Elevated bacteria levels forced 47 Suffolk County beaches to restrict swimming Friday.

Officials say storm runoff from heavy rain pollutes the water and forces the red flags alerting swimmers the ocean is off-limits. Youngsters attending a once-a-year YMCA beach party in Bay Shore said they were disappointed they couldn?t cool off after a football game.

Suffolk officials say they are evaluating new technologies that filter runoff and prevent ocean contamination. Environmental groups say they are losing patience and immediate action must be taken to protect the shoreline.

Thirty-five Suffolk beaches lifted swimming restrictions throughout the afternoon. Nassau and New York State beaches were not affected.