The U.S. Environmental Protection Agency (EPA) wrote to the State of California on Thursday, warning it that it may be violating federal water quality laws by failing to deal with the homeless crisis and the pollution it causes.

President Trump hinted last week during a fundraising trip to the state that the EPA might be planning to act against California for neglecting the homeless crisis by citing it for violating environmental laws.

A letter from EPA Administrator Andrew Wheeler to California Gov. Gavin Newsom, provided by the Washington Post, indicated:

The EPA is aware of the growing homelessness crisis developing in major California cities, including Los Angeles and San Francisco, and the impact of this crisis on the environment. Indeed, press reports indicate that “piles of human feces” on sidewalks and streets in these cities are becoming all too common. The EPA is concerned about the potential water quality impacts from pathogens and other contaminants from untreated human waste entering nearby waters. San Francisco, Los Angeles, and the state do not appear to be acting with urgency to mitigate the risks to human health and the environment that may result from the homelessness crisis.

The letter also expresses concern about San Francisco’s practice of “routinely discharging more than one billion gallons of combined sewage and stormwater into San Francisco Bay and the Pacific Ocean on an annual basis.”

Wheeler says that the EPA is prepared to step in unless California can assuage its concerns within 30 days.

Earlier this week, the Post notes, the EPA also threatened California with the loss of federal highway funding unless it took steps to address air quality. “California has the worst air quality in the United States,” Wheeler wrote.

On Wednesday, Gov. Newsom launched a state program to put a satellite into orbit to measure climate change.

Joel B. Pollak is Senior Editor-at-Large at Breitbart News. He earned an A.B. in Social Studies and Environmental Science and Public Policy from Harvard College, and a J.D. from Harvard Law School. He is a winner of the 2018 Robert Novak Journalism Alumni Fellowship. He is also the co-author of How Trump Won: The Inside Story of a Revolution, which is available from Regnery. Follow him on Twitter at @joelpollak.