Agenda - Council - 10/08/2019 - Laserfiche WebLink

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Our Mistioi}: To work together to reipoiibly grew our comma nityr, and to provide quality, cent-oliBcdwe, and efficient government services. CC Regular Session 7. 3. Meeting Date: 10/08/2019 By: Bruce Westby, Engineering/Public Works Information Title: Adopt Resolution #19-248 Accepting Proposals and Awarding Contract for Improvement Project #19-12, Centralized Water Treatment Facility Preliminary Design Report Purpose/Background: Purpose: The purpose of this case it to adopt Resolution #19-248 accepting proposals and awarding a contract for Improvement Project #19-12, Centralized Water Treatment Facility Preliminary Design Report. Background: The existing water supply source for the City of Ramsey's water supply system is the Tunnel City/Wonewoc (TCW) aquifer, formerly known as the Franconia -Ironton -Galesville (FIG) aquifer. Water is drawn from the TCW aquifer through eight (8) groundwater wells, seven (7) of which are currently being utilized to provide potable water. The maximum capacity of the combined municipal wells is 10.9 million gallons per day (MGD). Two additional wells are proposed to be constructed in the years 2023 and 2028, which is intended to supply water to all municipal water system users to the year 2040 based on projected City growth. The City's groundwater supply wells have historically provided groundwater of good quality and in adequate quantity. However, in 2019 the Minnesota Department of Health informed the City that several of its groundwater supply wells are producing concentrations of manganese that exceed the recommended Secondary Drinking Water Standards. The City does not currently treat its municipal water supply for manganese so as a short-term solution the City immediately started pumping water only from the three wells with the lowest concentrations of manganese to maintain manganese concentrations below the recommended Secondary Drinking Water Standards. While this approach worked okay this summer, heavy irrigation use was not observed this year due to the large amount of rain received, which prevented the need to run other wells in significant amounts. This might not be the case in future years so Staff is requesting Council authorization to utilize SEH, Inc. to complete the requested professional services over the next eight months. It is important to note that the City wells with the lowest concentrations of manganese also produce the highest concentrations of iron, which has resulted in increased complaints of rust -colored water, and over time will negatively affect the operation of valves, water meters, hydrants, and other mechanical devices susceptible to damage due to higher concentrations of iron. To properly plan for long-term solutions to reduce manganese and iron concentrations in the municipal water supply system, and to confirm the existing water supply source has adequate capacity, the City requested proposals from qualified consultants for providing professional services as outlined in the attached request for proposals. The requested professional services include analyzing the municipal water supply system source water, developing a water system model, and preparing a preliminary design report for a centralized water treatment facility to ensure