Water Quality
Kailua Bay is listed as an impaired water body under the Clean Water Act 303(d) by the Department of Health. There have been periodic exceedances of the water quality standards fro enterococci, nutrients and cholorphyll. It has occured at various sites along the beach however there has been no synchronization with the collecting of data and the City and County of Honolulu maintenance stream openings.

There is also indicator bacteria in the Kailua Beach sand. A significant source is improperly disposed of pet waste, diapers, and other sources of fecal matter which are often carried to nearshore waters when waves and tides washp up on the beach. Sunbathers on the sand also carry sand to nearshore waters during water activities.