Lake By-pass in Hertfordshire

Online lakes have a significant impact on natural river processes, changing sediment transport, flow dynamics and water quality. Salix were involved in a lake bypass project on the River Beam, to restore natural river process and ecological enhancements.

Salix were involved in a recent river diversion on the River Beam in Hertfordshire, to improve hydromophological and ecological function.

Online lakes significantly reduce flow velocities, causing sediment deposition and subsequently impact on water quality. In this instance, a weir was also impounding this section, limiting fish passage.

Salix created a bypass channel in August to reconnect fish populations and restore natural function to this section of river. Increasing flow velocities assists with the suspension of sediment, which subsequently reduces the risk of gravel smothering.

River diversion on the River Beam

River diversion on the River Beam

Gravel is required by specific fish species to lay eggs in well-oxygenated water. Since completion, vegetation rapidly established over the site, including marginal species self-seeded from upstream.

This section of watercourse will now provide excellent ecological value in conjunction with the lake habitat.