Canadian Consulting Engineer

Whats New…

WATER...

December 1, 2005   Canadian Consulting Engineer

WATER

Beavers and operators blamed for Kashechewan

When E-coli contamination was found in the water supply of the Kashechewan First Nations reserve in late October, hundreds of residents of the remote reserve near James Bay were airlifted out. The Cree community’s water treatment plant was built 10 years ago at a cost of $3.6 million.

Initial media reports suggested that the E-coli problem was because the plant was not adequate for the 1,900 population and because an intake was located downstream from overflowing sewage lagoons. In fact, the intake is on a different stream system, but when beaver dams blocked the outlet from the sewage lagoons, sewage backed up and contaminated the water source.

Timmins-based engineering firm B.H. Martin Consultants (not the designers of the plant) examined Kashechewan’s water supply in 2002 and told the band how important it was to break up the beaver dams. It had not been done in recent years. Compounding the problems, the plant’s automation system had not worked so the operators tried to run the plant manually. They turned off the alarm system years ago, and did not fix a $30 chlorinator. After the crisis broke, Chris LeBlanc of Northern Waterworks, who was brought in by Health Canada, found the chlorinator had an airlock. The problem was fixed and a day later, he was drinking water from the plant tap.

EDUCATION

Manitoba engineering students have new home

Engineering faculty and students at the University of Manitoba moved into a new classroom building in September, sharing it with the department of computer science. The six-storey Engineering and Information Technology Complex was built to replace the former classroom building that was demolished. It contained the fondly remembered drafting studio known as “Room 229.”

The new building has a large atrium, design studios and the dean’s offices on its main floor, with lecture theatres and offices above.

Renovations to the engineering laboratory building next door are also under way. The design team for the new building and the laboratory building renovation is led by Stantec, which inherited the project after it acquired GBR Architects. Other firms involved include Crosier Kilgour as structural engineers, SMS as mechanical engineers, MCW/AGE as electrical engineers and Cochrane as civil engineers.

Gary Bolton, P.Eng., president of SMS Engineering of Winnipeg, was co-chair of the fundraising committee for the new building. The consulting engineering community contributed $1 million to the $56-million construction project.

FLOOD CONTROL

New Orleans levees structurally weak

A team of engineers and experts from the American Society of Civil Engineers and the University of California, Berkeley, has found structural problems helped cause the levee breaches in New Orleans during Hurricane Katrina on August 29.

The disaster flooded 75% of the city and caused 1,000 deaths approximately. Experts debate whether Hurricane Katrina was Category 3 or 4 when it hit New Orleans. The levee system was designed by the U.S. Army Corps of Engineers to withstand a Category 3 storm.

The preliminary report by the ASCE team found that the worst failures were in the eastern side of the city’s flood protection system, where storm surges reached 25 feet. When the water cascaded over the top of the concrete floodwalls along places like the 17th Street Canal, the earthen levees beneath began to erode. Levees constructed with inverted T-wall concrete cores proved more robust than those with I-wall cores.

The team found the floodwall was also weakened because of inconsistencies in the height of different concrete sections. Penetrations made for trains and roads to pass through the floodwall had made things worse. Another problem was the absence of access roads to reach the breach spots during the storm. The U.S. Army Corps of Engineers’ own standards recommend access roads along the top of floodwalls, but these had not been built in critical spots because of the dense urban context and need to acquire rights of way.

The expert investigating team suggested that the levee could have been strengthened relatively inexpensively with rip rap, concrete slabs etc. on the land sides.

The cost of rebuilding the floodwall to be able to withstand a Category 3 storm is expected to be US $1.6 billion. To upgrade the wall to withstand a Category 5 storm, which is what some are advocating, might cost US $3.5 billion.

In the first weeks after the catastrophe, a controversy arose over the awarding of large contracts to engineering companies without competitive bidding. Bechtel, CH2M Hill, Fluor and Shaw Group were given $100,000 contracts to rebuild temporary housing for the approximately 500,000 displaced residents of the city.

FLOOD CONTROL

Big dig begins in Winnipeg

Construction is under way on the $665-million expansion of the Red River Floodway in Winnipeg.

The project, being overseen by the specially created Manitoba Floodway Authority, is to widen the existing channel around the city to double its capacity and enable it to withstand a 1-in-700 year flood. The overall goal is to increase the flow capacity by 31,000 cubic feet per second. So large and extensive are the excavations, they are said to be roughly equivalent to those made to carve out the Suez Canal.

In September, crews began work on the embankment adjacent to the entrance to the channel at Grande Pointe. Work on widening the channel upstream was also due to start.

There have been substantial changes to the plans that were announced in 2003. Because of public concerns about the effect on groundwater, the channel won’t be made deeper, only wider. It will be made up to 130 metres wider than the existing channel in parts. And instead of submerged bridges, bridges with higher decks above the flood water line are now being designed.

Engineering design is all being done by companies in Manitoba, in two consortia. The contract for the main channel, structures and the west dyke is with KGS Group, Acres, SNC-Lavalin, UMA, Wardrop, Earth Tech, Barnes & Duncan, and First Canadian Engineers. The latter is an engineering firm representing First Nation communities.

The design contract for bridges and transportation engineering is with Dillon, Earth Tech, NDLea (now part of Marshall Macklin Monaghan), UMA, Wardrop, Barnes & Duncan and First Canadian Engineers. KGS Consulting was the lead consultant on the project definition and the environmental assessments. The environmental approvals were granted in July.

AWARDS

Schreyer winner announced

The winner of the 2005 Schreyer Award, the top technical award in the Canadian Consulting Engineering Awards, is the Ontario College of Art and Design, Sharp Centre for Design — Structural Engineering. The award was announced at a dinner at the Fairmont Chateau Laurier Hotel in Ottawa on November 23.

The award-winning consulting engineers are Carruthers & Wallace and MCW Consultants, both of Toronto.

The “Tabletop” structure is a dramatic two-storey block of studios and classrooms that floats 28 metres above the art college’s existing building on McCaul Street in downtown Toronto. The structure is partially supported by a set of splayed metal columns in bright colours. See page 31 in the October-November issue, where the project was published along with the other award-winners.

NOTES

B.C. Steel Awards

Winners in the B.C. Region Canadian Institute of Steel Construction Awards this year are the Varsity Village at the University of Cincinnati, by structural engineer THP; and the Watermark Restaurant on Kitts Beach, by structural engineer CY Loh Associates.

On the pill

Alberta Environment has found that rivers in the province contain traces
of drugs ranging from ibuprofen to birth control pills and steroids. Samples from water treatment plants at Edmonton, Calgary, Red Deer, Lethbridge and Medicine Hat all tested positive for pharmaceuticals.


Print this page

Related Stories

Leave a Reply

Your email address will not be published. Required fields are marked *

*