Oneawa Beach
Located on the northern end of Kailua Bay near the Oneawa Canal there are fewer beach goers at this location primarily because of the lack of parking, access and beach facilities. It is also the location of a surf spot known as Castles. It is named after the fact that the Castle family at one time owned most of the land in the area.

This Kailua Bay location has more consistent wave action and the onshore winds create sand dunes and bring a lot of driftwood to the shore.

EPA Measuring Station
Oneawa Station is listed as a site with the Environmental Protection Agency for measuring marine water quality. After heavy storm the site ranks poorly due to the fact that the location is close to the mouth of Oneawa Canal. The canal carries flood and tidal waters of the Kawai Nui Subwatershed.