This concept places a new road/connector to the west of the underpass. It involves a new intersection at both Mechanic and Mascoma Streets, a bridge with adequate horizontal and vertical clearance under the RR, and a sidewalk on one side. Two options were studied, one on each side of the Children’s Center building. Option 2 is shorter, but too steep. It also adversely impacts the Children’s Center access. The option has been pursued to include plan, profile, and sections. Further study may allow the 17% profile grade to be reduced, but was not done as part of this study.
Option 1 is the preferred alternative of these two. It achieves the desired grade separation with the RR. However, the northerly profile is steeper than the city’s desired maximum grade (12.8% v. 10%). Given the extremely short distance, this should not be a problem. The alignment connects with Peabody Street. This layout achieves a 90 degree intersection and is at the crest of Mascoma Street, providing the best sight distance in both directions. The alignment could be shifted to intersect with Bomhower street to the west. This would give additional length to reduce profile grade, but intersect with less than 90 degrees, and have a sight distance limitation to the east.
The project has the
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