Olympic Park landscaping begins with planting 6,000 trees

Here in the built environment community, if we talk about the Olympics we tend to think of the sweeping flourishes of Zaha Hadid’s aquatics centre or the rather grand presence of the stadium. So it’s easy to forget that these fabulous buildings are set in a park.

But when the Olympic Delivery Authority invited Building to join a tour of the 2.5km2 Olympic Park site yesterday to mark the planting of the first of 6,173 trees, it became clear that the landscaping involves the same level of design, planning, technology and cutting-edge sustainable techniques that we’re seeing elsewhere on the 2012 project.

For instance, we learned that while 90% of the manmade materials found at the site have been recycled, living materials are also being recycled: thousands of seeds and cuttings of over 30 species from the site’s wetland areas were taken from the site before the diggers went in, in 2008.

There then followed a complex and fiddly operation. The samples were whisked off to the Salix nursery on the Gower peninsular in Wales, where they were grown carefully before being transported again to waterbeds in Thetford, Norfolk. Here, the crop – now numbering over 300,000 plants, including reeds, rushes, grasses, sedges, wet wildflowers and irises – was planted in coir mats. Now these mats are being transplanted to the Olympic Park riverbanks, and yesterday some grasses were already in place and looked to be flourishing.

For those of us usually focused on the built environment, the Olympic Park is proof that the living environment can be just as interesting, beautiful – and technical.

This project is an important step in the conservation of wetland areas, which are under threat. John Hopkins, project sponsor for parklands and public realm, told us that the park’s wet woodland area, which will cover 0.4ha, will be the largest of its kind in the country.

There will also be meadows of colour co-ordinated wild flowers, which will be strategically planted late to ensure they’re flowering when the Games are on in August, by which time blooms have usually faded. There will be the 2012 Gardens and the Great British Garden, which will show off native plants and Britain’s history of plant collecting around the world respectively.

All this will be set among gently sculpted hills. Although yesterday only a few of them bore newly planted (though 20-year-old) trees and even fewer had grass, they already frame views of Olympic venues. Eventually these mounds will mean, Hopkins assures us, that “in some places in the park you won’t even be able see any buildings”.

Behind the prettiness the park will also serve the businesslike function of flood risk management. It is designed to flood and this includes withstanding severe, “once in 100 years floods”, Hopkins says. The park should absorb enough floodwater to protect around 5,000 properties surrounding it - which is much more than the Olympic venues and adjacent athletes’ village. It also has a fish refuge, which aims to protect fish and their eggs from being swept away.

The trees being planted now, which were grown by Hilliers Nurseries in Hampshire, will play a big part in flood defence, particularly willow, poplar and alder, which will be planted in river areas. Hilliers is also supplying ash, birch, hazel, cherry, London plane and lime.

For those of us usually focused on the built environment, the Olympic Park is proof that the living environment can be just as interesting, beautiful – and technical.

To see the latest webcam images from the wet woodland, click here, and for woodland bowl, click here.