It should be possible to manage the waters of the River Sid in a more sympathetic way.
A current project is the creation of ‘leaky dams’ near the source of the river:
Further work with the Leaky Dams at Stoney Orchard Growing Community in the woodland will continue in September. The rain in July and August has very much helped what we have done so far to establish itself.
We were behaving very much like beavers in the spring, making sure vegetation and mud was squished, as we progessed with the dam, adding willow sticks and sedge plants, both of which are growing brilliantly. If you would like to come and learn and have hands on experiences. Let us know!
(20+) Sid Valley Biodiversity Group | Facebook
The Herald has just published a piece on the project:
Leaking dams for flooding control | Sidmouth Herald
Which is very similar to what was practiced some time ago on the river:
Furze weirs along the Sid – The Sid
Meanwhile in Cornwall…

The volunteers created a barrier of willow and hazel branches to strengthen the bank of the River Hayle, near St Erth. The result was a natural barrier that protects the path and the wildlife from the waters, project leaders said.
“This green method is better for the environment and cheaper than concrete, and anyone can learn how to do it.”
St Erth: Volunteers branch out to restore eroded river bank – BBC News
And there are lots of ideas out there for ‘green infrastructure’:
5 Easy Ways to Revive Your River: Support… | The Rivers Trust
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