Ask anyone who spends any time at all driving on Indiana interstates how many billboards they’ve seen, and they’re likely to reply, “Too many to count.”

Unfortunately, that also seems to be the case for the Indiana Department of Transportation. The Federal Highway Administration has threatened to withhold $90 million from the state because an inspection “cast significant doubt” on Indiana’s ability to control outdoor advertising.

The federal government reviewed billboards along 577 miles of controlled highways in the state and found billboards in areas prohibited by federal law, permits for blank billboards, billboards placed in public right of way, size-standard violations, the use of parked semi-tractor trailers as billboards and more violations. A provision in the Highway Beautification Act sets outdoor advertising standards along controlled highways.

It’s not the state’s first warning. In 1995, the federal government threatened to withhold funding if INDOT did not remove billboards erected under a law that had been repealed. The 2008 report found that some billboards might have been placed as recently as 2002 under that same outdated law.

There’s no one group to blame for the billboard bloat, an INDOT official told the Gary Post-Tribune.

“There’s no smoking gun, no one person, no one party, no one agency, no one group of outdoor advertisers,” said Robert Demuth, central office permit manager for INDOT.

Actually, there is an agency responsible. It’s INDOT, which clearly has had plenty of reminders of its responsibility in keeping an active inventory of billboards.

Demuth said his challenge now is coming up with $2.5 million to update the inventory.

Granted, that’s a steep price. But the loss of $90 million in federal dollars is much greater, and a state that leased its toll road for $3.8 billion ought to be able to come up with the money to put it in compliance with federal law.