Making leaky dams - Video

Back in another lovely woodland last week, this time beavering away making leaky dams and other woody natural flood management features for Sussex Flow Initiative. Natural flood management helps to reduce flooding by working with natural processes, slowing the flow of streams and rivers and increasing storage capacity upstream to prevent flooding further downstream. This also has the added benefits of creating habitat for countless water loving species and helping nature to recover in riparian areas.

Leaky dams are basically woody obstructions placed in streams and rivers, forcing water out of main channels and onto floodplains, creating pools and reducing the velocity of the water as it travels downstream during flood events. There are lots of different types of dam, some more elaborate than others and each intended to interact with the flow in specific ways but all are designed to kickstart natural processes and mimic naturally occurring obstructions; the kind we have been mistakenly removing from our waterways for many years. Over time the dams we make catch leaves, sticks and sediment drifting downstream and become more effective. Some are made from medium sized trees cut to length, hammered and staked into place, some are brash bundles laid in parallel with the flow and others are simply large trees felled directly into or across waterways.

Having to think about how water interacts with the land, and working with natural processes made this one of my favourite conservation projects to work on. There’s also no denying that messing around in streams pretending to be a beaver is a lot of fun.