Mysterious structure in Lake Ontario part of new Ashbridge’s Bay treatment plant project

A large rig in Lake Ontario near Ashbridge’s Bay is part of a project to create a new 3.5 kilometre outfall tunnel from the wastewater treatment plant.

The platform and barge floating next to it have provided plenty of fodder for those frequenting Toronto’s beaches and Tommy Thompson Park for a couple of months now.

“It’s been a very big curiousity even to the members at Ashbridge’s Bay,” yacht club Kathleen Walker said. “The club put out a notice saying they’re drilling and to keep 300 metres away.”

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Those involved in a variety of discussions online have speculated it could be anything from a deep water cooling project to an alien invansion.

“We had so many different stories going on,” Tim West, a yacht club employee said. “We thought it was an oil rig, then all of a sudden it became for boats to move through a canal.”

The structure has actually been put in place to do some testing before design and construction of the new tunnel to move treated water deeper into Lake Ontario.

“We’re doing some geotechnical work on the lake bed,” the director of wastewater treatment for the city, Frank Quarisa, said.

“There’s a series of bore holes that are being drilled through the lake bed to find and locate exactly where the bedrock is.”

The current 70-year old pipe is just one kilometre long, is at capacity and is reaching the end of its service life.

During heavy rainfall, the city’s current sewage system often overflows and creates problems along the Lake Ontario shoreline and beaches by bypassing the Ashbridge’s Bay Treatment Plant.

Design for the new seven-metre diameter outfall tunnel should be completed next year before construction begins in 2018.