Stormwater Basics

What is Stormwater?

Stormwater is the runoff from rainfall and snow melt. In undeveloped areas such as grasslands and forests, much of the rainfall and snow melt soaks into the ground. Vegetation helps to slow runoff. In urban areas, buildings and other impervious surfaces such as parking lots do not allow water to soak into the ground resulting in both increased amounts of runoff and faster flow. Along the way, runoff can pick up pollutants such as fertilizers and pesticides from yards, motor oil from leaking cars, pet waste and dirt from construction sites. This can cause downstream waterways to become polluted.

Stormwater Drainage System

The City's stormwater drainage system is separate from the sanitary sewer system (indoor sinks, toilets, etc). The sanitary sewer system drains to a wastewater treatment plant while the stormwater system drains to area streams, rivers and lakes.

What makes up the Stormwater Drainage System?
A variety of structures and land forms, both natural and artificial, are considered to be part of the stormwater drainage system. These include:

  • Box culverts
  • Detention basins
  • Ditches
  • Earth berms
  • Grass and concrete channels
  • Pipes
  • Sinkholes
  • Storm drains
  • Streams
  • Street gutters

All of these are part of the course which stormwater runoff travels on its way out of urban areas and into nearby streams, rivers and lakes.

Why is Stormwater Management Important?
Good stormwater management benefits citizens and the community by reducing potential flood hazards and protecting area waterways. Flood control and water quality best management practices are required on new developments. The City's stormwater management program also includes construction of stormwater improvement projects to address flooding and enhance water quality as well as public education, investigation of pollution and other activities.