Worked started on Monday doing test bore holes for the new Downtown Ottawa Transit Tunnel (DOTT). Hopefully, the cost won’t be wasted if the anti-tunnel Watson gets elected mayor.
The first bore hole is on the park just below the Juliana Apt building near the corner of Queen/Bronson/Hill Street. Each hole boring takes one to two days. While drilling, the crew takes rock samples to ensure what is deep under the downtown is what geologists currently expect to be there. The drilled hole will be capped off with a removable lid, but the hole underneath remains, and will have monitoring equipment in it to measure water flows (the DOTT is for dry people, not storm water). The entrance to the tunnel will be a few hundred meters west of this first hole, roughly where Brickhill Street runs between the two city parking lots on the north side of Albert.
Some of the later holes along Albert Street will be 160′ deep, deeper than previous bore holes in the downtown core. Finding the deep water tables and the direction of the water flow (the “thalweg”) will be new information that will also benefit future municipal and private sector construction projects.
The primary purpose of the Geotechnical and Hydrogeological Investigation will be to further advance our knowledge of the existing geology and groundwater conditions along the tunnel alignment. This information will inform the preliminary engineering and design of the LRT project.
A total of 23 geotechnical boreholes and 15 environmental boreholes will be drilled along the tunnel alignment. Work on each drill site will run from two to five days and on some locations minor traffic re-routing will be required.
Work begins on the western segment and will move East along the tunnel alignment.
Councillors of affected wards have been contacted and residents and businesses in proximity to the boring will be advised prior to commencement.