Memorandum. Andy Brotzler, PE WSB & Associates, Inc. Greg Johnson, PE WSB & Associates, Inc. Ray Theiler, EIT WSB & Associates, Inc.

Transcription

1 477 Temperance Street St. Paul, MN (651) Memorandum To: From: Andy Brotzler, PE WSB & Associates, Inc. Greg Johnson, PE WSB & Associates, Inc. Ray Theiler, EIT WSB & Associates, Inc. Date: June 6, 2017 Re: UMore Utilities Evaluation City of Rosemount, MN WSB Project No Introduction The City of Rosemount has received a boundary survey, produced by Hakanson Anderson & Associates (HAA), for the University of Minnesota pertaining to the sale of acres within UMore Park. The survey represents that area considered to be Phase 1 of the UMore site development, which is intended to be residential. The site is south of and adjacent to CSAH 42; west of the future extension of Akron Avenue. WSB & Associates had prepared a Technical Report in 2014 pertaining to utility extensions within the UMore development (See Appendix 1 of this memo), which preliminarily identified serviceability within five areas of the UMore site. Submittal of a boundary survey for the acre sale, prompted the City to revisit the roadway and utility needs associated with both Phase 1 and Phase 2 of the development, including water storage and production capacity as Phase 2 nears development. WSB evaluated and updated the 2014 cost estimates of the water and sanitary utilities to serve the updated UMore Area 1 site configuration provided by HAA on May 25, 2017 (see Appendix 1). The City s 2014 UMore Development Utilities Evaluation, UMore Storage and Fire Flows Memorandum, and 2030 Water and Sanitary Sewer System Plans were also reviewed to determine if the updated site configuration for the Area 1 site would change the previous recommendations for the water and sanitary infrastructure improvements. The cost estimates are also attached as Appendix 2. The 2014 and 2017 costs are summarized as follows: Year of Est Water $463,320 $804,800 Sanitary $365,220 $399,370 Total $828,540 $1,204,180 Building a legacy your legacy. Equal Opportunity Employer wsbeng.com K:\ \Admin\Docs\Phase 1 Residential\Memo - UMore Utility Study Update.docx

2 Mr. Brotzler June 6, 2017 Page 2 The assumptions made in evaluating the utilities are as follows: Gross area of updated configuration is equal to acres. Net developed area and land use for each UMore development are consistent with UMore AUAR assuming 20% of gross area used for local right-of-way, neighborhood parks, and municipal uses (see Appendix 3). Net development area = acres Residential population densities consistent with the UMore Park AUAR. Water demand per residential population of 109 gallons per capita per day (gpcd) consistent with 2015 Rosemount UMore Water Storage and Fire Flows Memorandum. Average day demand to maximum day demand peaking factor consistent with 2015 Rosemount UMore Water Storage and Fire Flows Memorandum of Water demand per employee based on MCES Sewer Availability Charge (SAC) criteria for commercial properties assumed to be 1 SAC unit (274 gal/day) for 14 employees. Population projections were updated based on MCES 2040 Master Water Supply Plan Minimum of 7.5-feet cover for trunk sanitary trunk mains Additional connection to MCES Empire interceptor required to service low lying areas within updated Area site configuration (see Figure 2) Akron Avenue Extension The future extension of Akron Avenue is proposed to be constructed from CSAH 42 approximately 4500 south. The roadway section is proposed to be similar to the city collector roadways, with either a two-lane or three-lane design with sidewalk and/or trail. The cost estimate for the extension of Akron Avenue is $2,700,000. The cost estimate is attached in Appendix 4. There may potentially be cost participation from Dakota County since Akron Avenue is a county road. Further discussions will be needed with Dakota County. Utilities Recommendations The following are assumptions and recommendations for the water and sanitary sewer improvements to accommodate the UMore updated Area 1 site configuration and Area 2: Water: Sanitary: o Average day water demand = 582,000 gallons/per/day o Maximum day peak factor = 2.76 o Fire flow = 3,500 gpm for 3 hours (630,000 gallons) o Connection to existing system via extending trunk watermains into the development consistent with trunk water system plan. o Expansion of originally proposed 12-inch trunk main required to service updated Area 1 site configuration (see Figure 1) o Additional water storage will be needed by 2020, planning should begin in 2018 (see Appendix 5) o Additional production capacity will be needed by 2026, planning should begin in 2024 (see Appendix 5) o Wastewater average day flow generation from updated Area 1 site = 516,000 gallons/per/day o Peak hourly flow = 3.5 times average flow o Overall minimum sanitary sewer cover of 7.5-feet o The updated Area 1 site configuration could be served by extending two trunk sewers south from CSAH 42. The first connection will be required by extending a 24-inch trunk K:\ \Admin\Docs\Phase 1 Residential\Memo - UMore Utility Study Update.docx

3 Mr. Brotzler June 6, 2017 Page 3 o sewer south along Akron Avenue (see Figure 2). The second connection will be required by extending an 8-inch trunk sewer west of Akron Avenue (see Figure 2). No lift stations required WSB appreciates this opportunity to be of service. Please contact me at with and questions or comments. Sincerely, WSB & Associates, Inc. Greg Johnson, PE Water/Wastewater Group Manager K:\ \Admin\Docs\Phase 1 Residential\Memo - UMore Utility Study Update.docx

4 Figures

5 Future Trunk Watermain 12" 8" Existing Watermain 18" 16" 12" 8" 6" Update UMore Area 1 Previous UMore Areas 12-inch Trunk Main Extension Document Path: K:\ \GIS\Maps\Figure1_Area1_water.mxd Date Saved: 6/6/ :31:33 PM Figure 1 - Water Service to UMore Updated Area UMore Utilities Evaluation City of Rosemount 0 1,000 Feet 1 inch = 1,000 feet

6 " " Future Trunk Sewer 24" 8" Existing Gravity Main UMore Area1 Serviceable Area Updated UMore Area 1 " " " " " " " " " " " " " Assumed minimum finished grade elevation of 913-ft to be serviced by 8-inch trunk main Connection to existing MCES Empire Interceptor with 8-inch trunk main Assumed minimum finished grade elevation of 923-ft to be serviced by 24-inch trunk main 8" Gravity 0.4% to serve Area 1 subsewershed " " " " " Connection to existing MCES Empire Interceptor with 24-inch trunk main " " " 24" Gravity 0.08% to serve updated Area 1 site configuration Document Path: K:\ \GIS\Maps\Figure 2_UMore_Area1_Sewershed_Subsewershed_JC.mxd Date Saved: 6/6/2017 1:40:52 PM Figure 2 - Sanitary Service to UMore Updated Area UMore Utilities Evaluation City of Rosemount 0 1,000 Feet 1 inch = 1,000 feet

7 Appendix 1 Updated UMore Area 1 Site Configuration

8 N

9 Appendix 2 Engineer s Opinion of Probable Cost For Update UMore Area 1 Configuration

10 UMore Development Utilities Evaluation City of Rosemount, MN Area 1 Water and Sanitary Sewer Service Engineer's Opinion of Probable Cost Item No. Description Unit Estimated Total Quantity Estimated Unit Price Estimated Total Cost Water Infrastructure " WATER MAIN w/ VALVES, FITTINGS, ETC. (FUNDING PER DEVELOPER OR ASSESSED) LIN FT $0.00 $ " WATER MAIN w/ VALVES, FITTINGS, ETC. LIN FT $70.00 $562, Sanitary Infrastructure CONNECT TO EXISTING EMPIRE INTERCEPTOR LUMP SUM 2.00 $7, $15, " PVC SEWER LIN FT $0.00 $ " PVC SEWER LIN FT $ $228, SANITARY SEWER INSPECTION (TELEVISING) LIN FT $1.20 $2, CONST 48" DIA SAN SEWER MANHOLE EACH 8.00 $3, $29, CASTING ASSEMBLY EACH 8.00 $ $4, SUB TOTAL Cont. 10% SUB TOTAL Engr/Legal 30% TOTAL $842, $84, $926, $277, $1,204, Costs are for budgeting purposes only, and are subject to change as projects are studied, designed, and constructed. 2. Costs are estimated based on 2016 construction costs. 3. Land acquisition costs are not included. 4. All lift stations standard submersible type, no standby generator K:\ \Water - Wastewater\Data\Phase I Residential Cost Estimates_

11 Appendix 3 UMore Development Area Land Use Data

12 Land Use UMore Development Utilities Evaluation City of Rosemount, MN Appendix 3 - Gross Development Area Land Use Data Updated Area 1 Area 2 Gross Gross Acreage Acreage Area 5 Gross Acreage Low Density Residential 77.5 Low Med Density Residential Medium Density Residential High Density Residential Neighborhood Center Low Med Density Residential 18.2 Medium Density Residential 60.3 High Density Residential 30.3 Retail/Commercial/Office 12.1 Village Center Medium Density Residential 21.3 High Density Residential 24.4 Retail/Commercial/Office 15.2 Community Center Medium Density Residential High Density Residential Retail/Commercial/Office Regional Center Medium Density Residential 4.5 High Density Residential 4.5 Retail/Commercial/Office 81.3 Office/Business Park Light Industrial Open Space 19.5 Open Water ROW (Collectors/Arterials) Local Streets/Neighborhood Parks Total

13 Land Use UMore Development Utilities Evaluation City of Rosemount, MN Appendix 3 - Net Development Area Land Use Data Updated Area 1 Area 2 Net Net Acreage Acreage Area 5 Net Acreage Low Density Residential 62.0 Low Med Density Residential Medium Density Residential High Density Residential Neighborhood Center Low Med Density Residential 14.6 Medium Density Residential 48.2 High Density Residential 24.2 Retail/Commercial/Office 9.6 Village Center Medium Density Residential 17.0 High Density Residential 19.5 Retail/Commercial/Office 12.2 Community Center Medium Density Residential High Density Residential Retail/Commercial/Office Regional Center Medium Density Residential 3.6 High Density Residential 3.6 Retail/Commercial/Office 65.0 Office/Business Park Light Industrial Open Space 15.6 Open Water ROW (Collectors/Arterials) Local Streets/Neighborhood Parks Total

14 UMore Development Utilities Evaluation City of Rosemount, MN Appendix 3 - Residential Population and Commerical Employee Density Assumptions Land Use Per/Unit (Per) Units/Acre (DU/AC) Floor Area Ratio (FAR) Structure Finished Area per Acre (SF/AC) Employee per Finished Area (Per) Low Density Residential Low Med Density Residential Medium Density Residential High Density Residential Employee/Acre (Per/AC) Neighborhood Center Low Med Density Residential Medium Density Residential High Density Residential Retail/Commercial/Office (0.35 FAR) Village Center Medium Density Residential High Density Residential Retail/Commercial/Office (0.5 FAR) Community Center Medium Density Residential High Density Residential Retail/Commercial/Office (0.25 FAR) Regional Center Medium Density Residential High Density Residential Retail/Commercial/Office (0.25 FAR) Office/Business Park (0.3 FAR) Light Industrial (0.4 FAR) Open Space Open Water ROW (Collectors/Arterials) Local Streets/Neighborhood Parks

15 Appendix 4 Akron Avenue Cost Estimates

16 Opinion of Probable Cost WSB Project: Akron Avenue South of CSAH 42 (Umore Phase 1 Residential) Project Location: City of Rosemount City Project No.: WSB Project No: Cost / Foot 10% Contingency 25% Indirect Design By: MLH Checked By: Date: Estimated Total Cost Estimated Total Cost (Rounded) Surface Improvements $ $ $ $ $ Storm Sewer Improvements $ $ 8.00 $ $ $ Project Cost / Foot Project Length (ft) Total Project Cost $ $ ,700,000

17 Appendix 5 UMore Development: Supply and Storage Analysis For Updated Area 1 and Area 2

18 Area1 & 2 Only Rosemount, MN Water Storage and Supply Analysis for Umore Development Assumptions: Only Area 1 and 2; Populations Served extrapolated from MCES 2040 Projections; Population projections do not include Umore Developments; no additional well included storage calculations; Area 1 has net developable acreage equal to and Area 2 has net developable acreage equal to 325 acres Water Use Projections & Storage Requirement Calculation Design Year Equation 109 gpcd 109 gpcd 109 gpcd 109 gpcd 109 gpcd 109 gpcd 109 gpcd 109 gpcd With 3 Hour gpm With 3 Hour gpm With 3 Hour gpm With 3 Hour gpm With 3 Hour gpm With 3 Hour gpm With 3 Hour gpm With 3 Hour gpm Includes Well 16 (2,000 gpm) Includes Well 16 (2,000 gpm) Includes Well 16 (2,000 gpm) Includes Well 16 (2,000 gpm) Includes Well 16 (2,000 gpm) Includes Well 16 (2,000 gpm) Includes Well 16 (2,000 gpm) Includes Well 16 (2,000 gpm) Estimated Population 23,710 24,137 27,040 27,620 28,200 28,780 29,360 29,937 A Per Capita Water Use (gpd/capita) B Umore Development Average Day Demand (Area 1 & 2) (gpd) 986, , , , , , , ,000 Average Day Water Use (gpd) 3,570,000 3,617,000 3,933,000 3,997,000 4,060,000 4,123,000 4,186,000 4,249,000 C= A*B Max/Avg Day Ratio D Maximum Day Water Use (gpd) 9,853,000 9,983,000 10,855,000 11,032,000 11,206,000 11,379,000 11,553,000 11,727,000 E= C*D Maximum Day Water Use (gpm) F= E»time Firm Pumping Firm Capacity (gpm) - Pumps to System G Design Fire Fighting Rate (gpm) H Fire Fighting Duration (hour) I Design Fire Fighting Volume (gal) 630, , , , , , , ,000 = H*I*60 TOTAL Coincident Demand (gpm) 10,342 10,433 11,038 11,161 11,282 11,402 11,523 11,644 J= F+H Required Draft From Storage (gpm) 2,742 2,833 3,438 3,561 3,682 3,802 3,923 4,044 K= J-G Adjusted Fire Fighting Storage (gallons) 494, , , , , , , ,000 L= K*I*60 Equalization Storage (gallons) 2,463,250 2,495,750 2,713,750 2,758,000 2,801,500 2,844,750 2,888,250 2,931,750 M= E*equl TOTAL Storage Need (gallons) 2,957,250 3,005,750 3,332,750 3,399,000 3,464,500 3,528,750 3,594,250 3,659,750 N= L+M Existing Elevated Storage (gallons) 3,000,000 3,000,000 3,000,000 3,000,000 3,000,000 3,000,000 3,000,000 3,000,000 P Additional Storage Need (gallons) ok 5, , , , , , ,750 Q= N-P time equl Page 1