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CASE # WATER sTuDY UPDATE AND 1994 WATER SYSTEM IMPROVEMENTS By: Steven Jankowski, City Engineer Background: As you may .n~call, the City entered into a contract with Bonestroo, Rosene, Anderlik and Associates tO~ perform a comprehensive study of the City's water system. The major impetus for tl~is study was concern of a water shortage for the 1994 summer season. At this time, thei consultant is awaiting finalization of the water study, pending review of several repor~ sections by State agencies which are implementing new requirements for such studies. " However, the major concern, namely the adequacy of the system supply, has been addressed antl some conclusions are presently available. Early in the study, it was anticipated that a possible solution to the water utilities short-term need for additional water supply could be addressed with the connection to the City of Anoka's water system. The consultant ha~ prepared Table 1 which summarizes the next six years of projected water demand and ®mpares that with the City's existing supply. You will note that in order to meet the pro~pcted demand, three wells would need to be constructed within this time period, with Se first well being completed so that it is in service in 1994. In contrast, Table 2 proviCles a well construction schedule for meeting the water demands utilizing the City of Anok~'s system for peak periods during the summer months. You will note that this scenario ~eliminates the need to construct a well until 1997, and deals the need to construct one ~ell during this time period. I have prepared Table 3 which is a summary of cash flows over the six-year period for both of the alternatives considered. The financial advantage of the Anoka interconnect is quite obvious. In addition to [he financial advantage of the interconnect with Anoka, there is also two other significant advantages associated with this interconnec(i' First it provides the City utility with an altern~ five source should some catastrophe affect our singIe existing well house. Secondly, this connection would provide a second feed to the entire portion of the system located west bf Tungsten Street N.W. and County Road #116. At the present time, a single main bW. ak would eliminate water supply to all remaining down-stream connections. It should also be noted that the City of Anoka's system operates at a hydraulic grade slightly lower~than the City of Ramsey's. When water is required from the City of Anoka, it would be neCessary to manually close a valve at one or more locations to separate the two systems. The area receiving water from the City of Anoka would then operate at a pressure approximatel9 12 pounds lower than the existing. While the lower pressure may be noticeable, ar~as serviced by Anoka's supply would still operate at pressures above 65 psi, which is well ~tbove the 40 psi recommended minimum system pressure. It is anticipated that fn'e flows ~at the reduced pressure will still be within acceptable ranges. I have been in,Contact with the City of Anoka regarding .this connection, and their City Staff is agreeable v~i~'th the concept. We wouid need to have further conversations with the City of Anoka to establish an agreement regarding the sale of the water. In addition torthe interconnect with the City of Anoka, I feel it is also prudent to ensure entering the 1994 peak demand season as well prepared as possible. Well No. 1 is our largest producer at 500 gallons per minute. This is a line shaft driven turbine pump which has been in service since 1985. It is standard practice to periodically pull the line shaft pumps and inspect the pump for wear and the pump column for signs of corrosion. The