AUSTIN — Warmer temperatures, longer daylight hours and nutrients in the water mean that algae blooms are on the rise again in area waterways, according to LCRA scientists.

LCRA scientists have reported algae blooms in a number of area creeks as well as lakes Buchanan, LBJ and Travis. Algae blooms in Lake Travis are believed to be the source of taste and odor problems reported in the past few days by residents of Cedar Park, which gets its water from the Sandy Creek arm of Lake Travis. In response, Cedar Park has taken additional steps to treat the drinking water to address the problem.

Algae are aquatic plants that are typically present in small quantities in water bodies and are kept in check by algae-eating fish. Filamentous, stringy algae are prominent in streams, while free-floating algae are common in the lakes. Sometimes under the right conditions, such as warming temperatures and light, algae can grow so fast that the water turns green. This is called an algae bloom.

"Just as springtime brings out the greenery on land, it also happens in the water," said John Wedig, an LCRA aquatic scientist. "The unusually heavy and frequent rainfall since last fall also has contributed significantly to algae growth by washing nutrients into area waterways." The algae blooms are typically naturally occurring and are not harmful to people. Nevertheless, these aquatic plants can be unsightly and can be a nuisance to boaters and swimmers, according to Wedig.

Since the Highland Lakes are a source of drinking water, residents may notice temporary problems with water taste and odor as a result of the algae blooms, he said. Although treatment facilities are able to remove the algae, some of the taste and odor-causing compounds may be left behind.

While the blooms may be a nuisance to some people, many of these algae serve as the base of the food chain, providing an abundant food source for small fish and insects, Wedig said.