Tomales Bay: toxic algae advisories

Tomales Bay, Marin County. See all Marin County waters.

What the state's records say

Caution advisory, last posted Oct 31, 2024. No all-clear recorded.

Reporting is voluntary, so the state may not have recorded an end even if conditions changed. Check posted signs and the official map.

What this level asks: Algae that can make toxins may be present. Keep people, children and pets away from algae and scum, and do not let pets drink the water.

Before you go, check the state's official algae page and any signs posted at the water.

Dogs at Tomales Bay

The state has an advisory on file for Tomales Bay (Caution advisory), last posted Oct 31, 2024, and no all-clear recorded. Keep your dog out of the water and away from scum on the shore until the state records an end.

Reported spots

The state records each report at a spot, such as a beach or a boat ramp. Each spot's latest deciding record:

Each reported spot at Tomales Bay and its latest status
Spot	Status
Dillon beach	Caution advisory, last posted Oct 31, 2024. No all-clear recorded.

Advisory history

Every advisory record the state has published for Tomales Bay, newest first. "None" is the state's record that no advisory was recommended on that date. "NA" records do not change a status.

Advisory records for Tomales Bay, newest first
Date	Spot	State's level	Notes
Oct 31, 2024	Dillon beach	Caution	Marine bloom present (red tide)

Source

Advisory data: California State Water Resources Control Board, Freshwater Harmful Algal Bloom Program, via data.ca.gov (public domain). Advisories are recommendations; reporting is voluntary and incomplete. The state's data. An advisory ends only when the state records a later "None" (no advisory recommended) at the same spot, or an end date. A blank end date is unknown.