UPDATE: The boil-water advisory in Trenton, Ewing and Hamilton has been lifted, the Department of Environmental Protection said Tuesday afternoon. Results were negative for total coliforms and indicated adequate chlorine residuals, and the DEP will continue to monitor the situation.

The state is advising residents of Trenton and parts of two neighboring towns to boil their tap water before using it due to a treatment plant malfunction early Monday.

Trenton Water Works issued a boil order to customers on Monday morning due to "inadequate treatment according to a report from the NJ Department of Environmental Protection's Water Resource Management," DEP spokesman Robert Geist said.

At 6 p.m. Monday, the DEP and City of Trenton issued a "system wide" water conservation notice for all Trenton Water Works customers, asking them to "limit all water uses, and refrain from any nonessential uses of water to help available water supplies," a new alert said on the city's website.

"Please be aware that although not anticipated recovery to normal operations could take several days, and customer conservation will be necessary until further notice," the Monday evening alert said.

Earlier in the day, officials said the water utility's plant shut down operations at roughly 5 a.m. Monday, Jan. 15, due to elevated turbidites (haze due to particles) and inadequate disinfection of delivered water, Geist said.

The boil advisory includes downtown Trenton, Ewing and Hamilton townships, impacting about 35,000 residents, he said.

The DEP estimates normal water service to be restored by Tuesday evening.

Water quality samples will be collected and tested for chlorine and coliform on Monday, and will be analyzed by the end of the day on Tuesday, according to a Water Supply Emergency Situation Report.

An advisory about the boiling was posted on the city's website Monday afternoon. No phone alerts or notifications were issued to city residents, Trenton Police said.

A second, more detailed advisory was posted on Trenton's website later Monday afternoon.

The Deutzville neighborhood of Hamilton, serviced by Trenton Water Works, was notified of the advisory online, through Hamilton's town website. Ewing also alerted residents on its website.

Trenton Water Works has come under fire recently by the state for failing to provide reliable and safe water to Mercer County residents, after DEP Commissioner Bob Martin sent two letters to Trenton Mayor Eric Jackson's office in October and November.

The city of Trenton did not immediately respond to questions, as the office is closed for the federal holiday.

Editor's Note: The story has been updated with information from Trenton and the state DEP.

Sophie Nieto-Munoz may be reached at snietomunoz@njadvancemedia.com. Follow her at @snietomunoz. Find NJ.com on Facebook.

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