• The Bureau of Reclamation releases a pivotal study on water losses along the lower Colorado River.
• Key findings reveal 1.3 million-acre feet of annual water loss due to evaporation and transpiration.
• Efforts to mitigate climate change impacts and drought in the Colorado River Basin are bolstered by science and federal funding.

February 12, 2024 –– The Bureau of Reclamation last week unveiled a comprehensive analysis detailing natural water losses along the lower Colorado River, marking a significant advancement in our understanding of water management challenges in the region. The “Mainstream Evaporation and Riparian Evapotranspiration” report, published on February 8, provides an in-depth examination of water surface evaporation, soil moisture evaporation, and plant transpiration. This study is instrumental for the Bureau as it enhances its modeling efforts and guides water operations across the Colorado River Basin.

Commissioner Camille Calimlim Touton emphasized the Bureau’s commitment to science-based management, transparency, and inclusivity in addressing the complexities of water management in the Colorado River Basin and beyond.

The report’s findings reveal that approximately 1.3 million-acre feet of water are lost annually due to evaporation and transpiration along the lower Colorado River. Specifically, from Lake Mead to the Mexican border, about 860,000 acre-feet of water evaporates each year, with an additional 445,000 acre-feet lost through natural vegetation and habitat processes.

The “Mainstream Evaporation and Riparian Evapotranspiration” report is available for public access on the Reclamation website.