landscape strategy
Public Realm Typology Mix
Within the developed areas of the site the public realm is abundantly green and provides visual and physical amenity to residents. Slip parks, community growing slopes, backyard allotments, parking courts, bus stops, playgrounds and wild learning spaces are all proposed on site. The diagram below shows the matrix of typologies.
Swimming Pond
Woodland Play
Slip Park
Viewing Gallery
Back Garden
Growing Slope
Backyard Allotments
Parking Court
Community Gardens
One of the benefits of building on slopes is that they lend themselves to terraced growing space.Allotments and growing space occur within the scheme, within and without streets and behind some of the larger buildings in the hillside village and in the urban village. The growing space will include orchard tree planting, raised beds, potting sheds/green houses; access will be managed by the site management organisation and tool-shares will be available.
Chalk Grassland is a nationally significant grassland habitat; in the UK over 80% has been lost since World War II. The Gomm Valley (as part of the Chilterns and lying on Chalk Geology) can and should play host to a significant amount of chalk grassland. Arable farming is the current prevalent land use on site, this monoculture is poor for biodiversity and could easily be replaced with chalk grassland; indeed in fallow fields chalk grassland species are regenerating at the field margins. The target is to achieve 20 hectares of species rich grassland of which at least 30% will be Chalk Grassland. This will be achieved not just through the development of areas of chalk grassland in the ‘undeveloped’ parts of the site but also through fingers of chalk grassland in the villages.
Little Haldens Park
To the north of the Urban Village is Little Haldens Park. This is a low fidelity parkland landscape which provides an area for picnicking, children’s play and informal recreation. The park will be managed as a field with a margin of longer chalk grassland providing ecological continuity,the centre of the park will be mown to amenity grassland height to allow access for sport and recreation. Through the centre of the park runs the valley route, a 1.8-2.5m wide route .Adjacent to the park are a number of community buildings including a plant centre, Culture Shed, Art + Nature Building
Urban Ecology
In addition to the various grassland habitats proposed on site, woodland belts, blocks and hedgerows of native and naturalised species are also proposed. Together these woodland and grassland networks will allow vertebrates and invertebrates to navigate across the site – better connecting Gomm’s Wood with the AONB to the east. Ecology is not exclusively the preserve of the parkland; urban ecology is as valuable, particularly to residents. Greenroofs (built using site won chalk sub-soil), street tree planting, swales, gardens cumulatively improve biodiversity quality of life
Local Wildlife
The Local Wildlife Site is currently in poor condition – it is designated for it’s a Chalk Grassland– a vegetation type that is in decline and which is also protected (via national regulation) in the adjacent SSSI. The LWS has become scrub and woodland edge habitat which is of lower value than the designation would suggest. The proposal reconfigures the local wildlife site to enlarge it by over 40%. The SSSI and LWS will be put into the same management regime with the intention of regenerating both the SSS Iand the LWS to chalk grassland – providing a critical mass of protected chalk grassland to which access will be managed in order to protect habitats.
Gomm Valley is at present a dry valley. The introduction of hard surfaces and buildings within the ‘developed’ areas of the site results in a need to manage run-off and ensure that ‘discharge’into the municipal drainage networks is effectively at ‘green field’ rates. An added challenge at the Gomm Valley is that the chalk geology discourages the sue of infiltration at the top of slopes due to the potential for ‘solution features’ (sink holes) to form. Instead of using infiltration local to the homes the water will be taken to the base of the valley via a series of swales which will clean the water and provide increased biodiversity. Once at the base of the valley a number of ‘dry ponds’ collect the water in a storm event and slow down the runoff rates. At the southern end of the valley near the Urban Village a wild swimming and a fishpond are located – these will hold water year-round and provide a valuable resource for the new community.