ADAMS, Mass. — The proposed trail system at the Greylock Glen is being scaled back to avoid wetlands crossings.

Harry Dodson, trail designer Dodson & Associates, said the Army Corps of Engineers is demanding that there be no impact in wetlands and the recent delineation of where those lands are has rendered the original design too expensive.

The original design would have required more than 100 bridges or other types of crossings to be constructed and cost more than the $3 million available.

"We have suggested that we look at downsizing and reorganizing parts of the trail," Dodson told the Greylock Glen Advisory Committee last week.

Dodson presented two ideas to the committee for a phased implementation — one option is 2.5 miles with a reduced amount of the largest trails and the other of 1 mile.

Eventually planners hope a full trail system of 32 miles will be built.

"Our goal is to eliminate wetland and stream crossings," Dodson said of the newest ideas.

However, the committee members said they couldn't make a recommendation without knowing the full impact of each trail design. For example, neither options would be long enough for Nordic ski races. The committee hopes to hear from the different types of trail users before settling on a final design.

"It's better wider and longer for whatever may happen," committee member George Haddad said. "You want the maximum width you can get."

The trails are set to incorporate four types of trails. Class 1 trails are 10 feet wide and can accommodate such uses as ski races, horse and buggy rides. Class 2 trails are 6 feet wide and accommodate cross-country skiing as well but races would be cramped. The system would also include snowmobile and hiking trails.

With length of the trail being the apparent holdup for the committee to make a final decision, members told Dodson to continue with the 2.5-mile option but look for ways to extend it. Dodson said there are opportunities to tweak the trail to get the extra half mile or so they would need for a 5-kilometer Nordic ski trail.

Permitting, involving the Army Corps of Engineers, the town's Conservation Commission and the state Department of Environmental Protection has required additional consultants and studies over the last three years.

The trails will be constructed in two phases. The first phase would cost $2 million and the second $1 million. The designers are hoping to finalize the plan so that the entire construction can be permitted. The state money for the trail system will not be in place until fiscal 2015.