By Brad Kutner

WASHINGTON (CN) – Two days after threatening to pull highway funding from California over “chronic” smog, the Trump administration on Thursday said the Golden State is also falling short of federal water-quality standards, due in part to a “homelessness crisis.”

Environmental Protection Agency Administrator Andrew Wheeler outlined the agency’s concerns, including “piles of human feces” on sidewalks, in a letter sent Thursday to Governor Gavin Newsom.

“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,” the letter states. “The EPA is concerned about the potential water quality impacts from pathogens and other contaminants from untreated human waste entering nearby waters.”

In a statement accompanying the letter, Wheeler said California “needs to fulfill its obligation to protect its water bodies and, more importantly, public health.”

“It should take this letter as notice that EPA is going to insist that it meets its environmental obligations,” he said. “If California does not step up to its delegated responsibilities, then EPA will be forced to take action.”

The agency said California has 30 days to issue a response describing how it will address the water-quality concerns.

The letter is the latest development in an escalating feud between the Trump administration and the Golden State.

On Tuesday, the EPA threatened to withhold highway funding and other federal grants from California over its “chronic air quality problems.” Newsom called the move “pure retaliation,” after the state sued the Trump administration over California’s longstanding right to set emissions rules that are stricter than the federal government’s.

Speaking on a call with reporters Thursday, an EPA official who spoke on the condition of anonymity said the agency had received multiple complaints from state-level overseers that found problems related to run-off systems used during rain storms. Those systems, which were referred to as “storage treatment boxes,” are not large enough to handle waste during heavy storms, according to the official.

“They have significant problems by being a large state, but because of their size they should be able to take care of them,” the official said.

But the official stressed that Thursday’s move was an oversight letter and not an enforcement action, which would involve more authority to punish the state.

“The EPA stands ready to assist California and CalEPA to protect the health and environment of Californians,” the letter states. “However it is time for the state to act decisively under its authorities to address the problems identified in this letter.”

Nathan Click, chief spokesman for Governor Newsom, pushed back on Wheeler’s claims and instead said the letter was a move to “weaponize” a government agency to attack President Donald Trump’s political opponents.

“This is not about clean air, clean water or helping our state with homelessness. This is political retribution against California, plain and simple,” said Click in an email.

Newsom’s chief of staff, Ann O’Leary, said Trump’s “bullying tactics don’t scare us.”

“But they don’t fool us either: you do NOT care about our homeless, our clean air, our clean water….it’s all a big game of retaliation,” she tweeted.