The Wye and Usk Foundation’s Yazor Natural Flood Management Project

Two linked projects are currently happening on the Yazor Brooks: downstream, in the City, our Yazor Brooks Restoration Project is improving habitats and engaging local communities while upstream, the Wye and Usk Foundation (WUF) are leading on Natural Flood Management. Lucinda Lewis from WUF tells us more...

Previous flood defence schemes in the Yazor catchment have involved large-scale, hard engineered solutions. However, these approaches are costly and there is increasing evidence that demonstrates that small tweaks to the management of the wider countryside, known as natural flood management (NFM), can also help to reduce flood risk to downstream properties.

Rivers are the pathway for flooding, but the surrounding catchment is where the majority of rain falls and where runoff can be generated.

In Herefordshire several watercourses have been identified as a priority for NFM due to the number of properties that suffer from flooding directly downstream; the Yazor Brook is one of these. The approach for this NFM project, unlike many others in the UK, seeks to identify opportunities for agricultural land that can:

  • increase water infiltration rates
  • increase water holding capacity of soils
  • reduce runoff and soil loss
  • improve condition of stream banks and bankside vegetation to increase channel roughness
  • slowing the flow of water in the brook itself through introducing leaky dam structures or planting hedges and trees

Actioning these across the catchment will slow the flow of water into the river system at times of high rainfall without compromising agricultural activities.

Farmers and landowners in the upper catchment are working to help reduce the flood risk to downstream properties. They are changing soil management to improve water infiltration and testing organic matter levels to ascertain water holding capacity.

Cropping patterns are being changed to improve the soils capacity to hold water.

The practice of multi-species cover cropping is one management practice being adopted by farmers in the catchment. This crop is planted straight after the main cereal harvest to create thick ground cover with a variety of rooting depths and habits to improve soil structure, put organic matter deep into the ground and to prevent rapid run off of rainfall by increasing infiltration capacity. The cover crop is then destroyed prior to the planting of a spring crop.

Root crop amongst vegetation
Arable field covered with a green crop
Grassy field edge

Planting wide rough grass margins to slow the flow of water from farmland is also being carried out.

Map with area highlighted in blue

Soil health improvements are being encouraged throughout the catchment. Key sites are identified from Scimaps and detailed soil assessments.

Grassland management is important to ensure maximum rainfall infiltration within a catchment. Well managed swards have the capacity to capture carbon from the atmosphere and hold it in the form of organic matter which acts as a sponge for rainfall. Run off is also slowed by dense rough grass swards

A fell tree holding back water within a woodland

In woodland areas leaky dams have been installed to slow run off rates.