John Austin isn't sold on the idea of building a multi-use trail alongside the Merritt Parkway from Greenwich through Stratford.

Austin, who attended the state Department of Transportation's fifth local forum on the proposed trail Tuesday night at Westport Police Department headquarters, said the trail could make it easier for people to break into homes near the Merritt Parkway because motorcyclists likely would have access to the trail. "If you make a trail smooth enough for a bicyclist, how are you going to prevent a motorcyclist from staging a break-in?" he asked.

Austin, a Fairfield resident, also doubted the trail would be heavily used and suggested the parkway's right-of-way, where the trail would be built, might be better suited for a high-speed rail system that links to Metro-North Railroad. "This is a very valuable piece of property. It's worth billions of dollars," he said. "If we build the trail, it's going to be a roadblock to any future use."

But Ray Rauth of Weston, who also attended the Westport hearing, said the proposed trail is "a terrific idea" and that some concerns could be alleviated by investigating the impact of other multi-use trails in Connecticut. He said concerns about safety, security, noise, declining property values and drivers on the Merritt Parkway becoming distracted by trail users are "just concerns that crop up because of unfamiliarity."

Rauth, a member of the Connecticut Bicycle and Pedestrian Advisory Board, which reports to the DOT, said the trail would be near the future home of the Westport Weston Family Y and that parents and kids could ride bikes there. "If anybody's bicycle literate, they could also use it to get to the beach or Sherwood Island State Park," he said. "The idea of having a safe place for families to go, I think is so necessary ... I think it would be used. I think it would be heavily used."

William Britnell, a principal engineer at the DOT, predicted there would be divergent opinions on the potential trail project. "The trail has been a pretty controversial subject. Most people either love it or hate it," he said at the start of Tuesday's hearing.

Top concerns of people at Westport's hearing differed from top concerns at previous hearings in Stamford, Greenwich, New Canaan and Fairfield, Britnell said. "Privacy has been one of the top [concerns] in other towns, and it only got one vote here tonight. The votes were spread around," he said of the views expressed in Westport.

The top concern at Westport's hearing was how the trail would cross the Saugatuck and Aspetuck rivers, followed by whether the trail would be safe at points where it crossed local roads and its impact on the environment and wildlife.

Britnell said river crossings were "not really mentioned in other towns." But, he added, "we weren't crossing rivers" in other communities.

The trail would be from 10 to 12 feet wide and run alongside the entire length of the 37.5-mile Merritt Parkway in Fairfield County. In most places, the trail would be in the middle of the 300-foot-wide right-of-way on the parkway's southern side, though it may have to deviate from the middle, cross onto local roads or switch to the northern right-of-way because of topography or environmental concerns, Britnell said.

The trail would be designed for novice and advanced bicyclists, walkers, joggers, people with disabilities and possibly horse riders.

Britnell said the DOT didn't plan to build bridges or tunnels where the trail would cross local roads. "There are 60 some-odd side streets that the Merritt Parkway crosses ... Most of the crossings we're assuming will be at grade, but we will be looking at each crossing to see if a grade separation makes sense," he said.

Other concerns mentioned at the Westport hearing included the potential for food left on the trail to attract wildlife; noise during construction; whether emergency responders could easily get to the trail; the safety of trail users; loss of trees between the parkway and homes; whether conflicts could arise between different groups using the trail; whether restrooms would be available, and the cost to build and maintain the trail.

The cost to build the trail hasn't been determined, but Britnell said it wouldn't be cheap.

"Thirty-seven miles of anything is going to be expensive. This will be an expensive proposition," he said. The DOT doesn't have the personnel to maintain the trail so an alternative way of emptying trash bins, clearing debris and repaving the trail would have to be found, Britnell added.

Attendees at Tuesday's hearing suggested civic groups could adopt parts of the trail and maintain them.

Benefits of the proposed trail as seen by the DOT and hearing attendees include: Providing a place where families could safely ride bikes; an alternate way for people to commute to work and go from town to town; a different way to experience the Merritt Parkway; a venue for exercise; potential increases in tourism and economic activity; educational signs about the parkway's history and local environments, and an east-west connection to existing north-south trails.

The trail also could provide another access to the Rolnick Observatory on Bayberry Lane in Westport, the Trumbull shopping mall and the Red Barn Restaurant in Westport, attendees said.

Britnell said the DOT is neutral on the idea of building the trail, but was "somewhat resistant" in the past because of the cost, impact on the scenic and historic character of the Merritt Parkway, and questions about how the trail would cross local roads and watercourses.

The feasibility study is being funded through a $1.3 million grant from the National Scenic Byways Program, and the DOT plans to return to the eight communities along the parkway route in the fall or winter with a conceptual design and answers to questions raised at hearings, Britnell said.

Future hearings on the proposed trail are scheduled at 7 p.m. May 14 in the Trumbull Library and 6:30 p.m. May 17 in Norwalk High School. The time and location of the meeting in Stratford hasn't been set.