Arizona's future was planned long ago with the construction of the Central Arizona Project (CAP) for a century of water management. We're known for long-term planning efforts, water reclamation, water conservation and groundwater reserves. But we also must look closely at every factor confronting us — climate change, a severe and lasting drought, surface water supplies, the quality and quantity of groundwater aquifers and infrastructure conditions and cost.
Monitoring our supply
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The U.S. Department of Interior is constantly monitoring the water levels in Lake Mead and the Colorado River. While the drought is a real thing, these federal administrators — along with state agencies and local leaders — are working to manage the supply and prepare for the future.
What we're doing
As the largest private water utility in Arizona, we're a proven leader in managing our water supply. Our agreements for water rights extend far into the next century and in addition, we're innovating to find new ways to manage the system.
We recently signed an agreement with the Maricopa Water District, which adds up to 5.87 billion gallons (18,000 acre-feet) of renewable water supplies to our portfolio. This addition strengthens the supply of surface and groundwater we can offer our customers. Because we carefully monitor and make repairs and updates to our systems, we ensure that water isn't wasted. We're also at the forefront of recycling and recharging the water that goes down the drain.
So, what happens if the drought triggers restrictions on Colorado River water? There's a plan.
The Colorado River Basin is divided into two sections: the Upper Basin and the Lower Basin. For purposes of discussing the drought, we'll focus on the Lower Basin, which includes parts of Arizona, California and Nevada.
In 1922, the states entered into a compact to divide the waters of the Colorado River. The Lower Basin, which Arizona is a part of, was allotted 7.5 million acre-feet of water each year in the following proportions:
- California: 4.4 million acre-feet
- Arizona: 2.8 million acre-feet
- Nevada: 300,000 acre-feet
The Colorado River is Arizona's biggest source of surface water, and the CAP canal delivers just over half (about 1.5 million acre-feet) of Arizona's allocation to central and southern Arizona.
Should water levels drop to pre-determined thresholds in Lake Mead, agriculture and aquifer recharge will be the first areas asked to reduce usage. Several triggers have to occur before municipal supplies would be impacted.
If at some point in the future municipal CAP supplies become reduced, banked water will be used to fill the shortage. The Arizona Water Banking Authority and many others, including EPCOR, have been storing water underground in our aquifers for a time of shortage. To date, more than nine million acre-feet have been stored. This banked water will be used by cities, towns and companies like EPCOR to mitigate the effects of shortage on the Colorado River.
Yes, the drought is serious. But along with our state and federal water leaders, we've been thinking about and preparing for this drought for decades. Plans are in place to guide us through this period and into the future.