How light rail on Nashville corridors could work — and where the challenges are

As Mayor Megan Barry's administration pursues the first spoke of a light rail system in Nashville, a new report shows how the entire five-corridor network could work, what it might look like, and where Metro faces construction and right-of-way challenges.

These details are laid out in the new "high-capacity transit briefing book" released by the Metro Transit Authority on Friday that found "no fatal flaws" in developing high-capacity along the five corridors.

The report's release completes the final phase of the region's nMotion transit plan, which outlines a proposed $6 billion transit system for Middle Tennessee over the next 25 years.

Barry has already proposed moving ahead with new light rail service on Gallatin Pike and Main Street in East Nashville. She wants to hold a public referendum in May that would let voters decide whether to dedicate new tax revenue to pay for transit projects.

► More:Mayor Barry commits to light rail on Gallatin Pike, kicks off public vote for funding transit

Nolensville Pike, Murfreesboro Pike and Charlotte Avenue are also identified for light rail in the nMotion plan while Dickerson Pike is targeted for bus rapid transit.

"This report clearly shows that Nashville can build an effective transit system along our pikes and corridors," Barry said in a statement. "We will use this data and research to further develop a comprehensive transit plan that is equitable, sustainable, and reduces congestion by giving more transportation options to Nashville area residents."

Though the report — led by the transportation planning firm Nelson\Nygaard Consulting Associates and HDR, Inc. — found no major issues that would prevent the construction of high-capacity transit on any of the corridors, it did identify what it calls "pinch points."

► More:What could light rail on Nashville's Gallatin Pike look like?

► More:Mayor Barry looks to May election for 2018 transit funding referendum

These are challenges where transit design would require "intense collaboration" among project designers, neighborhoods, adjacent property-owners, the Tennessee Department of Transportation and other stakeholders such as the railroad CSX. 

"What it's intended to do is give people a broad view to say, in these corridors, here's conceptually some of the issues," MTA CEO Steve Bland said, referring to the study. "The general takeaway is there's no fatal flaw.

"They're not unusual challenges," he said of construction issues highlighted in the report. "They're challenges faced by a whole bunch of other cities."

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The study says that Murfreesboro Pike is currently the most equipped to handle new transit construction followed by Gallatin Pike and Charlotte Avenue.

Murfreesboro Pike also has by far the fewest right-of-way issues that could pose challenges for light rail, the report says. Gallatin Pike, where Barry wants to build first, also faces limited right-of-way challenges, the report argues. 

The study does not discuss how the high-capacity transit system would function downtown — a key consideration to making any transit system work.

There are also no cost estimates attached to any of the five corridor projects.

Barry has not announced a timetable on moving forward with light rail on Gallatin Pike, instead pointing to approval of the transit funding referendum as a first step. The mayor has not identified the revenue streams she hopes to target for transit.

Here's what the report has to say about each corridor:

Gallatin Pike

The report says the initial segment of light rail on Gallatin Pike would extend 5.1 miles along Main Street, Gallatin Avenue, and Gallatin Pike, and go from downtown Nashville to Briley Parkway, stopping short of entering Madison.

To make light rail work on Gallatin Pike, sidewalks in some areas would have to be narrowed, according to the study.

On the stretch of Gallatin Pike that is south of Eastland Avenue, the report cites the limited space between the roadway and existing structures as a challenge for construction. Metro owns property near East Nashville High School, which could help with construction flexibility near that stretch.

On the north end of Gallatin Pike, the report cites the rail bridge that crosses Gallatin Pike at Kirkland Avenue as the greatest challenge. Consultants say that while it would be possible to construct light rail within the footprint of the existing structure, doing so would require a dramatically reduced cross-section, likely a single-track light rail line, which would "compromise the performance of the entire corridor."

The Main Street portion of the corridor has the least amount of available right-of-way, particularly for stations. Conversely, it says that generous setbacks between buildings and the road between Kirkland Avenue and Eastland Avenue would mean little additional right-of-way would be needed.

"Gallatin Pike is densely developed between downtown and Eastland Avenue. Consequently, to minimize impacts on existing properties, sidewalks would need to be narrower than in other areas," the report states. "Beyond Eastland Avenue, where development is less dense and setbacks are wider, it would be possible to incorporate features such as wider sidewalks and landscaping."

Charlotte Avenue

Light rail on Charlotte Avenue would initially run 3.7 miles between downtown Nashville and White Bridge Road with approximately eight stations. It says neighborhood access points would be key, and that access points to hospitals on Charlotte Pike would require special turning locations and signal designs.

Transmission poles between 40th and 33rd avenues would present several construction challenges, the report says. Highway underpasses at Interstate 40 and 440 could likely
accommodate light rail, but dense business districts between 25th Avenue and I-40 would pose challenges.

The report says that some additional right-of-way would be necessary in all station areas on Charlotte Pike as well as most left-turn locations. It says additional roadway would be advantageous in the area close to Richland Creek, in particular, to avoid a single-track light rail configuration.

"Although Charlotte Avenue is the most densely developed corridor under consideration, light rail could be implemented without major challenges or
right-of-way constraints," the report states. "In all station areas along Charlotte Avenue, some additional roadway expansion would be required to accommodate platforms and turning lanes."

Dickerson Pike

Bus rapid transit is a type of transit that operates on dedicated lanes but utilizes buses instead of rail. The plans calls for BRT to run 4.4 miles down Dickerson Pike between Briley Parkway and Interstate 24 downtown.

The report says that Dickerson Pike was identified for BRT instead of light rail because of its lower residential and commercial uses and because of constrained right-of-way that present unique challenges. It says there are overall few challenges to constructing BRT on Dickerson Pike and that both center and side-running BRT will be explored.

"There is sufficient right-of-way along the majority of Dickerson
Pike for implementing the minimum width side-running BRT design," the report states. "Between stations, very limited additional right-of-way would be needed and there are very few structural conflicts."

Murfreesboro Pike

Consultants have proposed the first phase of light rail on Murfreesboro Pike spanning 8.2 miles and connecting to airport terminals along an exclusive right-of-way parallel to Donelson Pike.

The plan calls for eight to 10 stations and an eventual connection to freeway BRT on Interstate 24. 

Murfreesboro Pike presents relatively few construction challenges, the study says, but it cites the bridge over Browns Creek and the rail overpass at Menzler Road as "potential pinch points."

Right-of-way needs would be minimal along Murfreesboro Pike. 

"Murfreesboro Pike is less developed than other potential light rail
corridors featuring large setbacks from the roadway and ample surface parking," the report states. "This low-density development could facilitate corridor construction and create opportunities for transit-supportive development in the future. The airport would be an important asset for the corridor attracting riders and anchoring light rail service."

Nolensville Pike 

Light rail on Nolensville Pike would extend 5.5 miles from downtown Nashville to Harding Place and include approximately eight stations. 

In terms of construction, the study says light rail would operate in a couplet close to downtown when the corridor is 4th Avenue South, heading away from downtown, and 2nd Avenue South, heading into downtown.

Right-of-way needs would vary significantly, the report says. There would be no additional rights-of-way needed north of Walsh Road except near station areas. It says there's enough right-of-way near the Fairgrounds Nashville to create a wider corridor cross-section with landscaping.

"Light rail would pass through neighborhoods with a mix of development types requiring a variety of trade-offs," the report states. "Challenges include difficult rail crossings, dense business districts with limited right-of-way, and restrictive adjacent land uses (such as the Nashville Cemetery)."

Reach Joey Garrison at 615-259-8236, jgarrison@tennessean.com and on Twitter @joeygarrison.