Not lifeguarded.

Popoi’a Island, popularly known as Flat Island, is one quarter of a mile seaward of the boat ramp. Popoi’a means rotten fish, and may refer to offerings that were left at a former fishing shrine in the middle of the island. The tsunami of 1946 destroyed the remnants of the shrine. Landing is permitted on the island’s small sand beach, although Popoi’a is part of the Hawai’i State Seabird Sanctuary. A popular surf site known as Flat Island breaks on a shallow reef on the island’s south side.

This description is taken from John R. K. Clark's book - Beaches of Oahu (Revised Edition) which is published by University of Hawai'I Press and available from University of Hawai'I Press. We thank John R. K. Clark for providing his description of Hawaii's beaches to improve beach safety.