A double tractor-trailer is something you don't often see in Connecticut or the rest of the Northeast. But in other parts of the country, such as some Western states and I-80 in Ohio and Indiana, they've been in use for years.
Canada, too, has long allowed double full-size trailers in its Western provinces and Quebec. Ontario will launch a pilot program this summer allowing 100 double trailers on certain highways for one year. Canadian trailers are longer than American ones (23 meters vs. 15-16 meters), so a double tractor-trailer on a Canadian freeway is a more impressive sight.
It also takes longer to pass a double. On a rain-slicked road at night, with the spray flying thick and fast off the trailers' roofs, it seemingly takes forever.
What does this have to do with the environment?
Simply this. A double trailer means one less tractor on the road, which means gas consumption and exhaust emissions get cut. Not by half, because the lone tractor needs to expend more energy pulling two loads instead of one, but by one-third.
Which sounds like small savings, but every bit helps.
(Photo: U.S. DOT, Federal Highway Administration)