Getting to the root
of the issue

About 160km of the track for which we are responsible is above ground and home to flora and fauna including bats, badgers, snakes, birds, insects, plants and many different trees and flowers.

“We need to ensure that there is a balance between the needs of the railway and those of the vegetation and wildlife,” explains Steve Judd, Tube Lines Environmental Asset Manager. “My team is aware of the different types of wildlife and vegetation on our land and we do all we can to protect them.”

Information is the key to good wildlife and vegetation management and in 2006 we carried out wildlife surveys at depots and sidings across the Jubilee, Northern and Piccadilly lines. The findings have been loaded onto our computerised geographical information system (GIS), which maps the environment around our infrastructure, including tree species and wildlife areas as well as noise and contaminated land hotspots across all our sites. We update this regularly to include sightings of protected species and invasive plants and other environmental information such as complaints and discharge points. We also post up signs on sites where we find protected species including slow worms, nesting birds and roosting bats.

GIS is available to every employee through our intranet and is proving very helpful for project planning. “It is important to address environmental issues as early as possible and GIS helps project managers to do this,” comments Steve.

Wildlife management strategy

In 2007 we used our databanks to develop a wildlife management strategy which provides project managers and employees with practical guidance and instructions, from specialist advice to gaining the necessary licences to work.

“One of the key elements of the wildlife management strategy was to make it accessible and easy to understand,” explains Rebecca Brown, Environment Adviser. It is divided into three sections:

• Species guidance to help employees identify and deal with protected and important species and habitats likely to be found on our land
  
• Activity guidance to provide information on how best to manage activities such as grass cutting, tree management and working in tunnels
  
• Action plans identifying improvement actions to protect and enhance wildlife and the environment further

“This working document will be updated regularly and is due to be launched to coincide with the opening of our second nature area in May 2008,” Rebecca adds. “The first is our thriving bat roost on the Northern line.”

Second green roof

We installed a second green roof in 2007, on our new three-storey train crew accommodation building at Stratford. Our first, at the Northern line control centre, was the largest of its type in London when installed in 2006.

Green roofs are excellent for adapting to climate change as they soak up rainwater, delaying its return to the drainage system and reducing the risk of flooding as well as providing more green space to local wildlife. They are also excellent insulators, saving approximately 0.5 tonnes of CO₂ per m² per year. Sustainability is fundamental to the Stratford building’s design.

Pest control

There are times when wildlife or vegetation can present a risk to the railway or to people. A swift response from Steve Judd’s team brought an outbreak of oak processionary moths under control before they did any damage in 2007.

The moths were found on two embankments in the Park Royal area at the west end of the Piccadilly line. At the caterpillar stage these unpleasant and non-native moths can cause a skin rash if they are touched.

“As soon as we heard about the moth outbreak in the borough we tested all our sites and found about 90 groups of them spread across about 40 different trees,” explains Steve. “We treated them all within a week as it was essential to act quickly to prevent them from turning into moths and laying eggs which would cause future problems. No more moths have been found since. We will continue to monitor this in 2008 to ensure that they have all been eradicated.”

Keeping unwanted invaders at bay

Although we strive to protect most plants, some weeds can be very damaging to the network. In 2007 we reviewed and revised our approach to managing Japanese knotweed – an invasive plant capable of growing through concrete – with the successful trial of a new single-application weedkiller. “We achieved 80 per cent control with just one application,” says Steve Judd. “Using traditional methods it could take 7-10 years to achieve this level of control, spraying three to five times per year. Following this successful trial we will be using this new product across the network to control Japanese knotweed from 2008. We hope to eradicate it from all 122 sites where it has been discovered within the next two to three years.”

This product will help us to reduce the amount of waste we send to landfill, too. “Until now we have been obliged to excavate areas infested with Japanese knotweed, put the soil into special skips and send it to landfill,” explains Steve. “The new method allows us to treat on site.”

Another innovation in weedkilling is a new concentrated spray gun which produced very good results on the Jubilee line in 2007, reducing the volume of liquid and herbicide needed to prevent the spread of unwanted vegetation and cutting the weight of equipment that contractors have to carry. It also reaches about seven times as far as older models, making it far more efficient. This will be introduced to the Northern and Piccadilly lines in 2008.

• Environmental impacts
• Noise
• Waste and materials
• Pollution
• Wildlife
• Energy and utilities
• Climate change