Core Principle 1: Watersheds are natural systems that we can work with

Boulder Creek (CO) Watershed Project

A local wastewater treatment plant was targeted for an expensive upgrade to reduce nitrate levels believed to be responsible for an ammonia toxicity problem in Boulder Creek. Intensive-survey monitoring of Colorado's Boulder Creek indicated a number of other factors could be contributing to the decline of the diverse fish populations from the Creek's mountain canyon to its high plains. For example, stream monitors found stream habitat so degraded that it was unsuitable for most forms of aquatic life and could be contributing to the buildup of toxic concentrations of ammonia in the water.

A physical habitat restoration program was undertaken to restore the complexity of the stream channel, stabilize the streambanks, revegetate the riparian corridor, create buffer strips to reduce agricultural and grazing runoff, and rebuild diversion and return flow structures to minimize impacts on aquatic habitat. Because of limited funding, key portions of the channel were prioritized and targeted for restoration. The BMPs, habitat restoration, and scaled-back point source nutrient control program were successful in reducing ammonia toxicity problems and revitalizing fish populations in the Creek. Boulder Creek now provides the primary corridor for an urban natural area park system.

Case Study Links:

   Cooper River Corridor Project, SC

   Occoquan Watershed, VA

   North Carolina Statewide Framework

   Boulder Creek Watershed, CO

   Merrimack River Initiative, New England

   Washington Statewide Framework