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The Edit

ROADS

Landslides close A83 at Rest and Be Thankful as plans for long term protection work gather pace

Scotland’s A83 Rest and Be Thankful section closed on the weekend of 7 and 8 October as heavy and persistent rainfall triggered several landslips, blocking the route.

The area around the road had 160mm of rain in 36 hours, causing seven landslides on the A83 between Inveraray and Tarbet.

Transport Scotland stated that by 9 October its contractor Bear Scotland had removed 9,500t of debris from the A83. It said it was likely that a further 2,000t of material on the hillside would also have to be removed before the road can safely open.

The Rest and Be Thankful viewpoint is the highest point on the A83. The road runs through a valley and links the west coast and the Highlands to Scotland’s central belt. It has a high risk of landslides and debris flow hazards, which have increased in recent years due to the frequency of heavy and prolonged periods of rain.

In June, Transport Scotland announced plans to build a £470M debris flow shelter to protect the Rest and Be Thankful section. The scheme comprises a 1.4km long, open-sided tunnel, costed at between £405M and £470M. Its selection followed design and assessment work on five route options in the Glen Croe valley.

In June, transport minister Kevin Stewart said: “Work will now be taken forward at pace to further develop our proposals, including the detailed development and assessment of the preferred option along with the preparation of an environmental impact assessment, draft road orders and draft compulsory purchase orders.”

AIRPORTS

Work starts on major Polish airport to be completed by 2028

Work has started on a new airport in Poland, billed as the largest transport investment in Europe, costing £7bn. The airport is known as Centralny Port Komunikacyjny.

Ground investigations have started at the site 40km west of Warsaw and more than 1,000ha of land has been purchased.

The search for a development partner is also underway. The first phase of the scheme is due for completion in 2028 and includes two runways and terminal infrastructure for up to 40M passengers annually. Expansion is also planned as demand grows.

The ambition is to build two further runways and serve 100M customers annually. Up to 2,000km of new railway could be built as part of an effort to make the airport a multimodal transport hub.

TUNNELS

US joint venture to build major Washington DC sewer tunnel

A joint venture between CBNA and Halmar has won the $819M (£671M) contract to design and build a major new sewer tunnel in Washington DC.

NCE’s sister title Ground Engineering reports that the 8.9km long Potomac River Tunnel will control combined sewer overflows into the Potomac River in Washington. The 5.5m diameter tunnel will run beneath the city’s Georgetown waterfront, along the edge of the National Mall and East Potomac Park, past Hains Point and connect by gravity to the existing Anacostia River Tunnel.

Construction requires two tunnel boring machines. Starting from West Potomac Park, one will move south through mostly soft ground. The other will head north through rock.

Florida-based CBNA is part of Bouygues Construction and specialises in major civil and building projects. New York-based Halmar specialises in highway and bridge construction.

BRIDGES

Bridge opening delayed

Grade II listed Corporation Bridge in Grimsby, North East Lincolnshire will no longer reopen as scheduled in December 2023 after closing for maintenance in February. Severe corrosion was discovered on its steel underside spans.

North East Lincolnshire Council confirmed that grit blasting to remove paintwork revealed the condition of span one of the structure, with corrosion accelerated by sea water flowing beneath it.

STRUCTURES

East Coast Main Line bridge closed for emergency repair work

Plessey Viaduct on the East Coast Main Line in Northumberland has partially closed so Network Rail engineers can carry out urgent repairs to a moved parapet.

The viaduct carries the line over the River Blyth between Cramlington and Morpeth and is only be able to carry trains over in one direction since the parapet damage was discovered during planned engineering works.

Network Rail teams including AmcoGiffen engineers discovered that the parapet, a safety feature installed on the stone structure, had moved. Work stopped and specialist structural teams attended the site to assess repair options.

The site location, viaduct design and the heavy machinery needed mean that moving the parapet back to its original location is unviable.

Network Rail structural engineers and external specialists are working on different options to repair the structure.

ENERGY

Australia's Snowy 2.0 energy scheme is almost half finished

Australia’s Snowy 2.0 renewable energy scheme is heading to the halfway mark as excavation of its central 250m long underground power station cavern gets underway. The project has experienced cost hikes and delays.

It was originally proposed in 2017 by Australia’s then-prime minister Malcolm Turnbull as an AUS$2bn (£1bn) project, but by August this year its budget had risen to £6bn.

Project promoter Snowy Hydro has confirmed the scheme is 40% complete, with excavation of the 250 m-long underground power station cavern and tailrace tunnel underway. A tunnel boring machine will excavate the inclined pressure shaft into the cavern.

The 1.45km long shaft will be excavated at a 47% incline using an 11m diameter TBM, an operation described by Snowy Hydro as “without precedent internationally.”

WATER

Anglian Water's 68km long pipeline wins council backing

Anglian Water’s proposals for a 68km pipeline between Bury St Edmunds and Colchester are inching forwards after being approved by Babergh and Mid-Suffolk district councils. Approval from Colchester Borough Council is also required before work, originally scheduled to start this year, can begin.

The pipeline is the southernmost section of a wider £400M scheme to install 500km of interconnecting pipes and associated pumping equipment.

The scheme will also include break tanks and pumping stations at key locations to ensure water can be moved efficiently.

The water main network serviced by the wider pipeline scheme will cover more than 300km from North Lincolnshire, through Cambridge, to Suffolk and Essex and will bring water from the North to the South and East of England, which are at risk of running out of water by 2030.

STRUCTURES

Belfast's Casement Park stadium plan hits funding hurdles

European football’s governing body, Uefa confirmed in October that the UK and Ireland will host the 2028 European Football Championships, with Belfast’s Casement Park stadium as a venue. However, proposals to redevelop the derelict stadium have been be dogged by funding uncertainty.

Planning for the structure’s redevelopment as a 40,000-capacity venue began in 2009. This was blocked by a High Court ruling in 2014 after resident opposition.

A 34,500-seat plan was unveiled in 2016 and gained planning permission in 2021. The scheme’s initial budget was £77M, but in 2021 former Northern Ireland first minister Paul Givan put the figure at up to £150M.

The Department for Culture media and Sport was unable to confirm funding arrangements.

TRANSPORT

Elephant & Castle ticket hall work progresses, link tunnel bids sought

Construction of the new ticket hall at Elephant & Castle Underground station in London has been completed to basement level five. Additionally, work on the ticket hall basement slab has begun.

The ticket hall is on course to be handed over to Transport for London (TfL) in early 2025. The station currently has separate entrances for the Bakerloo and Northern lines, which is inconvenient for passengers.

The new integrated ticket hall will fix this issue and increase the station’s capacity. It also requires passenger link tunnels to connect it to the existing Northern Line platforms. TfL started procuring a contractor to carry out this works in April and four suppliers have been invited to bid for the work.

MARINE

Welsh government plans partial infill of Swansea Dock channel

Swansea Council has received an application designed by Arcadis on behalf of the Welsh Government, for the partial infill of the Prince of Wales Dock channel. The scheme includes construction of a new public road, new private dock road, associated public realm and new culvert.

The proposal is to infill the channel entrance and construct a road to integrate the site with the surrounding area, providing a convenient east-west route across the dock.

The new public road will connect routes between the east and west of the dock. Water will be drawn from the channel to the required level for an edge protection to be installed and a foundation to be formed.

Bunds will be constructed to create an impound area with a geomembrane installed to seal the site.

BRIDGES

Musgrave infill reversed

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National Highways has completed the 13-week process to remove 1,000t of concrete infill from the Great Musgrave bridge in Cumbria. The roads body said the bridge will not need strengthening or weight restrictions before it reopens.

National Highways was ordered to remove the infill by Eden Valley Council after its retrospective planning application was rejected.

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