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Learn About Stormwater

What is Stormwater?

Stormwater is rain, melting snow, and ice that flows across the surface.  We usually think of stormwater management in urban settings, but it is important in all developments.

Why is stormwater important?

In rural settings, stormwater is often managed in open ditches.  In urban settings, stormwater is collected in catch basins (storm drains), which are connected to storm sewers.  These storm sewers are underground pipes that usually lead to the closest waterbody.

Is stormwater treated?

Most stormwater is not “treated” before it is released to the nearest water body.  This is very different from sanitary sewers, which flow through closed systems to a water treatment plant.  For this reason, we must be very mindful of what can enter our stormwater systems.

How does stormwater get polluted?

Stormwater pollution is widespread, and much of it is preventable.  Stormwater acts like a broom that pushes pollution left on surfaces toward storm drains, ditches, and streams.  Cleaning up before a storm can prevent the stormwater from picking up pollutants along the way.

What kinds of pollution are we talking about?

There are many common pollutants that stormwater can become contaminated with:

  • Sediment – Very common, contains phosphorus, which can cause algae blooms and is detrimental to aquatic habitats.
  • Automotive – our transportation has the potential to leak oils and other fluids, as well as depositing particles from tires, brakes, and exhaust.
  • Industrial – industries are regulated, but accidents can happen.
  • Salt – Rock salt on our roadways makes them safer in winter time but can cause elevated salt levels in waterbodies, even after winter is over.
  • Litter – Most commonly, single-use items such as shopping bags, food and beverage containers, and cigarettes.

What can we do to keep stormwater clean?

There are many ways to prevent stormwater pollution.  It takes a community effort to keep our waters clean.  Check out our resources page for more information.