All Municipal Separate Storm Sewer Systems (MS4s) in the watershed have adopted stormwater regulations that set water quality requirements, consistent with Regulation 72 ,for construction and post-construction of new development and redevelopment projects within their jurisdictions. Further information on each MS4’s program can be found in their annual reports, due to the Division on March 10 (Phase II MS4s) and April 1 (Phase I MS4s).

Find Out More About MS4s

• link Aurora Water MS4 education page
• link Arapahoe County Splash
  (Arapahoe County, City of Cherry Hills Village, City of Centennial, Cherry Creek State Parks, City of Sheridan, Greenwood Village)
• link One thing is Clear
  (Douglas County, Town of Castle Rock, Town of Parker, City of Lone Tree, Highlands Ranch Metro District, Castle Pines Metro District, Castle Pines North Metro District, Stonegate and Lincoln Park Metro Districts)
• link H2O Jo Informational Video