusion The analysis and calculations included in this report demonstrate that the proposed designs for water provision, including fire flow, and wastewater disposal satisfy state and local design requirements. Average Day Analysis (Tschache.wtg) Current Time: 0.000 hoursPressure(psi)Hydraulic Grade(ft)Demand(gpm)Demand CollectionZoneElevation(ft)LabelID84.04,887.990.00<Collection: 1 items><None>4,693.76J-73983.54,887.994.48<Collection: 1 items><None>4,694.93J-84083.34,887.990.00<Collection: 0 items><None>4,695.42J-94283.24,887.994.45<Collection: 1 items><None>4,695.66J-104483.64,887.994.45<Collection: 1 items><None>4,694.82J-114683.74,887.990.00<Collection: 0 items><None>4,694.51J-124879.24,887.990.00<Collection: 0 items><None>4,705.00J-135278.84,887.990.00<Collection: 0 items><None>4,705.80J-145478.54,887.990.00<Collection: 0 items><None>4,706.50J-1760Page 1 of 12/28/2019Bentley WaterGEMS V8i (SELECTseries 3)[08.11.03.19]Bentley Systems, Inc. Haestad Methods Solution Center27 Siemon Company Drive Suite 200 W Watertown, CT 06795 USA +1-203-755-1666Tschache.wtg MAX DAY ANALYSIS (Tschache.wtg) Current Time: 0.000 hoursPressure(psi)Hydraulic Grade(ft)Demand(gpm)Demand CollectionZoneElevation(ft)LabelID84.04,887.970.00<Collection: 1 items><None>4,693.76J-73983.54,887.9710.31<Collection: 1 items><None>4,694.93J-84083.34,887.970.00<Collection: 0 items><None>4,695.42J-94283.24,887.9710.31<Collection: 1 items><None>4,695.66J-104483.64,887.9710.31<Collection: 1 items><None>4,694.82J-114683.74,887.970.00<Collection: 0 items><None>4,694.51J-124879.24,887.970.00<Collection: 0 items><None>4,705.00J-135278.84,887.970.00<Collection: 0 items><None>4,705.80J-145478.54,887.970.00<Collection: 0 items><None>4,706.50J-1760Page 1 of 12/28/2019Bentley WaterGEMS V8i (SELECTseries 3)[08.11.03.19]Bentley Systems, Inc. Haestad Methods Solution Center27 Siemon Company Drive Suite 200 W Watertown, CT 06795 USA +1-203-755-1666Tschache.wtg PEAK HOUR ANALYSIS (Tschache.wtg) Current Time: 0.000 hoursPressure(psi)Hydraulic Grade(ft)Demand(gpm)Demand CollectionZoneElevation(ft)LabelID84.04,887.960.00<Collection: 1 items><None>4,693.76J-73983.54,887.9513.45<Collection: 1 items><None>4,694.93J-84083.34,887.950.00<Collection: 0 items><None>4,695.42J-94283.24,887.9513.45<Collection: 1 items><None>4,695.66J-104483.64,887.9513.45<Collection: 1 items><None>4,694.82J-114683.74,887.950.00<Collection: 0 items><None>4,694.51J-124879.24,887.950.00<Collection: 0 items><None>4,705.00J-135278.84,887.950.00<Collection: 0 items><None>4,705.80J-145478.54,887.950.00<Collection: 0 items><None>4,706.50J-1760Page 1 of 12/28/2019Bentley WaterGEMS V8i (SELECTseries 3)[08.11.03.19]Bentley Systems, Inc. Haestad Methods Solution Center27 Siemon Company Drive Suite 200 W Watertown, CT 06795 USA +1-203-755-1666Tschache.wtg Fire Flow Report (Tschache.wtg) Current Time: 0.000 hoursPressure (Residual Lower Limit)(psi)Flow (Total Available)(gpm)Flow (Total Needed)(gpm)Fire Flow (Available)(gpm)Fire Flow (Needed)(gpm)Satisfies Fire Flow Constraints?Fire Flow IterationsZoneLabel20.02,685.222,000.002,685.222,000.00True5<None>J-720.02,596.632,010.312,586.322,000.00True5<None>J-820.02,571.402,000.002,571.402,000.00True5<None>J-920.02,562.602,010.312,552.292,000.00True5<None>J-1020.02,562.912,010.312,552.602,000.00True5<None>J-1120.02,597.772,000.002,597.772,000.00True5<None>J-1220.02,571.402,000.002,571.402,000.00True5<None>H-120.01,516.282,000.001,516.282,000.00False3<None>J-1320.01,126.892,000.001,126.892,000.00False3<None>J-1420.01,567.862,000.001,567.862,000.00False3<None>J-17Is Fire Flow Run Balanced?Junction w/ Minimum Pressure (System)Pressure (Calculated System Lower Limit)(psi)Pressure (System Lower Limit)(psi)Junction w/ Minimum Pressure (Zone)Pressure (Calculated Zone Lower Limit)(psi)Pressure (Zone Lower Limit)(psi)Pressure (Calculated Residual)(psi)TrueJ-1735.020.0J-1735.035.040.5TrueJ-1335.020.0J-1335.035.039.4TrueJ-1435.020.0J-1435.035.039.1TrueJ-1435.020.0J-1435.035.039.4TrueJ-1735.020.0J-1735.035.040.1TrueJ-1735.020.0J-1735.035.039.7TrueJ-1435.020.0J-1435.035.038.7TrueJ-1462.320.0J-1462.335.020.0TrueJ-1768.920.0J-1768.935.020.0TrueJ-1461.320.0J-1461.335.020.0Page 1 of 12/28/2019Bentley WaterGEMS V8i (SELECTseries 3)[08.11.03.19]Bentley Systems, Inc. Haestad Methods Solution Center27 Siemon Company Drive Suite 200 W Watertown, CT 06795 USA +1-203-755-1666Tschache.wtg Pipe Table (Tschache.wtg) Current Time: 0.000 hoursHas Check Valve?Hazen-Williams CMaterialDiameter(in)Stop NodeStart NodeLength (Scaled)(ft)LabelIDFalse130.0Ductile Iron8.0J-8J-7173.25P-641False130.0Ductile Iron8.0J-9J-866.54P-743False130.0Ductile Iron8.0J-10J-944.43P-845False130.0Ductile Iron8.0J-10J-11161.37P-947False130.0Ductile Iron8.0J-11J-1289.01P-1049False130.0Ductile Iron8.0H-1J-99.93P-1151False130.0Ductile Iron4.0J-13J-884.71P-1253False130.0Ductile Iron4.0J-14J-10169.10P-1355False130.0Ductile Iron4.0J-17J-1176.14P-1661False130.0Ductile Iron8.0J-7PMP-124.93P-1870False130.0Ductile Iron8.0PMP-1R-16.37P-1971False130.0Ductile Iron8.0J-7J-12131.21P-2079Length (User Defined)(ft)Has User Defined Length?Headloss Gradient(ft/ft)Velocity(ft/s)Flow(gpm)Minor Loss Coefficient (Local)0.00False0.0000.1421.360.0000.00False0.0000.057.900.0000.00False0.0000.057.900.0000.00False0.0000.045.560.0000.00False0.0000.1219.010.0000.00False0.0000.000.000.0000.00False0.0000.000.000.0000.00False0.0000.000.000.0000.00False0.0000.000.000.0000.00False0.0000.2640.370.0000.10True0.0000.2640.370.0000.00False0.0000.12-19.010.000Page 1 of 12/28/2019Bentley WaterGEMS V8i (SELECTseries 3)[08.11.03.19]Bentley Systems, Inc. Haestad Methods Solution Center27 Siemon Company Drive Suite 200 W Watertown, CT 06795 USA +1-203-755-1666Tschache.wtg