Agenda - Environmental Policy Board - 03/16/2020

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Infiltration and groundwater quality protection can be in conflict with each other. State policies direct municipalities to have source water protection strategies that discourage infiltration of stormwater to protect groundwater from contamination. Pollutants such as nitrates, chlorides, pathogens, and heavy metals are not adequately filtered by the sandy soils of the Anoka Sand Plain. Ultimately, policy makers have to choose between having adequate ground water supplies that require treatment before consumption, or groundwater supplies that don't require treatment but are in a state of decline. Impaired waters are lakes and streams that are officially listed as failing to meet water quality standards. They are prevalent locally and statewide. In Anoka County, there are 16 impaired lakes and 13 impaired streams (not including mercury and fish consumption impairments). Efforts that successfully improve water quality to meet state standards can result in delisting. Watershed -level management is a longstanding concept in Minnesota but is now being applied at a larger scale. The new statewide approach of "One Watershed, One Plan" seeks to coordinate management across multiple organizations within the same larger watershed (e.g. the Rum River watershed). In the seven -county metro area, SWCDs can take a leadership role to facilitate collaboration across county and water management entity boundaries. Nitrogen pollution in surface water, most prevalently in the form of nitrate, has been show in a number of studies to be the primary cause of the dead zone in the Gulf of Mexico. Additionally, when it accumulates in drinking water beyond 10mg/L it causes health problems in vulnerable individuals. Current nitrate concentrations in Anoka County drinking water wells appear to be well below the 10 mg/L threshold. Chloride pollution in surface water and groundwater has been slowly trending upward. Chloride is highly soluble and accumulates over time until concentrations exceed healthy levels for consumption or irrigation. In urban environments, chloride is primarily from road salt application. Due to the delivery mechanism and timing of application when soils are frozen, much of this chloride finds its way through the stormwater conveyance system into the Mississippi River and ultimately the Gulf of Mexico, where it contributes to the Dead Zone. In rural environments, water softeners cycle 4