The Wyoming Transportation Department says a single entrance proposed for the 500-unit Teton Meadows Ranch subdivision would be “potentially catastrophic to emergency response.”

Transportation Department district traffic engineer Tory L. Thomas also called a traffic impact analysis the developers prepared “enigmatic and misleading” following his review of the subdivision plans. He made his comments in a letter dated Feb. 22 and addressed to Blair Leist of the Teton County Planning Department.

The letter addresses some of the traffic issues the state agency said will emerge should the county approve a zoning change that would permit a tenfold increase in development potential to allow the subdivision. Proposed by James Reinert for the southern end of South Park, Teton Meadows would have 250 traditional affordable homes, plus another 250 units, all on 288 acres.

The Teton County Planning Commission continues its debate regarding the application today in the Teton County administration building, 200 S. Willow. Its meeting starts at 6 p.m.

Thomas said traffic from South Park Loop Road trying to get to Jackson via U.S. 89 would be held up if additional development occurs in the area.

“The left turning movements from collector side streets such as South Park Road, or any other access, onto a principal arterial such as U.S. 89 will experience poor levels of service,” Thomas said in the letter. “This is not uncommon, as the purpose of an arterial is efficient mainline transport, not necessarily side-street serviceability.”

To overcome that bottleneck, Thomas made several recommendations.

“To enhance side-street level of service, Teton County should analyze and possibly require additional access points to the state highway, effectively distributing ingress/egress,” he said. “In addition, South Park Loop should be improved and widened to allow for a redundant route to U.S. 89, effectively removing/distributing trips to the arterial.”

Circulation within the subdivision and connections with neighboring ones also is poor, Thomas wrote.

“As proposed, the development lacks internal circulation with adjacent developments, a fundamental province of current planning and design,” he wrote. “A single access to the entire 500-lot subdivision is proposed, potentially catastrophic to emergency response if the sole access were to become compromised.”

The state agency also criticized claims that South Park Loop Road’s southern intersection with Highway 89 would be controlled by a stoplight.

“The analysis also claims that the intersection of South Park and U.S. 89 will require signalization by 2013 regardless of the proposed development, yet no signal warrant analysis was completed to substantiate this claim,” the transportation letter said. “The Traffic Impact Analysis completed for this proposed development is enigmatic and misleading, similar to other reports prepared by the consultant.”

Developers said they had no comment on the letter. But South Park Neighbors organizer and spokesman Rich Bloom said WYDOT’s analysis confirms the group’s own traffic numbers.

“It has become increasingly apparent that something is amiss when concerned citizens are able to point out deficiencies in traffic, planning and environmental analysis that somehow escape a professional planning staff,” Bloom said in a statement. “Teton Meadows’ proposed 10 times upzone will push the road over its present carrying capacity, destroying this scenic corridor by forcing the removal of 2,000 mature cottonwoods, and closing an important wildlife migration route identified by Wyoming Game and Fish.”