1. Introduction

1. Introduction


This brochure is the Non-Technical Summary of the Environmental Statement for the Forth Replacement Crossing project (FRC).

The FRC is a major road infrastructure project proposed by Transport Scotland, an agency of the Scottish Government. The project is driven by uncertainty over the future viability of the existing Forth Road Bridge, and is designed to safeguard this vital connection in Scotland’s transport network. It comprises a new cable-stayed bridge across the Firth of Forth, to the west of the existing Forth Road Bridge, and associated new and improved road infrastructure to the north and south of the bridge. The route of the proposed bridge and connecting roads is shown below.

The route of the proposed bridge and connecting roads

The proposed scheme will retain the existing Forth Road Bridge as a public transport corridor for use by buses, taxis and other specified users and for continued use by pedestrians and cyclists. The new bridge (referred to as the main crossing) will be used by all other traffic including private cars and heavy goods vehicles. Emergency vehicles will be able to use either bridge.

The proposed scheme will be authorised through a Hybrid Bill introduced in November 2009 and processed by the Scottish Parliament. A Hybrid Bill is a public Bill which affects a particular interest of a person or a body. It generally relates to a development project.

It is anticipated that construction will start in 2011 and that the FRC will open in late 2016.

Environmental Impact Assessment

An Environmental Impact Assessment (EIA) of the proposals is required under European legislation and by the Scottish Parliament to identify the potential environmental effects of the proposals. European and UK legislation also require an assessment of the effects of the proposals on internationally designated sites for nature conservation in the vicinity of the proposed scheme. Reports, which are called Reports to Inform an Appropriate Assessment, have been produced for these sites. Information from these separate reports is summarised in the Environmental Statement.

The Environmental Statement reports the findings of the Environmental Impact Assessment work carried out on the FRC proposals during 2008 and 2009. This Non-Technical Summary presents the key issues identified in the Environmental Statement, including the beneficial and adverse impacts considered to be of particular importance. The Environmental Impact Assessment process has also considered the likelihood that, in the absence of a replacement crossing, there will be a need for substantial repairs and refurbishment on the Forth Road Bridge, with associated significant impacts relating to the disruption created by these works.

Further details about the FRC proposals and their impacts can be found within the full text of the Environmental Statement.

Need for the Scheme

The FRC is required because of the uncertainty over the condition and long-term future of the existing Forth Road Bridge. The crossing over the Forth is critical to the east of Scotland economy, providing a vital link between Edinburgh, the Lothians and Fife.

The condition and operational capability of the Forth Road Bridge have deteriorated over time, primarily because of increased traffic and the effects of weather on the bridge. One of the main concerns in recent years has been the condition of the main suspension cables and whether the bridge can continue as the main crossing for all traffic, as well as other ongoing maintenance issues.

In February 2008, a study by the Forth Estuary Transport Authority (FETA) reported that it would be possible to replace the bridge’s cables, however this would not be feasible without a replacement bridge being in place because of the severity of the impact on road users and the wider economy. Studies into the rate of cable deterioration are ongoing and the preliminary findings have been taken into account in the design and programming of the FRC proposals.

The FRC has been identified as a key strategic investment project in Scotland’s national transport network in the Strategic Transport Projects Review (STPR) undertaken by Transport Scotland in December 2008, and the National Planning Framework (NPF2) published by the Scottish Government in June 2009.

Scheme Objectives

There are eight specific transport planning objectives for the FRC which have underpinned the work on the proposals. These are to:

  • maintain cross-Forth transport links for all modes to at least the level of service offered in 2006
  • connect to the strategic transport network to aid optimisation of the network as a whole
  • improve the reliability of journey times for all modes
  • increase travel choices and improve integration across modes to encourage modal shift of people and goods
  • improve accessibility and social inclusion
  • minimise the impacts of maintenance on the effective operation of the transport network
  • support sustainable development and economic growth
  • minimise the impact on people, and the natural and cultural heritage of the Forth area.

Artists impression

Alternatives which have been considered

A Forth Replacement Crossing Study (FRCS) was undertaken during 2006 and 2007 to identify the most favourable option for a replacement crossing.

Five potential crossing corridors were identified from an original list of 65 potential crossing solutions. Each of the five corridors was appraised for its suitability for a tunnel or a bridge crossing. The appraisal process considered environmental issues alongside other factors, and concluded that a bridge option in a corridor east of Rosyth and to the west of South Queensferry was the best option due to lowest construction costs, shortest construction programme, lowest construction risk and greatest economic benefit.

Main Crossing Options

Development of the selected bridge (the main crossing) took place during 2008 and 2009. Initially a design was considered which incorporated a dual two-lane motorway, footway/cycleway and a public transport corridor.

The work undertaken by FETA during 2008 indicated that the main cables of the Forth Road Bridge were not deteriorating as rapidly as anticipated and confirmed that it would be feasible to replace them, if necessary, following the completion of a replacement crossing. FETA has now installed dehumidification equipment to arrest or slow down the rate of corrosion on the main cables of the Forth Road Bridge. An assessment by Transport Scotland established that the Forth Road Bridge, once relieved of general traffic, would be capable of accommodating public transport, pedestrian/cycle facilities and of being adapted for tram/light rail use at a later date. In addition, assuming that FETA’s dehumidification scheme is successful and with all general traffic transferred to the replacement crossing, the main cables of the Forth Road Bridge may not require replacement for the foreseeable future.

These findings were incorporated into the project, allowing a narrower, more cost-effective cross-section for the main crossing to be adopted. A range of deck and tower options were considered with aesthetics, construction and cost all taken into account. The selected option was a single deck, twin corridor bridge with single column towers.

Connecting Road Options

In 2008, a review of route corridor options was undertaken to consider potential road connections to the north and south of the Firth of Forth that could connect the recommended bridge corridor to the existing road network. Nine route corridors were identified for assessment: three options to the north of the Firth of Forth (providing connections to the A90/M90) and six options to the south (providing connections to the A90, M9 Spur and M9).

The assessment of the route corridor options considered environmental impact, geotechnical issues (such as the presence of old mineworkings), cost and how successfully the routes would operate as part of the road network. Four options were taken forward for more detailed assessment and the overall recommendation was to develop options north and south of the Firth of Forth which would make best use of existing infrastructure, enable new and improved junction arrangements, minimise environmental impacts and which were the most affordable and economically efficient.

The proposals were further refined between August 2008 and April 2009. Feedback from the public and other project stakeholders was incorporated into this refinement process. This design process resulted in the proposed scheme reaching the stage described and assessed in the Environmental Statement.

The Proposed Scheme

The proposed scheme can be separated into the following three main sections, with overarching traffic management measures supported through the use of an Intelligent Transport System (ITS) which will operate between Halbeath Junction on the M90 and Newbridge Junction on the M9:

  • the main crossing
  • road connections north of the main crossing to Admiralty Junction (M90 Junction 1)
  • road connections south of the main crossing to Scotstoun Junction (A90/M9 Spur), together with enhancement to M9 Junction 1a.

The Main Crossing

The main crossing will be located upstream of the Forth Road Bridge and will consist of a three-tower, cable-stayed bridge and approach viaducts. The total length of the main crossing is approximately 2.7km. This includes the bridge plus the north and south approach viaducts. It will be a dual two-lane motorway with hard shoulders. There will be adequate clearance (more than 47m) under each of the two main spans of the bridge to maintain access for shipping. The main crossing will include wind shields.

The Forth Road Bridge will become a public transport crossing alongside the main crossing.

Northern Connecting Roads

North of the main crossing, the Ferrytoll Junction will be fully reconstructed to cater for all local and longer-distance traffic movements, pedestrian and cyclist movements, whilst also maintaining access to the existing Forth Road Bridge.

The B981 will be realigned over part of its length and will join Ferry Toll Road, west of the Dunfermline Wastewater Treatment Works. This will maintain access to North Queensferry during the construction period and improve the operation and safety of Ferrytoll Junction. Castlandhill Road will also be realigned to separate local traffic from A90 traffic.

Southern Connecting Roads and M9 Junction 1a

To the south of the main crossing, a new 3.1km section of dual carriageway will be built around the west and south of South Queensferry to join with the A90 and M9 Spur at the Scotstoun Junction. A new Queensferry Junction will link local roads (including the A904) to the new road infrastructure and the main crossing, whilst maintaining pedestrian and cyclist routes.

From the Queensferry Junction to the Scotstoun Junction, the road will be dual three-lane carriageway with hard shoulders, constructed to motorway standard. The additional carriageway width means that the existing A8000 overbridge will require to be reconstructed. Dedicated public transport lanes will be provided from the Forth Road Bridge eastwards in the direction of Edinburgh using the A90, and from the A90 to the A8000 westwards to join a proposed bus priority scheme on that road. There will be no change to the existing A90 from the Scotstoun Junction into Edinburgh.

Junction 1a on the M9 will be redeveloped to provide two general traffic lanes on the existing south-facing slip road and loop to help traffic flow and make better use of the current junction. New west-facing slip roads will be added to better serve West Lothian traffic. The M9 will be widened to provide four lanes of traffic in the southbound direction to complement the proposed improvements to this junction. An additional lane on the M9 will be added in the northbound direction between the River Almond Bridge and Junction 1a to help diverging traffic.

Traffic Management Measures

Traffic management measures will be implemented between Halbeath Junction on the M90 and Newbridge Junction on the M9. Overhead gantries and Intelligent Transport System (ITS) components will provide lane control signals, mandatory (variable) speed limits, ramp metering (to regulate the flow of traffic entering the mainline from a slip road) and other functions to improve the operational efficiency of the road network and reduce congestion.


It is anticipated that the main line will be lit in the south between the Scotstoun Junction and the main crossing, as will the section between the main crossing and Admiralty Junction in the north. The side roads in the vicinity of Ferrytoll and South Queensferry junctions are also expected to be lit. The impact of extending the lighting over the full length of the scheme was assessed.

Delivering the Proposals

The Environmental Statement presents the assessment of the project as described in Chapter 4 (The Proposed Scheme). The design of the project may be refined but will still be deemed to comply with the Environmental Statement provided that such refinements incorporated in the design will be subject to environmental review to ensure that residual impacts will be no worse than those reported.

Overview of the Environmental Impact Assessment Process

The Environmental Impact Assessment has been undertaken as an integral part of the design process, informing decisions on the proposals as they were developed. Environmental constraints and issues were identified and incorporated into the decision-making process throughout. Information gathered in the extensive surveys undertaken for the scheme was used in the assessment.

The aims of the environmental impact assessment are to:

  • gather information about the environment of the area in the vicinity of the scheme and identify environmental constraints and opportunities that may influence or be affected by the proposed scheme
  • identify and assess potential environmental impacts
  • identify and incorporate measures into the scheme design and operation to avoid, reduce or offset adverse impacts and enhance beneficial impacts
  • assess the residual effects of the scheme.

Intelligent Transport systems

Impacts were assessed by comparing them to the baseline conditions which would exist if the scheme did not go ahead. For the purposes of the Environmental Impact Assessment, it was assumed that the Forth Road Bridge and the existing road network would continue to be used if the FRC proposals were not implemented. In addition, it is recognised that if a new crossing is not provided, it is very likely that an extended period of major, very disruptive repair works on the existing bridge would be required. A supplementary assessment of the impact of these works was therefore undertaken and consideration given to the implications for the findings of the Environmental Impact Assessment if these works were included in the baseline conditions.

Consultation and Scoping

As part of the design development and assessment process, a comprehensive consultation exercise was carried out with more than 160 consultees, including local authorities, Historic Scotland, Marine Scotland, Scottish Environment Protection Agency (SEPA), Scottish Natural Heritage (SNH), relevant community councils and more than 100 landowners and tenants. Public exhibitions were held in January 2009 as part of a programme of ongoing public engagement and consultation.

The purpose of the consultation exercise was to:

  • ensure that statutory consultees, other bodies with a particular interest in the environment, and members of the public were informed of the proposals and provided with an opportunity to comment
  • collate baseline information regarding existing environmental site conditions
  • obtain input to the identification of potential impacts and the development of appropriate mitigation, including design development
  • inform the scope of the Environmental Impact Assessment.

The FRC project team has worked closely with all the key stakeholders to develop a scheme that aims to reduce environmental impacts by avoiding sensitive features and through careful design. Stakeholder feedback was reviewed by the assessment team and incorporated into the assessment and design process where appropriate.