The Government Printing Office told Congress last week: Pay up or risk crippling the GPO’s infrastructure.

For two years, Congress has shortchanged the agency on the cost of printing its official reports and documents, postponing the payment for times when the budget isn’t so tight.

But last week, Public Printer Robert Tapella urged the House Appropriations Subcommittee on the Legislative Branch to make it all up in the fiscal 2009 appropriations bill. The shortfall could reach as much as $8.2 million by the end of fiscal 2008.

It’s a small portion of the tens of millions in Congressional printing costs each year — 2007 totaled $97 million — but Tapella said the agency is forced to hold off on other investments in order to cover the extra cost.

Tapella stressed that it is hard to predict the short-term effects of the delayed payments, but he also testified that a worst-case scenario would be a breakdown of the agency itself.

“GPO will cease to function,” he said, adding that the GPO has been at the brink before, albeit for different reasons. “In February of 2003, we did not have enough cash to pay our employees. I don’t want to be in that situation again,” he said.

After years of running deficits, GPO has been in the black for four consecutive years. Officials credit the turnaround to its transition from a traditional printing plant to a digital agency.

This year, the agency pulled in a net income of almost $88 million, thanks mostly to its production of electronic passports for the State Department. But most of that money is already earmarked for upgrades to the passport itself and a planned passport production facility outside the city.

That leaves its other functions on a tighter budget. The agency is on the brink of completing its digital “backbone,” but officials are worried that the unpaid Congressional bills could delay plans.

The Federal Digital System will be the core, storing and making available digital versions of federal documents. That system is set for an initial release by the end of this fiscal year.

At last week’s hearing, Tapella focused on the funding needed for another part of the overall structure called Oracle, a system that keeps track of printing requests and their movements through the system.

So far, the GPO hasn’t asked Congress to pay for that venture, Tapella said. But if lawmakers fail to catch up on their printing bill, the agency may have to dip into the money used to develop Oracle.

Subcommittee Chairwoman Debbie Wasserman Schultz (D-Fla.) voiced her support, pointing out that Members tend to delay on the GPO bills to pay for other priorities that have a more obvious and immediate human effect.

“While it’s not people … it does have a significant impact,” she said. “It could be people at some point.”