JACKSON, Miss. — A boil-water notice was lifted Thursday in Mississippi's capital city after nearly seven weeks, Gov. Tate Reeves and Jackson officials said.

"We have restored clean water," Reeves said during a news conference.

But a state health department official, Jim Craig, said concerns remain about copper and lead levels in the Jackson water. Craig said people should continue to avoid using city water to prepare baby formula.

Emergency repairs are still underway after problems at Jackson's main water treatment plant caused most customers to lose service for several days in late August and early September.

Problems started days after torrential rain fell in central Mississippi, altering the quality of the raw water entering Jackson's treatment plants. That slowed the treatment process, depleted supplies in water tanks and caused a precipitous drop in pressure.

When water pressure drops, there's a possibility that untreated groundwater can enter the water system through cracked pipes, so customers are told to boil water to kill potentially harmful bacteria.

But even before the rainfall, officials said some water pumps had failed and a treatment plant was using backup pumps. Jackson had already been under a boil-water notice for a month because the state health department had found cloudy water that could make people ill.

The National Guard and volunteer groups have distributed millions of bottles of drinking water in Jackson since late August.

Jackson is the largest city in one of the poorest states in the U.S. The city has a shrinking tax base that resulted from white flight, which began about a decade after public schools were integrated in 1970. Jackson's population is more than 80% Black, and about 25% of its residents live in poverty.

Like many American cities, Jackson struggles with aging infrastructure with water lines that crack or collapse. Mayor Chokwe Antar Lumumba, a Democrat in a Republican-led state, said the city's water problems come from decades of deferred maintenance.

Some equipment froze at Jackson's main water treatment plant during a cold snap in early 2020, leaving thousands of customers with dangerously low water pressure or no water at all. The National Guard helped distribute drinking water. People gathered water in buckets to flush toilets. Similar problems happened on a smaller scale earlier this year.

Jackson frequently has boil-water notices because of loss of pressure or other problems that can contaminate the water. Some of the mandates are in place for only a few days, while others last weeks. Some only affect specific neighborhoods, usually because of broken pipes in the area. Others affect all customers on the water system.