The Cochrane’s own lower end of a creek that doesn’t get much help or attention these days is Horse Creek. My travels have not included any trips to have a look at the Horse Creek Crossing on the railway tracks going out of the present-day town of Cochrane. However, Evan Martens was kind enough to send me a few photos of the site and it was really disappointing to see that the rail company has yet to resolve this issue, with the culvert that blocks fish migration upstream, including trout.
My attempts in the past, to get something done to resolve this matter involving the crossing were in vain, and I ended up being told by the rail company engineers that I would have to pay for the work that would involve replacing the culvert, which is ridiculous of course. All that was necessary was permission to modify the existing culvert and elevate the pool habitat directly below the crossing.
By simply elevating the pool habitat, the hydraulic drop would be eliminated and fish could migrate upstream. I have since, successfully completed the exact same project on a river crossing compensation contract, on the Athabasca River, so it does work!
The photo on the right shows a culvert that I worked on near the Athabasca River. The crossing bed and downstream outflow were created by my design ideas, while working with ATCO Pipelines engineers on the crossing design and enhancement work that BVHD completed.
The bed is comprised of boulder placements, held in place by a large cobble river rock, using a bed anchor design of mine called a cobble blanket anchor. The tightly fitted cobble is like a cobble stone road built in ancient Roman roads and highways, and it holds the larger boulders, which were also bedded into the substrate before the blanket anchor was built.
The project recieved my onsite oversight and with the good contractors crew, we had the project done and finished in no time. The main road was a major logging company road, with many thousands of dollars of timber and oilfield trucks that could not afford to be held up, so we did the job in a few days.
The trout need clear passage up small feeder streams that cross roads, so newer, modern design and implementation are the new order of things. When trout swim up a culvert, they need some current breaks to allow them to rest, and not expend too much energy trying to cross upstream. The rougher the bottom material, and larger, the more resistance that is created along the stream bed, which is called tractive force by hydrologists.
The roughness factor is a measurement of how much tractive force there is on a particular reach of stream channel. This roughness factor has been emulated with a number of different design approaches, but by keeping it natural, the chances of a blowout are low, if the desing criteria is followed.
The blanket anchor works as one cohesive unit when there is contact between the stones, during placement. This contact creates a solid mass of heavy stone weight that while placed securely on the bottom, is situated in a high velocity of flow, slowed thru the influences created by high tractive force.
There's much to see here. So, take your time, look around, and see how your ability to spot trout is.
Just a hint; The small trout cannot make the big water plunge, to pass upstream of this culvert.
The trout can't jump the drop of the culvert, so it cannot migrate upstream, like trout normally do by instinct. This and many other trout need a break, and a properly designed culvert will do the job!