TfL Ref: 0382-1920

Thank you for your email received by us on 1 May 2019 asking for information about the trees on London Underground’s Central Line embankment.

Your request has been considered in accordance with the requirements of the Environmental Information Regulations and our information access policy.  I can confirm that we hold the information you require. You asked:

Can you please explain how chopping down all the trees on the Central Line embankment stabilises the ground

And the impact on air quality and plans to mitigate the negative impact

I can advise that the Earth Structures team is undertaking a programme of stabilisation works to existing earth structures. As part of this programme, the cutting known as C056 CTSB located between Chigwell and Grange Hill Stations on the Central line has been identified as having a high risk of landslip failure that could affect the safe running of the Central line. The scope of the project is to assess the risk, put forward a design solution and implement.

To start construction works the area needed to be cleared of all vegetation; we have been liaising with the Tree Officer who has identified that there are no protected trees on the cutting and have conducted an ecological report that identified no protected species.

The proposed permanent works involve remedial measures consisting of soil nailing, bored piles, H-piles and regrading. Once all works are complete the intention is to replant the area with seeded grass and a number of sapling trees.

Poor air quality in London generally is caused by nitrous oxides and particulate matter mainly from diesel combustion. The removal of vegetation on the embankment will have no negative impact on the air quality in this area.

If you require any additional information please email the Chigwell Project Team via: [email protected]

If this is not the information you are looking for, or if you are unable to access it for any reason, please do not hesitate to contact me.

Please see the attached information sheet for details of your right to appeal as well as information on copyright and what to do if you would like to re-use any of the information we have disclosed.

Yours sincerely

Jasmine Howard
FOI Case Officer
Information Governance
Transport For London