Alert: Possible Harmful Algal Bloom at Martinez Marina

The City of Martinez is warning the community about the possibly harmful algal bloom in waters at the Martinez Marina. These blooms can pose serious health risks to people, pets, and wildlife.

It is recommended to:

  • Avoid contact with the water
  •  Keep pets away
  • Do not swim in affected areas

Signage advising of these precautions has been posted at the Marina. Additionally, you may view information on the possible bloom on the State Water Quality Monitoring Council website at: https://mywaterquality.ca.gov/habs/resources/reports-map/. The City is monitoring the situation and coordinating with other agencies, and will provide updates as conditions change.

Information released by the City of Martinez

Delta – Martinez Marina – MARTINEZ Marina
Latitude:  38.026 Longitude:  -122.138
County: Contra Costa Regional Water Board: Region 2 – San Francisco Bay
Waterbody Manager: Public entity Land Manager:
Report ID: 4935 Info for this report provided by the following Organization:  EBRPD
_______________________________________________________________________________________________
Report Updated On:   8/1/25     Report Submitted On: 8/1/2025 9:42:15 AM
Current Advisory: Refer to report details
Advisory Recommendations:  No bloom advisory. Refer to “Report Details” for additional info.
Report Details:  Visual observation of harmful algal bloom from shoreline or boat. Water testing was not conducted to measure toxicity of bloom according to statewide guidelines. Contact the water or land manager listed above to request water testing due to the confirmed visible bloom.
The exact location, extent and toxicity of the reported bloom may not be accurate and may not be affecting the entire waterbody.

7/31 – Contra Loma Reservoir

Contra Loma Reservoir – Contra Loma Reservoir, at Regional Park

Latitude:    37.973      Longitude:  -121.824

County: Contra Costa Regional Water Board: Region 5 – Central Valley

Waterbody Manager: Land Manager: East Bay Regional Park District

Report ID: 4039 Info for this report provided by the following Organization:  East Bay Regional Park District

_______________________________________________________________________________________________

Report Updated On:   7/31/25     Report Submitted On: 1/27/2023 1:03:37 PM

Current Advisory: Danger

Advisory Recommendations:  STAY OUT OF THE WATER. Do not touch scum in the water or shore. Do NOT let pets go in the water, drink the water, or eat scum on the shore. Do not eat shellfish from this waterbody.

Report Details:  Advisory applies to the full extent of the lake or reservoir (lake-wide advisory) and is not to limited the location symbolized by this report. Updates to this report are provided by a routine water monitoring program conducting site visits at this waterway, refer to Organization field above for more information.

The exact location, extent and toxicity of the reported bloom may not be accurate and may not be affecting the entire waterbody.

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