Bethany Reservoir: toxic algae advisories

Bethany Reservoir, Alameda County. See all Alameda County waters.

What the state's records say

The state's latest record, from Sep 26, 2024, recommends no advisory.

Last advisory on file: Sep 5, 2024.

That reflects what the state knew on that date. It is not a finding that the water is safe now: blooms can return within days, and many are never reported.

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

Dogs at Bethany Reservoir

The state's latest record, from Sep 26, 2024, recommends no advisory. For Bethany Reservoir, that is not the same as an all-clear for today. Look at the water before your dog goes in: keep it out of green, blue-green or scummy water and away from mats on the shore.

More on dogs and toxic algae.

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 Bethany Reservoir and its latest status
SpotStatus
Downstream of Banks Pumping Plant The state's latest record, from Sep 26, 2024, recommends no advisory.

Advisory history

Every advisory record the state has published for Bethany Reservoir, 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 Bethany Reservoir, newest first
DateSpotState's levelNotes
Sep 26, 2024 Downstream of Banks Pumping Plant None Testing results below posting triggers; Updates from routine monitoring program-organization
Sep 20, 2024 Downstream of Banks Pumping Plant None Testing results below posting triggers; Updates from routine monitoring program-organization
Sep 5, 2024 Downstream of Banks Pumping Plant Caution Advisory based on visual and toxins; Lake-wide advisory; Updates from routine monitoring program-organization

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.