MERCED COUNTY (CBS / AP) — Water officials are warning that a reservoir in the Central Valley has high levels of toxins from a cyanobacteria algal bloom that that has been in the reservoir for months.

The Fresno Bee reports that the California Department of Water Resources has upgraded the San Luis Reservoir level to “warning,” which tells people not to swim in the reservoir, to stay away from dirty water, and keep pets and children away from the algae.

It also says residents should not use the water for drinking or cooking. Fish should be cleaned with fresh water and shellfish caught in the reservoir should not be eaten.

The reservoir is in Merced County, about 125 miles southeast of San Francisco.

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