City of Boulder/USGS Water Quality Monitoring
	Boulder Creek Watershed BOULDER CREEK MILLENNIUM BASELINE STUDY

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U.S. GEOLOGICAL SURVEY - CITY OF BOULDER - BASIN

Read the report from the USGS www site
View City of Boulder results
What was measured?
View a map of the sampling sites

The Boulder Creek Millennium Baseline Study, performed during the summer and fall of 2000 by the U.S. Geological Survey, the City of Boulder, and BASIN, provides an in-depth analysis of Boulder Creek water quality. This study measured several parameters not normally regulated or considered to be problematic in Boulder Creek. High-flow (June) and low-flow (October) water quality sampling of Boulder Creek from upstream of the town of Eldora to the confluence with the St. Vrain Creek was carried out to determine natural and human influences on water chemistry. The study also provides a baseline data set for the new millenium from which future water quality changes can be observed.

Stream chemistry is controlled by natural and anthropogenic (human) inputs, as well as chemical reactions that influence the fate and transport of these inputs. Detailed water quality sampling of Boulder Creek, including the main stem and major tributaries, allows us to determine the sources and sinks of chemical constituents. The relative importance of different sources varies seasonally, and therefore high- and low-flow sampling is an important step in characterizing the watershed.

A variety of measurements were made, including pH, dissolved oxygen, and major element, nutrient, metal, pesticide and pharmaceutical concentrations. See the full list of analyses.