Evaluation of Alternatives

After holding both local and regional concerns meetings, an exhaustive list of alternatives was developed and examined by a study committee comprised of the City, Central Vermont Regional Transportation Agency Committee (CVRPC) and adjacent landowner representatives. Due to the large number of commercial and residential driveways in close proximity to the intersection, special consideration was taken as part of the design improvement alternatives. Once a list of alternatives was created the committee then decided on the 3 most feasible alternatives.

Alternative Evaluation Matrix

Costs & Features
(Optimized Signal Timings)
(Protected + Permitted Phasing)
(One Lane)
Preliminary Cost Estimate
Maintenance and Operational Costs
$1,150 / year (signal related) $2,500 / year (signal related) Slightly higher than existing plowing costs due to additional turning lanes. $0 / year (signal related) Moderately higher than existing snow plowing costs, use of loader may be required to remove snow.
Accident Costs
$316,300 / year $241,700 / year $178,200 / year
User Delay (2015 p.m. Peak Hour)
4,976 vehicle minutes / hour (Signal 97)
11,857 vehicle minutes / hour (Signal 97)
1,428 vehicle minutes / hour (SIDRA)
1,222 vehicle minutes / hour (RODEL)
Energy Consumption
26.4 gallons / hour* (signalized movements only)
142.3 gallons / hour
49.4 gallons / hour
Air Pollution (2015 p.m. Peak Hour)
26.7 kilogram CO Em / hour (signalized movements only)
301.2 kilogram CO Em / hour
34.2 kilogram CO Em / hour
No intersection lighting exists
Two new pole mounted metal halide fixtures
Three new metal halide fixtures mounted on free standing poles
Existing pavement area = 73,400 square feet
New pavement area = 68,000 square feet
New pavement area = 64,250 square feet
Total Disturbance
0 Acres
2.27 Acres
2.23 Acres
*Notice: Energy Consumption and Air Pollution estimates for the do-nothing alternative include signalized movements only. Vehicles using the eastbound right-turn lane on US Route 2 and using the crossover area between US Route 2 and US 302 are not included.
Project Decision
A 5-leg roundabout was chosen by the Montpelier City Council, the Central Vermont Regional Transportation Agency Committee and the Project Study Committee and was approved by the VTrans Project Development Team as the preferred alternative. The proposed roundabout included 2 approaches for Route 2, 1 for Route 302, 1 for Walker Motors and 1 for the Grossman parcel.

The intersection would be initially constructed as a single-lane roundabout designed to accommodate the largest permitted truck. The roundabout would also be designed such that it could be expanded to a 2-lane roundabout in the future if necessary with minimal changes. This alternative was chosen because it has the potential to meet all the goals of the study conducted. More specifically the scoping study indicates that:
  • The occurrence of injury and fatality accidents at a roundabout is lower than at a signalized or stop sign or controlled intersection
  • Both the Walker Motors and Grossman parcel approaches would be safer than their existing access points
  • Due to the geometry of the approaches, there would be room for Irving Oil to install an exclusive left-turn land on US Route 302 if needed for any proposed development on their site
  • Shorter queues are anticipated on US Route 2 with the roundabout alternatives, which creates less potential for driveway obstruction
  • There would be room across the Winooski River bridge for a sidewalk to connect the Winooski East Path with the with the roundabout alternative
  • There would be room for a sidewalk and bike lanes from Pioneer Street to the intersection (3 lanes become 2 on US Route 2 leaving room for the sidewalk and bike lanes)
  • A roundabout would provide a traffic calming effect and would serve as a gateway to slow traffic entering Montpelier
Project Cost
The total design / construction cost estimate for this project is $1,025,000 (including $825,000 for the roundabout and $200,000 for the US Route 2 approach work from Pioneer Street to US Route 302). Please note that these are 2005 estimates.