Oneawa Canal
Oneawa Canal is also known as Kawai Nui Canal. It was constructed as part of the Kawai Nui Marsh Flood Control. The project included this 9470 foot long trapezoidal channels. It starts at the base of Kawainui Marsh to Kailua Bay and is the only drainage canal for the marsh. The surrounding land is primarily residential and there are two major roadways, Mokapu Boulevard and Kainui Drive that run parallel on either side of the canal. Stormdrains from the bordering residential areas also empty into Oneawa Canal.

Oneawa Canal is influenced by the tides however it is blocked from intruding on the marsh by a wall of vegetation. The introduction of saltwater into the marsh beyond the head of the canal appears not to occur.

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