Residents of Trenton and four neighboring municipalities - Hamilton, Ewing, Hopewell and Lawrence - are being advised to boil tap water due to an equipment malfunction, officials said Friday.

Trenton Water Works, the city’s 160-year-old municipal water utility, also serves residents in the surrounding areas.

The utility, which has grappled with an aging infrastructure and related concerns, announced at 6:16 a.m. Friday that an equipment malfunction in the water distribution system had resulted in low chlorination levels which are needed for the water disinfection process.

N..J. Department of Environmental Protection spokesperson Larry Hajna explained that water not fully disinfected “could carry bacteria that could make people ill if consumed.”

Boiling kills bacteria, and other organisms, in the water.

A spokesperson for Trenton Mayor Reed Gusciora said the problem was addressed “within minutes.”

“The system worked as it is supposed to. There was an equipment malfunction and TWW detected lower than usual levels of chlorine in the water during the early morning," the spokesperson, Connor Ilchert, said via email at 1:31 p.m.

“DEP wanted us to be precautious and send out the advisory until testing is finished, and we get the green light. We will be keeping everyone informed as we remediate the situation to maintain our full transparency,” he said.

Residents were notified by the city of Trenton via reverse 911 phone calls and outreach to the media, Hajna said.

The advisory recommends that residents either use bottled water, or bring tap water to a rolling boil for one minute and allow the tap water to cool before using.

Boiled or bottled water should be used for drinking; preparing foods; mixing baby formula, food, juices or drinks; washing vegetables and fruit; cooking; making ice; brushing teeth; and washing dishes until further notice, according to the advisory.

Trenton Water Works is also recommending the following precautions:

Discard uncooked food, beverages, or ice cubes made with tap water during the day of the advisory.

Keep boiled water in the refrigerator for drinking.

Do not swallow water while showering or bathing.

Rinse hand-washed dishes with a diluted bleach solution (one tablespoon of household bleachper gallon of tap water) or clean your dishes in a dishwasher using the hot wash cycle and dry cycle.

Do not use home filtering devices in place of boiling or using bottled water; most home water filters will not provide adequate protection from microorganisms.

Only boiled water to treat minor injuries.

Provide pets with drinking water that has been boiled (and cooled).

No timeframe has been provided for lifting the advisory, which initially applied to residents of four municipalities but was subsequently expanded to include Hopewell, the utility said.

Trenton Water Works services approximately 225,000 people in Trenton, parts of Hamilton Township, Ewing Township, Lawrence Township and Hopewell Township in Mercer County, according to the utility’s Facebook page.

Residents with questions may contact Trenton Water Works at (609) 989-3033.

Rob Jennings may be reached at rjennings@njadvancemedia.com. Follow him on Twitter @RobJenningsNJ. Find NJ.com on Facebook.

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