Increased storm runoff and urban infrastructure failures drive down water safety grades.
Chronic bacterial pollution has landed the Santa Monica Pier in the number two spot on California’s annual “Beach Bummers” list, anchoring a statewide water quality report that links increased storm runoff to declining safety grades at local shorelines and rivers.
The environmental nonprofit Heal the Bay released its 36th annual Beach Report Card and 8th annual River Report Card, translating bacterial monitoring data from more than 700 Pacific Coast beaches and 35 Los Angeles freshwater sites into standard academic letter grades. While an A or B grade indicates water that is generally safe for swimming, ratings of C through F signal an elevated risk of contracting illnesses, including gastrointestinal distress, respiratory infections, ear problems, and skin rashes.
Environmental analysts attributed the regional drop in water quality to wetter weather patterns. Although 91% of California beaches maintained A or B grades during the dry summer season, winter storms and urban runoff caused significant grade drops across Southern California.
A similar geographic pattern emerged in freshwater environments, where water quality remained high in open-space upper watersheds but degraded rapidly as rivers flowed through heavily urbanized stretches of the Los Angeles River. The recurrence of identical pollution hotspots across both reports underscores systemic infrastructure vulnerabilities, such as aging sewage systems, low-flow stagnation, and unmitigated toxic runoff.
Unlike coastal beaches, where county health departments are legally mandated to conduct weekly bacterial testing, freshwater recreational areas lack standardized monitoring requirements. To bridge the data gap, Heal the Bay utilizes its “Stream Team” of trained student scientists alongside municipal partners to sample and evaluate inland waterways from May through September.
To address the ongoing contamination at the Santa Monica Pier, Heal the Bay has formed a joint task force with the City of Santa Monica to isolate and mitigate the chronic wastewater and storm drain discharges plaguing the tourist landmark.
Public health officials and researchers advise ocean and river recreators to check real-time grades via the Beach Report Card app before entering the water, to remain away from storm drains and enclosed stagnant basins, and to strictly avoid swimming for at least 72 hours following any rain event.
