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Here we go again: Federal agencies on Friday started to prepare for a possible government shutdown beginning Oct. 1, the end of the fiscal year.

Though congressional leaders are working on a 10-week stopgap measure to continue funding the federal government, squabbles over whether that bill should include relief aid to Flint, Michigan, have stalled the process. Thus, "at this time, prudent management requires that the government plan for the possibility of a lapse and OMB is working with agencies to take appropriate action," an Office of Management and Budget official told The Hill.

The last time the government shut down because of a funding gap was in 2013, when nonessential employees were sent home for more than two weeks. Contrary to the suggestion of the term "shutdown," only about 20 percent of federal employees are considered nonessential, meaning roughly eight in 10 — more than 3 million people — will keep working as usual should a shutdown occur.