J. Wayne Miller, Ph.D. Water Treatment Plant is the nation's largest Per- and polyfluoralkyl substances (PFAS) water treatment plant, constructed in recent years as a partnership between the Yorba Linda Water District and the Orange County Water District in California. This cutting-edge facility is addressing a pressing public health issue: the existence of PFOA and PFOS, manufactured chemicals that are part of a larger PFAS family known as "forever chemicals."

Yorba Linda is a small city southeast of Los Angeles, known as the birthplace of President Richard Nixon. The plant there has been operational for nearly three years, using specialized resin technology to filter PFAS chemicals from the local water supply. Twenty two giant tanks are filled with polymer resin beads that remove PFAS from the water. Each tank holds around 4,500 gallons, and the plant serves 80,000 residents.

The Environmental Protection Agency (EPA) has estimated that thousands of water systems across the U.S. serve approximately 100 million people, potentially exposing them to harmful levels of PFAS. New EPA regulations, finalized in April, require water districts to take action, making Yorba Linda's plant an example of how communities can address the issue.

Yorba Linda faced a significant PFAS issue in 2020 when all 10 of its groundwater wells exceeded California's recommended limits for PFAS. The state set these limits before federal regulations, which put California cities like Yorba Linda ahead of the curve. 

Across Orange County, several other cities, including Anaheim, also face PFAS contamination. Anaheim, which serves over 500,000 people daily, took many of its wells offline in 2020 due to excessive PFAS levels. The city initially switched to imported water sources, but this increased costs significantly, leading Anaheim to construct its own PFAS filtration tanks. Building these filtration systems is expensive but still more cost-effective than relying on imported water.

With the EPA's new, stricter standards for PFAS in drinking water, Anaheim and other cities are expanding their treatment capacity to meet federal requirements. Anaheim's efforts to treat its 19 wells are projected to cost $200 million, while across Orange County, fixing the PFAS issue is expected to total $1.8 billion over 30 years.

A significant source of PFAS contamination in the area appears to be the Santa Ana River, which collects runoff containing PFAS as it flows through cities, industrial areas, and military bases. Water from the river seeps into the ground, refilling groundwater supplies and introducing PFAS.

Despite the progress made in Yorba Linda and other parts of Orange County, experts warn that wells not currently contaminated may face future challenges as water moves through the region. However, the county is positioned to respond with its early investments in treatment infrastructure. Nonetheless, as PFAS contamination remains a widespread problem, Orange County's lead in managing PFAS could eventually be surpassed by other areas facing similar challenges.