A479 Talgarth Relief Road and Bronllys Bypass

CEEQUAL Excellent (82.9%) – Whole Project Award
Version 3, Mar 2009 | Talgarth, Wales

ClientWelsh Assembly Government
Design & Build ContractorBAM Nuttall Ltd
DesignersHyder Consulting
Employer’s AgentParsons Brinckerhoff/WYG Planning
Assessor: Delyth Toghill

Project Summary

BAM Nuttall Ltd were awarded the Design and Build Contract for the A479 Talgarth Relief Road and Bronllys Bypass by the Welsh Assembly Government in early 2006, with Hyder Consulting acting as their designers, covering all disciplines, including environmental design, earthworks, drainage and highways aspects.

The scheme lies partly within the Brecon Beacons National Park and therefore required sensitive landscape treatment in order to achieve successful integration with the surrounding countryside. This was achieved through a combination of careful selection of the highway alignment, recreation of existing landscape features (i.e. hedgebanks and hedgerows) and appropriate planting.

Acquisition of adjacent land and remnant field corners as part of the Compulsory Purchase Order (CPO) for the project was also a key factor in the project’s development. This allowed earthworks to be slackened (in comparison with normal engineering slopes), profiles to be varied and also provided room for additional landscape planting. Overall, this has resulted in a more natural roadside landscape.

The CEEQUAL Award not only recognises the efforts taken to address landscape issues, but also work undertaken throughout all stages of scheme development in relation to archaeology, ecology and sustainable construction in general.

Talgarth Gateway feature

Talgarth roundabout

Achievements

Archaeology

A series of archaeological excavations was conducted at the outset to investigate historic use of the scheme footprint. Finds included items of Roman pottery and a Bronze Age cist.

Ecology

Before site clearance work began, extensive ecological surveys were carried out to ensure that the site was clear of ecological constraints. Early surveys also helped to inform the design of detailed mitigation measures.

The Talgarth section of the scheme includes mitigation for a wide range of protected species, including lesser horseshoe bats, badgers, otters and dormice. Where possible, mitigation measures have been combined and this is best demonstrated at Pendre Culvert, where an oversized culvert approximately 2m in diameter was provided. The culvert was designed to allow lesser horseshoe bats to safely cross the line of the road, but it also accommodates a seasonal watercourse, mammal ledges for badger and otter and a high-level dormouse ledge to link habitat on each side of the new road.

Monitoring of the mitigation measures during construction and post-construction has shown that lesser horseshoe bats are using the bat underpass. There is also evidence that badgers and otters are present.

In addition to the dormouse shelf, the scheme includes an innovative dormouse overhead crossing at Pendre, intended as a long-term mitigation measure to address potential fragmentation effects of the road. The design of the Pendre Culvert and headwall were specifically altered to allow mature Oak trees to be retained, thereby ensuring the best possible connection with adjacent vegetation.

Landscape

As part of the landscape proposals, grass seed was sourced from local species-rich meadows, with help from the Countryside Council for Wales (CCW), to ensure that local provenance material was used.

In total, approximately 20ha of species-rich grassland were created as a result of the scheme.

Water Management

Watercourses that cross the scheme or run alongside are tributaries of the River Wye Special Area of Conservation (SAC). During construction, a surface water management plan based on Sustainable Drainage (SuDs) principles was developed in conjunction with the Environment Agency to ensure that drainage from the scheme (in particular suspended solids) did not affect the SAC. The same ponds that were used during construction now form the attenuation ponds for the operational scheme.

Post-construction monitoring of aquatic invertebrates has shown that fresh-water crayfish continue to thrive within these watercourses. Indeed these populations are possibly some of the strongest in the National Park.

Sustainable Construction

Other key features of the scheme that have contributed to the high CEEQUAL score include the following:

  • Earthworks balance – excavated material was re-used within the scheme or within landscape areas, thus reducing vehicle movements.
  • Stone from a local quarry was used to face Pendre Culvert, gateway entrances and feature walling within Talgarth, reinforcing local character and reducing transport impacts.
  • Retention of mature trees – including trees on both the Talgarth and Bronllys sections of the scheme.
  • Extensive involvement of the local community and statutory consultees took place during development and construction of the scheme, including visits to the site by local school children.
  • A detailed Construction Environmental Management Plan (CEMP) was developed and implemented, ensuring that commitments made within the Environmental Statement and Public Inquiry were addressed.
  • Implementation of a 5-year aftercare period – including long-term management and monitoring of the effectiveness of mitigation measures.
Pendre culvert

Dormouse crossing

CEEQUAL insights and case studies

Browse the latest insights, thinking and case studies from CEEQUAL

 

Skonviksvagen-featured

Stockholm Metro Nacka project awarded Excellent

The Stockholm Metro Nacka Extension is awarded Excellent, showing Stockholm's commitment to sustainable urban development ...
breeam-infrastructure-stockholm-metro-extension-sofia

Stockholm Metro Sofia access tunnel a BREEAM Infrastructure success

BREEAM Infrastructure is helping Stockholm expand it's Metro to boost public transport and support sustainable urban growth ...
Stockholm Extended Metro access tunnel Sundstabacken achieves CEEQUAL Excellent rating

Stockholm Extended Metro access tunnel Sundstabacken achieves CEEQUAL Excellent rating

The Stockholm Metro extension aims to boost public transport capacity by growing the system. Building metro infrastructure in a dense ...
E08-Forberedende-arbeider-BREEAM Infrastructure

Preparatory works for the new water treatment system in Oslo achieves BREEAM Infrastructure Excellent rating

The preparatory works for the new water treatment system in Oslo, ordered by 2028 achieves BREEAM Infrastructure Excellent ...
Ramsdal bridge BREEAM Infrastructure

E39 Mandal øst – Mandal

E39 Mandal East- Mandal city consist of a 7 km long four lane highway that together with the new E39 ...
BREEAM Infrastructure Bybanen D18 Sykkelvei Kronstadtunnelen

Bybanen D18 Sykkelvei Kronstadtunnelen

Project D18 Sykkelvei Kronstadtunnelen is part of the Bybanen-light rail construction stage 4 development scheme. This is the largest development ...

Get in touch

Contact us now or call us on +443330147880 if you would like to talk to our team about how CEEQUAL can support you.

Tags