Some restaurants closed, while others did not serve water or iced beverages Wednesday because of a water department advisory for Central and South Maui to boil drinking water due to possible contamination from Tuesday’s heavy rains and flooding.

Lahaina residents were told by the water department to conserve water immediately Tuesday morning because the Lahaina Water Treatment Plant was down. Central and South Maui residents also were asked to conserve water due to flood-related issues.

The county Department of Water Supply said there were no water quality violations as of Wednesday morning and that the advisory was a precautionary measure. The county said that waterlines were being flushed and that the results of tests of water samples should be available by noon today.

Until the results are in, the water department advised boiling water for three minutes or using bottled water. The state Department of Health, which was working in cooperation with the county water department, recommended that ice cubes made Tuesday and used for drinking or eating be discarded to avoid contamination and that soda machines drawing water should use boiled water or be turned off to avoid contaminating beverages.

The boil-water advisory covered restaurants, hotels, medical facilities and individual households, according to a county news release. The affected areas included Kahului, Wailuku, Paia, Spreckelsville, Puunene, Kihei, Wailea, Makena and Maalaea.

In response to the boil-water advisory, restaurants closed or limited their offerings. The state Department of Health notified restaurants by phone of the water notice and some of the potential restrictions, said Health Department spokeswoman Janice Okubo on Wednesday. For example, food preparation workers needed to wash their hands with bottled or boiled water.

Some restaurants in Wailuku were advised to close due to a water main break that cut off water, Okubo said. Water department spokeswoman Jan Inouye-Ogata said Wednesday that an old water main broke at 1321 Lower Main St. in Wailuku, and water was out for approximately five hours.

But in the rest of the cases, individual restaurants decided on their own how they wanted to deal with the water notice, Okubo said. Some restaurants may have closed because their soda and ice machines were tied to the water system with establishments unable to boil water before it entered the machines, she said.

“Cannot help,” said Roy Parilla, a manager at the Burger King at the Maui Marketplace on the eatery’s closure Wednesday. The closure was for the “safety of the customers,” he said, expecting the restaurant to open today.

Flatbread Co. in Paia posted on social media that it was closed for lunch and dinner Wednesday because of the water issue. “When health and safety are a priority. . . . take no chances,” the post said.

The Kahului KFC also closed Wednesday because of the water issues, said a manager who did not want to be identified.

At Sam Sato’s in Wailuku, the only problem was not being able to serve water to customers. And at nearby Tasty Crust, owner Curtis Takaoka said that the local diner was limited to serving chilled tea and other hot beverages for drinks. No soda.

He bought bottled water from Foodland and was expecting to head to Costco later Wednesday afternoon to buy more bottled water. He was not serving soda because his soda and ice machines tap directly into the water system.

Takaoka was contemplating buying ice if the advisory lasts longer, and he was cleaning his ice machine, “just to be on the safe side.”

The hot food operation was not really affected because meal preparation does not require much water and, if it does, the water is heated, Takaoka said. He did tell his staff Wednesday not to prepare food that used water.

Even at the Kalana O Maui building, the county’s seat of government, “out of order” signs were placed on water fountains to prevent people from taking a drink.

Due to the problem at the Lahaina Water Treatment Plant, west side water customers Wednesday were asked to conserve water. Inouye-Ogata said that the intake for the treatment plant was clogged by debris but was cleared Wednesday afternoon. Crews were working on restarting the treatment plant.

Unlike in Central and South Maui, the water on the west side was safe to drink, but a water tank that serves Lahaina was low, she said. Conserving water and avoiding unnecessary water use also will help preserve supplies for safety uses such as firefighting, according to a county news release.

The water department has a 24-hour hotline at 270-7633 if a water-related problem occurs or for those who may have questions.

* Melissa Tanji can be reached at mtanji@mauinews.com.