A framework for managing runoff and pollution in the rural landscape using a Catchment Systems Engineering approach

Area of Science:

• Environmental Engineering
• Hydrology
• Agricultural Science

Background:

• Intense farming practices increase local runoff and erosion, leading to water quality degradation and flooding.
• Agricultural management offers potential solutions for controlling catchment-scale runoff.
• Catchment Systems Engineering (CSE) provides an interventionist strategy to modify runoff regimes by manipulating hydrological flow pathways.

Purpose of the Study:

• To explore the application of a CSE approach to manage catchment-scale runoff and associated environmental issues.
• To implement and evaluate Runoff Attenuation Features (RAFs) for mitigating diffuse pollution and flooding.
• To present a framework for applying CSE strategies through stakeholder engagement and field science.

Main Methods:

• Implementation of various RAFs, including bunds, diversion structures, large wood debris, and riparian zone management, within the Belford catchment.
• A step-by-step framework guiding the application of CSE mitigation measures.
• Monitoring and evaluation of RAF performance in altering runoff regimes and reducing pollutant losses.

Main Results:

• The CSE approach successfully altered the runoff regime at the catchment scale, addressing flooding issues.
• Initial findings indicate that implemented RAFs effectively reduced local runoff.
• Modifications and new RAFs are suggested for improved diffuse pollution control, with initial results showing enhanced sediment trapping and reduced nutrient and suspended sediment losses during storm events.

Conclusions:

• The CSE approach, utilizing RAFs, is a viable strategy for managing agricultural runoff, flooding, and diffuse pollution.
• Stakeholder engagement and adaptive management are crucial for successful CSE implementation.
• Modified RAFs demonstrate improved effectiveness in reducing nutrient and sediment losses, highlighting the potential for enhanced water quality in agricultural catchments.