About 2,500 gallons of untreated wastewater was discharged into the Hawai'i Kai Marina in Hawai'i Kai early yesterday morning after a car collided with a temporary sewer bypass line on Lunalilo Home Road.

Hawaii American Water, the private company that provides wastewater service in Hawai'i Kai, is warning the public to avoid water contact in the area of the marina stretching from a park at the corner of Kalanipu'u and Koamanu streets to the intersection of Hawai'i Kai Drive and Lunalilo Home Road. Warning signs will be posted in the area until testing results show that water quality has returned to normal.

"This will probably go on for at least three days. It will take us at least that long to analyze the results from our (water) samples," said Lee Mansfield, manager of Hawaii American Water.

In the meantime, marina users are being asked to avoid swimming, skiing or any other activity that exposes them to the water.

At about 2 a.m. yesterday, an unidentified vehicle hit a temporary sewer bypass line at 746 Lunalilo Home Road, said Mansfield. The untreated wastewater then entered the storm drain system and was discharged into the marina though an outlet on Kalanipu'u Street.

The bypass line is in place while Hawaii American Water upgrades its main sewer line on Lunalilo Home Road.

Mansfield said any witnesses to the early morning accident should contact police.

Yesterday the company planned to distribute leaflets to neighborhood residents warning them of the spill, said Mansfield. He said another set of leaflets will be distributed when the water is deemed safe.

Department of Health spokeswoman Janice Okubo said it is the responsibility of individual companies that own wastewater treatment facilities to warn residents when there is a spill of more than 1,000 gallons.

Reach Loren Moreno at lmoreno@honoluluadvertiser.com.