Last month, water treatment plant operators from Scottsdale Water quietly completed a major behind-the-scenes effort to keep Scottsdale’s corner of the desert thriving. At the city’s Advanced Water Treatment facility, located at the Scottsdale Water Campus, crews replaced hundreds of reverse osmosis (R.O.) membrane sections—an essential component of Scottsdale’s award-winning water purification system.

The world-renowned facility features 24 R.O. “skids,” each holding multiple long, 8-inch-wide pressure vessels. Inside each vessel are membrane sections that play a critical role in water purification and are typically replaced about every seven years. To ensure uninterrupted water production and responsible financial planning, Scottsdale Water performs this work in phases, spreading the effort and cost across multiple fiscal years.

Reverse osmosis is one of several advanced treatment steps used to transform conventionally treated wastewater into highly purified water that meets drinking water standards. R.O. membranes act as ultra-fine filters, removing compounds based on size, molecular weight, or electrical charge by forcing water through a semi-permeable barrier. Water molecules pass through, while salts, dissolved solids, organics, and microorganisms are left behind.

Before reaching reverse osmosis, water at the Scottsdale Water Campus undergoes ozonation and ultrafiltration. After R.O., it receives a final layer of protection through ultraviolet photolysis disinfection. From there, the purified water serves two important purposes: it is delivered to golf courses in northern Scottsdale via the Reclaimed Water Distribution System, or it is injected through dry wells into the city’s drinking water aquifer.

After spending about a decade underground, that same water can be recovered by Scottsdale Water’s groundwater wells, blended with other water supplies, and ultimately returned to customers’ taps—safe, clean, and reliable.

Since 1988, Scottsdale Water’s dedicated operators, technicians, and scientists have reused nearly 75 billion gallons of purified water through these processes, helping secure a resilient water future for the community.

There is truly no treatment plant quite like Scottsdale’s Advanced Water Treatment facility. To learn more about this innovative system, visit ScottsdaleAZ.gov, and search “Advanced Water Purification.”