Fall 2019 Hometown Messenger

HOW YOU CAN HELP Protecting Minnesota's water quality requires a team effort of well-designed storm drainage systems and good practices by property owners. Here's what you can do: • Do not dump anything down a street drain or catch basin. It is illegal to emit anything other than storm water into the system. • Do not blow leaves and lawn clippings onto the street. Leaves and grass soak up nutrients that can cause algae. • Pick up after your dog. Pet feces carry nutrients harmful to the ecosystem. • Consider adopting a storm drain in your neighborhood and keep it free from leaves and debris. • Use appropriate amount of salt. Most driveways require less than

Graphic courtesy of City of Wilmington, NC Storm water Services

How storm water is managed can look different based on density and age of development, Templin explained. In rural areas, ditches and road culverts often help water flow to wetlands and streams on its way to the river. In higher density areas, you'll see more catch basins and underground storm pipes since there's less surface area to work with. Regardless of whether your street has curb and gutter, there's a designed drainage network that must be maintained to

handle the storm water runoff and mitigate issues, Templin said. A component of storm water management is volume reduction, which assists both with flood control and water quality. For example, infiltration basins are dry depressions designed to fill up during storm events but dry out within a few days. These pervious basins mitigate the flow of

a cup of salt to work effectively. Sweep up excess salt and sand.

Another unique factor is the quantity of water that flows from adjacent cities and townships. Surface water from Lake O'Dowd and Prior Lake flow through Shakopee via outlet channels, which

uses a system of culverts, pipes, wetlands and ditches to transport water to the Minnesota River. There are cost-share agreements with neighboring communities for the construction and maintenance of these systems. The city is responsible for administering federal and state storm water management requirements, most commonly by reviewing proposed development. The Public Works Department also inspects and maintains the city's storm

water while also filtering out pollutants from reaching our lakes and rivers. "In Minnesota, we have a lot of water resources. Keeping them clean and usable for different purposes is everyone's responsibility," Templin said. TOPOGRAPHY & SOIL Shakopee has several unique challenges due to its topography and soil conditions. The bluffs create

"We have a lot of water resources. Keeping them clean and usable for different purposes is everyone's responsibility." Kirby Templin Water Resources- Environmental Engineer

FLOODING FLASH (LOCALIZED) VS. LONG-TERM (REGIONAL)

After a large storm event, you may notice standing water in your neighborhood.

Smaller systems often see the first impact of excessive precipitation.

However, large-scale flooding events, like those that occur along the Minnesota River, can take days, weeks or even months to appear as it takes longer for water to flow through the system. Storm drainage systems are designed to manage both types of flooding events. Engineers use projections based on 2-, 10- and 100-year floods to design infrastructure that can withstand a variety of flow conditions.

drainage system for pond cleanouts, erosion or other maintenance issues. Street sweeping minimizes leaves, sand and salt residue from running into the storm system. To learn more about the city's storm drainage system, visit the city website at www.ShakopeeMN.gov/publicworks.

large elevation changes within a short distance. The city also has a variety of soil types, ranging from sandy, which allow high infiltration and less runoff in pervious areas, to clay, which does not infiltrate well. Other parts of the city have shallow bedrock, which requires blasting to create ponds or below-ground utilities.

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