Agenda - Economic Development Authority - 01/14/2021

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Economic Development Authority (EDA) 4. 4. Meeting Date: 01/14/2021 By: Bruce Westby, Engineering/Public Works Title: Consider Water Treatment Plant Site Selection Recommendation Purpose/Background: Purpose: The purpose of this case is to consider providing a Water Treatment Plant (WTP) site selection recommendation to the City Council. Background: The City of Ramsey has eight water supply wells with concentrations of manganese ranging from 0.02 milligrams per liter (mg/L) to 0.37 mg/L. The Minnesota Department of Health (MDH) has established a Health Based Value (HBV) for manganese of 0.100 mg/L. Four of Ramsey's eight water supply wells exceed the MDH HBV for manganese. MDH has recommended to the City that they develop plans to address the manganese. In addition to the potential health concerns with manganese, Ramsey's drinking water also exceeds the Secondary Standards for iron and manganese. Water with concentrations of iron and manganese above the Secondary Standard causes aesthetic problems including red and black staining of plumbing fixtures and laundry and taste complaints. The most cost effective method for removing manganese and iron from drinking water is chemical oxidation followed by sand filtration. These processes require construction of a water treatment plant. Based upon an analysis of Ramsey's 2040 water demand, the capacity of the water treatment plant should be 10 million gallons per day (MGD). The City of Ramsey currently utilizes groundwater from the Tunnel City-Wonewoc (TCW) aquifer as its exclusive source of drinking water. An evaluation of the TCW aquifer was conducted which determined that the TCW should be able to continue to produce potable water in sufficient quantities to meet present and foreseeable future demands. The Water Treatment Plant is therefore proposed to be a 10 MGD groundwater treatment plant, with planned future expansion to 20 MGD, which generally requires a minimum site area of 3.5 acres. The following four potential water treatment plant sites were identified and evaluated. • Fire Station Site - 3.2 acres undeveloped private property immediately south of Fire Station # 1. • Public Works Site - 3.5 acres City -owned undeveloped property immediately north of the new Public Works facility, which is currently under construction. • Water Shop Site - 3.5 acres City -owned property immediately west of Jasper Street where the current Public Works Utilities Shop is located. • Vacant City Property Site - 4.1 acres City -owned undeveloped property immediately east of Ramsey Boulevard and north of the BNSF rail line. The locations of the four potential WTP sites are shown in relation to each other in attached Figure 1. Each site is shown in more detail in attached Figures 4 — 7. The draft preliminary estimated project cost for constructing the WTP as proposed within the Feasibility Report is $31,890,000. Project costs include the capital cost plus contingency, administration, and engineering costs. Below is a table showing additional preliminary estimated project costs needed to prepare each of the four potential WTP sites in advance of constructing the proposed WTP on each site, which includes such costs as extending raw