Heavily loaded trucks should not be wending their way through downtown Bangor. But, because of federal rules and the desire to move as much freight as quickly and cheaply as possible, they are. The vast majority of them make it through the city just fine, so the overturning of a truck full of trash last week does not signal a trend. There is still good reason, however, to continue to work to get the trucks back on the highway where they belong.

Trucks weighing more than 80,000 pounds are prohibited from traveling on Maine’s interstate highways, including I-95 and I-395. They are not barred from state roads, including those that crisscross Bangor.

There are two ways to solve this problem. One is to lower the weight limits on state roads to 80,000 pounds. This would increase transportation costs and truck traffic. An empty truck weighs 40,000 pounds, so restricting the total weight to 80,000 pounds, rather than the current 100,000 pounds, would reduce the payload by one-third. To haul the same tonnage, a company would have to put more trucks on the road, increasing costs and traffic.

There is no indication that lower weight limits would result in fewer accidents like the one that occurred on Summer Street in Bangor last week. According to the Maine Department of Transportation, accidents involving tractor-trailer trucks are already far less frequent in municipal areas than in rural areas.

There is plenty of evidence that rural, two-lane roads are more dangerous than interstate highways, which are straighter and separate traffic bound in opposite directions. A study, conducted by Wilbur Smith Associates, an international infrastructure consulting firm with an office in Portland, found that the accident rate, per 100 million vehicle miles traveled, was more than four times higher on two-lane roads than on the Maine Turnpike between 2000 and 2003.

The fatal crash rate on “diversion routes,” the largely two-lane undivided highways heavy trucks are now forced to travel, was 10 times higher than the Maine Turnpike and interstate routes, based on miles traveled.

This leads to solution No. 2: increase the weight limit on Maine’s interstate highways to 100,000 pounds, something the state’s congressional delegation has been trying to accomplish for years.

One sensible suggestion is a three-year pilot program. If there are fewer crashes, the higher weight limit would remain in place. If not, the 80,000-pound limit would be back in force. This approach should finally put to the test the idea that raising the weight limit is unsafe while it allows Maine to be competitive with neighboring states and Canadian provinces that all have higher weight limits.

Allowing Maine to follow the same rules as all its neighbors for three years while assessing safety data to allay concerns is a prudent approach worthy of broad support.