charles rangeley-wilson – writing about fishing, travel, rivers, conservation

Putting the Gravel Back

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Minn’s Meadow was our first real attempt at finding a way of properly fixing the dredged parts of this little chalk-stream. 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.

The problem is, putting gravel back is very expensive … if you import it from off-site.

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 80% of the fall in this meadow was lost over the first few yards, whereafter the river became deep and sluggish. Now, we have spaced the fall out over a series of riffles with natural shapes and intervals.

It is great to see patches of ranunculus growing over bright gravel where before there was mostly silt and eel-grass. And there are trout everywhere!

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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. 

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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.

2 Responses to “Putting the Gravel Back”

  1. rangeley

    Andy, no it isn’t just you! A technical glitch which I am just trying to fix. Apologies and thanks for the heads up. Charles.

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