ERMUSR 4-11-2023 Special Meeting

Home Browse Search

Elk River Municipal Utilities Wellhead Protection Plan April 11, 2023 Background As a public water provider, the Elk River Municipal Utilities (ERMU) is required by the Minnesota Rules, parts 4720.5100 to 4720.5590 as administered by the Minnesota Department of Health (MDH) to develop a plan to 1) understand where their source water comes from and how vulnerable it may be to contamination (Part 1), and 2) identify potential sources of contamination based on geologic vulnerability and management strategies addressing potential contaminants (Part 2). The plan is referred to as Wellhead Protection (WHP). The wellhead rules also require a public water supplier to amend current WHP plans every ten years. This is the second amendment to the ERMU WHP plan. A WHP team formed in January of 2022 to assist in the amendment of Part 2 of the ERMU WHP plan has completed its task. Local governmental units (LGU) and the public have been given the opportunity to review the draft Elk River Municipal Utilities WHP plan. A brief scope of the WHP plan The ERMU Drinking Water Supply Management Area (DWSMA) covers approximately 17,268 acres (-27 square miles) with about 15,360 acres classified as low vulnerability and 1,908 acres classified as moderately vulnerable (see DWSMA Map attachment). 1. Groundwater vulnerability • Nearly 90 percent of the DWSMA is classified as low vulnerability. In the low vulnerable area geologic materials composed of clay -rich glacial sediments and the Eau Claire formation provide protection to the Mount Simon -Hinckley aquifer. Within the low vulnerability areas, the primary threats to the city's aquifer are other wells that reach or penetrate it. Where the DWSMA vulnerability is classified as moderate, pathways exist where water and contaminants may travel from the land surface to the aquifer within a time span of years to decades. Aquifers underlying moderate vulnerability areas are susceptible to several types of contaminant threats, including chemical/petroleum storage tanks and unused or unsealed wells which can provide conduits for contaminants to quickly reach the city's aquifer. 2. Components of the Plan • See Forward (attached) • Primary Issues, Opportunities and Problems in the DWSMA: - The City of Elk River population will increase over the next ten years resulting in increased demand for potable water. - ERMU will likely need additional wells or replace primary wells to address increased water demand. - There are over 1,000 wells located within the DWSMA with about 365 of them using the same aquifer as ERMU public water supply wells. - There may be unused or abandoned wells located in the DWSMA that may pose a threat to the aquifer. - The Mt. Simon -Hinckley aquifer is the sole -source of drinking water for Elk River and other entities in the region. - Increased usage of the Mt. Simon -Hinckley aquifer to meet regional water demand is a concern. - ERMU could partner with state agencies and other public/private users of the Mt. Simon - Hinckley aquifer to develop a regional, sustainable use aquifer plan. 3