Five permit violations cloud an already-impaired Richardson Bay

August 6, 2026

Richardson Bay carries a state impaired-waters listing and a cleanup plan meant to draw down pollutants that have accumulated here for years. Against that backdrop, the current compliance picture among the watershed's permitted dischargers is worth noting. Of ten permitted facilities, including Marin County's Sanitation District No. 5 wastewater plant sited almost exactly at the bay's center, the Sausalito-Marin treatment plant, the Paradise Cove treatment plant, and several marine service yards, five currently have active permit violations and six have logged at least one violation in the past year.

None of these violations has risen to significant non-compliance, and no penalties have been levied. This isn't a dramatic spill or an enforcement crackdown; it's quieter and more persistent than that. A bay already flagged for cleanup is taking in discharge from treatment plants that aren't consistently holding to their own permit limits, month after month, without any single incident large enough to trigger a stronger response. Paradise Cove Beach, within this same bay system, carries its own separate impairment listing, which underscores how compounded the pressure on this shoreline already is.

Freshwater gauges on Redwood Creek near Muir Beach and Corte Madera Creek at Ross are currently reporting only streamflow and gage height, not temperature or dissolved oxygen, and in any case neither gauge sits on Richardson Bay itself, so neither speaks to conditions in the bay proper. That gap in direct monitoring matters most in late summer. Warm, still water holds less dissolved oxygen to begin with, and nutrient loading from wastewater discharge raises the risk of algal blooms just as the bay's tidal flushing is often at its weakest.

Watershed Alliance of Marin and Mill Valley Streamkeepers both track conditions in this watershed and are worth watching for any direct readings taken from the bay itself in the weeks ahead.

Data from EPA ECHO, Speak for the Trees org directory and USGS

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