Updated

The American Civil Liberties Union of Michigan sued the state education department and Flint schools on Tuesday, saying they had violated federal education laws by exposing students to high levels of lead in their drinking water.

The children must be screened for lead exposure and adequate special education funding must be provided to serve a potentially growing need for services, according to the suit, which also was filed by the Education Law Center and private attorneys.

The lawsuit calls for the defendants - Michigan Department of Education, Genesee County Intermediate School District and Flint Community Schools - to check for elevated blood levels in all children who now, or may, attend Flint schools to determine their eligibility for special education services under the U.S. Individuals with Disabilities Education Act.

The state education department and Flint schools declined to comment on the lawsuit.

Flint, a predominantly black city of 100,000, was under the control of a state-appointed emergency manager when it switched its water source from Lake Huron to the Flint River in April 2014. The more corrosive river water caused lead to leach from city pipes and into the drinking water.

Lead can cause mental and behavioral problems in children and Flint's water problem has led to dozens of other lawsuits in various courts.

The ACLU of Michigan's class action was filed on behalf of nearly 30,000 Flint children ranging in age from birth to 19 who could be exposed to lead at home and in school since the water crisis began in April 2014.

"This lawsuit exposes what has gone wrong, including a dysfunctional funding structure, and demands clear and urgent remedies to make it right," said Kary Moss, ACLU of Michigan's executive director.

The defendants are failing to provide sufficient resources for current needs and not preparing for a likely increase in cases due to the widespread exposure to lead, the lawsuit said.

The budget is inadequate to serve even those 900 of 5,400 students in Flint Community Schools now eligible for special education and related services, the lawsuit said.

The city switched its water source back to Lake Huron in October 2015 after tests found high levels of lead in blood samples taken from children but the drinking water has not returned fully to normal. Flint has been replacing lead pipes running to homes and state officials say the water is safe to drink if properly filtered.

(Reporting by David Bailey in Minneapolis; Editing by Bill Trott)