Four years after the start of the Flint water crisis, Michigan state regulators are on the verge of approving some of the strictest rules in the country to reduce the risk of water-based lead poisoning. But local governments warn that the rules are needlessly expensive, likely unconstitutional and won’t necessarily improve public health.

Michigan’s Department of Environmental Quality (MDEQ) drafted the rules, which could officially take effect in the next two weeks. The most ambitious aspect of the regulations would require water utilities to replace all lead service lines (the pipes that connect water mains to buildings) within the next 20 years. Utilities would have to do the work and pay the costs for doing so, even if all or part of the line is privately owned, as most are.

State environmental regulators also want to lower the threshold of lead taken from home water samples that would trigger more scrutiny of a utility’s water system.

“In wake of the Flint water crisis, there has been immense public pressure to update the rules to protect public health,” the department explained when announcing the rule. “Health providers, elected officials and the public at large have become aware that the existing rules and drinking water standards for lead are not health-based standards and not as protective of public health as they should be, especially for vulnerable populations of infants and children.”

Tiffany Brown, an MDEQ spokeswoman, says the new rules address several shortcomings of current testing procedures. The proposal requires utilities to keep track of where lead service lines are in their system; improves water testing to make sure they measure lead exposure in both fixtures and service lines; and guarantees that lead service lines are eventually removed.

“As long as there is lead in the system, there will be a risk of exposure,” she says.

But many of the state’s cities and water utilities oppose the new rules, even if they agree that they want to keep lead out of the state’s drinking water.

“The state is giving the impression that the new rules are more protective of public health, but we don’t necessarily think so,” says Kelly Karll, an engineer with the Southeast Michigan Council of Governments.

Overall, local public health departments in Michigan are more worried about children being exposed to lead from lead paint than from contaminated water, she says, because the kind of contamination that Flint residents faced is rare.

Besides, she says, the new rules don’t even directly address the problem that caused the Flint water crisis. There, the city’s water became contaminated in 2014 after it switched from using water from Detroit’s Lake Huron to the Flint River, in an effort to cut costs. When the city made the switch, though, it did not add chemicals to prevent lead pipes from corroding, which is standard practice in the industry. So the river water stripped the protective coating that had built up over years on lead pipes in the city, which, in turn, lead to high lead levels in many homes.

But Michigan’s new plan doesn’t require cities to conduct a corrosion control study when it switches water sources, Karll notes.

Molly Maciejewski, the city of Ann Arbor’s public works manager, also questions changes in testing criteria for lead in the water. Under federal law, drinking water utilities must take water samples from high-risk homes or buildings every six months. If 10 percent of those samples contain more than 15 parts per billion of lead, the utility must take steps to address it, including the use of anticorrosive chemicals.

The new Michigan rules would change that threshold from 15 parts per billion to 12.

But Maciejewski, who heads the government affairs council for the Michigan chapter of the American Water Works Association, says the federal threshold is a way of testing the effectiveness of a utility’s corrosion control, not a way of determining whether water is safe to drink. (Scientists warn that any amount of lead is dangerous, especially for infants and toddlers.)

“We definitely want to get the lead out, but any changes in the action level should be based on science,” Maciejewski says. MDEQ originally proposed setting the new levels at 10 parts per billion, but then raised the threshold after pushback from legislators. “We’re not sure where 12 parts per billion came from, but it doesn’t appear to be based in science.”

Michigan’s focus on replacing lead service lines could be both illegal and extraordinarily expensive, the opponents say.

The legal problems stem from provisions in the Michigan state constitution that prohibit cities or divisions of the state from using public money for private purposes. By making water utilities pay for lead service line replacements on private property, the MDEQ regulations would force utilities to use public ratepayer money to upgrade private infrastructure. “It’s unconstitutional,” Karll says.

Cities that have successfully replaced their lead service lines, including Lansing and Kalamazoo, actually own the pipes all the way to the building, which allowed them to avoid the legal obstacles.

Replacing all the lead service lines in Michigan would also be very expensive. The state pegs the cost at about $500 million, based partly on the costs of replacing lead service lines in Flint. But a coalition of local governments and water agencies in Michigan estimates that the price would be more like $2 billion. Karll says the state did not take into account complications that can come up when utilities try to replace lead pipes, such as getting legal access to properties and doing restoration work.

Those new costs would lead to higher rates, at a time when utilities are increasingly concerned about the affordability of water.

The state may pitch in some money but it likely won’t cover much. Brown, the MDEQ spokeswoman, says that the agency will soon give out $10 million to help cities with lead service line inventories and replacement. “While this is admittedly a very minor amount compared to the overall cost, it clearly demonstrates our commitment to helping our partners deal with the issues,” she says.

The cities and local governments say that they could save money and replace lead service lines more efficiently if they could replace them at the same time as they replace water mains or dig up roads outside the buildings, rather than being forced to do all the replacements with in 20 years. The state says it will accommodate those plans as long as they are “reasonable.”

A joint committee of the legislature is now considering the rules, but it looks like lawmakers will not change them. Even when the rules are finalized, though, they could be superseded by legislation or challenged in a lawsuit.

But Maciejewski of Ann Arbor says officials in Michigan recognize that the rules will draw a lot of attention, particularly because the U.S. Environmental Protection Agency appears to have pushed off long-awaited revisions to federal lead standards until 2019.

“We know that other states are watching. All eyes,” she says, “are on Michigan.”

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