Rags and debris in a sewer line caused more than 550 gallons of wastewater to overflow in Kahului on Tuesday evening, Maui County reported in a news release.
The 566-gallon overflow from a sewer manhole occurred from 5:30 to 6:30 p.m. along Ani Street on Christmas Day.
The material entered a storm drain but did not reach the ocean or other waterways, the county said.
County workers cleared the line, pumped up the wastewater, and cleaned and disinfected the spill site before notifying the state Department of Health.
This sort of overflow can be avoided if residents would not flush cloth and other insoluble material down their toilets, officials said.
"We've found all sorts of things in our pipes that shouldn't be there," said Department of Environmental Management Director Kyle Ginoza. "Underwear, hand towels, feminine hygiene products and other items such as wet wipes should go into the trash can instead of the toilet. Wet wipes especially are a huge problem."
Most wet wipes, wet naps, moist towelettes and anti-bacterial hand wipes do not dissolve in water and can clog a drain as easily as rags and other insoluble refuse, the county said.
Some companies make flushable/dissolvable wipes, so residents are urged to check before deciding to flush items down the toilet.