"...is that area of land, a bounded hydrologic system, within which all living things are inextricably linked by their common water course and where, as humans settled, simple logic demanded that they become part of a community". John Wesley Powell
Boulder Creek-St. Vrain Creek Watershed
The St. Vrain Creek watershed includes two major subwatersheds:
- Boulder Creek
- St. Vrain Creek
Boulder Creek and its tributaries flow through the southern portion of Boulder County and St. Vrain Creek and its tributaries flow through the northern portion of Boulder County (See Map). The two streams join to form the main stem of St. Vrain Creek, just east of the Boulder-Weld County line, and ultimately flow into the South Platte River near Greeley, Colorado.
Major tributaries to Boulder Creek include
- Coal Creek (and its tributary, Rock Creek)
- South Boulder Creek
- Fourmile Creek
Major tributaries to St. Vrain Creek include
Urbanized areas in the watershed include
There are also several smaller non urbanized communities such as Eldora, Nederland, and Lyons within the watershed.
Water quality in the watershed is influenced by natural geology, land use including impervious surfaces, stream channel characteristics, discharges of treated wastewater, urban and agricultural runoff, and other conditions present in land areas draining to the major streams and their tributaries. Because the watershed crosses multiple jurisdictional boundaries, a coordinated watershed planning approach among local governments is an effective strategy to improving water quality and protecting streams and lakes.
In 2013, the City of Boulder, working closely with the Keep it Clean Partnership, received a grant from the Colorado Department of Public Health and Environment to develop a watershed management plan for the Boulder Creek watershed and to develop a coordinated monitoring plan for the overall St. Vrain watershed. In 2014, grant funding was increased to allow for the entire St. Vrain watershed to be include in the plan. This planning effort focuses on water quality and particularly on actions that can be taken to decrease non-point source pollution. The watershed plan is a framework-level document that documents key characteristics of the overall watershed, assesses existing water quality, and makes recommendations regarding actions that can be taken to improve water quality in the future.
Water quality in the Boulder Creek watershed is good overall; however, elevated levels of E. coli, which is a fecal indicator bacteria (FIB), are present in portions of both the urban and agricultural areas of the watershed. FIB such as E. coli are used to indicate the potential presence of pathogens (disease-causing organisms) associated with fecal contamination. FIB can originate from human sources, pets, and wildlife, as well as persist in the environment outside of a living host. Identifying sources of FIB is an important first step in selecting control measures. Human sources of fecal waste are the highest priority to identify and control, whereas there may be limited ability to control wildlife and environmental sources. Over 80,000 dogs live in Boulder County, with an even larger population frequenting the Boulder County open space and trail system; therefore, proper disposal of pet waste is also a key opportunity to reduce FIB loading to streams. Wastewater treatment plants in the watershed have permits and discharge permit limits for E. coli, which are much lower than instream recreational use standards.
Although stream standards for total phosphorus and total nitrogen are not yet applicable to streams in the watershed, future compliance with interim values adopted by the Colorado Water Quality Control Commission in 2012 is expected to be a significant challenge. For this reason, watershed planning will also recommend practices to help reduce nutrient loading from non-point sources. It should be noted that the Front Range activities such as coal-fired power plants, automobiles and agricultural activities release contaminants such as nitrate which can cause atmosphere deposition in the upper watershed.
How Can I Help?
- Pick up after your dog—on-leash, off-leash and in your yard. See Scoop the Poop for more.
- Properly maintain your septic system. See Septic Smart for more.
- Secure garbage cans and pet food to reduce food sources for urban wildlife such as raccoons.
- Properly apply fertilizer—only apply what your lawn really needs. See Lawn & Garden Tips for more.
- Keep irrigation on the lawn and out of the gutter. See Lawn & Garden Tips for more.
- E. coli in St. Vrain/Boulder Watershed
- Nutrients in St. Vrain/Boulder Watershed
- St. Vrain/Boulder Watershed Plan September 2015
- Appendices to Watershed Plan September 2015
- St. Vrain/Boulder Watershed Monitoring Plan September 2015
- 2014 St. Vrain/Boulder Watershed Annual Monitoring Report
- 2015 St. Vrain/Boulder Watershed Annual Monitoring Report
- 2016 Left Hand Creek Water Quality Report
- Impaired Waterways
- What is a Total Daily Maximum Load (TMDL)?
- Boulder Creek E. coli TMDL 2011
- South Boulder Creek Ph, Zinc and Copper TMDLs 2009
- Gamble Gulch Cadmium and Zinc TMDLs 2010
- Boulder Creek, South Boulder Creek to Coal Creek, Ammonia TMDL 2003
- Boulder Creek, Coal Creek to St. Vrain Creek, Ammonia TMDL 2003
- St. Vrain Creek, Hygiene Road to South Platte River, Ammonia TMDL 2003
- Little James Creek pH Cadmium, Iron, Manganese, and Zinc TMDLs 2002
- Left Hand Creek, Hwy 72 to James Creek, Cadmium, Copper, Lead, Zinc and pH TMDLs 2015
- James Creek, Little James Creek , Cadmium, Copper, Lead, Zinc, and pH TMDLs 2015
- Left Hand Creek, James Creek to Hwy 36, Copper TMDL 2015
- How’s my Waterway EPA website
- USGS State of the Boulder Creek Watershed
- Boulder County Comprehensive Creek Planning Initiative
- Boulder County 2012 Parks and Open Space Water Policy
- USDA NRCS Hydrologic Analyses of Post-Wildfire Conditions
- Nitrogen, Agriculture and Rocky Mountain National Park
- National Atmospheric Deposition Program
- Colorado Regulation 85 Nutrient Data Gap Analysis Report
- Colorado Regulation 85 Nutrient Data Gap Analysis Presentation
- City of Boulder Regulation 85 Discharge Assessment Data Report
- E. coli Workgroup White Paper 2009
- Pathogens in Urban Stormwater Systems
- Colorado E. coli Toolbox 2016
- The Ditch Project – 150 years