Montreal sewage dump review by scientific panel urges caution

A panel of scientists asked to reviewMontreal's controversialplanto dump eight billion litres of raw sewage into the St. Lawrence River has concluded that the city should onlyproceed with the releaseonce steps are takento better understand and mitigate theenvironmental impacts.

The panel hasraised a number of questions about the plan, pointing outgaps ininformation aboutthe environmental effects and the need to address them in the public interest.

But the scientistssaid the city's plan is preferable to an accidental release of waste water caused by Montreal'sdecaying sewer system.

The release, should it proceed, would allow Montreal to work on a sewer interceptorthat has deteriorated.

The panel noted thatthe planned release would be carried out at a time of year when fish aren't spawning, thereby minimizing a key environmental concern.

It agreed thatthe fall is the best time for such a move.

The report recommended improvements to the city's plan, including better monitoring of the discharge plume beyond the Island of Montreal,the implementation of an emergency plan for cleaning affected areas, particularlynear the SorelIslands northeast of Montreal, and a mobile treatment unit for use at sites such as hospitals or industries wherepotentially toxic discharges could enterthe sewer system.

In a news release, the City of Montreal said it would study the panel's recommendations to determine which are priorities and which can be acted on at a later date.

The decision to approve or deny the plan now rests with federal Environment MinisterCatherine McKenna.

Montreal's plan has already beenapproved by Quebec's Environment Ministry, andthe city says there are no alternatives that would allow it to carry out the required maintenance.

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Conclusions questioned

Sarah Dorner, an associate professor in the department of civil, geological and mining engineering at cole Polytechnique, said she agrees with the report's assertion that a planned dump is the preferable option.

From a civil engineer's perspective, the solutions they're proposing just don't make technical sense. SarahDorner,colePolytechnique

She questioned, however, whether the panel had the right mix of experts to address certain critical questions.

"They didn't have any construction engineers, any civil engineers these were chemical engineers," she said. "We had chemical engineersasked to solve civil engineering problems.

"From a civil engineer's perspective, the solutions they're proposing just don't make technical sense. For a lot of these mitigation measures, you need people who know about pipes and pumps, because that's what this is really about."

Plan on hold until Nov. 9

Montreal announced its plan to dump the raw sewage in September, sayingit was necessary in order to divert effluent temporarily froma major sewer interceptor as part of the Bonaventure Expressway rebuilding project.

The plan called for the sewage to be dumped at the end of October to minimize possible effects onthe river's ecosystem.

The announcement sparked apublic outcry, prompting former Conservativeenvironment minister Leona Aglukkaqto intervene and haltthe plan while an independent scientific assessment of the sewage dump was conducted.

A ministerial order that Aglukkaqissuedforbids Montreal from proceeding with the sewage dump untilNov.9.