Scottsdale Arizona Water Supply Problems Explained

The consequences of a long-standing drought in the American Southwest have been acutely felt by one desert community in Arizona. On January 1, the city of Scottsdale cut off its water supply to Rio Verde Foothills, forcing residents to turn elsewhere to meet their water needs.

The announcement came in the wake of severe water shortages in Scottsdale, which forced the city to conserve its precious supplies for its own residents. The Rio Verde Foothills, an unincorporated community just outside Scottsdale's city limits, is governed by Maricopa County. The community does not have an in-built water main network and instead relies on groundwater wells and water hauled in from neighboring towns.

For years, Scottsdale has allowed members of the community to haul water from the city's municipal water-fill stations. But in October 2021 the city said it would no longer be able to allow nonresidents to use the city's water supply.

"The reason for Scottsdale to take this action is that we're looking at cuts in Colorado River deliveries," Sarah Porter, director of the Kyl Center for Water Policy at Arizona State University, told Newsweek. "Scottsdale is reliant on some amount of Colorado River water, and it needs to protect those supplies."

The river's dwindling water supplies are a result of the steady decline of water levels in Lake Mead, the nation's largest man-made reservoir. "Lake Mead holds water for Arizona, California, Southern Nevada and Mexico," Porter said. "There's a big agreement in place, called the drought contingency plan, where certain agreed-upon cuts in deliveries are taken when Lake Mead falls to certain levels."

The first cuts were made in August 2021, when the U.S. Bureau of Reclamation declared the first Tier 1 shortage for the Colorado River system, effective from January 2022. The Tier 1 shortage reduced how much water Arizona was allowed to use from the lower Colorado River in response to water levels in Lake Mead dropping to below 1,075 feet above average sea level.

In July 2022, Lake Mead levels hit a new low, 1,040 feet—the lowest since its construction in the 1930s. As a result, the Bureau of Reclamation issued additional cuts to the system, placing the Lower Colorado River Basin under a Tier 2a shortage for 2023. Water levels are still only at 1,046 feet today, in spite of recent rain.

Scottsdale has a very advanced system for treating and recycling wastewater, which allows it to keep its supplied water within its water delivery system for longer. "Almost everyone in Scottsdale is on a sanitary sewer system, so all of the water that is used indoors can be reclaimed, treated and reused," Porter said.

Rio Verde Foothills does not have a sanitary sewer system. Instead, the community relies on septic systems, which means the water supplied to Rio Verde cannot be recycled. As a result, Porter said, the community was like a "leak" in the city's carefully managed water system.

"Scottsdale has no control over the demand or over how big [the community] gets," she said.

In light of these supply issues, Scottsdale decided to notify all water-hauling customers that unless their water was being used within the city's limits, they would no longer be able to collect it as of January 2023. This included the water haulers that supply Rio Verde Foothills.

Since the start of 2023, Rio Verde residents have resorted to drastic measures to cut down on their water usage. They have had to rely on water hauled in from much further away, which is more expensive. The New York Times reported that residents are now skipping showers and using paper plates to avoid washing dishes.

However, Porter said that the situation in Rio Verde Foothills is very unusual.

"Most people have their water delivered from a drinking water plant. It's really a very unusual situation for people to rely on hauled water from another city, a city that they are not part of, that they are not paying taxes in, where they are not voting," she said. "And from a water management perspective, Scottsdale needs to protect its water supplies for its own residents that it is obligated to serve."

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