With operating cash running out quickly, trucks, mail-processing centers, and mail delivery could come to a halt by this time next year, Donahoe said.
"Failure to act could be catastrophic," Donahoe told members of the Senate Homeland Security and Governmental Affairs Committee, which oversees the postal service.
The new proposals reflect heightened desperation at an agency that has been on the decline for years. The rise of e-mail has dramatically curbed demand for old-fashioned letters, while competitive delivery companies have put the squeeze on the post office's business model. Last year, the post office delivered 171 billion pieces of mail, down 20 percent from just four years earlier. Volume is on track to fall an additional 2 percent this year.
Donahoe put the blame for the current crisis on federal laws and labor agreements that he said unduly restricted his agency's ability to adapt and promise more than the postal service can deliver. Labor costs amount to 80 percent of the postal service's expenses, and current contracts contain a no-layoff provision. Changes to the frequency of service or delivery areas require federal legislation.
The postmaster's request arrived just as lawmakers returned from a summer break and appeared prepared to pick up where they left off - in a fierce partisan battle over government spending and job creation. The post office crisis is likely to get thrown into the mix.
Both Democrats and Republicans are quick to express their support for postal services, but even the short-term measures under discussion are likely to find opposition.