vibration criteria for assessment for the impact on DLR assets
Request ID: FOI-0516-2122 Date published: 28 June 2021
You asked
To further clarify the request:
Please provide the vibration criteria for assessment for the impact on DLR assets from vibration due to construction activities on adjacent sites.
Which site or which section of DLR track or embankment is irrelevant. Please provide the requested information and think carefully before refusing to provide the information.
We answered
TfL Ref 0516-2122
Thank you for your request received by Transport for London (TfL) on 11 June 2021 asking for the vibration criteria for assessment for the impact on DLR assets from vibration due to construction activities on adjacent sites.
Your request has been considered in accordance with the requirements of the Freedom of Information Act and our information access policy. You asked:Please provide the vibration criteria for assessment for the impact on DLR assets from vibration due to construction activities on adjacent sites.
Unfortunately we do not hold the information you have requested. We reiterate, due to the nature of DLR assets and control systems and the variety of ground conditions and assets along the DLR network, the DLR do not apply a generic thresholds for vibration, nor do DLR use tables for each asset indicating maximum vibrations that each asset can accommodate.
Please note that the condition of DLR assets adjacent to any development would also be a key factor when considering impact of vibrations from adjacent construction. The location of a proposed development and method of working is essential to know when considering the risks it presents to existing DLR assets and operations.
As per our previous response, please contact our Outside Parties team at [email protected] and include which particular site is of your interest, so we can allocate an engineer to provide more advice specific to your works proposals.
The process our Outside Parties Engineers follow is described below, to give you a better understanding of how we manage external risks to our DLR assets and operations:
When contacted about a proposed development that may impact DLR assets or operations, we will ask the developer to complete a Developers Questionnaire. This document allows the developer to outline their proposal along with the location and type of construction works anticipated, so that we can review the DLR assets in the location and advise on potential impact and anticipated mitigation measures required
Where there will be an impact or risk to DLR assets or operations, we support the developer and our time is recoverable. We would ask the developer to complete an ROCD form and a New Customer Form to record this commitment. These documents set out the agreement to cover DLR engineer time and KAD (the DLR Operator/maintainer) support costs. NOTE: where developer proposals involve altering or creating new DLR assets, the Developer will be required to enter into a Development Agreement.
For all new jobs we undertake a works review and risk assessment to determine what additional measures and agreements may be required, e.g. impact assessments, asset protection agreements, licences, etc. Until we have visibility of Developer proposals, we cannot comment on the potential impact and mitigation measures that are required.
I attach two documents to provide general guidance for developments that could impact DLR assets and operations:
Guidance to Third Party Developers – this is general guidance on the considerations when designing and planning works adjacent/over/under DLR property and assets. NOTE – this document is being updated, however I have attached the current version in use. You may notice that it refers to DLR Engineering Standard ES-101 Noise and Vibration Policy. This policy relates to the vibrations caused by DLR operations, not vibrations that the DLR assets can accommodate from external works.
Advice on the Protection Process – this provides general guidance to the Developer on the process of our reviews and outline timescales for access and responses.
Please note that in accordance with TfL’s obligations under Data Protection legislation some personal data has been removed, as required by section 40(2) of the FOI Act. This is because disclosure of this personal data would be a breach of the legislation, specifically the first principle which requires all processing of personal data to be fair and lawful. It would not be fair to disclose this personal information when the individuals have no expectation it would be disclosed and TfL has not satisfied one of the conditions which would make the processing ‘fair’.
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
Sara Thomas FOI Case Management Team General Counsel Transport for London
