In powerful waves with up to 12-foot faces today on Oahu’s South Shore, Honolulu Ocean Safety personnel made 271 rescues, and took over 2,100 preventative rescues, the Honolulu Emergency Services Department reported shortly after 4 p.m.

“Many of the rescues came in the form of surfers in over their head, surfers who broke boards and leashes and needed help to shore,” EMS officials said in a news release, adding that a big south swell, which rose quickly from Sunday evening, “has caught those without a lot of experience off guard today.”

Noting that lifeguards always recommend watching the surf before entering the ocean, the department advised that beachgoers talk to a lifeguard before entering the water during big-wave episodes. EMS says lifeguards can tell beachgoers about conditions in the swell and where to find a safer beach.

Sheer rock areas like China Walls are extremely dangerous in large swells, the department noted, because the currents and waves striking the cliffs make it nearly impossible for beachgoers to pull themselves out of the ocean.

EMS reminded people not to turn their backs to the ocean at the shoreline, where a large wave could pull them into the water, to always surf and swim with a buddy, know their location, and to call 911 immediately if they see anyone in trouble.

“Be smart. The ocean can look calm or manageable but can change very quickly,” the EMS said.