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SECTION 4 - PROJECT DESCRIPTION <br />ANALYSIS OF ALTERNATIVES <br />The existing South well field's main water transmission line was constructed around 1933 as a <br />WPA project. It is constructed of cast iron and is in very poor condition. Recent sampling of the <br />pipeline by the City Water Department and Honeywell Building Solutions indicated a significant <br />amount of internal tuberculation (internal scale build -up), pressure drop and pin -hole leaks. This <br />sampling included water quality tests, pumping (energy) head loss testing and removal of a <br />section of pipe for visual inspection. These conditions contribute to less than desired water <br />quality, excess pumping energy, serious risk for pipeline failures and water loss. It was <br />determined that replacement of this critical infrastructure pipeline is the only viable alternative, <br />and that implementation should proceed immediately. The pipe is approximately 34,200 feet in <br />length. WSRA funding will be used for design, permitting, construction and project management <br />costs. <br />Three alternatives were considered: <br />A. Replace Southern Transmission Line with Polyvinyl Chloride (PVC) Pipe <br />B. Replace the Southern Transmission Line with Ductile Iron Pipe (DIP) <br />C. No Action <br />The three alternatives were evaluated for multiple factors to separate them based on capital costs, <br />operating costs, impacts to the environment, institutional requirements, and'special <br />considerations. <br />ALTERNATIVE A — REPLACE SOUTHERN RAW WATER TRANSMISSION LINE WITH PVC <br />The first alternative evaluates replacing the existing Southern Raw Water Transmission line with <br />PVC pipe. The approximate length of replacement is 34,200 linear feet (LF). The existing wells in <br />the South well field will be reconnected to the new transmission line. Water production will not be <br />changed, but water conservation and energy efficiency will be increased. Design flows for the wells <br />in the South well field are summarized in Table 1. The South well field can produce up to 5.19 ac/ft <br />or 1.69 MG per day and supply approximately 88% of the average daily demand for Lamar. <br />Table 1 — Design Flows <br />Source <br />Design <br />Flow [gpm] <br />Notes <br />Well No. 22 <br />280 <br />Layne 6GM w/ VFD (15 hp, 3600 rpm SS motor) <br />Well No. 23 1 <br />120 <br />Well No. 24 1 <br />135 1 <br />Grundfos 15OS500 -2 (5 hp, 3600 rpm motor) <br />City of Lamar Raw Water Feasibility Study — Colorado Water Conservation Board 6 <br />