One year after President Barack Obama declared a federal emergency in Flint , Michigan, over the lead poisoning crisis, experts say the citys water system has significantly improved but residents still cant drink the water from their taps, and theres no clear end in sight.

On Wednesday, researchers and public officials hosted a town hall meeting in Flint to share the latest water quality data, following a private U.S. Environmental Protection Agency summit in Chicago the previous day. They focused on progress: lead levels in water samples are easily below the threshold to comply with the federal safe drinking water standard, and have been for several rounds of testing.

Other issues with water quality have improved, officials said, citing the ongoing replacement of lead pipe service lines and maintenance of chlorine residuals, a disinfectant used to kill bacteria and other pathogens.

The citys lead pipes were corroded by Flint River water, which caused leaching and the subsequent contamination of the water supply, resulting in an ongoing public health crisis. City, state and federal groups have banded together to respond to the immediate crisis, fund long-term health and education initiatives, and eventually overhaul the citys water system.

However, residents still need to use filtered or bottled water with no set end date and were warned that the water system wouldnt be completely fixed for years.

Our water is not safe until all of the lead in all of our plumbing is gone, said Mona Hanna-Attisha, the pediatrician whose research showing increased lead levels in Flint children brought attention to the crisis.

The citys treatment plant needs more than $100 million to be up and running by late 2019 or early 2020.

An ambitious project to replace lead service lines is underway, but only a small percentage has been completed since March, officials have replaced the lines at 780 homes, of an estimated 20,000, said retired National Guard Brigadier General Michael McDaniel, who heads Flints Fast Action and Sustainability Team.

McDaniel said they plan to finish almost all construction by the end of 2019, but they still dont have all the funding needed to finish the project. Flints replacement efforts could be a model for other cities, he said.

No other city has replaced lead service lines at this rate, he said. We will be like we were once in the 1950s, we will be at the forefront again.

Even though lead levels meet federal standards, Hanna-Attisha said theres a need for caution because the major infrastructure work to replace lead service lines causes disruptions that can increase the risk of lead in the water.

Flints crisis thrust lead poisoning into the national spotlight, bringing attention to other cities dealing with aging lead plumbing and paint. In December, a Reuters report found nearly 3,000 areas around the country that had recent lead poisoning rates at least double those in Flint at the peak of the crisis. Any amount of lead is dangerous, and is a particular concern for young children, for whom lead exposure can cause developmental delays.

Hanna-Attisha said the fact that Flint is not alone when it comes to lead poisoning underscores the failure of federal regulations.

The Lead and Copper Rule is weak nationally, she said. Children are drinking lead in their water everywhere nothing like what happened in Flint but we know that the rules in the book are not strong enough. So until the lead is gone from all of our plumbing, people need to be using filters.