Republican and Democratic negotiators in the House earlier today killed language in a $1.1 trillion fiscal year 2016 omnibus spending bill that would have added 10 feet to the length of each twin-trailer operating on the country's federal-aid highways. The move dealt a huge setback to commercial interests, which saw the provision as a safe and sensible way to improve motor carrier productivity.

At the same time, legislative drafters effectively shut down the Obama Administration's proposal ordering commercial drivers required to be off-duty for 34 hours within a typical workweek to take two consecutive days of rest between 1 a.m. and 5 a.m., and to limit those extended rests to just once a week. The trucking industry claimed that the language—included in the agency's 2013 driver "hours of service" rules—were not supported by sound science, would cut into fleet productivity, and would force drivers off the road during hours of sparse road congestion only to push more traffic into riskier daytime hours, as drivers would have to share the roads with millions of rush-hour commuters.

Lawmakers required the Federal Motor Carrier Safety Administration (FMCSA), the subagency of the Department of Transportation that drafted the rules, to demonstrate that the controversial language would result in "statistically significant improvement" in all outcomes of driver health, safety, and performance as compared with drivers operating prior to July 1, 2013, the date the rules took effect. Congress had earlier frozen FMCSA's implementation of the provision.

The conferees' move to strip out the longer twin-trailer language represents a big victory for highway-safety advocates, who argued that adding the equivalent of 5 feet to the length of each 28-foot trailer would jeopardize a driver's ability to safely merge onto oncoming highway traffic and to navigate on- and off-ramps. The U.S. road infrastructure was not built to accommodate twin-trailers that are each 33 feet long, according to safety groups.

The House and Senate appropriations committees had approved the so-called "longer truck" language in their respective versions of the Departments of Transportation and Housing and Urban Development FY '16 budget appropriations.

Today's action, combined with an earlier decision by lawmakers to exclude language in the recently signed federal transport-funding bill that would have raised the gross vehicle weight limit—the sum of tractor, trailer, and cargo—on federal aid highways to 91,000 pounds from 80,000 pounds, means that federal truck size and weight limits will remain at levels last changed in 1982. Various states allow for heavier and longer commercial vehicles to operate within their borders.

Supporters of the longer-truck measure said the extended trailers come with similarly longer wheelbases, which would improve stability and performance. They said the longer trailers would not add any more weight to the vehicle, and would reduce the number of trucks needed on the road by allowing shippers to load more lightweight, high-cube goods in each trailer. Adding five feet to each trailer would eliminate 6.6 million truck trips annually, prevent 912 crashes, cut fuel consumption by 204 million gallons annually, and increase fleet productivity by up to 18 percent, supporters said.

The explosive growth of digital commerce over the next 10 years will result in a 40-percent increase in less-than-truckload (LTL) shipments moving in 28-foot twin trailers, backers of the longer-truck language contend. The increase in cubic capacity would be critical, because most orders are lightweight shipments that cube out before they weigh out.

In a statement, the Coalition for Efficient and Responsible Trucking, whose core membership is LTL carriers, said it was "unfortunate and disappointing that political scare tactics won the day over sound policy. In rejecting a modest extension in the length of twin-trailers, Congress missed an opportunity to bring long-overdue efficiencies to freight trucking that would have produced tangible safety, economic, and environmental benefits at a time when so many roads and bridges have fallen into disrepair after years of neglect."

The American Trucking Associations (ATA), which mostly represents large fleets, echoed those comments, saying Congress "allowed itself to be cowed by fear-mongering tactics of antitruck lobbyists." ATA, for its part, found itself in a politically uncomfortable positions because it endorsed a provision that 15 of the nation's largest truckload carriers, and key ATA members, had gone on record opposing as potentially unsafe and harming the competitive positions of smaller truckload carriers.