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Harmful Algae Blooms

Science beakers with green liqquid

The District does not currently monitor for Harmful Algae Blooms (HABs), as guidance from the California State Water Resources Control Board on HAB monitoring focuses on water bodies supporting contact and non-contact recreational uses. District canals function as a conveyance for stormwater in the winter and agricultural drainage in the summer. All contact and non-contact recreation, including, but not limited to swimming, boating, and fishing IS PROHIBITED in waterbodies owned, operated, and managed by the District. Additionally, residents must keep their pets out of District waterbodies if using walking paths adjacent to District conveyances.


If you suspect the presence of a HAB, you may report the bloom using the Water Quality HAB Page’s Freshwater HAB Report form ( Once reported, the Office of Environmental Health Hazard Assessment should follow-up with the California Department of Fish and Wildlife to track relevant data.