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1 NSVI Morse Pond Extension Nine Springs Valley Interceptor Morse Pond Extension Project Purpose: The purpose of this project is to extend the public sanitary sewerage system to provide service for lands to be developed in the cities of Madison and Verona near the intersection of County Trunk Highway PD (CTH PD) and County Trunk Highway M (CTH M). Project Proposer/Champion: Todd Gebert Department: Engineering Project Involvement: The Engineering Departmentt will provide overall management of the project, including the key elements of the interceptor design. Preparation of plans and specifications and other aspects of the design will be completed by a consultant (MSA Professional Services). MSA is also designing the roadway improvements at CTH M and CTH PD in partnership with the City of Madison, the City of Verona, and Dane County. Construction of the interceptor sewer will be integrated into the roadway improvement project. Page 1 of 5

2 NSVI Morse Pond Extension Project History and Status: In 1996 the City of Verona and the City of Madison entered into an intergovernmental cooperation agreement for development of lands within the proposed service area. Among other things, the agreement delineated the ultimate jurisdictional boundaries between the municipalities in this area, provided for open space corridors along CTH PD and CTH M, and set development standards for a portion of the service area known as the Five Points Planning Area to ensure that future development is compatible with designated open spaces. The current agreement is set to expire in 2016 and both municipalities have expressed interest in establishing a new agreement. The City of Verona has identified in its North Neighborhood Development Plan a need to provide sanitary sewer service to lands in the southwest quadrant of CTH PD and CTH M. The majority of said lands are in the Town of Verona but will likely be annexed to the City of Verona prior to development. Approximately 274 acres of lands in the North Neighborhood Development Plan lying south of CTH PD were added to the Verona Urban Service Area in February of The City of Madison has a need to provide sewer service to lands in the northeast quadrant of CTH PD and CTH M, west and east of Raymond Road. At this time there are no plans to serve the University Ridge Golf Course and cross country facilities which are operated by the University of Wisconsin and are located west of Morse Pond and north of CTH PD. Sewer service can be provided by extending approximately 3,200 feet of new sanitary sewer along Raymond Road from MMSD s Nine Springs Valley Interceptor (NSVI) Midtown Extension to the southwest corner of CTH PD and CTH M. The preliminary route of the interceptor along Raymond Road has been completed by MSA and the preliminary design is underway. Final design documents are to be completed in 2016, with construction anticipated to begin in 2017 and extending into Options: a. Description: The proposed project involves the construction of approximately 3,200 feet of new sanitary sewer to be installed from MMSD s existing NSVI Midtown Extension to the southwest corner of CTH PD and CTH M. The new sewer will generally be located along Raymond Road (as shown in attached Figure 1) and will provide service for lands in the City of Madison and lands south of CTH PD that will likely be annexed to the City of Verona. The sewer construction will be coordinated with the reconstruction of CTH M from Cross Country Road in the City of Verona to Flagstone Drive in the City of Madison. Page 2 of 5

3 Page 3 of 5 NSVI Morse Pond Extension It should be noted that a large portion of the Morse Pond drainage basin which is shown in Figure 1 will not be served. Lands which will not be served include the University Ridge Golf Course and adjacent cross country facilities north of CTH PD, areas designated as permanent open space in the 1996 intergovernmental agreement between the City of Verona and the City of Madison, and other environmental corridors that are identified during the development process. b. Alternatives Alternative 1 Construct MMSD interceptor A new gravity interceptor will be constructed as outlined in Part a. above. See attached Figure 1 for route of new interceptor. Alternative 2 Do not construct MMSD interceptor Under this option MMSD will not construct a regional interceptor to serve any of the lands to be developed. City of Madison lands to the north of CTH PD will be served through local sewers connected to MMSD s NSVI Midtown Extension. Lands to the south of CTH PD and west of CTH M cannot be served by gravity sewer under this option. Local sewers serving this area will drain to a municipally owned lift station and flows will be pumped south to the City of Verona s existing wastewater conveyance system. Further investigation will be needed to assess the capacity of the City s downstream collection system and the feasibility of this option. For purposes of performing an economic analysis for this alternative, it is assumed that at least 3,600 feet of new gravity sewer will need to be provided. A preliminary layout for the required local improvements is shown in attached Figure 2. c. Key Risks and Issues Alternative 1. There are few risks associated with this alternative as gravity sewer service is reliable and thus is MMSD s preferred method of conveying wastewater. Temporary environmental impacts such as soil disturbance will be experienced during construction. Additionally there will be some social impacts related to vehicular traffic as the project area is located within a heavily traveled transportation corridor. Both impacts will be greatly mitigated by coordinating the construction of the interceptor with the highway improvement project. Alternative 2. Providing sanitary sewer service to the lands in the southwest quadrant of CTH PD and CTH M through a lift station presents a greater risk of sanitary sewer overflows than the gravity option outlined in Alternative 1. Lift

4 NSVI Morse Pond Extension stations are susceptible to failure due to interruptions in power and/or equipment malfunction and are energy intensive. Lift stations are generally not received well by the public due to their visual appearance, unpleasant odors, and periodic visits by operations and maintenance personnel. Selection of Alternative 2 does not conform to District policy regarding the construction and use of District interceptors. The policy states that the District shall construct and operate an interceptor only when such interceptor will serve at least two municipalities. In this instance a pump station located south and west of CTH M and CTH PD will serve only the City of Verona and thus will likely be owned by the City, not MMSD. d. Economic Analysis Please see the attached 50 year life cycle cost estimate. A summary of present worth costs is provided in the following table: Capital Cost Replacement & O&M Costs Salvage Value Total Present Worth Alternative 1 $1,431,000 $39,000 $103,000 $1,367,000 Alternative 2 $1,686,000 $629,000 $189,000 $2,126,000 Recommended Option Staff recommends Alternative 1 due to the reliability and cost effectiveness of providing gravity sewer service for the subject lands and for its conformance with District policy regarding the construction and use of District interceptors. Project Schedule: Start Date Completion Date Planning Design January 2015 August 2016 Bid Date March 2017 April 2017 Construction May 2017 March 2018 Page 4 of 5

5 NSVI Morse Pond Extension Financial Summary (2016 dollars): Total Project Cost District Staff $110,000 Consultant $55,000 Contractor $1,270,000 Total $1,435,000 Fiscal Year Allocation (2016 dollars): District staff $0 $50,000 $50,000 $10,000 Consultant $10,000 $5,000 $30,000 $10,000 Construction $0 $0 $950,000 $320,000 Total $10,000 $55,000 $1,030,000 $340,000 Page 5 of 5

6 NSVI - Midtown Extension City of Madison Thomas Zimmer Cross Country Course University Ridge Golf Course Morse Pond Raymond Rd CTH PD CTH M Town of Verona Morse Pond Basin Morse Pond Extension City of Madison City of Verona City of Verona Town of Verona Urban Service Boundary Madison Metropolitan Sewerage District Figure 1: Construct NSVI - Morse Pond Extension (Alternative 1) Feet Prepared by: Todd Gebert Date: 8/23/13

7 NSVI - Midtown Extension University Ridge Golf Course City of Madison CTH M Thomas Zimmer Cross Country Course Morse Pond Raymond Rd CTH PD Town of Verona Morse Pond Basin City of Madison Madison Sewer City of Verona City of Verona Verona Sewer Verona Force Main Town of Verona Urban Service Boundary Verona LS Madison Metropolitan Sewerage District Figure 2: Do Not Construct NSVI - Morse Pond Extension (Alternative 2) Feet Prepared by: Todd Gebert Date: 8/23/13

8 50 YEAR PRESENT WORTH COST ANALYSIS FOR NSVI MORSE POND EXTENSION Present Worth Analysis Year 2016 Analysis Period (yrs) 50 End of Analysis Year 2066 Capital Cost Replacement Costs O&M Costs Salvage Value Cost in Year 2016 Present Replacement 2016 Present 2016 Present Year 2016 Present Total 2016 Project Description Year Constructed Worth Year Worth Worth 2066 Worth Present Worth Alternative 1 Construct MMSD Interceptor New Interceptor ,478,000 1,431, , , ,000 1,367,000 Alternative 2 Do Not Construct MMSD Interceptor Local Sanitary Sewer (City of Madison) , , , ,000 27, ,000 Verona Lift Station (includes annual O&M and energy) , , , ,000 31, ,000 Verona Force Main , , , ,000 21, ,000 Verona Gravity Main , , , ,000 42, ,000 Pump Replacement for Verona Lift Station , ,000 37,000 23,000 Electrical Upgrade for Verona Lift Station , ,000 31,000 19,000 TOTALS 1,741,000 1,686, , , ,000 2,126,000 Assumptions and Notes: (1). Base interest rate = 3.25% (2). Construction cost escalation rate = 3.00% (3). Interceptor & Forcemain Service Life (yrs) = 75 (4). Pump Station Service Life (yrs) = 75 (5). Pump/Drive and Electrical Controls Service Life (yrs) = 40 (6). Annual O&M interceptor cost ($/ft) = 0.25 (7). Annual O&M forcemain cost ($/ft) = 0.25 (8). Base interest rate excludes rate of inflation. Assume construction costs do not escalate beyond those due to inflation. (9). Annual lift station maintenance costs estimated at $5,000 per year. Based on MMSD records for maintenance of non District stations. (10). Annual lift station energy costs estimated at $3,400 per year.

9 50 YEAR PRESENT WORTH COST ANALYSIS FOR NSVI MORSE POND EXTENSION Estimated Unit Total No. Description Footnote Quantity Units Cost Cost Alternative 1 Construct MMSD Interceptor Major Capital Costs for NSVI Morse Pond Extension 1 Mobilization 1 L.S. $25,000 $25,000 2 Sanitary Sewer 18" Thick Wall PVC less than 20' Deep 1,040 L.F. $190 $197,600 3 Sanitary Sewer 18" Thick Wall PVC 20' 30' Deep 1,580 L.F. $230 $363,400 4 Sanitary Sewer 18" Thick Wall PVC 30' 40' Deep 585 L.F. $380 $222,300 5 Core Existing Manhole and Provide Bench 1 L.S. $10,000 $10,000 6 Sanitary Manhole Complete 6' Diameter up to 21' Deep 3 EACH $20,000 $60,000 7 Sanitary Manhole Complete 6' Diameter 21' 25' Deep 4 EACH $25,000 $100,000 8 Sanitary Manhole Complete 6' Diameter 35' 40' Deep 1 EACH $40,000 $40,000 9 Trench Backfill 3,205 L.F. $12 $38,460 Sub Total $1,056,760 Contingencies (5) 20% $211,352 Construction Total $1,270,000 Engineering 12% $150,000 Design 1.3% $17, Project Cost $1,435,000 Alternative 2 Do Not Construct MMSD Interceptor City of Madison Local Sewer Sanitary Sewer on Raymond Road (2) 2,250 L.F. $100 $225,000 4' Diameter Manholes (2) 6 EACH $10,000 $60,000 Sub Total $285,000 Contingencies 20% $57,000 Construction Total $340,000 Engineering 10% $34, Project Cost $375,000 City of Verona Lift Station & Local Sewer Lift Station (3) 1 L.S. $330,000 $330,000 Force Main 2,800 L.F. $80 $224,000 12" Gravity Main (4) 3,600 L.F. $100 $360,000 4' Diameter Manholes 10 EACH $8,250 $82,500 Sub Total $996,500 Contingencies 20% $199,300 Construction Total $1,195,000 Engineering 10% $119, Project Cost $1,315,000 Notes: (1). All costs in 2016 dollars. (2). Assumes City of Madison sewer built along Raymond Road from NSVI Midtown Extension to point north of CTH PD (deep sewer). (3). Assume City of Verona lift station constructed at southwest corner of CTH PD and CTH M, sized to serve approximately 440 acres of land in City of Verona. (4). Length of required gravity main roughly estimated by reviewing City of Verona sewer system records. Detailed capacity analysis of Verona system is required to obtain a more accurate estimate. (5). Contingency to allow for unassigned road restoration and other costs which may be required as part of participation in WDOT project.