Project objectives

  • Build and monitor RAIFs to generate robust evidence of their benefits for water resources.
  • Validate the EA’s latest groundwater recharge mapping and modelling for chalk river catchments.
  • Provide actionable insights into implementing NbS including landowner engagement, permitting processes and cost analysis.

Why RAIFs?

Using the EA’s groundwater recharge mapping and modelling, these features were identified as the most effective NbS for chalk catchments, offering a balance between amount of land required and potential for aquifer recharge.

 

Wensum NbS Trials

  • In 2025, Norfolk Rivers Trust led a consortium of delivery organisations to design and construct the feature, and install monitoring equipment.
  • The RAIF is a large permeable basin located at the edge of a field in the catchment.

Cam NbS Trials

  • RAIFs have been established at three sites across the catchment, consisting of a series of wooden leaky dams installed within existing farm ditches.
  • To ensure robustness of the evidence base, additional RAIFs will be installed at two further sites in 2027.

Our Senior Research Associate, with support from the University of East Anglia, is responsible for collecting data on a monthly basis. The data will be analysed and reported annually.

Strategic importance 

These sister projects aim to build a national evidence base for chalk catchments, informing future strategies like the Water Industry National Environment Programme (WINEP). By validating modelling results and gathering real-world data, we can demonstrate the value of NbS and provide a pathway for scaling up these features across the region. 

EA logo 377U
WWF FINISH SHARED WORLD

Project foundations

The mapping and modelling work which preceded the NbS Trials was delivered by JBA Ltd. and was commissioned and funded by the Environment Agency. You can view the reports under this licence: Open Government Licence.

Stage 1 – Quantifying the Water Resources Impacts of Nature-based Solutions in the:

Stage 2 – Quantifying the Water Resources impacts of Groundwater and Nature-based Solutions in the: