Ten More Years of Binational Efforts to Restore the Colorado River Delta: Lessons from Minute 323 (2017–2026)

Water Treaty agreements between Mexico and the United States have enabled the restoration of the riparian corridor of the Colorado River Delta—a 136 km stretch from the U.S.-Mexico border to the Gulf of California. Since 2017, Minute 323 has built upon the foundation established by Minute 319 (https://www.ibwc.gov/wp-content/uploads/2023/04/Min319_Fact_Sheet.pdf), continuing support for restoration through environmental flows and riparian habitat creation. In effect through 2026, Minute 323 represents a sustained binational commitment to ecological recovery in the Delta.

This Research Topic will present a decade of research in the Colorado River delta focused on hydrology, environmental flows, riparian restoration, vegetation recovery, wildlife dynamics, groundwater interactions, and social-ecological governance. It will also explore the potential for long-term wetland conservation and the involvement of Indigenous communities in restoration efforts. In addition to lessons learned from the Colorado River Delta, the collection will invite international contributions from other river deltas and transboundary systems in arid and semi-arid regions. We will accept Original Research papers, Opinion papers, and Reviews. Collectively, these papers will offer new insights into restoring ecosystems in highly managed and water-scarce environments.

The hydrological foundations of the restoration program will be explored through assessments of groundwater spatial-temporal dynamics along the riparian corridor, hydrological responses to environmental flows, and the use of groundwater-flow modeling to optimize restoration outcomes. Vegetation recovery will be evaluated through studies examining remotely sensed riparian metrics using Landsat and meteorological data, long-term trends in plant community composition and structure, and the effectiveness of various restoration techniques in recreating target floodplain habitats. Avian responses to restoration will be addressed through analyses of vegetation-bird relationships across successional stages, the influence of environmental flows on bird communities, and trends in avian assemblages over an extended 25-year monitoring period. Broader ecosystem and management perspectives will be included through evaluations of the hydrological ecosystem services supported by environmental flows, lessons learned from a decade of adaptive management of in-channel water releases, and efforts to establish permanent wetland conservation through legacy restoration initiatives. This Research Topic also aims to highlight Indigenous engagement, with particular attention on the role of the Cocopah Nation in restoration planning and evaluation.