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CR 09-031 Approve Facility Plan for Lift Station No. 1GITY OF ia N April 7, 2009 OPKINS Council Report 2009 -031 Approve Facility Plan for Lift Station No. 1 Proposed Action Staff recommends adoption of the following motion: Approve Resolution 2009 -017 Resolution Approvinlz Facility Plan for Lift Station No. 4. Overview The 2008 Comprehensive Utility Plan identifies the abandonment of Lift Station No 1 on 21 Avenue as a necessary improvement needed within the next few years. With the availability of federal stimulus dollars for water and wastewater projects, it is prudent to apply to this funding source. Approval of the attached facility plan is a necessary component of the application process. The facility plan recommends the abandonment of this lift station to be replaced with an 8" gravity sewer that connects to a City of Minnetonka sewer trunk in Shady Oak Road. In addition to removing an out of date lift station, the project will reduce Inflow into the sanitary sewer system when Shady Oak Pond overflows into the lift station. The estimated projects costs are $286,185. Funding will be from the State Revolving Fund which provides assistance for water pollution control projects. In Minnesota, the fund provides low interest loans and grants for these projects. Given the additional resources available because of the federal stimulus package, lower interest rates or higher grant amounts are anticipated. The exact mix will not be known until the funding is awarded. A decision about proceeding with the project will be made at that time. Supporting Information • Facility Plan Text • Resolution 2009 -017 J Bradford, P.E. 4� Financial Impact: _$�Q Budgeted: Y/N N/A Source: Related Documents (CIP, ERP, etc.): 2008 Comp Utility Plan Notes: LIFT STATION NO. 1 ABANDONMENT FACILITY PLAN HOPKINS, MINNESOTA MARCH 2009 T16.100824 I hereby certify that this plan, specification or report was prepared by me or under my direct supervision, and that I am a duly Licensed Professional Engineer under the laws of the State of Minnesota. Signature: �� ��� Typed or Printed Name: Marcus A. Thomas Date 3 /s1 6 7 Reg. No. 26499 BOLTON & MENK, INC. CONSULTING ENGINEERS & LAND SURVEYORS �v k TABLE OF CONTENTS Section Page 1. General ............................................................. ............................... 1 2. Existing Conditions .......................................... ............................... 1 3. Proposed Improvements 1 4. Recommendations, Financing, and Implementation ....................... 3 LIST OF APPENDICES Appendix Page A. Estimated Cost of Improvements ..................... ............................... 4 B. Figures ............................................................. ............................... 6 C. Draft EIW ........................................................ ............................... 9 D. Information Presented at the Public Hearing ... ............................... 18 E. Council Resolution .......................................... ............................... 31 F. Agreement with City of Minnetonka ............... ............................... 32 F. Geotechnical Evaluation of Site ...................... ............................... 34 City of Hopkins, Minnesota — TI 6.100824 Lift Station No. 1 Abandonment Facility Plan Page i Prepared by Bolton & Menk, Inc. 1. General This report is intended to provide the City of Hopkins, Minnesota with necessary information regarding the replacement of City's Lift Station No. 1. The purpose of this report is to assist the City in determining priorities as well as plan, fund, and construct a feasible solution. 2. Existing Conditions Lift Station No. 1 serves an area in Hopkins that is fully developed with 40 single family homes. This area is zoned type R -1 by the City of Hopkins. Based on the "Engineering Guidelines" for the City, this type of zoning area has a typical density of 3 persons per home. No land use changes are anticipated in this area. The City of Hopkins currently operates a sanitary sewer lift station (No. 1) at the intersection of 2 nd Street North and 21 Avenue North on the north side of Shady Oak Pond. This lift station serves 40 single family residential properties along Shady Oak Road, West Park Road, and 21 Avenue North. Effluent from this facility flows east to 20 Avenue North where it enters a gravity sanitary sewer main. The Hopkins gravity system conveys these flows to a Met Council Lift Station 27. Ultimately, the wastewater generated by the study area is treated at the Met Council Metropolitan Wastewater Treatment Plant. Lift Station No. 1 has been in service since 1957 and is approaching the end of its useful lifespan. Furthermore, the existing forcemain exiting the lift station has also been in place since 1957 and will require replacement in the near future. The area served by the lift station is fully developed and there are no anticipated land use changes or sewer extensions, therefore, there is no projected increase in the sewer flows to the lift station. 3. Proposed Improvements Improvement options considered for Lift Station No. 1 included 1) replacement of Lift Station No. 1, and 2) rerouting the flows with a gravity sewer line to an existing City of Minnetonka trunk sewer line along Shady Oak Road. The initial construction costs of these two options are comparable; however, the life cycle costs of operation and maintenance for the lift station replacement would far outweigh life cycle costs, if any, involved with the City of Hopkins, Minnesota — T16.100824 Page 1 Lift Station No. 1 Abandonment Facility Plan Prepared by Bolton & Menk, Inc. gravity sanitary sewer proposal. Therefore, it was decided the gravity sanitary sewer 0 r extension would be further investigated. The installation of a gravity sewer line will need to maintain existing flows from the 40 residential properties currently served by the lift station. As previously mentioned, there is no projected growth in the sewer flows in the service area. These flows are sufficiently contained within an 8" sanitary sewer main entering the lift station. Therefore, a proposed 8" gravity line alternative would flow at a grade of 0.70% along 2 nd Street North from 21" Avenue North to Shady Oak Road where a 54" trunk sewer line operated by the City of Minnetonka is located with sufficient depth. During preparation of a preliminary engineering report in February of 2005, it was determined the 54" gravity sewer has sufficient additional capacity to serve the area currently served by Lift Station No. 1. The rerouting of the sewer flow into the City of Minnetonka trunk sewer system will result in a change in the treatment facility serving the area. Sewer flows are currently treated at the Metropolitan Council's Metropolitan Wastewater Treatment Plant. After the sewer flows are rerouted the flows will be treated by the Blue Lake Wastewater Treatment Plant. The abandonment of Lift Station No. 1 will provide notable environmental improvements. It will eliminate the risk of potential sewer flow backups due to mechanical failure within the lift station. Such overflows would quickly and completely flow into Shady Oak Pond due to the topography of the area. In addition, the elimination of Lift Station No. 1 will reduce some infiltration by replacing the lift station structure, approximately 550 feet of existing sewer pipe, and two existing manholes with new watertight pipe and manholes. During the construction process, bypass pumping will be done as required to maintain service to the affected properties. The gravity sewer solution will also eliminate significant inflows during Shady Oak Pond flooding events. During flooding events the pond has caused inflows in the system of more than 60,000 gallons per day in addition to the typical outflows from the service area. Given the proposed improvements are to be installed underground and watertight castings are to be installed to minimize inflow, the system will be operable during 25 -year and 100 -year flood events. City of Hopkins, Minnesota — TI 6.100824 Lift Station No. I Abandonment Facility Plan Page 2 Prepared by Bolton & Menk, Inc. I I I 1 1 I 1 I i I i 1 1 1 1 I 1 I 1 I 1 I 4. Recommendations, Financing, and Implementation In the previous sections the existing and proposed sanitary sewer system in the study area was analyzed in terms of condition and service needs. It was determined that a gravity sanitary sewer connection to the City of Minnetonka trunk sewer provides a more cost - effective long term solution than replacement of the lift station. It was also determined that the lift station does need improvements if it is to be reliable and relieve the concern regarding potential backups. Based on these conditions, it is recommended the City of Hopkins construct the previously discussed proposed improvements as funding becomes available. The estimated total cost of the proposed improvements is $286,185.00. A more specific breakdown of the estimated costs for each item is provided in the appendix. Financing options include applying for a State Revolving Fund load through the Public Facilities Authority, the City Sewer Fund, selling bonds, or assessing to benefitting properties. A likely source of funding for this project is the State Revolving Fund. The State Revolving Fund was created under a provision from the Federal Clean Water Act to provide financial assistance for water pollution control projects. Minnesota's revolving loan program provides loans to municipalities for planning, design, and construction of wastewater facilities. The Department of Trade and Economic Development's Public Facilities Authority administrates the loan application and distribution of funds. The loans are available for a twenty -year period. Due to the recent economic stimulus programs instituted by the Federal government, the fund has an increased quantity of loan dollars to distribute. This project may be eligible for funding as it may meet the minimum criteria after it is lowered by the stimulus. An estimated schedule for implementation of these improvements is shown on the following page. The schedule assumes funding is available through the Revolving Loan Fund in 2009. City of Hopkins, Minnesota — T16.100824 Lift Station No. 1 Abandonment Facility Plan Page 3 Prepared by Bolton & Menk, Inc. City of Hopkins, Minnesota - TI6.100824 Page 4 Lift Station No. 1 Abandonment Facility Plan Prepared by Bolton & Menk, Inc. Item Date 1. Approve Facility Plan and Submit to MPCA March 2009 2. Receive Confirmation of Funding from MPCA April 2009 3. Prepare Plans and Specifications April 2009 4. Authorize Bids May 2009 5. Award Project June 2009 6. Construction June - July 2009 City of Hopkins, Minnesota - TI6.100824 Page 4 Lift Station No. 1 Abandonment Facility Plan Prepared by Bolton & Menk, Inc. Appendix A Estimated Cost of Improvements PRELIMINARY ENGINEER'S ESTIMATE LIFT STATION NO. 1 BYPASS IMPROVEMENTS CITY OF HOPKINS, MINNESOTA BMI PROJECT NO. T16.100824 F:\ 1 \Excel \[LS 1 Prelim Estimate.xls]Full Project Cost Est. March 2, 2009 ITEM NO. ITEM ESTIMATED BID QUANTITY UNIT UNIT PRICE TOTAL 1 MOBILIZATION 1 LS $6,100.00 $6,100.00 2 3 4 5 REMOVE CONCRETE CURB & GUTTER REMOVE DRIVEWAY PAVEMENT MILL BITUMINOUS PAVEMENT FULL DEPTH COMMON EXCAVATION EV P 1080 25 1960 540 LIN FT SQ YD SQ YD CU YD $4.50 $4.00 $3.25 $17.00 $4,860.00 $100.00 $6,370.00 $9 6 SUBGRADE EXCAVATION (EV) 400 CU YD $17.00 $6,800.00 7 BORROW MATERIAL FOR SUBGRADE EXCAVATION CV 400 CU YD $14.00 $5,600.00 8 CLASS V AGGREGATE BASE CV 730 CU YD $19.00 $13,870.00 9 1.5" BITUMINOUS WEAR COURSE 230 TON $62.00 $14,260.00 10 2.5" BITUMINOUS NON -WEAR COURSE 350 TON $60.00 $21 11 BITUMINOUS MATERIAL FOR TACK COAT 120 GAL $3.25 $390.00 12 8618 CONCRETE CURB & GUTTER 1080 LIN FT $15.00 $16,200.00 13 LAWN TYPE SOD 840 SQ YD $5.50 $4,620.00 14 TOPSOIL BORROW CV 70 CU YD $16.00 $1,120.00 15 ADJUST VALVE BOX 3 EACH $300.00 $900.00 16 SILT FENCE 600 LIN FT $2.25 $1,350.00 17 FLOATING SILT CURTAIN 600 LIN FT $4.00 $2,400.00 18 TRAFFIC CONTROL 1 LS $10,000.00 $10,000.00 19 PAVEMENT STRIPING 1 LS $500.00 $500.00 20 6" CONCRETE DRIVEWAY PAVEMENT 25 SQYD1 $60.00 $1,500.00 21 REMOVE EXISTING SANITARY SEWER 500 LIN FT $5.00 $2 22 REMOVE EXISTING SANITARY MANHOLE 2 EACH $500.00 $1,000.00 23 CONNECT TO EXISTING SANITARY MANHOLE 1 EACH $500.00 $500.00 24 CONNECT TO EXISTING TRUNK SEWER LINE 1 EACH $5,000.00 $5,000.0 25 CONNECT TO EXISTING LATERAL SEWER LINE 2 EACH $300.00 $600.00 26 8" PVC, SDR -35 590 LIN FT $19.00 $11,210.00 27 SANITARY SEWER MANHOLE - 48" 40 LIN FT $300.00 $12 28 SANITARY SEWER MANHOLE - 96" 8 LIN FT $700.00 $5,600.00 29 SANITARY SEWER MANHOLE CASTING 3 EACH $300.00 $900.00 30 ADJUST CASTING 1 EACH $275.00 $275.00 31 FOUNDATION ROCK CV 90 CU YD $55.00 $4,950.00 32 GEOTEXTILE FABRIC FOR TRENCH 270 SQ YD $4.00 $1,080.00 33 DEWATERING 590 LIN FT $60.00 $35,400.00 SUBTOTAL $208,135.00 CONTINGENCIES 10 $20,810.00 SUBTOTAL CONSTRUCTION COSTS $228,945.00 ENGINEERING & ADMINISTRATION 25% $57,240.00 TOTAL $286,185.00 CITY OF HOPKINS HENNEPIN COUNTY, MINNESOTA RESOLUTION NO. 2009 -017 RESOLUTION APPROVING FACILTY PLAN FOR LIFT STATION NO. 1 WHEREAS, the City of Hopkins completed a comprehensive utility plan in 2008, and WHEREAS, the utility plan recommends the abandonment of this lift station, and WHEREAS, the use of MN State Revolving Fund financing requires the approval of a facility plan and that such plan has been completed and reviewed by the public and the City Council, NOW, THEREFORE, BE IT RESOLVED, by the City Council of the City of Hopkins, Minnesota: 1. The City of Hopkins approves the facility plan for Lift Station No. 1 Abandonment dated March 2009. Adopted by the City Council of the City of Hopkins this 7 th day of April, 2009. In ATTEST: Eugene J. Maxwell, Mayor Terry Obermaier, City Clerk