Highways England has today launched a consultation on one of the most strategically important stretches of road in the UK. In developing the options for the Lower Thames Crossing the Government has dropped the previously identified option to provide a new crossing alongside the existing Dartford Crossing. Instead, Highways England is advancing a series of schemes that span from the east of Gravesham to Tilbury.
Why do we need a new crossing?
Highways England finds that the existing crossing has insufficient capacity. It is heavily congested and predicted to only get worse. By 2025 stretches of the road will be at capacity within the peak and inter-peak periods. Add to this an average of 300 unplanned closures per year and it is easy to see why the existing crossing, is deemed to offer little in terms of resilience.
What work has been undertaken to date?
The Department for Transport consulted on five options in 2009, which was subsequently reduced to three options in 2013. It was not until 2014 that Government advised that Option A (at the existing crossing) and Option C (east of Gravesend and Tilbury) would be the front-runners.
What is Highways England now consulting upon?
The Former Option C route is now presented in three variations, re-branded as Route 2, Route 3 and Route 4 (as shown overleaf). Option 1 (now known as Option A) has been dismissed by Highways England as it scores poorly from a traffic perspective and, ultimately, is not deemed to alleviate the problems at the existing crossing.
What option does the DfT prefer?
The Highways England consultation document suggests that Route 3 is the favoured option. It is the shortest of the routes and, therefore, considered to be the lowest-cost option. It would also provide a completely new 70mph solution so is found to score highly in terms of “quality”. Conversely, Route 2 has the greatest noise and air quality impacts and heavily impacts on heritage and flood mitigation assets. Its construction would also heavily disrupt operations at the Port of Tilbury. Route 4 is the longest, and most expensive, but could support future residential development.
Bridge, bored tunnel and immersed tunnel?
Highways England has confirmed that all three crossing types are all technically feasible. Highways England state that a bridge could cause a number of negative impacts on the nearby SPA, RPSB reserve, and local wildlife sites. Therefore, the legal viewpoint is that a bridge is very unlikely to be deliverable. Highways England find a tunnel would offer a less environmentally damaging option; however, it does pose risk from a ground conditions perspective. Lastly, an immersed tunnel is likely to cause environmental harm and the potential hydrodynamic effects are uncertain. Highways England has been advised that from a legal perspective an immersed tunnel is very unlikely to be deliverable in this location.
How much would the options cost?
Highways England advise that the new road would be approximately 15 miles long and consist of a 2-mile twin bored tunnel. During development of the design, consideration will be given to the provision of an additional lane in each direction of the tunnel to allow for future-proofing. Highways England find that Route 2 would cost up to £5.98 billion; Route 3 would cost up to £5.94 billion, and Route 4 would cost up to £6.39 billion.
What do the relevant Local Authorities think about the proposals?
Thurrock Council, Gravesham Council and Dartford Council have all previously voiced their concerns against any new crossing being implemented through their respective boroughs, and whilst Dartford are less effected by the latest proposals, further comments from Thurrock and Gravesham are awaited following the latest announcement by Highways England. However, it is expected that both authorities will be strongly opposed to the preferred option.
What are the next stages in the process?
Consultation on the Lower Thames Crossing ends on 24 March 2016. If you wish to make representations or discuss any impact of the consultation document then please contact us at info@iceniprojects.com.
It is expected that the Government will make an announcement later this year to confirm the route, location and type of crossing.
When might it be built?
To download our summary sheet, please click here.