McGill engineering teacher proposes faster, lighter method of channeling floodwaters

CTV Montreal: New flood relief method A McGill engineering teacher believes he has a better, faster way to contain rivers and prevent floods.

Municipalities in low-lying areas across Quebec have already begun stockpiling plastic bags and piles of sand in case of flooding this spring but a mechanical engineering teacher at McGill University believes he has a better, faster way to contain rivers and prevent neighbourhoods from being flooded.

Amar Sabih is testing a system that involves plastic sheeting similar to what is used in above-ground pools, backed by metal barriers.

He said that it could work just as effectively as sandbags, if not better, but be installed with much less labour.

"What you need [is] to make a structure [on the] your side of the house, on the other side of the street and you put similar material to what you use in the swimming pool but you just send it to the street," said Sabih. "Then the good thing about this material is it is very flexible so it will take all the shape of the street, the sidewalk, whatever there, and when the water of the flood arrive there and come on top of it, it will exert enough force to keep it in position."

Similar products have been tried or are on the market, but Sabih said while the material may be expensive, governments could find it less expensive than buying sand and bags which cannot be reused.

"It has been used by other companies that are mostly bankrupt because no one is willing to pay USD$400 for one metre," said Sabih.

He said one advantage of his proposal is that could employ metal barriers that are already used by municipalities for crowd control.

A second advantage is speed, and Sabih demonstrated setting up a portable dike about 10 metres wide in a matter of minutes by unrolling a tarp over a barrier, tying it in place, and then placing weights on the structure to hold it in place while the water rises.

Building a wall that long by piling sandbags could easily take one person more than one hour.

"Last year one of my students told me that she volunteered to build some sandbag barriers to fight the flood. She told me we spent all day, 60 or 40 people, just to save one house," said Sabih.

Not only is his system faster to set up, it requires lighter materials that are much more portable.

"If you take sandbags in one truck you'll save two houses maybe, but this will save about 30 houses," in the same amount of space, said Sabih.