The Illinois attorney general has filed a lawsuit against Trump Tower in Chicago, alleging that it is taking in and releasing millions of gallons of water into the Chicago River without having conducted required studies on pollution or the impact on fish.

Attorney General Lisa Madigan said she filed the lawsuit in Cook County Circuit Court. She said that the building takes in almost 20 million gallons of water per day from the river to cool the property’s heating and ventilation systems, and that heated water is later discarded into the river.

Madigan’s office also said that federal law requires “extensive studies of Chicago River fish populations and the impact of the building’s water intake system” and that the property failed to submit study results to the Illinois Environmental Protection Agency in 2013.

Trump Tower’s National Pollutant Discharge Elimination System permit expired on Aug. 31, 2017.

“Trump Tower continues to take millions of gallons of water from the Chicago River every day without a permit and without any regard to how it may be impacting the river’s ecosystem,” Madigan said in a news release. “I filed my lawsuit to make sure Trump Tower cannot continue violating the law.”

Learn more at NBC News.