Introduction to …

We are looking at the land needed for construction and access routes and how we might phase the construction work. This will help us plan measures to reduce potential impacts.

We will use construction techniques that minimise disruption. This includes the bored tunnel method, which will minimise impacts on the riverside marshes and riverbed, and offsite construction, which enables faster progress and use of the river for transporting materials.

What's happening on the project

Learn more about the latest developments on the project.

Building the crossing

Before the main construction work can begin, we need to acquire land and prepare the site. This includes:

  • diverting public rights of way and utilities
  • creating new habitats
  • carrying out flood avoidance measures
  • species relocation
  • removing vegetation as necessary
  • making any contaminated land safe
  • completing detailed surveys about the land and surrounding area
  • archaeology
We will build the new roads and tunnel in phases, which will be the most efficient way of working so that different elements of the project can be completed at the same time. (See timeline)
We will carry out most of the work between 8am and 6pm on weekdays (excluding bank holidays), and between 8am and 4pm on Saturdays. These are standard hours for construction projects up and down the country, although crews may work for up to an hour before and after to prepare and close the site. From time to time we may also have to do some maintenance work on Sundays. We will work closely with highways teams from the local authorities in each affected area to identify the best working times for each site, so these times may vary.

As with any project of this scale, we will have to do some of the work at night. For example, where possible we will work on existing roads overnight to reduce disruption to drivers going about their daily journeys. Tunnel construction will be a 24-hour operation throughout.

It is likely to take around six years to build the tunnel. During this time, we plan to have a construction site next to the northern entrance. This will include equipment for producing the precast concrete for the tunnel lining, a water treatment system and a temporary substation to provide power for the tunnelling machines.

Tunnelling work could begin from either the northern or southern entrance. Based on the information we currently have, we expect to begin near the northern entrance. Two machines will excavate the tunnel, which will then be lined with precast concrete segments.

On average, a tunnel boring machine excavates at a rate of between 50 and 125 metres a week, depending on the model.

This project is an enormous undertaking using the most sophisticated tunnelling equipment in the world. It will mean underground construction and activity will take place 24 hours a day, seven days a week to complete the tunnel as soon as possible. It is standard practice during 24- hour operations to put in place special measures such as noise barriers to keep potential impacts to a minimum.

During construction, we will make sure we keep residents, businesses and road users informed of planned works in advance and share information on progress.

We will build the new roads, junctions, bridges and underpasses at the same time as the tunnelling work. Most of this will be done during standard hours as we discussed earlier in this chapter.

The new road will connect the M2/A2 in Kent with the M25 south of junction 29 in Essex, crossing the A13 north of Chadwell St Mary. To connect with these existing roads, as well as the A1089, we will construct new junctions and will have to carry out some work on these roads as well. This includes improvements such as road widening for the M2/A2 and M25.

Most construction materials will be transported to the sites by road, which will have some impact on the road network and road users. At locations where new connections to the network will be created, we will carry out traffic management to segregate the construction sites from road vehicles.

Some local routes will be affected by construction, with some roads temporarily closed and others having temporary diversions, traffic lights and/or lane restrictions. We will provide advance warning so people can look at alternative routes or travel arrangements.

The predicted impacts on specific roads are classified as follows:

  • High: road may close, with possible diversion and/or lane restrictions
  • Medium: road remains open, with temporary diversion, traffic lights and/or lane restrictions
  • Low: road remains open, with temporary diversion, traffic lights and/ or lane restrictions

Building the new route will affect the local environment. Wherever possible, we are determined to protect, and look for opportunities to enhance, the local environment and improve biodiversity.

We are already carrying out extensive surveys, monitoring and investigations, which are helping us to understand how the crossing might affect air quality, noise and the landscape. This information is helping us to find ways to reduce these impacts. Once all that information has been fully assessed, we will publish the findings in our Environmental Statement, as part of our DCO application.

We will produce a draft Code of Construction Practice (CoCP), which we will submit with our DCO application. It will describe how we will reduce the disruption to local communities and the environment during construction and our approach to limiting noise and vibration.

As we develop the CoCP we will work closely with specialists in the local authorities to make sure that it best reflects the needs of their local communities

We will excavate a significant amount of material, which will be processed and reused onsite where possible. Material that cannot be reused, such as hazardous waste and contaminated soil, will be safely disposed of in line with regulations. If practical, we will transport some material that cannot be reused by river rather than by road. We are currently looking at how this might be possible. If we use the river, we may need to build a new temporary jetty or use an existing one.

To reduce construction traffic using the roads, we are considering alternatives, such as river transport, to move materials and waste to and from work sites

As with any road project, we will make sure we protect species and habitats in the area. These include great crested newt breeding ponds, reptile hibernation areas and bat breeding roosts. We will only remove vegetation during the bird breeding seasons (typically early March to late August) if absolutely necessary, and this will be overseen by an appropriately qualified ecologist.

Each construction site will have temporary buildings and storage areas, and will include offices, space for equipment and materials, parking and staff facilities. Some sites will include specialist zones, such as the tunnel construction area at the north entrance site.