Southeast Metro Stormwater Authority

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Providing floodplain and stormwater management services since 2006.

SEMSWA is a local government (Drainage Authority) that provides stormwater management services within the Service Area including the City of Centennial and Unincorporated Arapahoe County west of Coal Creek

Latest News & Alerts

Explore our latest work and activities

Explore Our Interactive Maps

Learn more about stormwater in our urban environment.

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Customer Service

SEMSWA strives to provide excellent service to all customers in our Service Area.

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Development Projects

We provide stormwater management services for land and community development in Centennial & Arapahoe County.

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Education & Outreach

Learn more about stormwater and our efforts to connect with our Community.

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SEMSWA Projects

Our Maintenance and Capital Improvement Programs conduct routine and project based work throughout our entire Service Area.

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Water Quality

SEMSWA is an MS4 permit holder and responsible for monitoring and regulating activities that contribute to stormwater pollution.

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Floods and Floodplains

SEMSWA has a comprehensive Floodplain Management Program.

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