New Lower Thames Crossing – Ground Surveys Commencing
Residents’ Association councillors received the e-mail below from Highways England at the end of last week. If there are further updates we will add them to our website.
‘I am writing to let you know about ground survey work that will begin shortly in your local area. Known as Ground Penetrating Radar surveys (GPR), they will start from Monday 28 October. The work will be carried out in two phases and we expect to finish in mid-December.
These surveys will provide a clearer picture of the locations and types of utilities buried beneath the carriageway along the proposed route of the Lower Thames Crossing. This will help us to improve our designs and to develop our application for the Development Consent Order (DCO).
While the works themselves are not noisy or intrusive, some of the surveys will require traffic management plans. This will ensure the safety both of our contractors and road users.
I have provided more details of the GPR surveys and traffic management plans below. We have also launched a dedicated section of our website about the GPR surveys, including a map and an FAQ section.
GPR survey methods and equipment
GPR uses radar pulses to create a profile of what the ground looks like beneath the surface. The two types of GPR we will use are
- Mobile GPR
- Push GPR
Mobile GPR uses equipment attached to a van or tractor to carry out non-intrusive surveys of roads. We will use Mobile GPR for the majority of our surveys.
Similar in appearance to a lawnmower, Push GPR is used on paths and walkways. An operative pushes along the equipment to collect information.
What to expect
Our priority is to carry out these GPR surveys while minimising their impact on the local community. We continue to work closely with the relevant Local Authorities to obtain the necessary approvals while limiting any disruption that may be caused.
- GPR surveys are non-intrusive and will not cause any noise disruption.
- We will operate flashing lights on our survey vehicles for the safety of our contractors and road users.
- The survey vehicles will be moving continuously at 10mph, minimising the disruption caused.
- At certain times there will be lane closures for safety reasons. Two-way traffic lights or stop/go signs will be in operation.
- Access to properties will be maintained throughout the duration of the works.
Hours of operation and duration
Where possible, the mobile GPR surveys will take place Monday to Friday during daytime off-peak hours, between the AM and PM peaks. In areas that experience high traffic flows throughout the day, the mobile GPR surveys will place overnight on Monday to Friday, between 8pm and 6am.
Subject to favourable weather conditions, the GPR surveys will start from Monday 28 October and finish in mid-December.
Phasing of GPR surveys and traffic management plans – We will carry out the GPR surveys in two phases in locations in Thurrock, Havering and Gravesham.
Phase 1: Monday 28 October – Friday 15 November – In Phase 1 we will use a Mobile GPR van escorted by a traffic management vehicle. Temporary road signage will be used when required.
Phase 2: Monday 11 November – Friday 20 December – In Phase 2 we will use a Mobile GPR van and some Push GPR. Our traffic management will potentially include lane closures and temporary traffic lights.
Locations and type of survey working
Phase 1: Monday 28 October – Friday 15 November
Thurrock and Gravesham – Mobile GPR. Various locations. Maximum one day or one night at each location.
Havering – Mobile GPR – survey van escorted by a traffic management vehicle. Some temporary road signage.
Maximum one day or one night at each location.
- Ockendon Road
- St. Mary’s Lane (B187)
Phase 2: Monday 11 November – Friday 20 December
Thurrock – Mobile GPR. Various locations.
Gravesham – Mobile and Push GPR. Various locations.
M25 Junction 29 roundabout (J/W A127) – Mobile GPR. At Junction 29 we will close first the inner ring and then the outer ring of the roundabout while the GPR van carries out the survey. Maximum one or two nights.
M25, north of Junction 29 (A127) – Mobile GPR on high-speed roads. Approximately five or six traffic management vehicles will be deployed at intervals, diverting traffic across lanes safely, while the GPR van carries out the survey. Night time only.
Please visit our website to find out more information about the GPR surveys, including a map and a FAQ section.‘