The mayor of Flint, Mich., said Tuesday that the city is a year ahead of schedule in addressing a court-mandated order to deal with lead in service lines.

Flint Mayor Karen Weaver (D) said during a news conference that the city has investigated 18,000 pipes and has replaced 7,700, The Associated Press reported.

She also said that there are between 10,000 and 12,000 more pipes to check, but that officials have dealt with those deemed the highest priority.

ADVERTISEMENT

Weaver cautioned residents to keep drinking bottled or filtered water until all the work is done and tests are completed.

"Getting the poison out — that was my first priority," Weaver said, according to AP.

The Natural Resources Defense Council (NRDC), one of the groups that sued over the lead issue, said Tuesday that the mayor had overstated the city's success.

The group argued that the city hasn't prioritized homes most likely to have lead and galvanized steel pipes, and that thousands of the service lines that were replaced were copper.

"The city has announced it has dug 18,000 holes in the city of Flint, but it has not replaced all the lead and galvanized pipes," NRDC attorney Sarah Tallman told the AP. "The city is in violation of the ... settlement."

The Flint water crisis began in 2014 when the drinking water source for the city was changed from Lake Huron to Flint River, resulting in dangerous toxicity levels.