Floodplain and Stormwater Management

Floodplain Management

Review and evaluate building and construction activities adjacent to FEMA and community regulated floodplains. Floodplain Management staff issues Floodplain Development Permits within the county's jurisdiction. Staff coordinates floodplain activities with the Federal Emergency Management Agency (FEMA) to ensure that Arapahoe County complies with the National Flood Insurance Program (NFIP) to remain in good standing.

Master Planning

Stormwater Master Planning is completed in conjunction with:
  • Federal Emergency Management Agency (FEMA)
  • Southeast Metro Stormwater Authority (SEMSWA)
  • Urban Drainage and Flood Control District (UDFCD)

Master Planning Fees

  • Drainage Master Planning Fee ($115/Gross Acre): Arapahoe County participates in the development of regional master drainage plans. New development shall be charged a fee to cover the cost of the drainage master plan development. The county collects this fee with initial lot platting.
  • Four Square Mile Area - Storm Sewer System Recovery Cost Fee (see table below): Arapahoe County paid the cost for storm sewer installation within the Four Square Mile Area. This fee is charged with all new development to recover the cost of this expense.

Stormwater Quality

To reduce the sediment and chemical load on the State’s waters, Arapahoe County implements and enforces a Stormwater Management Program to satisfy the applicable water quality requirements of the Clean Water Act.  A program description document is available to the public for review and comment.

Public Education

  • SEMSWA: Southeast Metro Stormwater Authority (SEMSWA) provides stormwater management services for drainage and flood control facilities within its service areas in the City of Centennial and unincorporated Arapahoe County
  • SPLASH: Stormwater Permittees for Local Awareness of Stream Health (SPLASH) provides educational outreach, opportunities for public participation, and staff training to increase awareness of each person's role in protecting water quality
  • Cherry Creek Stewardship Partners: The Cherry Creek Stewardship Partners promotes open space, recreation and water quality within the Cherry Creek Watershed.