The ongoing shutdown has left the federal government short in paying its water bills in Washington.

A top DC Water official said the Treasury Department emailed last week to say that it “will only collect and remit” about $10.5 million of the $16.5 million that federal agencies owe the city water and sewer authority for the second quarter of fiscal year 2019.

The email from Treasury’s Bureau of the Fiscal Service blamed the shortfall on the shutdown and the “potential creation of Antideficiency Act violations,” a reference to a law that prohibits federal agencies from spending more than has been appropriated by Congress.

D.C. Water Chairman Tommy Wells pressed the water agency’s top financial official at a public meeting last week to forecast the situation “to the absurd, or the furthest out: How long can we carry the federal government before it creates a fiscal weakness to the enterprise?”

Matthew Brown, the agency’s vice president of finance and procurement, responded that the shortfall would have to be compounded for about a year, reaching roughly $20 million, “before it begins to be a real problem,” according a recording of the meeting.

D.C. Water spokesman Vincent Morris said cutting off service to the White House or other federal buildings is not in the cards.

“We very rarely shut off any customer’s water. It’s a last resort,” Morris said.

The payment issue was first reported by Washington-area public radio station WAMU.

And in this case, “since the Federal government pays in advance, its account is not past due, and DC Water is not contemplating shutting off water to any Federal properties,” the agency said in a statement.

DC Water also said it would work with any federal worker facing hardship during the political impasse. “They are unintended victims in this situation and we are gladly willing to provide anyone affected by the shutdown with a payment plan or other options for paying their bill,” said David L. Gadis, the agency’s chief executive officer.

Treasury officials did not immediately respond to emailed questions about what message the federal government is sending to ordinary water customers with its shortfall or how many millions the federal government is unable to “collect and remit” for water and sewer services elsewhere in the country.

A computerized message at Treasury’s public affairs office said the voice mail “has an extended-absence greeting in place and will not accept new messages.”

Treasury’s email offered a view into the mundane mechanics of the shutdown.

“Typically amounts owed to DC Water would be collected in full from Federal consumers on the 1st business day of the quarter and remitted to DC Water on the 2nd business day,” the Treasury official wrote. “Employees who typically perform this work are currently furloughed.”