Their soil is seeped with lead, but the smelting facilities that caused the problem are still operating
Officials said lead levels have dropped in Flint's water, but an inconclusive federal investigation has residents on edge.
A lifetime of diminished earnings, welfare dependency and criminal justice costs will add up.
Speaking in Flint, Michigan, the president also urged parents to make sure their children were tested for lead poisoning.
The president makes a visit to Flint on Wednesday, a city that has become synonymous with failed government and America's crumbling infrastructure.
The suit alleges that the federal agency was negligent in protecting the public from lead-contaminated water, citing agency experts who warned of a problem as early as February 2015.
The action, says the governor, is to help restore public trust in the city's drinking water supply, which — if properly filtered — is once again safe to drink, according to state officials.
Two days of Capitol Hill hearings about Flint, Michigan's contaminated water were dominated by partisan fingerpointing.
Newark's mayor Ras Baraka said austerity, small government, regressive tax reforms, and failure to invest in infrastructure is putting children in communities of color in harm's way.
On the same day that tests revealed half of Newark, New Jersey's schools had elevated levels of lead in drinking water, Gov. Christie called lead contamination an "over-dramatized issue."
The manufacturer of the filters recommends replacing them every six months, at least — but images obtained by VICE News show some filters date as far back as 2012.