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City of Lamar Agenda Item29a September 13, 2013 (Updated September 26, 2013) Page 3 of 8 The City has groundwater rights to 43 wells for use in the water supply system. Of these, 29 are active wells used for potable use. Raw water from the wells is pumped to a chlorination building and stored in above grade storage tanks. The remaining wells are scattered throughout the City for irrigation of parks, for use at the City's maintenance shop, and for use at the airport. Project Description The existing South well field's main water transmission line is constructed of cast iron and is in very poor condition. Recent sampling of the pipeline by the City Water Department and Honeywell Building Solutions indicated a significant amount of scale build -up, pressure drop, and pin -hole leaks. This sampling included water quality tests, pumping (energy) head loss testing, and removal of a section of pipe for visual inspection. The condition of the pipe contributes to less than desired water quality, excess pumping energy, serious risk for pipeline failures and water loss. It was determined that replacement of this critical infrastructure pipeline is the only viable alternative, and that implementation should proceed immediately. Three alternatives were considered: Selected Alternative 1- Replace Southern Transmission Line with Polyvinyl Chloride (PVC) Pipe: This alternative evaluated replacing the transmission line with 34,200 linear feet of PVC pipe to conserve water and improve energy efficiency. Replacing the line with 16 -inch PVC offers superior corrosion resistance, ease of installation, and is substantially cheaper than Ductile Iron Pipe. Alternative 2 - Replace the Southern Transmission Line with Ductile Iron Pipe (DIP): This alternative evaluated replacing the transmission line with DIP. The price DIP is more expensive than PVC; therefore, this alternative was eliminated based on cost. Alternative 3 — No Action: This alternative was not considered a viable option due to poor condition of the existing transmission main. The hundreds of AF of lost water every year makes this project the most urgent water improvement project for the City. The superior water quality also allows the City to reduce water treatment costs by using more water from the South well field source. TABLE 1: TOTAL PROJECT COST SUMMARY Task Cost Pipeline Construction $1,360,500 Final Design and Construction Management $369,300 Permitting $13,600 Contingency $226,600 Total $1,970,000 Schedule: The Project schedule is as follows: bid the Project in November of 2013; construction in the winter /spring of 2013/14.