Agenda - Parks and Recreation Commission - 04/10/2014

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2. Drill monitoring wells at an easement site within the Ramsey Town Center. The objective of these wells is to monitor both the Ironton — Galesville aquifer and the drift aquifer water levels. 3. Drill monitoring wells adjacent to Lake Itasca. The objective of these wells is to monitor both of the Ironton — Galesville and drift aquifer water levels. Appendix D contains the monitoring well site map and plan for reference. 2. Surface Water Sources Ramsey is bordered to the south by the Mississippi River. Both the Minneapolis Water Department and The St. Paul Regional Water Services obtain water for drinking water purposes from the Mississippi River. Typically, smaller communities have not found it cost effective to obtain water from this source due to the treatment requirements of a surface water source. However, with the increasing demand being placed on local aquifers, and the decreasing costs of advanced membrane technologies, the Mississippi River is a viable option for providing water to the City of Ramsey. Based on discussions with MnDNR staff, treatment of this source will be evaluated, with a groundwater source backup based on the current well system. Surface water would be obtained indirectly from the river utilizing a riverbank infiltration system. This system collects water from the river utilizing vertical wells, horizontal collectors or infiltration galleries, located near the riverbank. Water is pumped from these collection devices, lowering the local water table below the river stage. This establishes a hydraulic gradient into the aquifer, providing for a high rate sustainable yield from the collection area. Water is then pumped via a raw water transmission main to a surface water treatment facility. An approximate location for the collection area and raw water transmission main are shown on Figure 5.1. City of Ramsey, Minnesota — M21.34343 Page 5-2 Water System Study Prepared by Bolton & Menk, Inc.