HONOLULU -- Weeks of heavy rain have begun to overload Oahu's sewage system.

At least a half dozen sewage spills and overflows of wastewater were reported on Sunday on the windward side.

The worst of the sewage spills occurred in Waikiki, where a broken sewer line spilled an estimated 375,000 gallons of untreated wastewater into the Ala Wai Canal.

The break in the 42-inch main that serves Beachwalk Wastewater Pumping Station was discovered Friday morning on Kaiolu Street.

Heavy rains entered the aging wastewater system and threatened to overwhelm it. To avoid a larger problem, crews diverted the wastewater directly into the canal and out to sea.

Officials said they could not shut down the pump station because it serves such a large area and would be too disruptive.

Crews hope to be able to patch the broken pipe soon.

"We're going to continue the patching of the pipes where there are cracks," said Eric Takamura, director of environmental services. "Where we can, we're going to put a sleeve around it. Then, we're going to pour the concrete jacket."

Takamura said continuing rains are making the repair process even more difficult.

He said crews need about a day and a half of dry weather to make sure the concrete sets properly.

"Once the concrete goes in, we need to let the concrete set and harden for another 24 hours," said Takamura.

While crews work to repair the sewer line, warning signs remain posted along the Ala Wai canal and various points downstream.

City crews patrolled the banks and warned people to stay away from the water. They also cautioned surfers near the mouth of the canal.

Officials said the current is flowing straight out, so they have not had to close any beaches in Waikiki.

The Department of health is being advised about the bacteria levels.