Todd Cashin is the point man on just about every issue that has to do with the City of Kelowna’s natural amenities these days, but he started his career in forestry.
Stomping through the trees after flowing floodwaters ebbed taught him the inherent value of nature running its own course.
“Floods deposit silts, and that’s what makes the forest floor explode after every flood,” he said. “You’ll go in there and there will be vegetation like crazy.”
The wide variety of plants that sprout from the forest floor, in turn, attract a wide variety of species, creating what biologists call a “biodiversity hotspot.”
“They’re typically areas where there’s just a hell of a lot of critters and plants,” Cashin explained.
“It’s always on the edge of an ecosystem, where one moves into another.”
Such biodiversity—where reptiles, amphibians, bugs, birds and sometimes fish co-exist—isn’t easily found within the confines of an urban hub.
Kelowna, in particular, has seen a significant decline in amphibian, bird and reptile species, which over time have gone from bountiful to at-risk, in tandem with human populations growing.
Like other cities across Canada, Kelowna has built up its infrastructure to accommodate the needs of swelling communities.
So the powers that be in those years tended to pave, flatten or, as was the case with Mission Creek—a waterway soon to get a new lease—dike all that was around.
“With the dikes, they were engineered perfectly to move the water along to provide as much agricultural land as you possibly can,” said Cashin.
“The problem with that is biodiversity decreases, the risk of flooding increases, sedimentation increases, water quality decreases.”
By returning some of the natural flow to Mission Creek, like what happens in the forest floor, many of the aforementioned problems could be eliminated, Cashin believes.
“Everything I’m trying to do relates to what I learned in the bush,” he said. “There’s nothing better than knowing where all the creeks are and trying to fix the places where there are problems and protect the areas that don’t need anything.”
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Mission Creek has long been identified as one of the areas that needed some fixing.
Plans to rehabilitate what was lost when diking began in the 1930s got underway in the ‘90s, and every level of government along with a number of special interest groups have chipped in on efforts to make improvements.
The most comprehensive look may have started with the Okanagan Lake Action Plan.
“It asked, ‘How do we make things better for kokanee and rainbow trout?’” explained Cashin.
“They identified in-lake and out-of-lake issues, and Mission Creek was important for how much water it provides to the lake and how much spawning goes on in there.”
Restoration projects may have started out “fish-centric,” but Mother Nature and changing societal values have added a few twists to their trajectory.
“Now there are recreational and aesthetic values on the social side and there are species at risk to think about,” he said.
“It’s a jewel of a corridor that runs right through the agricultural and urban environment and that’s where all the species at risk tend to flock.”
As was the case when the dikes came in all those years ago, there are still flooding concerns.
The difference between now and then, however, is the change in the way floods happen.
“The hydrograph has changed. The Okanagan is not expecting to see more precipitation, but we’re expecting to see more precipitation fall as rain, and less as snow,” said Cashin.
With water flows being so significantly altered, new needs at different times have arisen, but all the channel that currently exists knows is the previous flow regime.
Working with what nature is giving them, and creating more room for that water to go, may be the best way forward—thus the plans for the city to soak up more land.
Council recently unanimously endorsed plans to buy a four-acre property west of Swamp Road, immediately south of Mission Creek.
Pending approval from the provincial Agricultural Land Commission, the property could be converted from farmland to wetland, subject to seasonal flooding.
“I think it’s a beautiful piece of work many years in the making,” said Coun. Luke Stack, when the issue was raised at a council meeting.
“This is actually one of my favourite projects because it’s a win-win on so many levels,” added Coun. Gail Given.
Between the recently approved purchase, another seven acres already bought from the Casorso family and a chunk of property in the Mission Rec plot, there’s roughly 15 acres between Casorso Road and Gordon Drive that could be used to direct the creek to its original course and restore much of the life that’s been lost.
Cashin has reluctantly become the face of this leg of the creek restoration, but he stressed he’s far from the only one who has had a hand in bringing the project to life.
Don Dobson, now with Urban Systems but previously with the provincial government, has been working on Mission Creek in some form since the 1980s.
Given his expertise and long relationship with the waterway, Dobson was recently tapped to help fourth year UBC Okanagan engineering students Jacob Paul, Dylan deSousa and Jordan Beach create plans for reshaping the space.
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If a person were to stand on Gordon Drive Bridge and face toward Casorso Drive Bridge, they’d see a straight stretch of water flowing in between the two.
It’s not the natural flow of the river, but perfectly encapsulates what’s happened to the full span of Mission Creek since settlement. “If you measure the length of all the river channels on Mission Creek, starting from East Kelowna and ending on Okanagan Lake, and compare what they were before diking and what they are today, there have been a lot of changes,” Dobson explained.
“Somewhere in the neighbourhood of 30 to 35 km of channels existed before dikes, now the channel is 11 km long.”
The land that’s been purchased between the two bridges won’t bring back all that lost length, but it will help improve the ecology of the area—changes Dobson has seen work in the past.
In the South Okanagan, he was a key figure in the Okanagan River channel restoration project, which has been lauded for bringing back much needed biodiversity to the area.
In that project, they pulled the dike out, put rocks in the channel to cause diversions, dug out a couple of pits to attract salamanders and spadefoot toads, and created a new place for endangered species to flourish.
“When I was asked to work with the (UBC Engineering) students, I was more than happy to provide any of the coaching and guidance required to allow them to decide where the alignment would go, what the volumes and materials would be and what the design would be,” he said.
There are three options at play, currently. “One is status quo, leave it alone,” he said. The other two options have to do with altering the dike.
Dobson’s preferred option is to reduce the dike down to the natural ground level, then allow the creek, as it rises during spring freshet, to gradually create its own channels through the expanded area that’s been acquired by the city. In some stretches that could be a 30-metre meander and in others 80 metres.
“Creeks love to meander,” Dobson said. “If you ever play around with water, or look on Google Earth, you very seldom find a straight line of creek; it wanders and curves.
“So, if we were to do that to Mission Creek and remove all the dikes from where they are alongside the creek and set them back 200 to 300 metres, the creek would start to meander back and forth, creating new channels that will wind through the area, creating more wetlands, habitat and so forth.”
The next option is to build a new dike and cut a series of openings through the old one so water can flow through the gaps into the expanded area. During higher flows, water would move into the area and create wetlands and habitat, and then the rainbow trout and kokanee have a place to rest and feed.
“Regardless of what you did, whether you remove dikes or open it up so the land in behind was allowed to become wet, you are going to create a whole variety of habitat,” said Dobson, noting that there’s enough material in the existing dike to build a new one.
The new view from Casorso bridge in the future won’t be nearly as linear once the plan is put in place. Instead of a half-kilometre of “dead channel,” the waterway could just curve left, move out into the new area, where the existing dike is.
“You will get a whole complexity of habitat, with channels that flow all year, high water channels, pools and wetlands,” he said.
It’s unclear as yet what option will be chosen, as the proposal will be reviewed first at the university level, then the city and finally by the provincial government and its Department of Fisheries and Oceans. “The approval process will involve basically the province from a flood control perspective and fisheries perspective,” he said.
Regardless of what plan is put into motion, Dobson said it could be a step in the direction of a larger restoration plan.
“This is tremendous,” he said. “There are still agricultural lands along the creek, and if the city was able to show how successful this one was, then it encourages the province and other private funding agencies to step up and offer to invest funds to purchase some additional lands. “
The wider the Mission corridor can be made, he said, the better it is because more of the natural functions of the creek can be restored. “Whether that’s fish habitat, fauna and flora, ecosystem values and flooding; natural systems allowed to operate in a normal way are much less expensive and of much more value to society,” said Dobson.
