A River Condition Assessment (RCA) uses a combination of a ‘river type’ desk study and field-based survey, known as the Modular River Physical (MoRPh) survey, to evaluate the condition of a watercourse. MoRPH surveys involve looking at short sections of the river, called modules, and recording sediments, physical habitats, vegetation structure and human pressures and interventions across the bank tops, bank faces and bed within each module.
The assessment of the condition of a river or stream can be used to inform Biodiversity Net Gain calculations and river restoration techniques.
Biodiversity Net Gain
Biodiversity Net Gain (BNG) ensures that a development will improve the biodiversity of a site by at least 10%. If a river or stream lies either inside or within 10 m of the red line boundary of a development (from the bank tops), it will need to be considered in a development’s BNG calculation. Canals, ditches and culverts need to be included where they are located within 5m of the red line boundary.
To inform BNG calculations using the Statutory Metric, an RCA will be required. This can only be undertaken by certified individuals.
RCAs should be undertaken in spring or early summer during periods of low flow and when vegetation is not so high as to obscure the physical features of the watercourse.
Key Benefits of Service
- Establish baseline conditions of watercourse habitats for Biodiversity Net Gain calculations
- Identify enhancement opportunities
- River Condition Assessments are undertaken by our certified staff members
