Sonoma County Airport WWTF - Santa Rosa, California Wastewater Treatment Plant

The Sonoma County Airport Wastewater Treatment Facility (WWTF) is located at the Westside Transfer Center in Santa Rosa, California, within Sonoma County. This plant serves a small population of 370 people and is part of the municipal wastewater infrastructure for the airport area. The plant provides secondary treatment, which is the standard level required by the US Clean Water Act for most municipal facilities. With a designed capacity of 302.83 megaliters and an annual discharge volume of 113.56 megaliters, it operates well within its capacity. As a US facility, it is regulated under the National Pollutant Discharge Elimination System (NPDES) permit program, administered by the California State Water Resources Control Board. The treated effluent is discharged into local waterways that ultimately drain to the Pacific Ocean via the Russian River or other Sonoma County watersheds. The plant's location within 50 km of the coast means its discharge can affect coastal water quality, though it is not directly coastal. The facility plays a role in protecting the ecologically sensitive Russian River estuary and the marine environment of the Pacific.

The plant discharges into the Russian River watershed, which flows through Sonoma County and empties into the Pacific Ocean at Jenner. The Russian River supports diverse aquatic life, including steelhead trout and coho salmon, and its estuary is an important migratory corridor for birds. The plant's secondary treatment helps reduce nutrient and pathogen loads, protecting downstream water quality and the sensitive coastal ecosystem.