Otter island is a barrier island located well inside St. Helena Sound between the South Edisto and Ashepoo Rivers. Otter Island and neighboring Pine Island are separated from each other by Fishing Creek.
Otter Island is owned by the state of South Carolina under the authority of SCDNR. It is a Heritage Preserve and as such will be protected in perpetuity. The beach is narrow with low dunes interspersed with erosional areas. It has experienced erosional and accretional cycles in the last decade. Otter Island has 4.7 km of beach and from the air, the sand appears pink due to concentrations of crushed coquina shells. There are no modern structures or dwellings on the island, but it contains historic and archaeological sites.
Both Otter Island and neighboring Pine Island are accessible only by boat.