Boy,do we remember "The Big Dig" here in Massachusetts! While this fiasco was unfolding Barney Fag (sorry:Barney Frank) was the Congresscreature representing that part of the state. While commenting once on the project...critising it in fact...he made the only statement that I've ever agreed with.
He said: "It would be cheaper to raise the city than it would be to lower the Expressway".
The "city" being Boston,the "Expressway" being The Southeast Expressway,a major artery through Boston.
Do you know what the speed limit was on the old Distressway? When I traveled north on 93 through the tunnel in 2015, it was THIRTY-FIVE mph in the south part and FORTY-FIVE in the north part. I slogged my way through the facility (going a little faster than that, of course) and ended up wondering why they ever did it.
(The I-90 Extension tunnels to the airport, which I drove through in 2007, were 50 or 55 mph, if I remember correctly.)