Monitoring The Water Quality of the Nation's Large Rivers Colorado River NASQAN Program

Since 1995, the National Stream Quality Accounting Network (NASQAN) of the U. S. Geological Survey (USGS) has focused on monitoring the water quality of the Nation's largest rivers including the Colorado, Columbia, Mississippi, and Rio Grande. The NASQAN program in the Colorado River Basin consists of eight stations that span seven basin States including Colorado, Wyoming, Utah, New Mexico, Arizona, Nevada, and California. Data collected from these stations are used to quantify the transport of chemical constituents and evaluate trends in water quality of the river. Currently, the NASQAN program in the Colorado River Basin is providing necessary data and information required by resource managers of the river who are responsible for meeting longstanding legal agreements that regulate the flow and quality of the river water.