Toledo Waterway Initiative

TWI Phase II Downtown Storage Basin

The Toledo Waterways Initiative (TWI) Program encompasses more than 45 separate projects over the course of 18 years, at a projected cost of $527 million

As part of Phase II, Turn-Key Tunneling constructed a 725-ft rib and board tunnel utilizing a hydraulically driven tunnel shield. The 12-ft diameter tunnel served as the initial pass for the two-pass tunnel system and acts as the final host for the 110-in sanitary sewer.

Turn-Key Tunneling constructed a 32-ft diameter vertical shaft for a junction chamber which served as the reception shaft for the shield removal. The tunnel was installed in lean clay with several large boulders located throughout the heading.


November, 2019


Kokosing Industrial, Inc.
6235 Westerville Road, Suite 200
Westerville, OH 43081
Kris Trouteaud

Project Manager:

Brian Froehlich, PE President


City of Toledo
One Government Center
640 Jackson Street
Toledo, OH 43604