How Does Arizona Get Water From the Colorado River?
Arizona, being a desert state, needs a diverse portfolio of water supply and management solutions to thrive. Its largest renewable water supply, the Colorado River, allocates 2.8 million acre-feet to the state for annual use.
Followed closely behind groundwater, the Colorado River makes up a significant portion of Arizona’s water supply. If you haven’t been following Arizona water news, here’s a quick breakdown of how Arizona gets its water from the “Grand River” and what you need to know about the state’s water conservation efforts.
Central Arizona Project
The Central Arizona Project (CAP) is a reliable 336-mile system that brings Colorado River water to central and southern Arizona, serving over 80 percent of the state’s population. It waters much of the state’s agricultural land and is the largest supplier to tribes. The CAP system is essential for the 60+ water users it supplies. These users fall under three main groups: municipal and industrial, agricultural, and Native American tribes.
Construction of the CAP system began in 1973 and was completed 20 years later under the price tag of over $4 billion. This engineering marvel pumps nearly 500 billion gallons of water uphill. Coming in through the western Arizona border, Colorado River water enters the CAP canal from Mark Wilmer Pumping Plant via Lake Havasu.
Lifting the river water nearly 3,000 feet from Lake Havasu to the terminus south of Tucson, the CAP is Arizona’s largest single power user. It also takes about 2.5 million megawatt-hours (MWh) to deliver 1.4 million acre-feet of CAP water annually.
The CAP system includes 14 pumping plants in total, a hydroelectric pump/generating plant at New Waddell Dam, a storage reservoir at Lake Pleasant, 39 radial gate structures to control water flow, and 50 turnout units that deliver the water. There are four tunnels that move the water through mountainous terrain.
Arizona’s economy is undoubtedly strengthened by the use of the CAP system. It provides the most reliable, and renewable, water supply to the state via the Colorado River. This sophisticated system grants residents a higher quality of life that would be difficult to achieve without it.
CAP Priority System
Water access to the Colorado River is linked to a priority system. CAP’s share to the river’s water is considered “junior” in comparison to other states in the Lower Basin (California and Nevada). A junior share means that supply takes its biggest cut in times of shortage.
The CAP system reserves Arizona the right to divert water that equal and higher priority users in the state aren’t using, which is a useful strategy in conservation and allocation efforts.
Water Conservation in Arizona and Why It Matters
With its desert climate, Arizona takes several steps to mitigate the effects of drought. Thanks to things like the CAP Priority System, higher priority users are insulated from early supply reductions. While agricultural users could see a reduction in their water supply, any kind of water shortage should not have any immediate impact on municipal and tribal water supplies.
Services like The Arizona Department of Water Resources (ADWR) Conservation Program and others offer integrated approaches to water conservation in the state. Through these programs, Arizonans learn how to practice a low water-use lifestyle to ensure their communities have a sustainable water supply. By having residents effectively reduce their water use, they will benefit from reductions in energy costs, thus meeting immediate and future water needs and preserving the beautiful desert landscape.
Discover More Arizona Water News
Arizona state residents can take part in learning more about how they can manage their water. Find the latest news you need to know about Arizona’s water conservation efforts with services that provide Arizona water news.
