A tunnel to replace Interstate 81's current elevated path through downtown Syracuse could take four possible routes through the city.
The New York Department of Transportation revealed tunnel options ahead of a meeting to explain all 16 possible variations of a new Interstate 81 in Syracuse.
Interstate 81 runs from the Canadian border in the north to the Pennsylvania border in the south. The 50-year-old highway carries thousands of cars each day through Syracuse.
But the 1.4 mile elevated stretch of the roadway through the city's heart is crumbling and needs to be replaced. Transportation planners are in the midst of a lengthy and hotly debated discussion about how to replace the road, known as a viaduct.
The state has set a 2017 deadline for that decision.
The future of the roadway boils down to four main options, each with its own variations: rebuild the viaduct to modern standards, replace the highway with a street-level boulevard and divert the highway around the city (likely I-481), build a depressed highway, or tunnel the highway under the city.
Ahead of a public presentation by DOT officials Thursday evening, the four variations on a tunnel were released:
- Tunnels 1 & 2, current alignment: Dig a "cut and cover" style tunnel along its current path parallel to Almond Street, with Almond Street rebuilt above it. The options vary in the length of the tunnel. In the first, the tunnel would run one mile and re-emerge at East Genesee Street. In the second, it would run two miles underground to Butternut Street. It would take five to six years to construct.
- Tunnel 3, western alignment: A tunnel could be built slightly west of the I-81's current path, under Townsend Street. While this would affect more homes and properties, DOT says it would not disrupt traffic flow. The ground under Townsend Street also offers better soil conditions to support a tunnel.
- Tunnel 4, eastern alignment: The fourth option provides for the longest - five miles - and deepest - 81 feet - tunnel. A tunnel would be built from the current I-81/I-481 split and travel east of the Syracuse University campus. It would resurface at the I-690 interchange before going back underground, turning sharply west, and reconnecting with I-81. It would require a "substantial" number of property seizures - about 100. It's also the most expensive option.
Cost estimates for the different tunnel options range from a low estimate on the Almond Street tunnel of $1.6 billion to the high of the eastern alignment, $3.9 billion.
The tunnel presentation was prepared by an 80 member working group. Concurrently, the DOT is preparing an environmental review of the different options.
DOT officials will explain the 16 options in public briefings Thursday evening at the Everson Museum, 401 Harrison St., in downtown Syracuse at 4 p.m., 6 p.m. and 7:30 p.m.
A second meeting to outline more details on the options will be scheduled for this summer, the DOT said.