Nutrient Neutrality

Once designated the local planning authority (LPA) needs to discharge its duty under the habitats directive by only approving development where it doesn’t increase the nutrient load within the area designated which is usually a water catchment area.

NE designates areas where the catchment into which the nutrients from a development discharge contains sites that are designated with one or more of the following designations a Special Protection Area (SPA), Special Area of Conservation (SAC) or a RAMSAR site (a site designated by the Ramsar convention) and those sites are in unfavourable condition as defined by NE. With the reason for their unfavourable condition being due to an excess of phosphate or nitrate.

The nutrient load of a development can be reduced by on site measures such as swales and reed beds or by reducing the nutrient produced from other land within the same catchment. Within a catchment land management can be changed to reduce the nutrient load from that land. Examples of this are stopping agricultural production, reducing the nitrogen and phosphate inputs, planting trees and establishing buffer strips.

How long the solution needs to be in place varies depending on the situation in the particular catchment. As the local water company maybe upgrading its sewage treatment works and this may remove the need for a solution to a particular development once it takes place. However, in the absence of this NE are likely to require the solution to be in place for 80 to 120 years.