Client: Natural England
Partners: Nutrient Neutral, Wetland Engineering, Practical Ecology
Location: Fakenham, Norfolk
Overview
In response to ongoing nutrient pollution in the Wensum and Yare river catchments, Natural England is working closely with landowners and technical partners to explore nature-based solutions (NbS). The goal is to reduce nutrient loads, generate nutrient credits, and deliver broader environmental benefits through the implementation of constructed wetlands in strategic locations.
To support this initiative, H Fraser Consulting – alongside Nutrient Neutral, Wetland Engineering, and Practical Ecology – was engaged to carry out a comprehensive feasibility assessment of two proposed wetland sites: Fakenham East and Fakenham South, near Pensthorpe Natural Park.
Project Scope
This assessment aimed to determine the technical viability and environmental suitability of the two sites for constructed wetland implementation and nutrient credit generation. The findings would help guide investment decisions and future design and development.
Our Methodology
1. Desk Study & Site Investigation
Initial research and field surveys were carried out to understand topography, existing drainage, soil types, and land use.
2. Influent Flow Analysis
Estimated incoming water volumes and nutrient concentrations to evaluate the nutrient removal capacity of potential wetlands.
3. Modelling & Design Simulation
Simulated nutrient reduction scenarios using sensitivity analyses to understand performance under variable conditions.
4. Risk & Constraint Assessment
Assessed potential challenges related to biodiversity, soil stability, archaeology, existing utilities, and risks from urban runoff.
5. Monitoring Strategy
Outlined a monitoring framework for baseline and ongoing data collection, ensuring adaptive management and compliance.
6. Cost Estimation
Produced detailed financial projections to support investment decisions and compare site-specific costs.
7. Feasibility Assessment Report
Delivered a comprehensive report with findings, constraints, and recommendations for future development phases.
Key Insights & Recommendations
- Hydrology & Water Balance: Both sites demonstrated the capacity to support wetland conditions year-round, including during drought periods.
- Soil Conditions: Hydraulic conductivity levels confirmed the potential to maintain adequate water retention for nutrient removal.
- Ecological Review: Initial appraisals identified no major ecological constraints; however, further species-specific monitoring was recommended.
- Nutrient Capture Uncertainty: Variability in influent nutrient concentrations resulted in up to 50% uncertainty in nutrient removal projections, underlining the need for additional data before progressing to detailed design.
- Site Comparison:
- Fakenham East: Strong candidate for wetland development based on flow availability and lower ecological risk.
- Fakenham South: Requires further hydrological and ecological assessment to confirm suitability.
Conclusion
This feasibility study provided essential insight into how nature-based solutions can support nutrient mitigation efforts in the Norfolk river catchments. The collaboration between HFCL and its partners ensured a holistic, multidisciplinary evaluation that balanced technical feasibility with ecological and regulatory considerations.
The findings support the next phase of detailed design and implementation, contributing to sustainable catchment management and ecological resilience in the region.
Looking to implement nature-based solutions or assess wetland feasibility?
Contact us to learn more about our expertise in hydrogeological assessment and nature-based solutions for nutrleint management.
