Unlike Biodiversity Net Gain (BNG), which applies universally across England, Nutrient Neutrality regulations are highly region-specific, targeting areas where waterways are at severe ecological risk.
This case study examines how BNG Partnership handles strict phosphate mitigation requirements within Somerset, specifically inside the Brue & Axe operational catchment. By working in collaboration with Somerset Council and housing association Aster Group, the team unlocked the planning path for 33 vital affordable homes.
Central to this success is BNG Partnership's Manor Farm Phosphate Mitigation Scheme in Prestleigh, which permanently resolved the nutrient deficit. With all approvals now fully complete, Aster Group is officially ready to break ground on site, proving that environmental compliance and community growth can progress together.
In Somerset, the primary environmental constraint is phosphate pollution affecting the Somerset Levels. The local water system is divided into distinct operational catchments where all regional waterways feed:
Because the Aster Group development site sits directly within the Brue & Axe catchment area, the plans for the 33 affordable homes triggered mandatory nutrient mitigation. Without a viable offsetting strategy, the delivery of these essential social rent and shared ownership properties faced an indefinite planning block.
To clear the planning hurdle, Aster used Natural England’s official Phosphate Budget Calculator. This tool determines the exact impact of a proposed development based on its size and occupancy, calculating the precise amount of phosphates (measured in kilograms) that the project needs to offset.
Once the exact kilogram deficit was established, BNG Partnership provided the necessary offset within the Brue & Axe catchment area. This ensured that any nutrients added by the new residential homes were entirely counterbalanced by strategic environmental interventions elsewhere in the same catchment.
With the mitigation strategy secured via Manor Farm, the final planning obstacles have been cleared. Somerset Council has granted full approval, meaning Aster Group is now ready to break ground and begin construction on these much-needed homes.
Paul Backhouse, Assistant Development Director at Aster Group, commented on the success of the project:
“Nutrient neutrality is a complex part of delivering new housing. For the Cemetery Lane site, we secured a phosphate mitigation solution within the Brue & Axe catchment, enabling the planning condition to be discharged and the scheme to move forward with 33 much-needed new affordable homes for the local community.”
