• Where water goes when it leaves your yard
• What pollutes our lakes and streams
• If the Clean Water Act is working

Urban land use and water quality

The seven-county Twin Cities Metropolitan Area is less than 3.5% of the state’s land area, but supports 54% of the state’s population and is projected to grow to 3.3 million by 2020, continuing a trend of being one of the fastest growing metro areas in the country. At the present growth rate statewide, Minnesota will double its current area of developed land in less than 40 years.

Expanding suburban areas cause an increase in impervious surfaces through the conversion of farmland and wildlife habitat and the paving of groundwater recharge areas. Stormwater runoff carries soil, fertilizers, animal waste, pesticides, salt applied to roads and walkways, oil, gasoline, antifreeze and metals from tires to lakes and streams. The EPA lists urban stormwater runoff as one of the leading sources of pollutants to Minnesota lakes and streams.

Road salt use in urban areas is also a growing concern for water quality. New research by a team of University of Minnesota researchers, provides important confirmation that road salt is the cause of chloride contamination found in Twin City lakes by documenting seasonal trends that show chloride increasing in lakes during and after the snowplowing season. The researchers also found evidence that some of the salt applied each winter remains in lake and produces chloride concentrations that have been increasing since road salt came into heavy use in the 1960s. Lowering the use of residential salt use and using alternatives can help protect lakes and streams from salt pollution.

Topics to be covered include: landscaping and lawn, winter snow removal, urban agriculture, food choices