Water Quality

A Female Mallard Duck feeds in Clear Creek.

A Female Mallard Duck feeds in Clear Creek.

Because the water quality of Clear Creek is adversely impacted by numerous inactive precious metal mines and associated mine/mill waste sites throughout the watershed, the Clear Creek/Central City site was placed on the Superfund National Priority List in September 1983. More than two decades of intensive Federal, State, and local water quality monitoring makes Clear Creek perhaps one of the best-characterized watersheds in USEPA Region VIII. Numerous parameters have been monitored over the years including nutrients, metals, turbidity and flow. 

Since 1994, the Clear Creek Watershed Management Agreement Monitoring Program has collected water quality data on nutrients for 18 creek sites, eight wastewater treatment plants and nine tributary sites. This effort has been cooperatively implemented by the Upper Clear Creek Watershed Association (UCCWA) and the city of Arvada and the Standley Lake Cities of Northglenn, Thornton and Westminster. Through the years, these data have demonstrated improved water quality due to voluntary mine waste clean-ups, improvements to wastewater treatment technologies and various Superfund clean-up activities. Results of this monitoring program are published in the annual Clear Creek Watershed Agreement reports and presented to the CDPHE Water Quality Control Commission.

Water Quality Documents