A beach on Lake Calhoun is closed to swimmers until at least next week because of E. coli concerns.

The Minneapolis Park and Recreation Board temporarily closed Thomas Beach at Lake Calhoun after weekly tests of the water quality Thursday found the bacteria exceeded state guidelines. Tests will be done again next week to determine if the water quality is safe and the beach can be reopened.

Spokeswoman Dawn Sommers said officials are being proactive and this is an isolated incident that could be the result of high water, rainfall or from more birds being in the area before tests were done.

"It's typically pretty isolated," she said.

During this hot July weekend, she said, swimmers have plenty of other options to cool off. All of the other 11 Minneapolis beaches, including two others on Lake Calhoun, remain open. For more information, go to www.minneapolis parks.org.

KELLY SMITH