Artificial Recharge and Storage Alternatives

Water storage is a crucial feature of Colorado’s water supply systems. Adequate water storage is necessary to meet peak summer water demands and for extended drought periods. The need for additional water storage capacity in Colorado was highlighted by the 2000-2004 drought period when many surface reservoirs were nearly empty.

Surface-water reservoirs are the mainstay for water storage in Colorado – but there is another option that can augment our current water storage capabilities. That alternative is to store water underground in aquifers.

The CGS has completed an analysis of storing water underground through “artificial recharge.” Artificial recharge is defined as any engineered system designed to introduce water to, and store water in, underlying aquifers. The study, titled EG-13 Artificial Recharge of Ground Water in Colorado: A Statewide Analysis, explores various geological and technical aspects of artificial recharge in Colorado.

cover, EG-13 Artificial Recharge of Ground Water in Colorado: A Statewide Analysis

The CGS has produced two reports on the potential for aquifer recharge within two small alluvial aquifers: The Upper Black Squirrel Basin in El Paso County and the Lost Creek Basin in Adams, Arapahoe, and Weld Counties. Both projects were made possible by the support of the Metro and South Platte Roundtables and the Lost Creek Ground Water Management District and funding provided through a Water Supply Reserve Account (SB06-179) grant from the Colorado Water Conservation Board. Additional project funding was provided by the Colorado Geological Survey from funding from the Colorado Department of Natural Resources Severance Tax Operational Fund. Severance taxes are derived from the production of gas, oil, coal, and minerals.

Upper Black Squirrel Basin

The OF-08-04 Upper Black Squirrel Creek Basin Evaluation report integrates new field data with information from previous studies and cooperating partners to refine knowledge of the alluvial aquifer system hydrogeology within the Upper Black Squirrel Creek basin to help identify potential sites for aquifer recharge and storage implementation.

The study area encompasses the entire Upper Black Squirrel Creek drainage basin and coincides with the designated ground water basin boundary. This basin encompasses an area of approximately 350 square miles and is entirely within east-central El Paso County, Colorado. All the streams in the basin are ephemeral, have dry sandy streambeds, and flow only in direct response to thunderstorms, spring snowmelt, or prolonged periods of rainfall. Consequently, these streams are not a reliable water source. Ground water from the alluvial aquifer has been the dominant water source since the late 1800’s.

Download: OF-08-04 Upper Black Squirrel Creek Basin Evaluation, including 7 Figures, 3 Tables, 19 Plates, and Appendices. (PDF file)

Lost Creek Basin

The CGS report OF-11-05 Lost Creek Basin Aquifer Recharge and Storage Study report presents the results of an assessment of the potential for groundwater recharge and storage in the alluvial aquifer within the Lost Creek Designated Ground Water Basin. Water users in the Lost Creek basin are heavily reliant on groundwater from the alluvial aquifer for agricultural, domestic, and commercial uses. The primary goal of this study was to quantify the existing groundwater reservoir and additional available storage capacity in the Lost Creek alluvial aquifer and identify potential sites for aquifer recharge and storage implementation. The project involved collecting and analyzing data to evaluate the recharge potential, storage capacity, and ambient water quality in the study area. The study area encompasses the Lost Creek drainage basin and coincides with the Lost Creek Designated Ground Water Basin boundary. The Lost Creek basin encompasses an area of approximately 433 square miles and lies within southeastern Weld County, central Adams County, and the northern portion of Arapahoe County.

Download: OF-11-05 Lost Creek Basin Aquifer Recharge and Storage Study, including 31 Figures, 4 Tables, Appendices, and GIS data. (ZIP file)