Cemetery Brook Drain Tunnel Project Photos
Welcome to the photos page of the CBDT project website! Provided below are current photos showing the status of each of the major project locations, including the TBM Launch Zone and each of the Drop Shafts. Located at the bottom of this webpage is "Beyond the Site" with status photos or images associated with design, planning, major project milestones and various construction aspects of the tunnel project.
Project Site Status Photos
Site 1 - Launch Zone (Queen City Ave. Bridge)
Placement of the the Tunnel Boring Machine (TBM) a.k.a. "Granite Janet" into the launch zone site. The TBM comes in several different pieces that will be connected within the launch site before it begins drilling. This portion of the TBM is refered to as the front shield and houses the cutterhead controls for the machine.
Site 2 - Drop Shaft (DS) - 1 (Queen City Ave.)
Drilling of holes to complete controlled blasting within Drop Shaft 1. Once the holes are drilled to a 5 foot depth, material is placed to "blast" or break up the rock. Once a controlled blast is complete, excavation of rock and soil is completed, followed by installation of steel bracing as Drop Shaft 1 gets deeper. Steel braces and rock supports help hold the soil and rock in place to maintain a safe working space within the support of excavation (SOE) walls.
Site 3 - Drop Shaft (DS) - 2 (Union Street)
Placement of concrete on the bottom floor of the "adit" at DS-2. An adit is a short tunnel constructed horizontally through the rock, which will connect the completed Drop Shaft to the completed Tunnel. This adit is constructed by blasting and removing rock at the bottom of the drop shaft, roughly 70 feet below ground level. Concrete is added at the bottom to level the floor.
Site 4 - Drop Shaft (DS) - 3 (Beech Street)
Removal of blasted rock once the rock is broken up by controlled blasting (often called "mucking"). After completion of the controlled rock blasting in Drop Shaft 3, rock is removed and anchors are installed to support steel sheets within the support of excavation (SOE) or to stabilize any loose rock on the face of the excavation.
Site 5 - Drop Shaft (DS) - 4 (Wilson Street)
Pre-drilling operation to provide clearance for the installation of steel sheet piles. These piles are needed for support of excavation (SOE) installation to hold the soil back within Drop Shaft 4 excavation.
Site 6 - Drop Shaft (DS) - 5 (Taylor Street)
Site access road to future location of Drop Shaft 5.
Site 7 - Drop Shaft (DS) - 6 (Massabesic Street)
Installation of groundwater observation well to prepare for construction of future Drop Shaft 6.
Site 8 - Drop Shaft (DS) - 7 (Mammoth Road)
Installation of a water tap located in Mammoth Road for water supply at future location of Drop Shaft 7.
Site 9 - Consolidation Drainage Piping (Union, S. Willow, Cilley)
Excavation of soil and placement of the trench boxes or soil support systems (SOEs) for the installation of the new 60-inch drainage pipe near Union and Shasta Streets. Utilities such as gas, drinking water and sewer pipe have to be relocated and adjusted to fit the new drainage pipe in the ground.
Site 10 - Supplemental Vent Shaft (SV) - 2 (Maple & Silver)
Preparation and delivery of equipment to the most newest active work location on the project. A vent shaft for the tunnel will be drilled near Maple and Silver Street, which will allow air to escape from the tunnel when it fills with stormwater during rain events.
Previous Site Photo Links
Select the links below to view and download past project photos
September 2025
October 2025
November 2025
December 2025
January 2026
February 2026
March 2026
April 2026
May 2026
June 2026
CBDT Beyond the Site
This section includes major project milestones, TBM details, and miscellaneous photos of important project components that support the mining operation or major construction.
Project Milestone Photos
June 2026 - Delivery of two sections (sheilds) of the Tunnel Boring Machine arrive in Manchester from Germany (via Portsmouth, NH)
June 2026 - The Tunnel Boring Machine Arrives at the Launch Zone
June 2026 - The Tunnel Boring Machine Cutterhead Arrives at the Launch Zone
June 2026 - Placement of the Tunnel Boring Machine Front Shield into the launch zone excavation with members of the project team watching.
June 2026 - Drop Shaft 2 Rock Excavation is completed
June 2026 - The end of Drop Shaft 2 adit is completed. This rock face is the location that the DS-2 adit will connect to the tunnel, once the TBM mines past this location.
Tunnel Boring Machine (TBM) Photos
Tunnel Boring Machine cutterhead under fabrication in Germany
Tunnel Boring Machine interior with segment mold on conveyor, under fabrication in Germany
Tunnel Boring Machine interior behind the cutterhead, 16 cylinders that help push and drive, under fabrication in Germany
Tunnel Boring Machine interior precast concrete segment conveyor
Project Support Photos
Tunnel Segment Forms - Used to pour precast concrete tunnel liner segments at the remote production plant in Connecticut
Completed precast concrete tunnel segments - These pieces will be delivered from Connecticut to the launch zone site and stored until they are ready to be placed in the tunnel. These segments will be part of the finished tunnel walls.
Tunnel Boring Machine push frame design - Used at the start of the tunnel to push the tunneling machine into the ground
Tunnel Boring Machine push frame - The vertical section of the push frame assembly
Slurry plant installation at the Launch Zone. This plant is used to produce a thick liquid that will be pumped to the front of the Tunnel Boring Machine cutterhead. This slurry will support the excavated face of the tunnel and will also be used to carry the mined material from the tunnel back to the production plant.