Our work to look after Cotehele Mill

Looking after the Morden Weir

Torrential rain and flooding destroyed the weir on the Morden stream in late 2020. The weir was over 200 years old and actd as a barrier to direct water through the leat to Cotehele Mill where it turned the wheel.

Over the following years, we’ve been looking at options to reinstate the weir and carried out extensive work and surveys to find a way to do this that meets modern standards. Part of this included needing to undertake DNA sampling of the stream to prove that fish species such as Allis Shad and European Smelt were not present this far up the stream. In Summer 2023 we commenced DNA sampling for twelve months and had very inconclusive results. We’re not too sure why, but it’s likely due to water quality issues from the stream’s mining past meant that sampling couldn’t work.

Due to these inconclusive results, we paused the project to allow us to consider the habitat of the river, the impact of a new build structure within the natural environment, the impact continuing to gain inconclusive results and the risks of permission not being approved, the buildability, carbon costs, as well as the future sustainability of the structure, we have decided to end this project due to the increased risks involved. Although this project has now ended we are still committed to run the mill for demonstration and milling purposes, but powered in a different way.

What’s happening now at the weir?

We’re now starting work to improve the stream habitats for wildlife, this includes some landscaping works to improve the appearance of the bankside at the weir.