FLINT, Mich. (AP) — Flint residents coping with lead contamination will be cleared to drink unfiltered water again only when outside experts determine it is safe, Michigan Gov. Rick Snyder said Wednesday, acknowledging their mistrust of government officials while saying a full replacement of the city’s pipes is not imminent.

A lawsuit filed earlier in the day by environmental and civil rights groups asked a federal judge to order the prompt replacement of all lead pipes in Flint’s water system at no cost to customers. Snyder did not rule out the eventual replacement of the lead service lines leading from water mains, but said it is a longer-term consideration.

In the meantime, Flint hired a Virginia Tech professor who helped expose the lead problem despite initial skepticism from state regulators to now oversee water testing. Professor Marc Edwards also was appointed by Snyder to a committee that will set in place long-term solutions.

“There absolutely is a trust issue,” Snyder said during a news conference with state and local officials who announced more plans to address the city’s crisis. The Legislature is expected to direct $28 million in additional funding toward Flint on Thursday.

Mayor Karen Weaver said residents should not have to pay for the water “they did not and are not using.” Emergency budget legislation approved Wednesday by a Senate committee includes $3 million to help Flint with unpaid water bills.

“I was glad that the governor said these are just first steps because I’m asking for a staircase,” she said.

Flint residents are currently unable to drink unfiltered tap water, and tests have shown high lead levels in some children’s blood. While under state financial management, the city switched its water source to the Flint River but without controlling corrosion. That caused lead to leech into the water for a year and a half and contributed to the spike in child lead exposure before state and officials fully acknowledged the problem in early October.

It remains unclear how badly the lead service lines were damaged by the river water. While Snyder’s administration has estimated it could cost up to $55 million to repair some 15,000 pipes, he cautioned that more study is needed.

“A lot of work is being done to even understand where the lead services lines fully are,” Snyder said. “The short-term issue is about recoating the pipes (with chemicals) and that will be based on third-party experts saying the water is safe. … It’s a lot of work to take out pipes, to redo all the infrastructure.”

Michigan Department of Environmental Quality Interim Director Keith Creagh said water samples show “things are trending better,” but he stressed the results are not statistically valid.

“Now we need to figure out … is there a protective barrier” being recoated in the pipes by anti-corrosion chemicals, Creagh said. “Yes or no? … We’re not going to guess.”

He said officials also are working to identify neighborhoods with no lead pipes, so those residents can get the all-clear on their water.

The lawsuit filed Wednesday expresses doubt about whether the city can maintain optimal corrosion treatment when it switches to another new water source later this year. It seeks a ruling to force city and state officials to remedy alleged violations of the U.S. Safe Drinking Water Act, including a failure to properly treat the water for corrosion, test it for lead, notify residents of results and accurately report if the correct sample sites are being selected.

“It’s essentially asking the government to do its job,” said Wayne State University assistant law professor Noah Hall. “There doesn’t seem to be any unit or level of government that didn’t screw up here.”

Hall, an environmental attorney, said there is precedent for a federal judge to effectively assume broad authority over a water system. The Detroit water and sewer department was overseen by judges for 35 years.

Nick Schroeck, another Wayne State assistant professor and environmental expert, said the judge might determine that government officials already are doing enough to make the water supply safe again.

The suit was filed by the Natural Resources Defense Council on behalf of citizens, along with the American Civil Liberties Union of Michigan, the Concerned Pastors for Social Action and Melissa Mays, a Flint resident.

At least three other suits have been filed since the crisis was exposed in the fall. Two seek class-action status and financial compensation; another asks a judge to declare that users do not have to pay their water bills.

Snyder also announced Wednesday that a close adviser, Flint native Rich Baird, would run a new state office inFlint. He also convened the first meeting of experts on a new 17-member committee to deal with what he called the “terrible tragedy.”

Later, during a 50-minute town-hall style telephone call with nearly 8,000 listeners, Snyder told a questioner about 200 Flint children with elevated blood-lead levels have been identified. He said more kids need to be tested, though.

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This story has been corrected to reflect the proper name of the Natural Resources Defense Council.

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David Eggert reported from Lansing, Michigan. Follow him at http://twitter.com/DavidEggert00 . His work can be found at http://bigstory.ap.org/author/david-eggert .

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