County Durham LPA BNG

County Durham runs from the North Pennines National Landscape in the west, through Teesdale and Weardale, to the magnesian limestone plateau and coast in the east. Upper Teesdale holds blanket bog at High Cotherstone Moor and Cow Green Reservoir, and Hannah’s Meadow in Baldersdale is a surviving upland hay meadow. Thrislington National Nature Reserve has the most extensive stand of unimproved magnesian limestone grassland in Britain, and Castle Eden Dene is an ancient wooded valley running to the coast. The council counts 88 SSSIs, 6 Special Areas of Conservation, 3 Special Protection Areas, 2 Ramsar sites, 308 Local Wildlife Sites and 50 Local Nature Reserves, but woodland covers only about 9% of the county, against about 14% for the UK.

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Biodiversity Net Gain became a legal requirement for major developments in England on 12 February 2024, and for small sites on 2 April 2024. The County Durham Plan was adopted on 21 October 2020 and Policy 41 covers biodiversity net gain. The council adopted its Biodiversity Supplementary Planning Document on 4 April 2025. It encourages applicants to exceed 10% but sets no higher threshold, requires on-site delivery before off-site, and allows national statutory credits only as a last resort when there is no local market. The County Durham Local Nature Recovery Strategy was approved by Cabinet on 18 March 2026 and applies a 15% uplift to units for habitat measures in its mapped areas.

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The council is not currently accepting registrations of interest for new off-site BNG sites and directs applicants to agreements with designated responsible bodies; sites must otherwise be secured for 30 years by a section 106 agreement or conservation covenant. Nutrient neutrality adds a second test. Part of the county lies in the River Tees catchment of the Teesmouth and Cleveland Coast SPA and Ramsar site, where Natural England’s March 2022 advice applies with no size threshold, so even a single house may need screening. Small eastern parts of the River Eden SAC catchment also fall within the county.