Transportation Secretary Ray LaHood reminded the nation’s governors and state Secretaries of Transportation, this week, that any money they save on transportation projects paid for with American Recovery and Reinvestment Act dollars must be used for additional transportation projects.

Across the nation, reports are showing that contractor bids to build and repair transportation networks are coming in substantially below the original engineering estimates.

In a letter, Secretary LaHood urged the governors and transportation secretaries to take those cost savings and use the money for additional projects that will put more people to work.

“We will work with you to ensure that your state benefits from your frugality,” LaHood wrote. “Savings you accrue from awarding low bids and from reduced construction costs due to your oversight and project management should remain in your state to be spent on other eligible transportation projects.”

In just seven weeks, the U.S. Department of Transportation (US DOT) approved more than 2,400 requests worth $7.5 billion for highway, road, bridge and airport construction and repairs nationwide. Projects have been approved in every state. US DOT economists estimate that more than 39,000 job-years will be created just from the projects approved so far.