Minn’s Meadow – putting the gravel back

Minn’s Meadow was our attempt at finding a way of properly fixing the dredged parts of the river. Because dredging is the most fundamental and widespread way in which chalk-streams have been damaged, I’m really interested in what we can do about it.

Here we have taken the gravel from borrow-pits beside the river and restored long riffles in sync with the meander pattern of the river. The borrow pits were filled back in and have settled into flood-plain hollows that imitate old oxbows and have a nice side-benefit of wetland habitat. There were quite a few snipe hanging around them in the winter.

It was also nice to see that the riffles were used by spawning trout (and sea-trout) within a month of going in. I feel the fact that the gravel was ungraded and from the floodplain beside the river might well have influenced how readily it was adopted by spawning trout.

Here’s a few before, during and after photos. Before we started all the gradient in this meadow was lost over the first few yards, whereafter the river was deep and sluggish. Now we have spaced the gradient out of a series of riffles with natural shapes and spacings. It is great to see patches of ranunculus growing where there was only eel-grass.

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Here the channel is too wide and deep. The bed is silty and supports mostly eel-grass.
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We filled the channel in with a long riffle (half-a-meter depth of infill) and afterwards narrowed with plugs of canary sweet-grass taken from the meadow.
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Six months on, the banks are recovering, the gravel is clean and we have ranunculus and starwort.
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The same reach as above but looking from the top down. Total project length was 650 meters.
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Immediately after.
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Six months on.
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This was taken last autumn after we cut through the burr-reed to release the flow. Before that the channel was invisible!
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The same reach after the gravel went in. A large sea trout spawned here a few weeks later.
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The same reach in May this year. A much shallower and tighter channel will keep the burr reed to the edges and support ranunculus – which is starting to appear in patches.

 

 

 

 

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