BOB HALL: highgate Station's green roof is an ecological triumph
PUBLISHED: 15:54 05 September 2007 | UPDATED: 14:37 07 September 2010
Since taking over responsibility for Hampstead Heath in 1989, the City of London has taken very seriously the need to protect the Heath boundary from surrounding development. Delicate negotiations and lobbying have taken place with respect to many propose
Since taking over responsibility for Hampstead Heath in 1989, the City of London has taken very seriously the need to protect the Heath boundary from surrounding development.
Delicate negotiations and lobbying have taken place with respect to many proposed projects to ensure that so far as possible the views from the Heath are not compromised - most recently Athlone House.
This was an example of how the Heath and its neighbouring community can benefit from detailed discussions with developers.
The parcel of land which was agreed to be handed over as a result of such talks not only acts as a buffer zone but also provides an important wildlife sanctuary and is a very welcome extension to the Heath.
While the City may not be legally obligated to apply this protection of boundaries to its open spaces, it nevertheless takes a common-sense approach to ensuring they are, so far as practicable, protected.
A good example is Tubelines' proposal to build a control centre for the Northern Line adjacent to Highgate Wood. For a number of reasons, this was a similarly sensitive project. There were fears that the building as it was initially designed would create an eyesore right on the boundary of the Wood, which is a surviving remnant of the ancient forest of Middlesex and was designated a Site of Metropolitan Importance for Nature Conservation in 1990.
Tireless lobbying by members of the local conservation groups, my predecessor Catherine McGuinness, the City of London's Ray Poole and MP Lynne Featherstone, alongside councillors from Haringey, proved fruitful and Tubelines agreed to adapt its structural plans to include a green roof on the building.
Staff at the Wood also worked closely with Tubelines to advise on considerate construction to avoid disturbing bat roosts in the nearby area.
Recently, members of the Highgate Wood Consultative Committee were able to visit the building, which is nearing completion, and the results were impressive. The sedum is already well-established and it is popular with bees and other insects.
Not only is there the obvious important aesthetic improvements of green roofs, but their contribution to the surrounding environment is invaluable. They help reduce water run-off during storms by absorbing a large percentage of the rainfall, which is particularly relevant with the weather of the last few months.
They also help insulate buildings to reduce heat loss from the roof in winter and the heat build-up during the summer, leading to a reduction in energy use and costs.
Additionally, the plants act as air filters, removing carbon dioxide and absorbing pollutants in the air to create a cleaner environment.
In an area of such ecological importance as Highgate Wood, this contribution to improving the surrounding area to protect the existing flora and fauna for the future is invaluable.
Tubelines has acknowledged that there had been some reluctance initially to the green roof proposals - partly as a result of design and cost implications - but that they are so gratified by the outcome that they are considering installing them on other buildings in the future.
This was particularly pleasing to hear and the fact that it has been such a success will, hopefully, encourage others to adopt similar projects in the future.
Visitors can learn more about Highgate Wood by taking part in a free summer guided walk led by the keepers this Saturday (August 25).
The Wood dates back to pre-historic times and has a diverse ecology - up to 70 species of bird have been recorded there, many of which regularly breed in its 50 species of trees and shrubs, the most common being oak, hornbeam and holly.
More than 978 species of invertebrate and a wide variety of fungi have been spotted in the dead-wood which is now left to protect the wildlife which also includes foxes, grey squirrels, five species of bat, 180 species of moth, 12 species of butterfly and 80 species of spider.
Small conservation areas of up to one acre in size are also established every five years to help protect the delicate undergrowth, which can easily be damaged as a result of the Wood's popularity with visitors and the denser canopy of mature trees which now exist.
These small zones are fenced off from public access for 10 years, helped along with planting of wild flowers and bulbs, to allow the woodland to regenerate and ensure its existence for many years to come.
q Bob Hall is Chairman, Hampstead Heath Management Committee, City of London