Using a federal loan to finance $2 billion of the cost of the Tappan Zee Bridge could delay construction work significantly, warns trade journal Project Finance today. Trading time for a low interest rate might save money, but it puts the lie to the Cuomo administration’s claim that adding transit would unacceptably slow the Tappan Zee project.

“Waiting for TIFIA debt to close could delay the Tappan Zee project,” wrote Project Finance, referring to the federal loan program the state applied to. The last TIFIA deal, for a rail line in Denver, just closed in December 2011, though the application was submitted in fiscal year 2010. None of the fiscal year 2011 TIFIA applicants have received a loan yet.

TIFIA loans are about as cheap as borrowing gets and worth the wait. When it comes to financing, the Cuomo administration recognizes that it’s better to do the project well than to do the project instantly. But Cuomo is using much different logic when it comes to transit.

This January, state DOT Commissioner Joan McDonald told a Hudson Valley audience that adding transit to the Tappan Zee would push back construction by at least two years. Without transit, she said, construction would be able to begin in 2012.

With a bridge meant to last a century, it’s worth waiting a little bit longer to build a span that includes transit. Without transit, a new Tappan Zee Bridge will just promote sprawl while doing nothing to curb congestion, reduce environmental damage, or help residents get around affordably.