Report Released on Colorado River Delta Since 2014
Minute 319 Pulse flow release from Morelos Dam, March 23, 2014
Image: Karl Flessa
On June 15, a group of four scientists released their report on a 12-year study of environmental flow impacts on the Colorado River Delta, The State of the Colorado River Delta: Effects of Environmental Water Deliveries, 2014-2025. Karl W. Flessa and Martha Gómez-Sapiens of U of A Department of Geosciences, along with Eduardo González-Sargas of Colorado State University Department of Biology and Roberto Real of The Nature Conservancy in Mexico, summarized years of monitoring observations and measurements recorded by scientists on a 40-member Binational Science Team to document the hydrological, biological, and social effects of the environmental water deliveries mandated by Minutes 319 (2013–2017) and 323 (2018–2026) of the US-Mexico Water Treaty of 1944. The authors conclude that “provision of water for the Delta environment—and funding for riparian restoration—has been a success.”
The report highlights birds and other wildlife attracted to the 1,381 acres of restored riparian vegetation, downstream rises in groundwater levels, 39 river-miles of flowing river, and community benefits, including employment, recreation, and engagement. It warns, however, that these successes are not self-sustaining. Minute 323 expires at the end of 2026, and “sustaining this binational success will require a renewed commitment of water and funding by the United States, Mexico and non-governmental organizations.” The report concludes with recommendations, based on the lessons learned during this 12-year period, for how to support the restoration sites and river channel in the future.