FOI release

A20 Sidcup Bypass (Drainage, Flooding, and Agency Liaison)

This request was refused in part, so we didn't provide some of the information the requester asked for. This may include information where we can neither confirm nor deny that we hold it.

Case reference EIR2025/01537

Received 5 August 2025

Published 18 December 2025

Request

Please provide the following information in relation to the A20 Sidcup Bypass, specifically the stretch between Crittall’s Corner and McDonald’s, for the period from 1 January 2019 to the present:

1. Whether National Highways has been consulted, informed, or involved in any capacity (technical, advisory, or operational) concerning:

• Gully performance, drainage failures, or water-shedding issues on or affecting this stretch of road

• Surface water flooding, aquaplaning risk, or standing water problems reported in this area

• Any safety, engineering, or flooding-related discussions with Transport for London or the Metropolitan Police

2. Copies of any correspondence, reports, site reviews, or recommendations produced by or sent to National Highways that refer to:

• The condition or design of gullies or drainage infrastructure affecting the A20 in this location

• Engineering assessments or advice on flooding mitigation, especially in response to repeated collisions or weather-related incidents

3. If National Highways has not been involved in this location, please confirm whether:

• The A20 in this area lies entirely outside your operational remit

• You hold any historic drainage-related alerts, mapping data, or water run-off records that overlap or affect this corridor

Response

I have established that the information you have requested is not held by National Highways. It therefore falls under Regulation 12(4)(a) of the Environmental Information Regulations 2004.

Information provided

3. If National Highways has not been involved in this location, please

confirm whether: The A20 in this area lies entirely outside your operational remit

National Highways is the highway authority for the A20 between the M25 and the Kent/London boundary. This is close to the junction of the A20 with B2173 Maidstone Road, approximately 350m east of the McDonalds. To the west of this location, Transport for London (TfL) is the highway authority for the A20 including the location you have referred to.

Advice and Assistance

Our predecessor organization, the Highways Agency, was responsible for this section of the A20 prior to the creation of TfL in 2000. Any historic operational records from that period would now be past their retention period and would have been destroyed.

We engage regularly with TfL to co-ordinate our activities across the boundary between our networks. For example when either authority needs to close lanes to undertake works close to the boundary, but such discussions would not involve the exchange of technical information relating to drainage assets or drainage performance.

If you have not done so already you may wish to submit a request to TfL. Details of how to do this can be found on their website.

Documents

There are no documents for this release.

This is National Highways' response to a freedom of information (FOI) or environmental information regulations (EIR) request.

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