Much of Chiddingly Parish lies within the catchment of the Bull River, one of the main tributaries of the Cuckmere River. Due to its underlying geology, river levels in the Bull can rise rapidly during heavy rainfall events, contributing to flooding downstream in Hellingly and Hailsham. This page provides information about Greening Chiddingly projects that are using natural flood management approaches to slow the flow of floodwater into the Bull River and create new wetland habitats.

Installing leaky woody dams

Two of our projects involve the installation of leaky woody dam structures across gullies and waterways. These are, in their simplest form, felled trees that are laid across a watercourse and held in place by natural anchors. In time, the low dams trap sediment and pond back the stream water. In this way, the passage of water is slowed and flood peaks reduced during periods of heavy rainfall. The areas immediately upstream of each dam develop into new wetland habitats, providing new spawning grounds for insects and increasing the length of the breeding season for amphibians. The photos below show the initial stages of construction of nine leaky woody dams in a wooded gully on Peke's Farm.

Lowering a tree trunk into place to create a leaky woody dam structure on Peke's Farm. Note the use of local trees to create the dam. Image: © Dean Morrison.

Trimming stakes to support a leaky woody dam structure across a boggy gully bottom on Peke's Farm. Image: © Neil Burfield.

Water beginning to pond upstream of a recently installed leaky woody dam on Peke's Farm. Image: © Neil Burfield.

Water starting to pond upstream of a leaky woody dam on Peke's Farm, creating new habitat for amphibians. Image: © Neil Burfield.