The CAP has been actively participating in water supply augmentation and conservation projects. Water conservation programs, such as the Brock Reservoir project, are contributing to improve water supply reliability by making the process of real time deliveries to users downstream of Imperial Dam more efficient. Other initiatives such as the Basin Study and Desalination projects contemplate projects that eventually could provide additional water supplies to Lower Basin users, including CAP.

Basin Study

The Colorado River Basin Water Supply and Demand Study is a collaborative study between the Seven Colorado River Basin States (Arizona, Nevada, California, New Mexico, Wyoming, Utah, and Colorado) and the Bureau of Reclamation. The study is intended to quantify and address future demand and supply imbalances in the Colorado River Basin through a scenario planning approach. In addition, the study evaluates system reliability and outlines potential options and strategies that can be utilized to meet these imbalances.

Brock Reservoir

Each year, about 6 million acre-feet of Colorado River water is regulated at Imperial Diversion Dam, just north of Yuma, Arizona, for irrigation and other uses in California, Arizona and Mexico. That water must be released from storage in Lake Mead, nearly 300 miles to the north. It takes about five days for water released from Lake Mead to reach Imperial Dam. By the time the water arrives at Imperial Dam, the water users that scheduled the water delivery may be unable to take it due to factors that limit those water users' ability to utilize the water (such as the occurrence of precipitation during those 5 days for agricultural water users). In order to address this requested water that otherwise would be lost to the system, the United States Bureau of Reclamation (USBR) coordinated the construction of Brock Reservoir. Brock Reservoir is a man-made reservoir, composed of two basins, with a total combined capacity of 7,945 AF. This project was approved and constructed during the period of 2008-2010, with a total cost of $172 million, and was partially financed by CAP, Southern Nevada Water Authority (SNWA), and Metropolitan Water District (MWD) of Southern California; each with an equal contribution of $28.6 million. According to USBR, it is estimated that the project could save 70,000 AF per year. As part of their contribution, SNWA can use 400,000 AF of Intentionally Created Surplus (ICS) water credits over 20 years, while CAP and MWD can each use 100,000 AF of ICS water credits starting in 2016.

Cienega de Santa Clara

The Ciénega de Santa Clara (CSC) is the largest wetland on the Mexican portion of the Colorado River Delta. The origins of the Ciénega date back to 1977 with the beginning of the disposal of brackish groundwater from the Wellton-Mohawk Irrigation and Drainage District. Given to its high salt content, this water is not considered as a part of water deliveries to Mexico as established in the 1944 International Water Treaty. CAP recognizes that the Cienega de Santa Clara provide significant environmental values, and has been supportive of monitoring and data gathering efforts. CAP, SNWA, and MWD financed a recently completed two year monitoring program. Currently, there are ongoing activities related with obtaining additional information from the CSC in terms of evaluating potential management options, and evaluating the potential of implementing a more comprehensive understating of water mass balance for the wetland.

Metropolitan Water District of Southern California (MWD) Regional Recycled Water Program

The Arizona Department of Water Resources (ADWR) and Central Arizona Water Conservation District have signed a letter of intent to pursue collaboration with the Metropolitan Water Conservation District (MWD) of Southern California’s Regional Recycled Water Project (RRWP). This project would purify and reuse wastewater and potentially offset the use of imported supplies such as Colorado River water. The collaboration is an extension of cooperative efforts, including with the Southern Nevada Water Authority to explore and develop new projects and infrastructure to potentially augment the Colorado River. The RRWP is a unique opportunity to potentially improve the reliability of Colorado River water supplies to benefit Arizona, California and Nevada water users and create new flexibility and resiliency in the Colorado River system.


During the last 10 years, CAP has been engaged in different innovative projects that target decreasing the risk of water shortage conditions in the Lower Colorado River Basin. Different studies have pointed out that the removal of tamarisk, a non-native species, could considerable decrease water losses in the main stem of the Colorado River. However, there is still an unclear methodology for the estimation of potential water savings by the implementation of tamarisk removal and the restoration of native species. CAP, in collaboration with other partners, is currently developing a research concept to better understand specific water savings from implementing a tamarisk removal and restoration project.

Weather Modification

Weather Modification activities support cloud seeding projects in the Upper Colorado River Basin that aim at generating greater runoff volumes in the Colorado River. Weather Modification is a jointly funded endeavor between CAP, SNWA, and California's six agency committee and targets cloud seeding operations in the states of Wyoming, Colorado, and Utah. These and many other weather modification activities are coordinated with the North American Weather Modification Council (NAWMC).

Yuma Desalination Plant (YDP)

As a part of Minute 242 and its intention to define a "permanent and definitive solution" to the international salinity problem of water deliveries to Mexico, the USBR was authorized to construct and operate the Yuma Desalting Plant (YDP) to treat Wellton Mohawk Irrigation and Drainage District's (WMIDD) drainage water, and deliver the treated water as a part of the U.S. treaty obligations for water deliveries to Mexico. Due to different factors, YDP has remained largely inactive since construction was completed in 1992. Current drought conditions and increased water uses exacerbate the vulnerability of Lower Basin users to Colorado River's water shortages.  This has motivated water users to evaluate the operation of YDP (2010 Pilot Operation Run and Evaluation of Technological Advancements and Alternative Feed Water Supplies for Operation of Yuma Desalting Plant- CRADA Report) as well as consider alternatives to operating the plant (Yuma Desalting Plant (YDP) Long Term Operational Alternatives).