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Memo - SAV Connection_2015_0818 Page 2 of 3 Two potential options for connection to the City of Minneapolis water system by Saint Anthony Village were identified for evaluation: 1. Connection to Pipeline 16 at one of several possible locations between 40th Avenue Northeast and Lowry Avenue Northeast. 2. Providing a connection to the outlet piping of the Hilltop reservoirs at Stinson Boulevard between 45th Avenue NE (County Road E) and 5th Street NW, and routing a new water main South on Stinson, East on County E, and South on Silver Lake Road and connecting with the existing 12” Saint Anthony Village water main. This new water main could possibly be combined with a main serving the City of New Brighton. The length of the main required would be approximately 4,400 feet along this route. Because of the length of the main and the significance of the roads along the route, this option was not considered further. Four potential locations for connection to Pipeline 16 were evaluated, with any number of other locations potentially being viable for consideration. Further Discussion of Option 1 Pipeline 16 is a 48-inch welded steel water main constructed 1949-1950, which begins at the Hilltop Reservoirs. There are a total of four interconnected reservoirs at Hilltop with a total capacity of 72 million gallons. The pressure for Pipeline 16 under normal operation is controlled by the level in the Hilltop Reservoirs and regulated by a control valve located downstream where the pipeline runs through the Columbia Heights treatment campus. The City of Minneapolis has adequate pumping capacity with sufficient redundancy to be able to continue to maintain sufficient levels in the Hilltop Reservoirs to accommodate additional consumption as considered in this study. Pipeline 16 is part of the City of Minneapolis outer transmission main loop and is routed south along Arthur Street, Benjamin Street, and Stinson Boulevard to Lowry Avenue NE, and continues south. Pipeline 16 was field-lined in 1963 with cement mortar. Elevations and pressures are as follows:  Hilltop Reservoirs Water Surface Elevation o Range: 1054 -1074 feet above Mean Sea Level (MSL) (overflow)  Pipeline 16 Control Valve at Columbia Heights Campus o Outlet Pressure HGL  Approximate Range = 1045 – 1061 feet above MSL  Normal Operation = 1050 feet above MSL Table 1 lists several possible connection points to Pipeline 16 giving ground elevation at these points, as well as the corresponding approximate hydraulic grade lines based on the normal control valve outlet pressure of 1050 feet MSL. Head losses are not included, as the flow in Pipeline 16 is typ ically in the range of 25-35 MGD and head losses for purposes of this analysis are relatively small. Also included are approximate distances to potential points of connection to the Saint Anthony distribution system. It is assumed given the size of the Pipeline 16 that further evaluation of residual pressures is unnecessary at this time.