Canadian Consulting Engineer
Manitoba considers $600 million scheme to expand Winnipeg FloodwayEngineering
The Government of Manitoba is considering what to do about expanding flood protection in and around Winnipeg follow...
The Government of Manitoba is considering what to do about expanding flood protection in and around Winnipeg following the release of a report considering two main options.
KGS Group Engineering Consultants of Winnipeg, with Rick Carson, P.Eng. in charge, considered either expanding the existing Floodway around the city, or alternatively to build a set of dams, diversion channels and a major earth dam south of the town of St. Agathe.
Ste. Agathe was one of the main communities and farms to the south of the provincial capital that was inundated by spring overflow from the Red River during the great flood of 1997. The city of Winnipeg itself was largely saved, but it was touch and go.
Since then the government has been studying what to do to avoid a recurring disaster, and everyone agrees that something must be done quickly. Data shows that the existing Floodway has a 37% risk of being overwhelmed during the next 50 years.
According to the KGS Group report, the option to expand the Floodway has many advantages, though it is the more expensive scheme. The Floodway would be almost doubled in capacity, from 60,000 cfm to 140,000 cfm. According to the report it would perform better than the Ste. Agathe option if its capacity were exceeded. Also it would have more potential for recreational uses. The major advantage of the Floodway expansion, however, seems to be that it would not involve legal and land negotiations, whereas building the Ste. Agathe structures would require First Nation and International permits because it would result in land flooding to the south.
Another advantage to the Floodway expansion option is that flood protection would increase every year as it was being built. The Ste. Agathe structures would not provide any increased protection until the entire project had been fully constructed – which could take several years.
In terms of cost, however, the Ste. Agathe option is estimated to cost $543 million, compared to $660 million estimated to expand the Floodway.
Public reaction to the KGS report – which was released last November – has been mixed. Over 1,000 people attended public sessions held by the Manitoba Clean Environment Commission in January. According to the commission’s report, several participants felt that the consultants’ terms of reference were too narrow. They felt that the study focused on protecting the city of Winnipeg whereas it should have considered a much wider geographic area of the entire Red River Valley. Other participants argued for an even more foolproof barrier. They wanted to study options for a “super” floodway that would afford protection against a 1-in-1,000 year flood, instead of the 1-in-750-year flood protection considered in the study.
The public hearings also heard a lot of concerns about compensation. Many victims of the 1997 Flood still had not received compensation, and there were consistent request to settle these outstanding claims before proceeding with any new construction.
The premier of Manitoba, Gary Doer, has ordered an all-party committee to study the options. It met for the first time last month. All three levels of government will likely contribute to the construction project.
KGS Group of Winnipeg was the prime engineer responsible for the study: “Relative Benefits of Winnipeg Flood Protection Options.” They were assisted by InterGroup Consultants who studied the socio-economic impacts, and North South Consultants who contributed studies of the environmental, aquatic and biological issues.