4.2 Biodiversity and green spaces

Figure 15 Biodiversity and green space in Greater Cambridge today

Biodiversity means the richness of the living environment around us. A healthy and biodiverse environment is important to ensure Greater Cambridge's future prosperity and the wellbeing of all who live, work and study here.

Biodiversity is supported by green infrastructure - a term for the network of natural and semi-natural spaces across the area. This network includes parks and recreation grounds as well as more wild spaces like woodland, scrubland and grassland areas, rivers and other water bodies.

Greater Cambridge on the face of it seems very green. The River Cam is a designated County Wildlife Site in recognition of the river's importance in linking semi-natural habitats, including ecologically designated sites in Cambridge such as Stourbridge Common, Sheep's Green, and Coe Fen Local Nature Reserves. In South Cambridgeshire, there is a network of wildlife habitats, including ancient woodlands, orchards, rivers and wildlife corridors. These include sites like Eversden and Wimpole Woods, of international importance.

However, in recent decades biodiversity in the area has been decreasing. The rural area is dominated by agricultural land, which is often not biodiverse, and in urban areas the loss of gardens and increase in urban uses reduces biodiversity. Chalk streams which feed the River Cam, and get their water from the aquifer that provides much of our drinking water, have run very low in recent years, impacting on the wildlife that lives there.

Both Councils have recognised the pressure on the natural environment and want to explore how the next Local Plan can do more to improve the green infrastructure network. This will form a key part of the overall development strategy for the area and will be an important part of the wider response to climate change.

4.2.1 What do we have to do?

National planning policy requires us to protect and enhance valued wildlife habitats and sites of biodiversity importance. Whilst we have previously been required to protect and enhance biodiversity through development, national policy now requires development to achieve a net gain for biodiversity. Biodiversity net gain requires developers to ensure habitats for wildlife are enhanced and left in a measurably better state than they were in before development.

Local Plans also need to take a strategic approach to promoting the restoration and enhancement of the green infrastructure network, taking into account its varied benefits including supporting biodiversity, providing opportunities for recreation, mitigating and adapting to climate change and enhancing landscape character. This means having a clear understanding of what is present in the area and exploring how planning can help protect and improve it.

4.2.2 What are we already doing?

Our adopted 2018 Local Plans seek to protect and enhance biodiversity and open space, but the next Local Plan provides an opportunity to explore how we can do more.

Cambridge City Council and South Cambridgeshire District Council have declared biodiversity emergencies^[28]. As members of the Natural Cambridgeshire Local Nature Partnership^[29], the Councils support the Partnership's vision to double the area of rich wildlife habitats and natural greenspace within Cambridgeshire and Peterborough^[30].

The Partnership has prepared a Developing with Nature Toolkit^[31] to help developers and infrastructure providers to demonstrate their commitment to achieving a net biodiversity gain to the public, local authorities or shareholders.

We are also working as part of the Oxford-Cambridge Arc exploring investment across this wider area in the natural environment.

We are commissioning an evidence base study to inform how the new Local Plan can help achieve an enhanced and expanded Green Infrastructure network. This will consider how and where development is planned, and how it can help deliver new or improved wildlife areas and green spaces.

4.2.3 What are the key issues?

Improving the green space network

We need to consider how attractive, accessible and well-designed open space is created and protected. Key issues include:

• How we can improve, add to and connect up our green spaces.
• How our green spaces can create wellbeing through places to relax and socialise, and healthy lifestyles through places for play and sport.
• Balancing public access to nature, which is known to have health and well-being benefits, with the need for some natural habitats to be undisturbed and wild.
• Making green spaces multi-functional – absorbing and storing stormwater, improving biodiversity, and absorbing carbon emissions.
• How rural biodiversity is balanced with other demands on the countryside, such as agriculture.
• How new development can directly deliver or contribute to the enhancement of green and natural spaces.

We would also like your views on sites that could be suitable for new green infrastructure. If you have ideas, please respond to question 3.

Achieving biodiversity net gains on future developments

For individual developments the Local Plan will need to require biodiversity net gains. We will need to consider how we guide developers to achieve this. For example:

• How the design of buildings themselves can support biodiversity through the materials and features they include, such as green roofs.
• How landscape design can encourage biodiversity while meeting other functional requirements and being easy to maintain in the future.
• How development supports wildlife in the face of climate change, through creating resilient new habitats.
• How developments are phased and monitored to ensure that biodiversity net gain is achieved in practice and not just in theory.

Tree cover

Tree planting makes places more attractive and helps to mitigate the rate of climate change through absorbing CO₂ and decreasing the urban heat island effect. Cambridgeshire has a very low proportion of woodland, compared to the rest of England. The new Local Plan will need to consider how we can increase tree cover as part of new developments, and support the implementation of the Cambridge Tree Strategy^[32].

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