Documents Reveal The Boring Company Studied a Music City Loop Tunnel Beneath the Cumberland to Nissan Stadium

For months, a Music City Loop connection beneath the Cumberland River has been publicly discussed as a possible future expansion.

But documents reviewed by LOOP Nashville show The Boring Company had already taken the idea considerably further.

A December 2025 Environmental Impact Assessment prepared for the project describes a proposed Broadway Alignment extending approximately 2.5 miles from Nissan Stadium to Centennial Park, generally following Broadway and West End Avenue and passing under the Cumberland River. The assessment identifies the proposed Loop tunnels as two parallel bores approximately 13.12 feet in diameter.

More significantly, the assessment maps the river crossing.

One project figure is explicitly labeled “Broadway Alignment: Centennial Park to Titans Stadium.” It traces the proposed tunnel across downtown Nashville and beneath the Cumberland to the East Bank. At the river, the map identifies a crossing point labeled “Cumberland River BNA-002-Broadway Sta: 176+50.”

The figure’s source line is equally notable. It identifies “The Boring Company Alignment 10/20/2025” among the sources used to prepare the map.

That does not mean the Cumberland crossing was approved for construction or that The Boring Company committed to building it. But it establishes something that has been largely missing from the public conversation: by October 2025, a Music City Loop tunnel beneath the Cumberland had progressed far enough to appear on a TBC project alignment and undergo environmental and geological analysis.

More than a conceptual idea

The distinction matters because the East Bank connection was being discussed publicly in much more tentative terms at roughly the same time.

During a November 2025 virtual town hall, The Boring Company President Steve Davis described a West End line that could run from Interstate 440 past Centennial Park and Vanderbilt, merge into Broadway and continue to Riverfront Park. He then said that, “if the stars align,” the route could continue beneath the river to Nissan Stadium.

That made the East Bank segment sound conceptual. The environmental documents tell a more developed story.

Before that town hall took place, consultants were already evaluating an October 20, 2025 TBC alignment that extended from Centennial Park to the stadium area and included a defined Cumberland River crossing.

A detailed land-use figure in the assessment shows the proposed route approaching Riverfront Park, crossing beneath the Cumberland and continuing onto the East Bank near Nissan Stadium. Once again, the crossing is labeled BNA-002-Broadway Sta: 176+50.

This was not a final construction drawing. But it was also more than an aspirational line pointing east. It was a route being studied.

The study also examined the geology beneath the river

The assessment did more than identify where a tunnel could cross the Cumberland. It examined the geology beneath it.

That matters because tunneling under a major river in Nashville is not just a routing question. It is a geology and groundwater question.

According to the EIA, the portion of the proposed tunnel beneath the Cumberland would pass through Carters Limestone below the assumed riverbed. The report notes that Carters Limestone can be susceptible to karst development and groundwater intrusion.

The aquatic-resources analysis says current tunnel-boring plans placed the proposed tunnel crown approximately 25 feet below the depth of the Cumberland River bed. The geology section describes the crossing as maintaining more than 25 feet of overburden beneath the riverbed.

That is one of the most important engineering details in the document.

The consultants concluded that with the tunnel positioned in competent rock and well below the riverbed, the potential for groundwater-related impacts would be low. The report also makes clear that the final depth was not fixed: TBC would continue subsurface investigation as design progressed and could adjust the tunnel depth to avoid unfavorable geological conditions.

In other words, the environmental review did not simply assume a Cumberland crossing would be possible. It considered the geological conditions beneath the river and concluded that the crossing could be managed using standard geotechnical and tunneling practices.

Then the Cumberland crossing disappeared from the public route

That makes The Boring Company’s current public description of the Music City Loop especially notable.

As of its August 14, 2026 update, TBC describes the Broadway Alignment as extending southwest from Lower Broadway, continuing along West End Avenue past Centennial Park and Vanderbilt, and terminating near Interstate 440.

That public description does not extend east from Lower Broadway beneath the Cumberland and does not include Nissan Stadium.

That is a meaningful change from the alignment used in the 2025 environmental assessment.

The EIA studied a line running from Centennial Park through West End and Broadway, beneath the Cumberland River and onto the East Bank at the stadium area. The currently announced Broadway Alignment stops on the downtown side of that route.

The publicly available materials reviewed by LOOP Nashville do not explain why the Cumberland portion disappeared. It could have been deferred to a later phase. The alignment could have changed as engineering progressed. Or the East Bank segment could simply fall outside the portion TBC currently intends to build first.

The documents do not answer that question. What they do show is that the East Bank connection progressed substantially beyond the level of public speculation.

Why the crossing would matter

A tunnel beneath the Cumberland would fundamentally change the role of the Broadway line.

Without it, Lower Broadway functions as the eastern end of the West End corridor. With it, the same corridor could directly connect the East Bank and stadium area with Lower Broadway, Midtown, Vanderbilt, Centennial Park and potentially the broader Music City Loop network.

The river is one of Nashville’s most significant transportation barriers. Surface traffic must funnel onto a limited number of bridges to move between downtown and the East Bank. An underground crossing would create another path across that barrier without adding another bridge or routing more vehicles onto downtown surface streets.

That possibility has become more significant as the Loop itself has grown. The Boring Company now describes the Nashville project as an almost 25-mile network, and its October update says more than 40 stations are in various stages of planning and design.

In that context, a Cumberland crossing would not simply be a stadium spur. It could provide a foundation for future underground expansion east of the river.

None of that has been announced. But the environmental record shows the first step across the river was already studied.

What the documents do not prove

There are important limits to the finding.

The EIA is not a construction permit. It does not prove that TBC has decided to build the river crossing. It does not identify a construction timeline or a publicly committed East Bank station. And an environmental-study alignment should not be treated as a final engineering drawing.

The assessment itself says geotechnical analysis, utility coordination and engagement with public agencies could result in changes to the project design, and that tunnel depth would continue to be refined as additional subsurface information became available.

Nor was the general possibility of a Cumberland crossing entirely unknown. Local news outlets previously reported TBC officials discussing the idea in broad terms.

What appears to have received little attention is how far the concept had already progressed inside the environmental documents: a defined alignment, a specific crossing location and a geological analysis of tunneling beneath the river.

An old alignment raises a new question

The Music City Loop has evolved quickly since it was first announced. The network has grown, more stations have entered design, and new construction sites and property acquisitions have emerged as TBC has begun tunneling beneath Nashville.

The Cumberland crossing appears to have moved in the opposite direction.

It was included in the October 2025 alignment used for the project’s environmental assessment, but it is absent from the Broadway route TBC publicly describes today.

Whether that means the East Bank connection was abandoned, redesigned or simply pushed into a future phase remains unknown.

But the environmental record makes one point clear: The Boring Company did not merely talk about someday taking the Music City Loop beneath the Cumberland River. Its consultants studied an actual TBC alignment that did exactly that, and the route led directly to the stadium area.