US Metro is losing US$400,000 (NZ$593,000) a day as the federal government shutdown drags on, cutting into its ridership and parking revenue, according to a letter the agency sent to the region's US senators.

The transit agency, which estimates federal workers make up 40 per cent of its rush-hour ridership, says it is suffering steep losses amid the shutdown - the longest in US government history. In the letter, which was tweeted by Senator Mark Warner, Metro General Manager Paul Wiedefeld writes that the agency has suffered daily rail ridership losses averaging 16 per cent; average daily ridership for Metrobus is down 8 per cent.

The losses, he said, could become more acute as the shutdown stretches on because February SmartBenefits - the commuter benefit offered to federal workers to incentivize transit use - will not be distributed for the month if the shutdown stretches beyond Jan. 21.

"Our preliminary analysis estimates that for an average weekday when the federal government is closed, Metro is losing approximately $400,000 in fare and parking revenue," Wiedefeld said in the letter. Wiedefeld said Metro "will take whatever measures [are] necessary to ensure safe operations" amid the shutdown.


"However, if ridership declines continue, in the short term, Metro could consider staffing or service adjustments, such as scaled back use of eight-car trains and extra trains to meet rush-hour demands."

Wiedefeld added that the transit agency could be forced to seek additional funding from the District of Columbia, Maryland and Virginia if it cannot find the money to continue operating the system in the longer term.

Meanwhile, the shutdown means federal grant money the agency is owed is not being disbursed, leaving the agency with $33 million in capital spending that has not been reimbursed. The transit agency will face a $50 million shortfall for January if reimbursements don't come through, Wiedefeld said.

"If the federal shutdown continues for an extended period, Metro will be forced to either turn to its Line of Credit (LOC) to support the Capital program, incurring additional costs, or defer important state-of-good-repair projects, which could undermine our recent reliability gains," Wiedefeld said in the letter.

In a joint statement Thursday night, Warner and other Democratic Senators Tim Kaine, Ben Cardin and Chris Van Hollen said the effects on Metro highlight the need for the shutdown to be ended swiftly.

"At a time when Metro already is undertaking substantial, disruptive projects to improve safety and reliability, President Donald Trump's shutdown is jeopardising the health and stability of the entire Metro system," the senators wrote. "This wasteful, destructive shutdown must come to an end."

Metro declined to elaborate on the letter issued by Wiedefeld, saying the document "speaks for itself."

- Washington Post