Work begins on $232M tunnel project to combat Ottawa's sewage overflow

Major Ottawa-area politicians from all levels of government gathered at the banks of the Ottawa River Tuesday for an announcement confirming that funding is lined up for a massive four-year construction project that will reduce the amount of raw sewage flowing into the river.

Construction is set to begin on an underground combined sewage storage tunnel (CSST), a major part of the Ottawa River Action Plan and a project with a $232.3-million price tag.

The federal government and the provincial government have agreed to each contribute $62.09 million to the project. The remainder, an estimated $108-million, will come from the City of Ottawa.

“We appreciate the previous government for starting the process and the current government for finishing it,” said Mayor Jim Watson, who made the announcement with provincial Infrastructure Minister Bob Chiarelli and Environment Minister Catherine McKenna.

So far this year, over half a million cubic metres of rainwater mixed with raw sewage has flowed into the Ottawa River, contributing to beach closures and E. Coli levels.

The overflow problems come from the way sewers were designed between the 1880s and the 1960s. Heavy downpours can overwhelm the city’s system of drainage and sewers. Instead of backing up sewage into basements, the excess water – including raw sewage – is dumped into the Ottawa River.

While most of the beach-closing, post-rainfall E. coli comes from storm outlets and goose excrement, sewage overflow travelling downriver has increased contamination in many river sites east of downtown.

The solution the city has chosen is a combined sewage storage tunnel. Instead of letting the overwhelmed system dump sewage into the river, two massive underground storage tunnels will hold the water until it can be treated.

“This has been my number one priority for a number of years. Too many days the beaches are closed, and for many families that’s their only recreational opportunity in the summer,” said Watson.

While clean beaches and less closures were touted by a number of politicians attending, the new measures won’t necessarily have a big effect on western beaches like Westboro and Brittania. Instead the biggest difference will be downriver at sites like Petrie Island.

The City of Gatineau has only just begun tracking the amount of overflow from their side of the river. Watson said while that pollution in a concern, the river is wide enough that it doesn’t have a major impact on Ottawa sites.

“Obviously the river doesn’t respect boundaries,” he said. “We’ll be able to capture 95 per cent of the pollutants. Our folks tell me that because of the width of the river it will meet our standards of ensuring that we have the cleanest water possible.”

Watson said preliminary work has already begun. Construction will begin this year, with the project aiming to be completed in 2020.