Emerging water-quality issues within Delta, Montrose, and Mesa counties reflect changing land use practices, housing development and related pressures due to growth. Significant amounts of data have been collected by members of the Gunnison Basin Selenium Task Force as it relates to selenium related water-quality problems.
Soils within a large portion of the lower Gunnison Basin are derived from Mancos Shale which has naturally high concentrations of selenium and salts. The Loutzenhizer Arroyo sub-basin has been identified by the Bureau of Reclamation as the most significant selenium loading source in the area; consequently it exhibits the highest average selenium concentrations in the Valley.
Previous studies have also found that in areas containing soils and outcrops with high salt content, such as in the Mancos Shale on the east side of the Uncompahgre Valley, considerable salt loading occurs from canal and lateral leakage. Because Mancos Shale is a major source for selenium, it follows that canal lining and lateral piping significantly decreases selenium loading. This was proven in 1998 when the Montrose Arroyo Piping Project data demonstrated that significant selenium reduction benefits occur when salinity-control type projects (e.g. lining or piping) are implemented. The Montrose Arroyo post project monitoring showed reduced seepage, groundwater levels, and selenium and salt loads.
The U.S. Geological Survey (USGS), in cooperation with Delta County and the Shavano Soil Conservation District, developed a characterization study to provide more detailed selenium information for the lower Gunnison River Basin.
The selenium characterization study objectives are:
- To characterize selenium concentrations and loads in tributary streams of the North Fork of the Gunnison and tributaries of the Gunnison River downstream from the Smith Fork to Whitewater.
- To characterize selenium concentrations and loads in Cedar Creek and Loutzenhizer Arroyo. This report summarizes selenium data for streams in the North Fork Basin and for tributary streams of the lower Gunnison River
Below are publications associated with this project.
Trend analysis of selected water-quality data associated with salinity-control projects in the Grand Valley, in the lower Gunnison River basin, and at Meeker Dome, western Colorado
Characterization of selenium in the lower Gunnison River basin, Colorado, 1988-2000
Below are partners associated with this project.
- Overview
Emerging water-quality issues within Delta, Montrose, and Mesa counties reflect changing land use practices, housing development and related pressures due to growth. Significant amounts of data have been collected by members of the Gunnison Basin Selenium Task Force as it relates to selenium related water-quality problems.
Soils within a large portion of the lower Gunnison Basin are derived from Mancos Shale which has naturally high concentrations of selenium and salts. The Loutzenhizer Arroyo sub-basin has been identified by the Bureau of Reclamation as the most significant selenium loading source in the area; consequently it exhibits the highest average selenium concentrations in the Valley.
Previous studies have also found that in areas containing soils and outcrops with high salt content, such as in the Mancos Shale on the east side of the Uncompahgre Valley, considerable salt loading occurs from canal and lateral leakage. Because Mancos Shale is a major source for selenium, it follows that canal lining and lateral piping significantly decreases selenium loading. This was proven in 1998 when the Montrose Arroyo Piping Project data demonstrated that significant selenium reduction benefits occur when salinity-control type projects (e.g. lining or piping) are implemented. The Montrose Arroyo post project monitoring showed reduced seepage, groundwater levels, and selenium and salt loads.
The U.S. Geological Survey (USGS), in cooperation with Delta County and the Shavano Soil Conservation District, developed a characterization study to provide more detailed selenium information for the lower Gunnison River Basin.
The selenium characterization study objectives are:
- To characterize selenium concentrations and loads in tributary streams of the North Fork of the Gunnison and tributaries of the Gunnison River downstream from the Smith Fork to Whitewater.
- To characterize selenium concentrations and loads in Cedar Creek and Loutzenhizer Arroyo. This report summarizes selenium data for streams in the North Fork Basin and for tributary streams of the lower Gunnison River
- Publications
Below are publications associated with this project.
Trend analysis of selected water-quality data associated with salinity-control projects in the Grand Valley, in the lower Gunnison River basin, and at Meeker Dome, western Colorado
To decrease salt loading to the Colorado River from irrigated agriculture, salinity-control projects have been under construction since 1979 by the Bureau of Reclamation and the U.S. Department of Agriculture in the Grand Valley and since 1988 in the lower Gunnison River Basin of western Colorado. In 1980, a salinity-control project was initiated at Meeker Dome, which involved plugging three abandAuthorsD. L. ButlerCharacterization of selenium in the lower Gunnison River basin, Colorado, 1988-2000
Selenium concentrations in certain water bodies in the lower Gunnison River Basin, including the lower Gunnison River and lower Uncompahgre River, have exceeded the Colorado water-quality standard of 5 micrograms per liter for selenium. A task force was formed in 1998 that consists of various government agencies, private irrigation companies, and local residents to address the selenium concerns inAuthorsDavid L. Butler, Kenneth J. Leib - Partners
Below are partners associated with this project.