Nutrient Mitigation

There is evidence of high levels nitrogen and phosphorus in the Solent water environment – including evidence of eutrophication at some internationally designated sites. To meet requirements set out in the Habitats Regulations, new housing development across South Hampshire must not add to existing nutrient burdens.

In light of advice from Natural England, our aim is to develop a PfSH-wide strategic approach to mitigation in order to achieve nutrient neutral development – and deliver the planned housing development compliant with the Habitats Regulations.

PfSH successfully bid for a £2m loan by the Solent Local Enterprise Partnership (LEP) from the Government’s Getting Building Fund to be used to secure off site mitigation land in order to assist in unlocking the delivery of housing which has been on hold due to the nutrient neutrality issue. The Solent LEP has advised that the Hampshire and Isle of Wight Wildlife Trust is its preferred strategic partner to oversee a land use change mitigation scheme funded with the proceeds of PfSH’s bid. The Solent LEP is now releasing funds for the scheme following consideration by the Solent LEP Board on 11 December 2020.

The Environment Agency (EA) has confirmed that a review of waste water treatment works nitrate (N) permits will take place.

Southern Water continues voluntary monitoring of nitrate levels in waste water treatment works operating with no Environment Agency nitrate N permit. Initial results of the monitoring are expected in the spring of 2021 and the PfSH Water Quality Working Group as begun discussions with stakeholders around agreeing a methodology to interpret the data once issued.

A full summary of the latest situation can be found in the PfSH report to Joint Committee 22 March here.


Nutrient Calculator

Natural England has published its latest guidance on achieving nutrient neutral housing together with a ‘nutrient calculator’ to help developers deliver homes that do not discharge excess nitrates into the Solent’s protected natural habitats.

Access the calculator, advice and guidance here.