Rio Dell WWTF - Wastewater Treatment Plant in Rio Dell, California

Rio Dell Wastewater Treatment Facility (WWTF) is a municipal treatment plant located in Rio Dell, Humboldt County, California. The plant serves a population of about 3,100 people, reflecting a small community in the coastal region of Northern California. As a publicly owned treatment works (POTW), it operates under the regulatory framework of the U.S. Clean Water Act, which requires National Pollutant Discharge Elimination System (NPDES) permits for all discharges to surface waters. The plant's designed capacity is 1.00 million gallons per day, indicating it is sized to handle the wastewater flows from the local community. Plants of this scale in California typically employ secondary treatment as a minimum, often with additional nutrient removal or disinfection to meet state water quality standards. The facility is subject to oversight by the California State Water Resources Control Board and the North Coast Regional Water Quality Control Board. The treated effluent from Rio Dell WWTF is discharged into the Eel River watershed, which flows through Humboldt County and ultimately reaches the Pacific Ocean. The Eel River is a major coastal river in California, supporting diverse aquatic life including salmon and steelhead trout. The plant's operations are critical for protecting water quality in this ecologically sensitive river system and downstream marine environment.

Rio Dell WWTF discharges into the Eel River watershed, which drains to the Pacific Ocean near the Humboldt Bay region. The Eel River is a vital habitat for anadromous fish species such as Chinook salmon and steelhead trout, and its estuary supports a rich diversity of birds and marine life. The plant's effluent must meet stringent water quality standards to protect these downstream ecosystems, particularly during low-flow summer months when dilution capacity is reduced.