You needed a 4-wheel drive to get access to this beach in the past but now it is open to everyone. In October 2005, a new paved road was completed leading to Kua Bay. Because of its small parking lot, be advised that there is only limited parking so get there early. Part of Kekaha Kai State Park, this is one of the nicest and secluded beaches on the island with white sand. It is a very picturesque beach with soft white sand, a sandy bottom and crystal clear waters. The weather is usually very sunny on this stretch of coastline so bring a lot of sunscreen. The surf can get rough here so it is not an ideal beach to snorkel or go shore diving. There are picnic tables, restrooms and showers but no lifeguard. It is an ideal beach to fish and picnic at. Note that you have to walk over some lava rocks before you reach the sandy section of the beach. At low tide the water is wonderful to swim and wade in. Do not swim at this beach when the surf is high or when there is a westerly swell during the winter months because the currents here are strong and there is no lifeguard. The water may look safe to enter but the currents and the waves may sweep you out into the open ocean. To get to Manini'owali from Kona, take route 19 north (drive about 13.2 miles) on Queen Ka'ahumanu Highway, then turn left at the sign on left that reads Kekaha Kai State Park-Manini'owali section. I would recommend this beach to visitors only on a calm day when the surf is low.
From journal Beaches on the Big Island of Hawaii