Like most major cities, Louisville has traffic problems. Local officials have proposed a $2.4 billion solution — build an additional bridge downtown and connect two major highways in Kentucky and Indiana to create an outer beltway.

But before they build the bridge, transportation officials must comply with a federal regulation called "Section 4F" (search) which forbids them from impacting any historical grounds if they have a prudent alternative.

In this case it means highway engineers must build a tunnel to save the historic property of Drumunard Estate (search), which is off limits to the public.

"We are now going to build a $9 million dollar tunnel to save one house," Rep. Anne Northup, R-Ky., said.

Historic preservationists say the Kentucky transportation plan unnecessarily jeopardizes the community's historical value, but federal officials argue that preserving every historic property is costing taxpayers millions.

"We believe a very common sense approach needs to be made to change 4F, to allow us to consider the relative significance of the property that we are going to be impacting," said Federal Highway Administration (search) chief Mary Peters.

Click here to watch a report by Fox News' Jonathan Serrie.