NEWARK — What else could go wrong?

The city on Tuesday had to stop giving out free bottles of water to people affected by lead contamination after learning that the water was past its expiration date.

Although the water is not unsafe to drink, officials had to order replacements.

It was the latest snafu in a years-long crisis involving thousands of households in the state's largest city.

The city began giving out cases of water on Monday after testing showed that the filters that the city has been distributing to homes might not be effective. Lead levels exceeded the safety standards in two of the three homes that were tested. More testing will be done.

Newark has distributed more than 30,000 filters since last year to homes with lead service lines the connect buildings to water mains. The federal Environmental Protection Agency told the city that the filters were effective.

The source water is not contaminated with lead but the chemicals used to treat the water had been causing the lead in the pipes to leach into the water. The problem was discovered in 2017.

The water treatment facility has since changed the chemicals but officials are now worried that reduced use of tap water in the affected households may prevent the anti-corrosion treatment from working because the water has to be flushed from the pipes.

The city distributed 20,000 cases of water on Monday. The state ordered 20,000 replacement cases and another 50,000 cases for Tuesday.

The Natural Resources Defense Council is suing the city in U.S. District Court, arguing that the city has failed to adequately monitor lead levels and that officials should go instruct every resident in person on how to properly install the filters.

Federal lawmakers from New Jersey have asked the EPA to provide more federal resources to help Newark.

In a letter Tuesday to EPA Regional Administrator Peter Lopez, the lawmakers asked the EPA to help distribute bottled water to residents.

"Given your commitment to safeguard the residents of Newark and to advance the goal of protecting public health and the environment, we respectfully request your immediate assistance in identifying any and all options to provide not only technical assistance, but on the ground support and resources in Newark until further analysis is concluded and a solution to these new concerns is implemented," according to the letter signed by U.S. Sens. Cory Booker and Bob Menendez and U.S. Reps. Albio Sires and Donald Payne Jr.

The Associated Press contributed to this report.