Obstruction Island is one of the San Juan Islands in San Juan County, Washington, USA. It lies off the southeast tip of Orcas Island, between it and Blakely Island. Obstruction Island has a land area of 0.882 km² (0.3406 sq mi, or 218 acres). The 2000 census reported a permanent population of eight residents.

References

• Obstruction Island: Blocks 3040 thru 3044, Census Tract 9601, San Juan County, Washington United States Census Bureau