Sunday, January 26th 2020, 6:14 pm - The recent heavy rainfall in British Columbia contributed to this striking scene.
The heavy rainfall from the recent storms in B.C. created a striking scene on Vancouver Island that Michael Hack discovered with his drone. The convergence of the Quinsam and Campbell River created a stark colour difference that was caused by the variation in sediment being carried by the two rivers.
"I took this from a drone after recent storms bought significant rainfall to the island. I have seen this here before after other large rainstorms, but never had a chance to catch it from this perspective. This spot is a popular fishing spot for locals as the Quinsam has a significant salmon return each year," says Hack.
THE SCIENCE BEHIND
Parts of Vancouver Island have recorded over half a metre of rainfall so far in January, which is a significant amount, even by B.C's wet standards. But, there are notable differences in these two rivers.
Highlighted in red below, the Quinsam River is a highly meandering river – cutting and carving new paths through the region. These rivers are excellent at transporting sediment, as the individual meanders grow through time.
Generally speaking, the greater the water flow, the higher the sediment load. Heavy rainfall picks up sediment, creating significant runoff.
On the other hand, the Campbell River is highly regulated by a series of hydroelectric dams. These dams limit the amount of sediment that is suspended in the river, as deposition tends to occur before each of the three dams in the series along the river.
By this logic, I think you could guess which source the City of Campbell River has chosen for its drinking water...the Campbell River, of course.
TOO STRAIGHT TO BE TRUE?
Here is a good rule of thumb: If a river looks too straight, it probably is.
Natural rivers tend to organically carve new paths, while an artificial one is often forced to travel along a straight line with artificial embankments and other manmade structures.
Footage courtesy: Michael Hack (@michaelrhack on Instagram).