Stormwater Management

Stormwater is the water from rain or melting snow. While some water soaks into the ground or evaporates, the rest flows over rooftops, driveways, and streets into our storm sewers and local waterways. This is known as stormwater runoff.

Why Manage Stormwater?

A detailed technical cross-section of a residential home and street illustrating the 'Inflow and Infiltration' (I&I) sources in a sewer system. It shows how clear water from roof drains, foundation drains, and sump pumps can improperly enter the sanitary sewer line, contrasting it with the separate storm sewer system designed for rainwater runoff.

Managing stormwater is critical for two main reasons:

  • Preventing Floods: As we build more homes and roads, there is less ground to soak up rain. We use stormwater facilities to store runoff and release it slowly, which prevents downstream flooding.
  • Reducing Pollution: As water flows across pavement, it picks up oil, chemicals, and trash. Storing this water temporarily allows these pollutants to settle out, keeping our rivers cleaner.

How You Can Help

Interested in making a difference on your property? Explore these local resources:

Draining Pools and Spas

To protect our ponds and streams, never discharge pool or spa water into the street or storm drains. Chemicals like chlorine are deadly to fish and aquatic life.

A close-up photograph of a metal storm drain intake on a concrete curb. A large red 'prohibited' circle with a slash is superimposed over a blue hose discharging water directly into the drain, illustrating that emptying pool or spa water into the storm sewer system is not allowed.

Follow these safe draining tips:

  • Use the Sanitary Sewer: If possible, drain water into your home's sanitary sewer system per City guidelines.
  • The 7-Day Rule: If draining outside, let the water sit for 7 days without adding chemicals so the chlorine can dissipate.
  • Check the pH: Ensure the pH is between 6.5 and 8.5 before draining.
  • Drain Across Grass: Slowly drain water across at least 15 feet of grass (not concrete) to filter out remaining chemicals.

Maintaining Our Sewers

The City's Public Works team regularly cleans storm and sanitary sewers to prevent backups and keep the system running efficiently.

Questions? Call Engineering Services at 515-222-3475 or visit our Frequently Asked Questions page.

The City of West Des Moines provides these essential infrastructure services through the support of the

Stormwater Utility , which ensures the long-term maintenance and protection of our local waterways.