McNears Beach in San Rafael earned a C grade for water quality in Heal the Bay's 2026 annual Beach Report Card, making it the only non-creek beach in Marin County to fall below an A during the summer dry period.

The grade, based on fecal bacteria levels, comes as the county recorded 10 sewage spills releasing a total of 55,000 gallons of raw sewage during the reporting period, according to the Heal the Bay report. The largest single spill, in early 2026, dumped 42,000 gallons after what the report described as historic King tides, an atmospheric river, and lagoon stormwater that overwhelmed the local collection system.

Countywide, just 78% of monitored sites received an A grade for dry summer weather. That's a sharp drop from the five-year average of 97%.

"That drop is notable because it happened during a drier-than-normal year, when we'd normally expect water quality to improve, not decline," Arti Kundu, project manager for Marin County's Environmental Health Services Division, told the Marin Independent Journal in a story published Friday, July 25.

Marin received about 21 inches of rain between April 2025 and March 2026, roughly 8% below the 10-year average. Drier years almost always produce better scores because less runoff washes bacteria into waterways. Kundu said the decline despite low rainfall points to persistent contamination sources such as groundwater seepage, aging sewer infrastructure, or wildlife inputs.

The county's Environmental Health Services Division said in a statement that the spills "were promptly reported, and appropriate measures were taken to mitigate any potential impact on the environment and public health."

Over the past year, 23 of the county's 31 monitored sites had at least one water quality advisory warning, Kundu said. As of the sampling week of Monday, July 13, five sites carried active advisories: Chicken Ranch Ditch at Channel B, Inkwells, Green Bridge, Whitehouse Pool, and Dillon Beach Ditch. McNears Beach was not among them.

The report also gave F grades to two Lagunitas Creek sites and a D to a spot near the Green Bridge south of Point Reyes Station. But no Marin beach landed on Heal the Bay's statewide "beach bummer" list of the 10 worst sites, an improvement from last year, when Chicken Ranch Beach ranked fourth.

Rebecca Schwartz Lesberg, executive director of the Marin Conservation League, told the Marin Independent Journal that the spill data underscores the need to invest in aging stormwater and wastewater systems across the county.

Residents can check weekly water quality results at the county's beach monitoring page (marincounty.gov/departments/cda/env-health-svcs/prgm-beach-water-monitoring) or call Environmental Health Services at 415-473-7146.