Nitrogen Reduction Mitigation in Poole Harbour Catchment 

Information for developers, landowners and managers about how Dorset Council will secure Nitrogen Neutrality for planned development. Find out why it is important and how we will work in partnership to deliver it. 

Increasing nitrogen levels from sewage and agriculture are contributing to the growth of algal mats in the Harbour. They restrict the growth, distribution, and variety of important food available for wading birds in the Poole Harbour, designated a Special Protection Area (SPA) under the EU Birds Directive to protect rare, vulnerable and migratory birds. 

The majority of nitrogen is generated from agriculture, but a proportion is generated from human sewage. To conform to the requirements of the The Habitats Regulations and The Water Environment (Water Framework Directive) (England and Wales) Regulations 2017 (legislation.gov.uk), we must ensure all new development avoids causing further harm or mitigate the impact in-perpetuity to ensure there is no adverse effect, effectively making development nitrogen neutral.  

National Planning Policy Framework  and Planning practice guidance  outline the procedure that should be followed in deciding whether to approve a proposal. 

Mitigation delivery

We have agreed a mitigation strategy through the Nitrogen Reduction in Poole Harbour Supplementary Planning Document.pdf (1 April 2017)

Developers will be encouraged to design development to secure nitrogen neutrality on site.  

There are three approaches to reducing nutrients entering Poole Harbour Catchment in the strategy: 

1. Land management change to reduce the inputs which may enter groundwater, streams and rivers within the catchment. 
2. Creation of bespoke wetlands to remove nutrients from watercourses.  
3. Landscape scale projects to achieve multiple objectives in addition to nitrogen mitigation such as river restoration/rehabilitation and flood alleviation. 

How we plan to do this

We purchase land or grant fund environmental charities to acquire land to achieve land-use change and where appropriate, wetland creation.  We also welcome opportunities to work with farmers and landowners to secure permanent land-use change to wetlands or woodlands and will continue to work with our partners developing the Poole Harbour Nutrient Management Scheme.  

The governance  

The allocation of CIL funding for nitrate mitigation is overseen by a steering group made up of representatives from Dorset Council, Environment Agency and Natural England.  Final sign-off lies with Senior Officers depending on the level of funding commitment.  All mitigation needs to be secured in-perpetuity to mitigate for the life of the development and this is secured by using standard management agreements.  

How you can apply

If you would like an informal conversation about your land or you would like to propose a potential project, please contact the Nitrate Mitigation and Compensation Project Officer: