4/1/26 MUSIC CITY LOOP BLOG POST 

Welcome to the first official Music City Loop blog post where we are tunneling! 

This is an incredible accomplishment that is a product of the support by Nashville and Tennessee, thorough regulatory review and process, strong local vendors, and hard work from the team. Most importantly, it is only the beginning and there is a lot more work to be done.

What Has Happened Since the February 1 Blog Post? 

Construction: Since the February 1 update, as mentioned, our team has officially begun tunneling! In late February TBC and TDOT fully executed the TDOT tunnel permit and lease agreement after roughly a 7-month technical review process. 

Tunneling process:

The first four weeks of tunneling are considered the launch phase, during which Prufrock-MB1 is tested, calibrated, and advanced far enough underground to connect the trailing support gantries, resulting in slower initial tunneling due to system setup, rock removal logistics, and machine calibration before ramping up to full production. Gantry support platforms carry water, hydraulics, ventilation, conveyor belt, power, and navigation systems. There are five gantries in total, each serving a specific function. With all gantries connected, the TBM is approximately 150 feet long, which is actually rather short for a TBM.

Excavation begins with the rotating cutterhead at the front of the machine, where disc cutters fracture and grind the rock while water is applied to reduce heat, control dust, and increase penetration rate. Hydraulic grippers brace against the tunnel walls to stabilize the machine as thrust cylinders push the cutterhead forward into the rock face. The broken rock then falls onto a conveyor system that carries the material out of the tunnel into a muck pit. 

The team is likely tunneling as you read this! The team is scaling to high production, ensuring all machine subsystems and processes are optimized so the tunneling process can be established for mass production. 

A major part of high production is the Vertical Cassette and belt system, which enables continuous tunneling. The excavated rock travels the length of the tunnel to a controlled area on site, where it is then picked up with an excavator and loaded onto dump trucks.

The initial lessons learned from launching MB1 have been communicated to the Engineering team, who have incorporated them into MB2, currently under production in Bastrop, Texas.  Prufrock-MB2 will ship to Nashville in early April, and will launch from Lot 16, excavating a parallel alignment to MB1.

Permitting/Approvals: As noted in previous blog posts, Music City Loop requires 45 separate permits and approvals, with 37 needed in order to begin tunneling. All 37 permits and approvals required ahead of tunneling have been obtained. The remaining 8 permits relate to additional launch sites required to complete the Broadway and Airport alignments. Key approvals include:

  • The fully executed TDOT Tunnel Permit and Lease Agreement, following over 7 months of technical review. This approval (received on February 25) authorized 25 miles of tunnel within the TDOT right-of-way and allowed TBC to begin tunneling operations within the permitted corridor. This is a significant accomplishment, and we are grateful to work alongside TDOT and FHWA throughout this process.

  • The Metropolitan Nashville Airport Authority, which unanimously approved (8–0) a Music City Loop connection and station at Nashville International Airport and 

  • The Music City Convention Center Authority in downtown Nashville also unanimously (8-0) approved the Music City Loop tunnel easement, and the teams are now working together to finalize the station design. 

Community Engagement: Music City Loop is grateful for the continued hospitality of the Nashville community. Through ongoing conversations with residents and community leaders, the team has been able to share how the system will operate while gaining valuable insight into the city’s priorities. These discussions help ensure the project aligns with the broader needs of the community.

  • Meeting with Community Leaders: Collaboration with government partners, local organizations, and business leaders remains a priority. We continue to host regular tours at our Nashville launch site. To date, we have hosted over 100 people to tour the site since we have started tunneling! If you are interested in touring the launch site, please reach out to nashville@boringcompany.com, and we will do our best to accommodate. 

  • Hiring and Workforce Development: TBC continues to recruit local talent and partner with Nashville-area universities to connect with students and recent graduates. We recently hosted a recruiting event at our launch site and plan to attend several career fairs in the coming months. As the project expands, additional roles are being added to support the development of a strong local workforce. For open positions, please visit here.

  • Community Organizations and Volunteering: To date, TBC has engaged with more than 200 community, educational, nonprofit, and professional organizations and participated in over 100 in-person volunteer events. Community engagement efforts continue to expand across Nashville.

  • Public Inquiries: We have responded to over 150 inquiries submitted to nashville@boringcompany.com - keep the messages coming! Every message helps us better understand community priorities and build a system that reflects Nashville’s needs.

TBC X Account: Stay up to date on all things Music City Loop by following @boringcompany on X. Updates and live X Spaces will continue to be shared as the project progresses. 

While not directly related to Music City Loop, The Boring Company recently held a “Tunnel Vision Challenge,” a competition inviting the public to submit ideas for tunnel projects. Nearly 500 proposals were submitted, and while the Hendersonville Utility Tunnel was not selected as one of the three official winners, it was identified as a particularly compelling project. As a result, The Boring Company is continuing to work with Hendersonville and hopes to build it! More information can be found here.

The more we learn about Nashville, and the more time we spend with its state and local partners, the more exciting Music City Loop becomes. Your willingness to engage, ask questions, and help shape this project is invaluable. If there is anything we can improve or any information you’d like to see, please reach out anytime at nashville@boringcompany.com