I recently attended a three hour conference about the state of water resources in Arizona and wanted to share some notes provided by three top experts in the field. This will be one of a short series of reports about Arizona water–our most precious resource. Let’s get into my Arizona water resources report for 2023.
One of the most startling things I learned is that overall, our water usage from 1957 to 2019 (as measured in million acre feet or MAF) has only changed 3% and the use has actually gone down. In 1957, we used 7.1MAF and in 2019 we used 6.9MAF. The most recent data collected up to 2019 indicates that our water comes from four main sources:
- Groundwater: 41%
- Colorado River: 36%
- Rivers: 18%
- Reclaimed water: 5%
Total water usage by sector is:
- Municipal: 22%
- Agricultural: 72%
- Industrial: 6%
Important Lakes
Two critical lakes for Arizonans are Lake Powell and Lake Mead. Currently, both lakes are operating at less than 30% of their capacity, though due to rains this past season, both lakes have increased in capacity and will increase further as the final snow melts. Lake Powell, which was operating at 23% capacity should increase to 38% this year. Lake Mead will increase to 40% capacity by the end of this year.
Central Arizona Project
As of today, Arizona receives approximately 2.8MAF of water from the Colorado River via the CAP. Of our total allotment, 1.6 to 1.7MAF goes to active management areas fed by the CAP and the remainder goes to tribes and other priorities. 40% of CAP water is used for crops, 33% goes to water treatment plants, 22% goes to direct recharge and 5% goes towards other uses. Due to drought conditions, we are now in a Tier 1 shortage which means Arizona’s portion of Colorado River water was reduced by 500,000 acre feet.
Scottsdale Water
As of the most recent census, the population of Scottsdale is approximately 250,000–a final buildout of our city would yield a population of around 310,000. There are 93,800 active water accounts for potable and non-potable water with an estimated delivery of 82 million gallons per day! Here is how Scottsdale water use breaks down:
- Municipal: 54%
- Multi-family: 16%
- Commercial: 14%
- Turf irrigation: 16%
One very important consideration for Scottsdale residents is that 76% of water delivered comes from the CAP. If our state allotment from the CAP is cut further, this could have dire effects for our city. Currently Scottsdale is in a Tier 2A shortage which translates to a reduction of 3 million gallons per day.
Summary
While recent rains have helped recharge our lakes, Arizona remains in a drought and water use will become more of a hot topic as the population increases. We are already seeing restrictions on building/development in many areas. If you are looking for more information about Arizona water, check out the following links:
Arizona Department of Water Resources
Photo credit: Photo by Aleksandr Slobodianyk
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