Police and lifeguards will begin closing entrances to the beach between Neptune Boulevard and New York Avenue, the main boardwalk stretch, and delivering warnings at 7:45 p.m.
Police, seasonal officers and bike patrols will then start closing the boardwalk at Edwards Boulevard, moving east and west. A smart car will follow people off the boardwalk.
"It's necessary," said Acting Police Commissioner Phil Ragona. "It's really important. And if we don't do this now, I really believe there could be dire consequences down the road. Some people think it's drastic. I don't. I think it's necessary."
"It is absolutely a work in progress," he added.
RELATED: Jersey shore borough passes new rules to curb bad beach behavior
The city traditionally keeps the beach open from 5 a.m. to 11 p.m., with swimming ending at 6 p.m. when lifeguards go off duty.
But large crowds, including more than 800 caught on camera Saturday night drinking and fighting, prompted city leaders to restrict beach and boardwalk access.
Now the beaches will be gated off at 8 p.m. and reopen at 5 a.m.
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