By KATHARINE WEBSTER, InDepthNH.org

Advocates for the Derry Rail Trail won a significant victory Monday when U.S. District Court Judge Paul Barbadoro ordered the state not to do anything that would prevent extending the rail trail under a six-lane road that will connect a new Interstate 93 exit to north Derry.

Barbadoro said in his injunction that the state Department of Transportation (DOT) failed to conduct a required analysis on which of three possible rail trail routes would cause the least harm to the Manchester & Lawrence Railroad Historic District, which is near the new exit, 4A.

“I enjoin the defendants from performing construction in the immediate proximity of the Historic District that would in any way foreclose or substantially hinder the completion of the underpass alternative” for the rail trail, Barbadoro wrote.

The Department of Transportation’s 2020 plan for the rail trail, approved by the Federal Highway Administration as part of the Exit 4A project, included a tunnel and 900 feet of paved trail beneath the new Folsom Road. The tunnel would bring the rail trail directly along the historic Manchester & Lawrence Railroad right-of-way.

Once the Exit 4A-related construction is complete, Derry and Londonderry plan to complete and connect their rail trails along the historic rail corridor, which stretches from Salem to Manchester.

But in 2024, the state decided to reroute the Folsom Road crossing to save money. One proposed route would take walkers and cyclists up a steep grade to a crosswalk and stoplight on the six-lane road; the other would send cyclists and walkers in a “spaghetti loop” outside the historic district to pass under a bridge.

The Committee to Save the Derry Rail Trail Tunnel and the Rails to Trails Conservancy, a national nonprofit, sued to block the changes, arguing that either alternative route would significantly alter the historic rail corridor, which was carved through granite by Irish laborers using hand tools and blasting powder.

“This is an important turning point,” Dave Topham, a member of the Committee to Save the Derry Rail Trail Tunnel and president of the New Hampshire Rail Trails Coalition, said in a statement. “This has caused unnecessary delays and expenditures that could have been avoided if the agency had taken the time to engage with tunnel supporters.”

Barbadoro did not rule on the merits of the claim that the underpass is the best of the three alternatives, but his 33-page injunction found that the state never analyzed the impact of the alternative routes, which is mandatory for any project using federal highway funds.

The U.S. secretary of transportation – sued in this case under the names of the administrators who greenlighted the state’s changes – “may select ‘only the alternative that causes the least overall harm in light of the statute’s preservation purpose,’” Barbadoro wrote.

The state had argued that it could save $770,000 by pursuing the alternative routes. Barbadoro noted that was 2.3 percent of the total cost of the one-mile segment of the Exit 4A project affecting the historic district – not the kind of “substantial” cost savings that could justify greater harm to a historic resource, according to prior court rulings.

The office of state Transportation Commissioner William Cass did not return a message asking whether the state would appeal Barbadoro’s ruling.

Andrea Ferster, legal counsel for the Rails to Trails Conservancy, said the judge’s findings indicate an uphill battle for the state if it persists in pursuing an alternative to the underpass.

“An underpass makes financial sense, it makes sense for the trail, and it makes sense for maintaining the continuity of this historical railroad corridor,” Ferster said Tuesday.

She also said Barbadoro’s ruling marks the first court decision applying the law that protects natural and historic resources to a rail trail. The potential to set that precedent was why the national group joined the lawsuit, she said.

Bob Spiegelman, a member of the Committee to Save the Derry Rail Trail Tunnel, said that although the lawsuit and the ruling did not address safety concerns, he and other rail trail users were worried about both alternative designs.

One would require cyclists and pedestrians – including families with small children on bicycles, tricycles, scooters, skateboards and rollerblades – to cross a six-lane road that the state estimates will carry 40,000 cars a day between Derry’s commercial district and I-93.

Even with a stoplight, “It’s an avoidable bad accident waiting to happen, in my mind,” Spiegelman said.

The other, “spaghetti loop” route includes sharp turns on a steep path, another invitation for inexperienced riders to lose control going downhill and get hurt, he said.

“I’m concerned about a 180-degree turn on a 5 percent grade … and the path was not designed wide enough to do that,” he said. “It’s just a terrible design.”