The city of Boca Raton is prohibiting swimming at all its beaches after results from testing at two sites showed high bacterial levels in the water.

The citys beaches will remain open to the public, with red flags and signs at its entrances enforcing no swimming.

Full use of the beaches may resume within the next 24 to 48 hours once results are in from additional water samples.

Testing takes about 24 hours, so [by Thursday], we should know if its clear or not, said Chrissy Gibson, Boca Ratons spokeswoman.

A health advisory was issued for beaches at Spanish River Park and South Inlet Park after they were listed in the poor range because of recent sampling, the Palm Beach County Department of Health said Wednesday.

Beach waters at 13 locations from Boca Raton to Jupiter are regularly tested by health department workers and, following laboratory testing, concentrations of bacteria are assigned to indicate poor, moderate or good ranges.

The cause of the elevated bacteria levels isnt known, but typical causes include runoff following heavy rains, high surf from high winds and high tides, heavy recreational usage and wildlife.

Such bacteria can lead to infectious diseases, especially for someone with an open wound or a compromised immune system, said health department spokesman Tim OConnor. Additionally, it has an entry point if swallowed.

You can find water quality listings for beaches in Palm Beach County and throughout the state at http://www.flhealthpalmbeach.org. Click the link to Beach Water Sampling.

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Boca Raton prohibits swimming at beaches after high bacteria levels found at two sites - Sun Sentinel