A6 Randalstown to Castledawson Dualling

A6 Randalstown to Castledawson Dualling

DCIM100MEDIADJI 0115JPG | BRE Group

CEEQUAL Excellent Sustainability rating (85.4%) – Whole Team Award
Version 5, April 2022 | N. Ireland

Assessors: Peter Shaw, AECOM
Verifier: Dion Williams, DWW Consulting Ltd.
Designers: Graham Farrans Joint Venture
Contractor: Graham Farrans Joint Venture
Client: Department for Infrastructure Northern Ireland

Project Summary

Delivered by the Department for Infrastructure the A6 Dualling Scheme upgrades 14.7 kilometres of Transport Corridor between Randalstown and Castledawson, a route used by 20,000 vehicles each day, which historically experiences congestion at key times.

Graham Farrans Joint Venture was awarded the contract for this essential work, which brings long term social and economic benefits to the local area.

The flagship investment of £185m strengthens the links between Belfast and Derry/ Londonderry and brings the long-term benefits to road users and the local community of reduced journey times and improved road safety.

Project Management

The management of the potential environmental impacts was a key part of the scheme from the outset. As part of the design environmental management plan, environmental risk and opportunity assessments were developed early in the design to address likely impacts and seek to mitigate these where possible.

These assessments also served to highlight potential environmental enhancements and incorporate these into the designs and contract requirements. Graham Farrans Joint Venture (GFJV) developed the Construction Environmental Management Plan incorporating potential impacts and enhancements and introduced processes to manage these items during construction.

People and Communities

The length of the scheme was almost 15km and therefore impacted on many different landowners, communities and habitats. Throughout all stages, community consultation was a key priority, and this included leaflet drops, public exhibitions and home visits. During construction a dedicated website was developed for the scheme to alert the communities to road closures and scheme related news.

During planning and design an environmental working group was established to meet regularly and discuss impacts and opportunities for the scheme. This included statutory bodies and key stakeholders such as voluntary groups and local charities. The working group continued into the construction stage and allowed for updates on the programme and gave a forum to address the Contractor directly.

In terms of innovation, one of the important neighbours on the scheme were the Whooper Swans. The Whooper swans are a selection feature of the Lough Neagh and Lough Beg Special Protected Area. The Lough Beg site is the single most important in Northern Ireland for the Whooper Swans who migrate south from Iceland for feeding every winter until their return trip in April.

Protection of the overwintering Whooper Swan population was of paramount importance and was stressed throughout the initial Project EIA. GFJV supported the ‘Working Group’, consisting of representatives from RSPB, BTO, WWT and independent specialists who advised on the methodologies and working times to minimise the risk of disturbance and ways to enhance the local habitat to benefit the swans.

The Contractor therefore developed an innovative and detailed RAMS document in order to minimise any potential nuisance caused by construction activities and ensure that the Whooper Swans were not disturbed as far as possible.

The Whooper Swan Protocol was issued to all operatives wishing to enter the restricted zone during the embargo period of October to March. This was part of the mitigation to ensure that there was zero to negligible disturbance to the local whooper swan population. Contained within the protocol was the need for operatives to enter the site before first light, enter only on foot and do not wear PPE.

Protection of the overwintering Whooper Swan

Land use and Landscape

Following DRMB procedures a 3-stage process was followed for route selection. From the 8 routes initially considered, a preferred option was taken forward on the basis of an assessment and consultation process.

Given the linear nature of the project, a central location was chosen, and existing offices were hired to form the compound. Borrow pits were used throughout the scheme; these provided clay and granular fill through excavation, and could then be filled with unsuitable material, topsoiled and returned to useable greenfield land. This process saved transporting Class 4 unsuitable material to landfill.

Sustainable Land use and Landscape

Ecology and biodiversity

As described, Whooper Swans were known to overwinter close to the site in 2003 and, given their protected status, have been a major part of the scheme ever since.

A Whooper Swan Working (WSW) Group was established, comprised of the Department of Agriculture, Environment and Rural Affairs (DAERA) Countryside Management, DAERA Conservation Designation & Protection Compliance team, the University of Exeter, Whooper Swan Consultant, RSPB, WWT, DFI Roads, AECOM and GFJV.

The purpose of the group was to explore options for habitat enhancement to improve the long-term viability of the Whooper Swan winter feeding site. Toolbox talks were developed and delivered to all staff on measures to lesson the nuisance of road construction including: avoiding entering certain fields; keeping equipment/ plant/ people low key until the whooper swans had moved out of immediate area; no works to take place within fields where swans were present; continual monitoring of the swans throughout.

The Considerate Constructors Scheme Report noted

“To add further value, whooper swan counts for winter 2017/2018 were reported as the second highest numbers to date for the Toome Complex. GFJV demonstrated original thinking by giving priority to the protection of the whooper swan from construction works and by enhancing the Toome Complex to improve the long-term viability of the winter-feeding site. This Considerate Practice leads the way in environmental sustainability and gives a real long-term improvement to the overall image of construction.”

Additionally, Sand Martins were discovered within the site and found to be nesting in the borrow pits, which had to be closed for a time until the Sand Martins had left.

Ecology and biodiversity Sand Martin nesting borrow pit

Water environment

The scheme includes for detention basins throughout in order to attenuate flows and discharge at greenfield runoff rate. The outfall pipe from the basin is designed on an upward slope so that any floating hydrocarbons will be captured within the basin above the outfall and can therefore be extracted easily. Basin are lined to prevent the possibility of groundwater being polluted, and this lining extends in the ditches down to the nearest major watercourse.

During construction, GFJV constructed silt lagoons, silt fencing and other scour protection measures to ensure that local freshwater features were protected throughout the construction period, and especially during the topsoil strip. GFJV constructed bunds between the haul route and nearby watercourses to delineate the access roads and protect local watercourses.

Water environment - Silt lagoon

Physical resources use and management

GFJV implemented and monitored a large number of different metrics on the scheme by way of various policies and targets to ensure that physical resources were managed appropriately including invasive species, pollution control, carbon, CCS, waste, green travel, biodiversity, resource management, water quality, etc.

GFJV developed a Mass Haul plan to manage site-won materials and ensure that materials travelled the least distance possible to where they were needed at all times. The management of these materials in this way led to carbon savings estimated at 23,178.6 Tonnes of CO2 when compared to disposal offsite.

Transport

While there were many highly specified design features along the scheme, one aspect of design which went far beyond the required standards was at the Castledawson Roundabout. The standards required at-grade crossings for pedestrians; however during the planning and design stages this was upgraded to instead provide a bridge crossing which was subject to a standalone planning application.

The result is a focal point for the junction which provides a route for pedestrians / NMUs to traverse the junction safely.

Sustainable Transport - Castledawson Junction

What were the main challenges for the project and how were these overcome?

As described, the main challenge on this project was the proximity of the site to overwintering Whooper Swans. One of the commitments in the Environmental Statement was to monitor the distribution of the Whooper Swan population within the immediate area, and this has been undertaken on a continual annual basis since winter 2005/06, and will continue to do so until the end of the 2023/24 season.

The Working Group set up to coordinate and manage the scheme implications has been meeting since March 2016, and has met 44no. times to date, and has secured land management agreements and field size adjustments.

A Whooper Swan Management Scheme (MS) has been set-up to run for a 5-year period, with nine landowners (within the Management Scheme boundary) signed-up for Year 3 (representing c.140ha of the 252ha of land within the MS area). Several field amalgamations totalling over 20ha have been achieved. Nine landowners within the complex are currently signed-up to a Whooper Swan Management Agreement, whereby sheep are to be excluded from their fields between 01 October and 31 March. In the case of cattle, the exclusion period is from 01 November to 31 March.

Environmental Statement Whooper Swan Management Scheme

What were the drivers and perceived benefits for undertaking a CEEQUAL assessment on this project?

Certainly the benefits of CEEQUAL were in ensuring that the scheme promoted sustainable practices especially in material movements on the site, protection of biodiversity and engagement with the local communities.

How did the use of CEEQUAL influence the outcomes of the project? What was done differently because of the CEEQUAL process?

The inclusion of CEEQUAL leads to monthly meetings in order to complete the assessment. While this alone is self-fulfilling, the meetings themselves result in actions being taken elsewhere. During planning and design, further drainage checks were completed to ensure resilience in the system and ensure that rainfall events beyond those designed for would be managed appropriately.

CEEQUAL influenced a large number of factors during construction such as the creation of bespoke haul plans to indicate location, type and quantities of material being distributed throughout the site, the community benefits of the scheme and the lasting positive impact of the works.

What elements of this project highlight best practice and innovation?

Material efficiency on the scheme is a showcase for how materials, if planned and designed correctly, can be used in a highly sustainable manner.

Constructing a scheme adjacent to Lough Beg SPA also required some innovative techniques and ideas.

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