Fish passage technology in the river Teme
Meeting Chris Bainger & Charles Grundwell
It was morning when I met Chris Bainger, fisheries technical specialist in Environment Agency. He was kind enough to pick me up at the campsite I was staying and show me the river Teme.
In the next stop I met Charles Grundwell, senior fisheries specialist in the Environment Agency’s national team. Both showed me around that day show me fish pass technology through the ages.
Then we walked to the oldest (and maybe they biggest reminder how not to build a fish passage) that the river Teme had the offer. Built a few decades ago the fish pass stood the test of time but now it is a bit of an eye sore for those that have more recent knowledge of fish pass development.
This dam was previous a hard obstruction for salmonid fish migration. Salmon swims with the streams in search of a strong stream. If it can find one, he pokes his head out of the water and looks for white water. Jumping towards the white water, expecting a pool to land in and repeat the process again. But in at this weir the salmon pokes his head out of the water, looks up and jumps. Only to find a concrete slap to smash into and be pushed back by the water in the river once again and again and again. The reason why this dam needed a fish passage was obvious. But back then it was less obvious how fish find a fish passage. So they make and designed the fish passage in the middle of the weir. On the picture you can see this really well because over the past months Europe had a dry spell. In England is normal to have two days of summer and then it start to rain again. Now all the weirs where dried up. So the situation with the fish passage is as followed: The weir is normally covered in water, so much that the salmon are not attracted to the fish passage ‘attraction flow’ but are drawn to the weir itself. So salmon still tries to jump the weir however after failing multiple times they eventually find the fish passage.
After that we drove to a beautiful estate. The owner of the Estate had made a hydro-power scheme and was required to place a fish passage so that the fish had no problem to find its way without being shopped to pieces. The result is this beautiful prestige weir with ample room for fish to move up and down river. The lesson what we can learn from this fish passage is that the fish passage should be on the other side of the weir where fish notice the attraction stream more easily.
After seeing this beautiful estate we went to another pristine river sight and a prime example why people like their weirs so much. We grabbed our lunch boxes and had a lunch on the dried up weir. This dry spell was not good for the river but showed me a unique perspective on how a weir is made and that was quite interesting. Charless mentioned during this break something really noteworthy. Baseline biased, this mean people only want to be restore something like it used to be in their perspective/lifetime. So this site where we were on at the moment was protected by different organisations because this is wat people knew as pure England beauty (within their perspective). Altering this sight to a free-flowing river is thus, a real no go.
We drove off to the more rural parts of the river. This part of the river did not have weirs or any alteration into the river itself. Chris however told me that he saw how the river was changed due to the field around it. He told me an extraordinary story that I never could have guessed that it could alter the river coarse. This story is connect to cricket. Cricket is England’s most famous sport beside football. This story is not about the game but about the bat. The bat is made of willow wood. Those threes that are a true pleasure to the eye because you can always find them hanging over water. The willow threes need a lot of water every day. Because the cricket bat is made out of willow wood, such a tree can fetch a hefty price on the wood-market. So much that when a farmer gets a daughter he plants a willow three. When the daughter comes of age of marriage he chops down the willow three and sell it to pay for her wedding. However this means that planting more threes means more profit and when this happened you can see it in the river. The river has less water changing the morphology of the land. The rural part of the river we where was completely dry not only because of the dry spell but also because of the nearby willow threes.
Moving on a bit further down the river, was a fish passage that was pool based. Worked like a charm.
The final destination was a yet again a bit of dried up river where the fish lived in small pool due to the dry spell.