The construction of El Vado dam on the Rio Chama in 1935 dramatically changed the natural flow of the river, reducing spring runoff and summer scouring floods in favor of providing a constant water supply to downstream users. The San Juan-Chama Project, a trans-basin water diversion built as part of the Colorado River Compact, also significantly increased water flow in the river, a unique situation in the state of New Mexico. This increase in management of the river for human benefit has permanently altered the natural hydrograph of the river and the ecology and geomorphology of the system that depends on it.
The Rio Chama Flow Project (Flow Project) has worked since 2010 to explore the possibility of adaptively managing the flow out of El Vado dam to maximize river and riparian health while still meeting current user needs for agriculture, drinking water, recreation, and hydropower. The Flow Project currently encompasses three distinct groups coordinated by Rio Grande Restoration: the science advisory team, Rio Grande basin water and land management agencies, and stakeholder groups. By allowing all three groups a space at the table, collaborative decisions can be made about what the needs of the river are, how they match up with broader community opinions, and how water can be physically released to meet both needs concurrently.
The Flow Project has focused primarily on stakeholder engagement and technical studies led by a science advisory team. Technical efforts have included organizing and conducting baseline studies and models to propose basic flow hypotheses, and initial monitoring of several experimental releases to test them. Given very limited funding, the Flow Project has been quite successful in gathering the appropriate stakeholders and negotiating ongoing releases for the benefit of the river channel and aquatic species that depend on it.
Because so much of the technical assessment efforts have been pro bono, the science to date has also been intermittent and opportunistic. The technical team and water managers associated with the Flow Project collectively can claim detailed knowledge of the system’s many complexities, but the information is often siloed both by agency and individual expert. The Flow Project lacks consistent documentation of past efforts and successes, and runs the risk of losing valuable information should any individual leave. As the Flow Project moves toward its 10th anniversary, this paper aims to provide some guidance and clarity on the way forward for environmental flow management on the Rio Chama. This work first provides a consolidated overview of the current management conditions of the river, and the changes that have been made to date in altering flow. This work also identifies the Flow Project’s strengths and potential challenges, as the technical team gets closer to defined flow recommendations. Drawing on the results from a series of structured interviews, it will highlight the opportunities and constraints currently seen by water managers, answering the dual questions of where we came from and where we go from here.
El Vado dam, Rio Chama, San Juan-Chama Project, a trans-basin water diversion, Colorado River Compact, ecology, geomorphology Rio Grande Restoration
Bean, Anjali. "Opportunities to Enhance Environmental Flows on the Rio Chama." (2018). https://digitalrepository.unm.edu/wr_sp/160