Myrtle Beach, SC Laws

Swimming/Sunbathing
Swimming is not permitted beyond 50 yards from the beach or over shoulder depth, unless otherwise stated by the lifeguard.
Jumping or diving from piers is prohibited. Swimming within 50 yards of a pier is prohibited.
Only canvas/fabric rafts may be used in the ocean. Rafts must be equipped with safety ropes.
Swim wear is subject to city ordinances in Myrtle Beach, North Myrtle Beach, and Surfside Beach. It is illegal for anyone to wear a thong bathing suit.

Driving on the Beach
It is unlawful for any person to drive or operate a motor vehicle on the beach.

Sleeping on the Beach
Sleeping on the beach or at a beach access is not allowed between 9 p.m. and sunrise. (Try a hotel in Myrtle Beach instead.)

Fireworks
Possessing or discharging of fireworks is illegal within the city limits of municipalities along the Grand Strand. All establishments that sell fireworks within Horry County are required to post in a conspicuous location rules and regulations regarding fireworks.

Littering
Littering is illegal. Offenders may be required by law to assist officials in cleaning up the litter. All glass containers are prohibited on the beach.

Alcohol
Possession or consumption of alcohol is prohibited on the beach.
Glass containers/bottles are not allowed on the beach.
Driving under the influence of drugs or alcohol is illegal.
It is unlawful for any person under the age of 21 to buy, possess, or consume alcoholic beverages.
Open containers of beer, wine, or liquor are prohibited in vehicles or any public place including streets, sidewalks, and beach areas.
In Horry and Georgetown counties, restaurants and bars may sell alcoholic beverages on Sunday. In addition, all liquor stores open at 9 a.m. and must close by 7 p.m. Monday through Saturday.
Store purchases of alcoholic beverages are prohibited from midnight Saturday through midnight Sunday.
Thanks to a recent law, stores with a special sales permit may sell beer and wine on Sundays. Stores with this permit include many grocery stores and all Grand Strand area Wal-Mart Supercenters.

Vehicle Laws
Seat belts must be worn at all times in a moving vehicle.
Vehicle headlights must be on if operating windshield wipers due to rain or poor road conditions.
Motorcyclists are required to use headlights at all times.
New restrictions have been passed restricting motorcyclists in the city limits of Myrtle Beach.
Children 17 and younger must be restrained at all times in a moving vehicle by means appropriate for the child's age and seating location, according to the National Highway Traffic Safety Administration.
Right turns may be made on a red light, except where a sign denotes "No Right on Red." You must stop before turning and yield right-of-way to traffic already in the intersection.
Driving under the influence of drugs or alcohol is illegal.

For more info:
City of Myrtle Beach Laws
North Myrtle Beach