BLM works with partners to acquire Shaw Reservoir water rights and storage space

Story by Maribeth Pecotte, Public Affairs Specialist. Photos by Roy Smith, Water Rights Specialist.

Set in a beautiful mountain valley along the South Fork of the Rio Grande, the 48 surface-acre Shaw Reservoir is popular for fishing, boating, and other recreation. In a landmark deal facilitated by The Conservation Fund (TCF), the Bureau of Land Management (BLM) and San Luis Valley Water Conservancy District (District) have acquired the Shaw Reservoir water rights, dam, feeder ditch, outlets, and historic easements on the Rio Grande National Forest where the reservoir sits.

The acquired water and storage space will be used to increase and maintain wetlands at BLM’s Blanca Wetlands Area located many miles downstream. The water and storage space will be used to improve riparian zones, fisheries, and other wildlife habitats along the Rio Grande when stored water is released during low flow periods. The assets will also be used to improve recreational opportunities at the reservoir, along the Rio Grande, and at Blanca Wetlands Area.

Known as “The Land of Cool Sunshine,” the high-elevation San Luis Valley covers 8,000 square miles and supports extensive agriculture. However, irrigation and other pumping throughout the valley bottom have lowered the water table, reduced wetland acreage, and reduced Rio Grande flows. The District runs a water augmentation program in the valley, storing water in area reservoirs for release into the Rio Grande. The water is released to offset depletions to the Rio Grande that are caused by the operation of wells. The District currently spends substantial sums to store augmentation water at multiple locations and it wanted to purchase its own storage facility to reduce operating costs.

The proposed acquisition was discussed with Colorado Parks and Wildlife (CPW), who suggested maintaining a more stable pool of water at Shaw Reservoir compared to past irrigation practices, in order to better support fish populations and angling. To facilitate the acquisition and provide these benefits, CPW entered into 25-year exchange agreements with BLM and the District to store their waters at Beaver Park Reservoir, operated by CPW, allowing a conservation pool to be maintained at Shaw Reservoir. The storage agreements allow the acquisition project to fulfill BLM’s, CPW’s, and the District’s objectives simultaneously. 

The BLM’s objective for this project is to restore historic wetland basins at the Blanca Wetlands Area that have dried up due to the lowered water table. In 2016, the San Luis Valley Field Office was awarded $6.4 million from the Land and Water Conservation Fund (LWCF) for that purpose. Acquiring the water rights and storage allows the BLM to capture water and release it to the wetlands by way of the Rio Grande at times of year when it most benefits wetlands and migratory birds. BLM will typically release water from storage in February/March and July, wetting the basins to prepare them for spring and fall bird migration.

The Shaw Reservoir acquisition is the second such purchase made with the LWCF funding. In 2019, BLM Colorado purchased Treasure Pass Ditch, which collects snowmelt at the Continental Divide on the west side of Wolf Creek Pass and diverts it to the Rio Grande headwaters. The storage agreement with CPW also allows BLM to store water diverted by Treasure Pass Ditch for release at dates that benefit wetlands. 

Together, the two acquisitions will enable the creation and maintenance of an additional 114 wetland acres at Blanca Wetlands Area, while improving the area’s hunting and other recreational opportunities. BLM Colorado is reviewing other properties for a final acquisition that would utilize the remaining LWCF funding.

The entire project was facilitated by TCF. TCF arranged to have the District purchase all assets of the historic Shaw Reservoir Company, and then convey the water rights and 49% of the storage space in the reservoir to BLM.