Forth Replacement Crossing Project - Intelligent Transport System

Forth Replacement Crossing Project - Intelligent Transport System


L Shackman, Tranport Scotland, UK; K Carpenter, Tim Barber, Jacobs Arup, UK


The Forth Replacement Crossing (FRC) Project, through utilising technology, seeks to reduce congestion and emissions and improve road safety. The provision of ITS will improve traffic flow and reduce congestion for traffic and through the scheme.


The Forth Replacement Crossing (FRC) Project is the most significant Scottish transport project in a generation and is vital to Scotland's economic future. This project, through utilising technology, seeks to reduce congestion and emissions and improve road safety.

The main suspension cables of the Forth Road Bridge (FRB) are showing significant signs of deterioration as a result of corrosion. The rate of deterioration, as assessed at the latest inspection, suggests that restrictions on Heavy Goods Vehicles using the bridge may need to be applied from as early as 2014 but more likely sometime between 2017 and 2021 with the possibility of full closure to follow this. Though the suspension cables can be repaired the work to replace them would be a very major undertaking and would cause sustained and significant periods of disruption.

A technical assessment was undertaken to assess the capability of the FRB. This concluded that, if the cable deterioration was stabilised, the bridge could support the reduced loading of public transport (including, in the future, trams), pedestrians and cyclists.

The Forth Replacement Crossing project comprises a new crossing of the Firth of Forth with connecting roads at either end. To maximise the benefits of the new bridge and connecting roads, the works include provision of a state-of-the-art Intelligent Transport System (ITS) extending from Halbeath on the M90 over the new bridge to Newbridge on the M9, a distance of 22km. This system will be the largest installation of ITS in Scotland, incorporating approximately 60 gantry signs.

The provision of ITS will improve traffic flow, reduce congestion and improve road safety for traffic approaching and through the scheme. The ITS will be designed with a development and technology refresh regime so that the operator tools remain effective as traffic demands change in future years.

The FRC's ITS will provide complementary measures to support cross-Forth travel during normal and abnormal conditions on the network and in the wider context allow the corridor to be managed within Traffic Scotland's trunk road network.
The design takes account of the specific strategic transport planning objectives developed for the project as follows:

o Maintain cross-Forth transport links for all modes to at least the level of service offered in 2006

o Connect to the strategic transport network to aid optimisation of the network as a whole;

o Improve the reliability of journey times for all modes of transport;

o Increase travel choices and improve integration across modes of transport to encourage modal shift of people and goods

o Improve accessibility and social inclusion

o Minimise the impacts of maintenance on the effective operation of the transport network

o Support sustainable development and economic growth

The ITS will help to promote the development of an integrated and environmentally friendly transport system, assisting economic growth and improving the throughput of traffic. It will remove bottlenecks, increase capacity, provide better connectivity with key destinations including the Port of Rosyth and Edinburgh Airport, improve the management of accidents and help reduce delays caused by incidents. It will provide a high standard of driver information improving network resilience and enable greater certainty in journey time estimates. By control and management of traffic flows there will be improvements to road safety together with a commensurate reduction in emissions, aiding the carbon footprint.

By using detection technology rather than carriageway widening the Project minimises adverse effects on the environment. On completion of the scheme there will be 2 lanes in each direction for private traffic over the Forth, as at present, additional capacity is created by managing the traffic flows using the ITS system. In addition bus hard shoulder running will be incorporated during construction on the M90 southbound and permanently on the M9 Spur/M9 southbound to Newbridge with ITS measures in place to manage the use of the FRB as a dedicated public transport corridor after the opening of the new crossing.

The project is being progressed as three contracts each of which includes the installation of a major part of the ITS system. The tender process for each of these contracts is currently ongoing. It is fully intended that by October 2011 construction will have commenced on each and that in due course all ITS elements of the project are operating effectively, having been constructed on time and to budget


Association for European Transport