Nutrient Neutrality January 2025
What is Nutrient Neutrality?
All local planning authorities in Norfolk received a letter on 16 March 2022 from Natural England about nutrient pollution in the protected habitats of the River Wensum Special Area of Conservation and the Broads Special Area of Conservation and Ramsar site.
The map above shows the areas effected which effectively put a hold on all new housing in these areas. This includes:
new homes
student accommodation
care homes
tourism attractions
tourist accommodation
permitted development (which gives rise to new overnight accommodation) under the Town and Country Planning (General Permitted Development) (England) Order 2015
any development not involving overnight accommodation, but which may have non-sewerage water quality implications
Natural England’s aim with this moratorium on planning approvals is to attempt to prevent further nitrogen and phosphate pollution in the catchment areas.
What are the pollution sources?
Royal Haskoning presented two telling pie charts which are repeated here indicating the source of pollution within the two catchment areas. As can be seen urban only accounts for 18% and 7% of the total pollution in the area. The main contributors are Anglian Water (STW sewage treatment works), livestock and agriculture.
Central Government research also indicates agricultural run-off and the inaction of water companies to maintain infrastructure, resulting in them having to discharge raw sewage into our rivers, to be the overwhelming causes of the nutrient neutrality issue.
Despite this Water Companies have been given until 2030 to upgrade treatment works to the minimum required levels. No action has been undertaken to address the agricutraly run off levels.
What solutions are available?
Nutrient Credit Schemes
Currently Norfolk Environment Credits acting as a broker can provide credits for the following catchments:
Wensum
Yare
The follow catchments is still awaiting credits
Bure
Permeant credits are currently priced at £5,900+VAT. These costs are for 0.1kg/yr Total Phosphorus. Each development will require its total Phosphorus run-off calculated with with the Natural England Calculator or the Norfolk catchment Calculator.
Alternative credit providers are also working towards creation of credits such as Wendling Beck for the Wensum Catchment but to date these are not available.
Developer Mitigation
Developers may be able to create there own mitigation through several methods. The most common is is to agree a number of septic tank upgrades to sewerage treatment works at a number of homes around the area of the development site in a sulfinate quantity to offset the proposed development. These upgrades would need to be secured and confirmed through section 106 agreement with the council and various householders.
If a site has sufficient space the is a possibility to provide on site mitigation. however this will require significant space for secondary and tertiary water treatments such as reed beds and percolation beds.
Otherwise a developer can seek to purchase livestock farm and decommission this to create offset for the development.
Three years on and a new government
Despite complete stoppage on housing planning approvals for a large portion of Norfolk there has been very little action to rectify the actual pollution problem (water companies and farmers).
The current Government has a target to build 1.5 million homes over the next 5 years. Considering Nutrient Neutrality is currently holding up approximately 10% of this in the planning moratorium. This combined with the elevated requirements of biodiversity net gain adding complexity to planning applications it is unlikely they will achieve this.