It's a time when many people are hoping to take to the water for the 4th of July holiday.
Dangerous levels of blue-green algae mean no swimming, no boating, no fishing and no pets in the water at Lake Temescal and Quarry Lake in Fremont.
MORE: Is it still safe to swim in Bay Area waters amid toxic algae bloom? Experts weigh in
Experts weigh in on safety of Bay Area waters amid toxic algae bloom
Also, several lakes face advisories --including Del Valle Regional Park in Livermore and Lake Chabot in Castro Valley.
"Water quality does fluctuate. So we urge visitors to check East Bay Parks before they go for up to date information on the status of lakes and our parks," said Dave Mason is with the East Bay Regional Park District.
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