Water Quality

Snowpacks collect atmospheric deposition throughout the snowfall season and offer a unique opportunity to obtain a composite sample of the chemistry of most of the annual precipitation at high elevations [> 1,800 meters]. The purpose of the snowpack network is to determine annual concentrations and depositional amounts of selected nutrients and other constituents in snow resulting from atmospheric...

The Upper Yampa River Basin (UYRB) drains approximately 1,800 square miles west of the Continental Divide in northwestern Colorado. In 2019, the USGS, in cooperation with local stakeholders in the UYRB water community, initiated a study to characterize streamflow, suspended sediment, and nutrients using historic and recently acquired water-quality data from a long-term monitoring program initiated...

Every day, millions of gallons of groundwater are pumped to supply drinking water for about 140 million people, almost one-half of the Nation’s population. Learn about the quality and availability of groundwater for drinking, where and why groundwater quality is degraded, and where groundwater quality is changing.

Summaries of water-quality monitoring data are available for several major river basins in Colorado. For each basin, current data from a network of sites are compared to previously collected data and instream standards. Lowess curves are provided on plots for selected constituents where a sufficient period of record and limited censored data are available.

From 1986 to 2001, the Upper Arkansas Toxics Project focused on metal transport in streams affected by mining. Studies were conducted to quantify the physical, chemical, and biological processes affecting trace metal fate and transport.

The USGS implemented the National Water-Quality Assessment (NAWQA) Program in 1991 to support national, regional, and local information needs and decisions related to water-quality management and policy. Shaped by and coordinated with ongoing efforts of other Federal, State, and local agencies, the NAWQA Program is designed to answer: What is the condition of our Nation’s streams and ground water...

The primary objective of the project is to evaluate and update previous regression equations, developed for the USGS streamgages and continuous water-quality records, that describe the relation between specific conductance measured in the Dolores River and calculated total dissolved solids TDS. A secondary objective is to evaluate brine discharge to the river using a previously developed...

Since 1986, the USGS Hard-Rock Mining Toxic-Substances Hydrology Project has focused on metal transport in streams affected by mining. Tracer-injection studies in St. Kevin Gulch, near Leadville, Colorado, helped the USGS design methods to characterize loading from mining activities on a watershed scale. Tracer-injection studies were done in 1995, in support of the planning needs of ederal Land...

The National Ground-Water Monitoring Network (NGWMN) is a compilation of selected wells monitoring groundwater aquifers all around the nation. The NGWMN Data Portal brings groundwater data together in one place to provide users with current and reliable information for the planning, management, and development of groundwater resources.

Illinois Gulch, near Breckenridge, Colorado, is on the State of Colorado 303(d) list of impaired waters because of elevated concentrations of cadmium and zinc. Cadmium and zinc concentrations exceed chronic aquatic life standards in the upper portion of Illinois Gulch, and pH is circumneutral.

Demands for water are projected to increase in the Lower Arkansas River Basin as the population continues to grow. Strategies to meet those demands include continued operation of the Fryingpan-Arkansas Project water, enlargement of Pueblo and Turquoise Reservoirs, and various conservation measures; the overall strategy is defined in the Preferred Storage Options Plan (PSOP: see the Southeastern...

The objective of this project is to update the Ute Mountain Ute Tribe’s (UMUT) existing Groundwater Protection Plan to protect their valuable groundwater resources in Colorado, Utah, and New Mexico.