Biodiversity net gain of 20% to be encouraged on new developments in Cambridge and South Cambridgeshire
New housing developments in Greater Cambridge will in future be required to provide as many bird boxes as there are homes being built.
Paving of gardens will be discouraged, fencing must be hedgehog friendly and one in four new homes on development sites should feature a bat box.
These are among the raft of measures contained in a supplementary planning document designed to drive improvements in biodiversity in Cambridge and South Cambridgeshire.
Councillors will be asked to approve amendments to the document on Tuesday (January 11) after 40 responses to a public consultation held from July to September 2021.
Once adopted, the guidance will be used by councillors to determine planning applications.
It encourages all new developments to achieve a 20 per cent net gain in biodiversity, measured using Defra’s Biodiversity Metric 3.0 or its successor.
The document states: “Although a mandatory requirement for 10 per cent net gain in biodiversity value is mandated by the Environment Act 2021, a value of 20 per cent is likely to be encouraged as best practice in order to meet the Natural Cambridgeshire target of doubling the amount of land managed for nature from eight per cent to 16 per cent of the county’s area.”
Homeowners and developers are told they will “often require an ecologist to undertake ecological surveys and mitigation work”, with biodiversity baseline information required.
The document stresses: “Developers will be expected to avoid direct and indirect impacts on irreplaceable habitats.”
The council says they will “refuse applications that would result in the loss, deterioration or fragmentation of irreplaceable habitats unless the need for, and benefits of the development clearly outweigh the loss, and a suitable compensation strategy exists”.
The guidance advises that applicants “must ensure that planning applications are supported by adequate ecological information, using up to date desk studies and site assessment” - and that includes householders and developers of small sites.
The document notes that Greater Cambridge is home to European protected species including great crested newts, otters and 12 species of bats - including the population of Barbastelle bats at Eversden and Wimpole Woods Special Area of Conservation - and there are a few dormouse records.
Legislation also protects species found in Cambridgeshire such as white-clawed crayfish, water vole, badger, common lizard, grass snake and barn owl, while the area also supports populations of fairy shrimp, including at the Whittlesford/Thriplow Hummocky Fields Site of Special Scientific Interest.
And there are more than 200 UK Priority Species in Cambridgeshire - listed by the Cambridgeshire and Peterborough Biodiversity Group - including recognisable but declining species such as common toad, brown hare, house sparrow and hedgehog alongside a range of lesser-known invertebrates, and plants such as purple milk-vetch. Developments that will cause significant harm to such species, without adequate mitigation, face refusal.
Meanwhile, the Cambridgeshire Habitat Opportunity Map identifies priority habitats that the councils are also keen to protect.
Bird boxes for new developments are required to aid building-dependent species such as breeding swifts, house sparrows, starlings and house martins.
The document also:
- Discourages artificial lighting, particularly in areas of natural habitat, as it can impact nocturnal species;
- Encourages biodiverse roofs and walls, particularly where the opportunities for ecological enhancement on a site area are limited;
- Urges developers to check locations of known toad crossings; and
- Favours sustainable drainage systems to managing rainfall from hard surfaces.