INNOVATION November-December 2017

Residents of Kimberley enjoying the recreational opportunities offered by the restoration of Mark Creek. P hoto : C ori B arraclough .

bed, and replacing it with a far safer and longer-lasting structure made up of locally sourced rounded river rock and large boulders that would also look more like a natural stream channel. The team also proposed widening the creek to deal with two major issues. First, detailed hydrological modeling showed the channel could contain the 200-year clear water flood level required by the Province, but with a far-too-fast average velocity of 16 metres per second; and second, because the lower part of the creek sits on an alluvial fan, repeated debris floods were a distinct possibility. “We had to find a way to flatten the channel gradient to slow the speed of the flow and make the creek safe, and that meant making it wider,” LaCas says. In addition, because one of the key issues (other than human safety) with the old flume was loss of aquatic habitat, particularly for the endangered Westslope Cutthroat Trout, the team also proposed methods, such as a series of deep ponds, u-shaped weirs, riffles and waterfalls, as well as underwater rock and log habitat clusters, for dissipating energy, encouraging new fish habitat, and restoring the ecological function of the creek. It was a complex and somewhat contentious project proposal, with some residents objecting to what they could see would be a hefty price tag for a small town plus the loss of some buildings, but the city council bought into it, even going so far as to start the project without knowing what the overall cost would be and without provincial or federal government funding. “I was proud of the way council handled this,” says Fox. “They put public safety first and saw the vision of what the creek could be.” In the end, the city took down three vehicle bridges and completed land negotiations with four homeowners,

AYEAR can CHANGE EVERYTHING

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