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HomeMy WebLinkAbout20 - Design Report - Flanders Mill Apartments - Water, Sewer WATER & SEWER DESIGN REPORT FOR: FLANDERS MILL APARTMENTS INFRASTRUCTURE IMPROVEMENTS BOZEMAN, MT Prepared By: MADISON ENGINEERING Madison Engineering 895 Technology Drive, Suite 203 Bozeman, MT 59718 (406) 586-0262 JUNE 2020 SEWER MAIN DESIGN REPORT FOR: FLANDERS MILL APARTMENTS INFRASTRUCTURE IMPROVEI\IENTS BOZEMAN, MT BUnevi uj Cr- S ONA�-����r Q1 Madison Engineering 895 Technology Blvd Ste 203 Bozeman, MT 59718 (406) 586-0262 JtiNE 2020 FLANDERS MILL APARTMENTS INFRASTRUCTURE IMPROVEMENTS SEWER SYSTEM DESIGN REPORT A. General Project Description This report will give an overview of the proposed wastewater collection system for the development of the Multi Phase Flanders Mill Apartments on Lot 1, block 25 of Flanders Mill Subdivision Phase 7, located south of Harvest Parkway and west of Windrow Drive in Bozeman, MT. The zoning for the 9.14-acre parcel is listed as R-4, Residential High Density District. The proposed phased development consists of the 25 buildings with a total of 200 units at full build out. The improvements for development are anticipated to be constructed during the summer of 2020. Included in this report is a description of the proposed wastewater collection system and design parameters. Once the wastewater system is constructed and approved, the system will become a part of the City of Bozeman (C.O.B.) system. The following references were used in the wastewater facilities design and capacity analysis a. COB Design Standards and Specifications Policy, 2017. Addendum #6 b. COB Modification to Montana Public Works Standard Specifications (MPWSS) c. City adopted MPWSS and adopted Addenda d. COB Wastewater Facility Plan, 2017 e. WQB Circular No. 2 f. City of Bozeman Zoning Map The procedures and parameters outlined in the COB Design Standards and Specifications Guide were used in the design of the sewer infrastructure for the proposed development. B. Capacity Analysis The proposed wastewater collection system consists of 862 linear feet of new 8" sewer main and will provide service to the multi-unit residential development. The effluent generated from the proposed buildings will be collected by the wastewater collection system and ultimately flow North to the existing COB sewer collection system located at the intersection of Harvest Parkway and Ryan Sun Way. The wastewater demands from the proposed residential development were estimated based on a flow per capita basis, which provided a more conservative flow than a per zoned acre basis. (COB Table V-1 specifies an average daily flow rate of 1,950 gal/ac-day for R-4 zoning, resulting in 17,823 gpd= 9.14 ac x 1,950 gal/ac-day at full build out. The proposed sewer mains have been sized to flow at no more than 75-percent of full capacity at peak hour conditions of full build out, and a Manning coefficient of 0.013 was used for PVC pipe. Flanders Mill Apartments Infrastructure Improvements Wastewater Design Report Page 1 of 3 8-inch PVC Pipe Capacity Project Description Friction Method Manning Formula Solve For Discharge Input Data Roughness Coefficient 0.013 Channel Slope 0.40000 % Normal Depth 5.58 in Diameter 8.00 in Results Discharge 0.64 fe/s Flow Area 0.26 ft3 Wetted Perimeter 1.32 ft Hydraulic Radius 2.37 in Top Width 0.61 ft Critical Depth 0.38 ft Percent Full 69.8 % (93%full flow capacity x 75%flow depth) Critical Slope 0.00748 ft/ft Velocity 2.45 ft/s Velocity Head 0.09 11 Specific Energy 0.56 fl Froude Number 0.66 Maximum Discharge 0.82 ft'/s Discharge Full 0.76 ft'/s Slope Full 0.00278 ft/ft Flow Type SubCrltIc91 GVF Input Data Downstream Depth 0.00 in Length 0.00 ft Number Of Steps 0 GVF Output Data Upstream Depth 0.00 In Profile Description Profile Headloss 0.00 ft Average End Depth Over Rise 0.00 % Normal Depth Over Rise 69.75 % Downstream Velocity Infinity ft/s Bentley Systems,Inc. Haestad Methods SoIRbnlIW-MawMastcr V61(SELECTserles 11 [08.11.01.031 411112016 9:20:06 AM 27 Slemons Company Drive Suite 200 W Watertown,CT 09795 USA *1.203-766.1666 Page 1 of 2 6Mp•)!q!4x3 poce8 1om*S\3!q!4x3\6Mp\IIIPI eJepuold 9ZL—LL\LLOZ\dtl3d\:5 rc (� N LA z i N I z r? r \mod+\ I: w LJ 1 I f co Of w ui Ch I; °_ w cr I b w cn 1--1 LLJ I � 0 _Z �' r I I 1 w UL I � a ,� I O L 1 0-1 WS- I � —sa WATER MAIN DESIGN REPORT FOR: FLANDERS MILL APARTMENTS INFRASTRUCTURE IMPROVEMENTS BOZEMAN, MT �•``o1.11 fi'l�q l. ~g r��jllS G. + i oil Ut � / V Madison Engineering 895 Technology Blvd Ste 203 Bozeman, MT 59718 (406) 586-0262 JUNE 2020 FLANDERS MILL APARTMENTS INFRASTRUCTURE IMPROVEMENTS WATER SYSTEM DESIGN REPORT A. General This design report will give an overview of the proposed water main extension for the development of Flanders Mill Apartments Infrastructure Improvements. The proposed improvements are anticipated to be constructed during the summer of 2020. Once the water main is constructed and approved, the main will become a part of the City of Bozeman system. The following references were used in the preparation of this report: a. COB Design Standards and Specifications Policy, 2017. Addendum#6 b. COB Modifications to Montana Public Works Standard Specifications (MPWSS). c. WQB Circular No. 1 d. City of Bozeman Zoning Map e. City of Bozeman Water Facility Plan f. 2015 International Fire Code Existing System The proposed water main extension will be served by the existing City of Bozeman water distribution system, which will be looped. The two connection locations are at the existing 8" stub at Harvest Parkway and the existing 8" stub in Windrow Drive. Both existing stubs align with the proposed driveway approaches. The following information was obtained from the City of Bozeman: Hydrant ID#: 2960 Maximum Day Demand Minimum Pressure: 100.02 psi Maximum Day Demand Average Pressure: 102.64 psi Maximum Day Demand Maximum Pressure: 104.11 psi Maximum Day Demand Available Fire Flow at 20 psi: 7796 gpm Hydrant ID#: 2963 Maximum Day Demand Minimum Pressure: 95.14 psi Maximum Day Demand Average Pressure: 97.76 psi Maximum Day Demand Maximum Pressure: 99.21 psi Maximum Day Demand Available Fire Flow at 20 psi: 10,279 gpm The two hydrants listed above were used to model the existing connections to the City system. A three-point pump curve was used to model the existing system. The first point uses the static pressure of the system when the flow is equal to zero. The second point uses the maximum day demand available fire flow at 20 psi (given above). The third point was determined by selecting an arbitrary pressure (55 psi) between the static pressure and the minimum pressure of 20 psi. An example calculation for Hydrant ID #2960 is given below: Flanders Mill Apartments Infrastructure Improvements Water Design Report Pagel of 4 Q,= Qt[(Ps—Pm)/(Ps—Pr)]0.54 Qr= 7,796 [(102.64— 55)/(102.64—20)]0.54 Qr = 5,790 gpm at 55 psi Qt= Maximum Day Demand Available Fire Flow @ 20 psi Qr= Fire Flow at Desired Fire Flow Residual Pressure Ps= Static Pressure Pm = Desired Residual Pressure = 55 psi Pr= Minimum Residual Pressure =20 psi B. Proposed Water System The proposed water main extension for the Flanders Mill Apartments consists of approximately 1,257 linear feet of 8" ductile iron pipe that will connect to the existing water stubs, which were installed with the subdivision. The layout of the proposed water main meets the COB design criteria and will be located within a 30' foot wide public utility easements and separated from the proposed sanitary sewer main by a minimum of 10 feet horizontally. Fire hydrants will be installed per COB design criteria and will not exceed the recommended distance. C. Capacity Analysis The Flanders Mill Apartments water main extension is proposed for the development of the 25 — buildings. The proposed multi-phase project consists of comprised of a total of 200-units (12 - 12 Plexes, 3 —6 plexes, 9—4 Plexes & 1 —Club house with 2 units), which sits on a 9.14 acre R- 4 (Residential High Density District) zoned land. An estimation of the water flow rate was based on the City of Bozeman's design standards and specification policy, which suggests using an average daily flow rate of 2.11 people per dwelling unit and 170-gallons per capita per day. Applied to the units in each phase the required water flow rate is calculated: Phase I ( residents gallons 78 units * 2.11 * 170 day) = 27,979 gpd unit capita Phase II residents gallons (20 units * 2.11 * 170 day) = 7,174 gpd unit capita Phase III ( residents gallons 102 units * 2.11 * 170 day) = 36,587 gpd unit capita Flanders Mill Apartments Infrastructure Improvements Water Design Report Page 2 of 4 Full Build Out ( residents gallons 200 units * 2.11 unit * 170 capita day) = 71,740 gpd ca P Based on these parameters, the phased development will have an estimated water usage of 71,740 gpd (49.8 gpm) at full build out. In addition to the average daily demand, the water main extension must account for peak periods of daily use. Peaking factors are applied to the demand and account for these peak periods in daily use. The peaking factors used are maximum daily use and peak hour and are obtained from the City of Bozeman Design Standards. Table 1 shows the peaking factors and the resultant flows from those factors when applied to the average daily demand. TABLE 1 PEAKING FACTORS Flow Designation Peaking Factor Flow (gpm) Average Day Demand 1 49.8 Maximum Day Demand 2.3 114.5 Maximum Hour Demand 3 149.4 Four types of buildings will be constructed and will consist of 12 plexes, 6 plexes, 4 plexes and a club house (2-2 bedrooms units) for a total of 25 individual buildings. The square footage for each type of building are as follows: 12 Plex= 13,119sf, 6 Plex= 6,600 sf, 4 Plex = 4,423 sf, 4 Plex = 3,906 sf and the club house = 6,366 s£ The units are expected to be type V-B construction with fire sprinklers. A Type V-B 13,119 sf building requires 1,500 gpm for a 2-hour flow duration per the 2015 International Fire Code, Table B 105.1(2). Results Based on the analysis outlined above, the required minimum fire flow is 1,500 gpm and the maximum hour demand is 149.4 gpm. The maximum hour demand was distributed throughout each water service within the subdivision. The attached WaterCAD analysis was designed to incorporate the maximum hour demand throughout the system.A fire flow analysis was performed at each node throughout the system (including the base max. hour demand) where a building has a potential fire flow demand. The flow analysis shows that an 8-inch DI pipe can provide the development with the required flow of 1,500 gpm in addition to the max. hour demand and remain above the minimum pressure of 20 psi. See attached flow analysis for calculations. D. Conclusion Based on this analysis, the proposed 8-inch ductile iron water main serving the Flanders Mill Apartments residential development extension provides adequate service to meet the 200-unit peak Flanders Mill Apartments Infrastructure Improvements Water Design Report Page 3 of 4 Scenario: Automated Fire Flow Analysis Harvest Parkway P-72 P�_1 PM--P�--1 J_38 J45 R' o p o J-84 J4 J-99 rN' J-83 J•36 J•3 J 35 P",c, J 100 94 A� J 2 P 3 'o J-44 a7 J-26 Q h n J_ J-1 o J-6 J86 -25 QS° J-28 a Color Coding Legend J-72 J-90 J_70 Pipe:Diameter(in) v:v%�O J-14 J-27 P-41 P-31 J-51 J-71 J 3 J- P� <= 15 J-61 n J-40 P- 0 J-41 P- 5 p-32 J-49 <= 20 i y_ * J48 <. 60 J-68 &— -69' a 8.0 � a 0 J-62 v � Other d J_7 v P_g J-8 J-85 n d J-74 4i3 J_55 P-SO J-54 J-73 J-16 J-15 ' i9 � N .SJ P-24 � '8 J-9 P-5 J-10 J'88 JP0110 -65 J_5191 J-59 .64 v A, P.`.A p.71 'o J-11 J-89 v J-79 P 7 J-66 J-67 J-19 p 6 U7 J-12 J-52 J-53 78 J-77 P 9 ' J•22 P 55 9.2 J-21 P-14 o -20 a J-91 v u, (6 J-56 J-67 J_33 - p.56 J-29 J 97 J-96 p.29 J-95 P-52 J-30 J-98 J'92 v r00„ P_16 J-34 9 J-17 P-11 °' J-76 v J-75 J-18 5 J•82 J81 P J24 J93 P73 _oR2 y J�2 J•37 m 4 Bentley Systems,Inc. Haestad Methods Solution Watei-CAD CONNECT Edition Update 2 Flanders Mill WaterCad.l.wtg Center [10.02.00.43] 6/19/2020 27 Siemon Company Drive Suite 200 W Page 1 of 1 Watertown,CT 06795 USA +1-203-755-1666 6MP'1!9!4x3:Podpa 1oloM\719!4x3\6MP\IIIW BJDP-ld 8ZL-LL\LIOZ\avoy\:o m N N H N j 3 COo *N�i 0 a � o QZQ r- —�— - o o a r' lot, \ g 1 ' Q LLI \` O Eft— Of w \ L z >- \\\ —Ws I ,� 00 na I�ln I h � � w U Q _. —_- ! r r CL 0.4 a O W I t�V ' cn cr �-, H 4 � TZ - 1 �! � � I j� of o 'Lr}{t t.�l ij i : 55 I - r7 a_jI - w I I- - :� 0 1 ns a O W w Page 1 of 1 Scenario: Automated Fire Flow Analysis Current Time Step: 0.000 h Fire Flow Node FlexTable: Fire Flow Report Fire Flow Fire Flow Flow(Total Flow(Total Pressure Pressure Pressure Junction w/ Label (Needed) (Available) Needed) Available) (Calculated (Zone (Calculated Minimum (gpm) (gpm) (gpm) (gpm) Residual) Lower Zone Lower Pressure (psi) Limit)(psi) Limit)(psi) (Zone) J-13 1,500 3,000 1,500 3,000 79 0 95 J-71 J-15 1,500 3,000 1,500 3,000 73 0 90 J-73 J-21 1,500 3,000 1,500 3,000 72 0 89 J-77 J-23 1,500 3,000 1,500 3,000 72 0 89 J-81 J-25 1,500 3,000 1,500 3,000 79 0 97 J-71 J-34 1,500 3,000 1,500 3,000 67 0 89 J-98 J-35 1,500 3,000 1,506 3,006 65 0 98 J-17 J-40 1,500 3,000 1,500 3,000 90 0 93 J-41 J-42 1,500 3,000 1,500 3,000 87 0 91 J-81 J-63 1,500 3,000 1,500 3,000 79 0 91 J-73 J-65 1,500 3,000 1,500 3,000 78 0 90 J-10 J-67 1,500 3,000 1,500 3,000 77 0 90 J-19 J-75 1,500 3,000 1,500 3,000 71 0 89 J-17 J-96 1.500 1 3,000 1 1,506 1 3.006 68 0 1 89 1 J-98 G:WCAD\2017\17-128 Flanders Mill\dwg\Civil\WaterCad\Flanders Mill WaterCad,1.wtg file:///C:/Users/Teeh7/AppData/Local/Temp/Bentley/WaterCAD/j 1 cwjpuz.xml 6/18/2020