OTTAWA — The City of Ottawa has announced a major milestone in its Combined Sewage Storage Tunnel (CSST) project: the completion of the north-south leg of the tunnel.
The milestone was reached recently when a tunnel-boring machine emerged through a cliff behind the Supreme Court of Canada on Wellington Street, noted a mid-August media statement.
Tunnelling began on Chamberlain Avenue in December 2017, continuing for over two kilometres and up to eight storeys below Kent Street, before arriving at the Ottawa River behind the Supreme Court of Canada. The 250-metre-long tunnel-boring machine will now be dismantled, moved and re-assembled to begin tunnelling the east-west tunnel from New Edinburgh to LeBreton Flats later this year, the statement explained.
The additional capacity of the CSST will reduce the frequency of combined sewage overflows during storms entering the Ottawa River, and in addition, the CSST will also cut down on the risk of basement flooding in low-lying areas in the city’s core.
The CSST is a $232.3-million project, with the Government of Canada and the Province of Ontario each providing $62.09 million. The City of Ottawa has committed $108 million towards the project, which is a component of the Ottawa River Action Plan.
“The Ottawa River is a critical water source in the nation’s capital region and has provided many generations of people — from the Algonquin People to the residents of Ottawa today — with a source of drinking water as well as a place for recreation and leisure. The CSST is a major investment to protect the health of this precious water resource,” commented Ottawa Mayor Jim Watson in the statement.