×

I-93 Expansion Ideas: Rethinking exits 14 and 15


Monday, May 29, 2017


A satellite view of the current configuration

Today marks the final installment of our three-day look at ideas for improving and expanding I-93 through Concord and Bow.

Four major interchanges will be the focus of public informational meetings on Wednesday and Thursday. 

The information sessions are set for Wednesday at Bow Memorial School and Thursday at Rundlett Middle School in Concord. Each meeting will begin with an open house from 4 to 6 p.m. with various concepts (generally three options per interchange) on display. A formal presentation will follow at 7 p.m., with opportunities for the public to ask questions.

On Sunday, we detailed the options for the I-93 and I-89 interchange and on Monday we focused on Exit 12. Today, we examine exits 14 and 15 in downtown Concord.

The major issue with exits 14 and 15 is that they’re positioned much too close together, forcing drivers to use the same stretches of pavement to weave on and off the highway.   

Changes and expansion to three lanes in each direction is complicated by the proximity of the Merrimack River to the east, and to the west by the Pan Am Railways rail line and many buildings, including the Unitil electricity substation, the Ralph Pill Marketplace and Burlington Coat Factory.

The work for exits 14 and 15 is part of a broader vision for I-93. The interstate was expanded to six lanes south of Concord many decades ago. This work contemplates widening I-93 to six lanes through the city.

The entire project is likely to cost in the range of $200 million. A total of $61.4 million is included in the state’s 10-year highway plan through 2028, about $46.5 million of which is for actual construction starting in 2024.

Under the state’s 10-year highway plan, construction wouldn’t begin until 2024 at the earliest, preceded by years of engineering and obtaining rights of way


CONCEPT D2: 

This mimics the configuration of the current interchanges, adding a lane on the interstate in each direction. The big change is that it removes the on-ramp to northbound I-93 from Loudon Road  (Route 9) at Exit 14. 

PRO: This is the cheapest and easiest of the options. The elimination of the ramp from Loudon Road to northbound I-93 allows the expanded interstate to be shifted slightly east, minimizing impact of an expanded highway in the “pinch point” where the highway is squeezed between the river on one side and the railroad and buildings on the other. The Stickney Avenue connection to Loudon Road would remain, and there would be no impact to the buildings. 

CON: Losing the ramp from Loudon Road to northbound I-93 will push some traffic onto Fort Eddy Road, as drivers make their way to Exit 15. The traffic weave on the cloverleaf of Exit 15 would remain.


CONCEPT F:

This creates separate roads, known as collector-distributor roads, on each side of the highway between exits 14 and 15. Basically, it turns the stretch of interstate between the exits into four separate, parallel roads – two lanes going through and two lanes getting off, in each direction. Exit 14 is proposed as what is called a single-point urban interchange, the same configuration that exists at Exit 13.

PRO: The connector roads would eliminate traffic getting onto and off the interstate between the exits, weaving back and forth over the same stretch of highway. Exit 15 would turn into a “clover stack,” a variant of the cloverleaf pattern that eliminates weaves between ramps. It would keep an on-ramp from Loudon Road (Route 9) to I-93 northbound.

CONS: This would expand the footprint of the freeway slightly to the west, colliding with the “pinch point.” This would eliminate access to Stickney Avenue from Loudon Road, require the Unitil substation to move, eliminate Stickney Avenue access to the Ralph Pill Marketplace, impact the Burlington Coat Factory building and shift the railroad corridor. 


CONCEPT O3:

This is the most complicated of the three options. It also creates separate roads to end weaves between and on the two exits, and it reworks Exit 14 extensively.

PRO: It would lower I-93 by about 20 feet at Exit 14, so that Loudon Road would pass over the interstate, rather than under it, as happens currently. This change, long discussed, would open up the area visually and allow the railroad to be shifted closer to the interstate, so that land along Stickney Avenue would no longer be bisected by the rail corridor, opening it up to development and access from Storrs St. 

CONS: Coming south on I-93 from Canterbury, the off-ramp for Loudon Road (Route 9) is pushed north of Exit 15. Confusingly, when going south you have to leave the highway earlier to get to Exit 14 than to get to Exit 15, even though you drive past Exit 15 first. 

Very expensive and probably would take the longest to complete. Loudon Road would have to be closed to traffic for months while I-93 was lowered, although traffic could continue going through on the interstate itself.

It would eliminate access to the Ralph Pill Building from Loudon Road, although connection is possible from Storrs Street. It eliminates the northbound ramp onto I-93 from Loudon Road at Exit 14.