Walnut Tree Viaduct
Walnut Tree Viaduct | |
---|---|
British Railways Cardiff Council | |
Preceded by | Walnut Tree Tunnel 490 yards (450 m) |
Followed by | Penrhos Lower Junction |
Characteristics | |
Material | Brick columns Steel lattice girders spans |
Total length | 1,548 feet (472 m) |
Height | 120 feet (37 m) |
No. of spans | 7 |
History | |
Architect | Sir James Szlumper |
Designer | Sir James Szlumper |
Engineering design by | Sir James Szlumper |
Construction start | 1901 |
Construction end | 1901 |
Closed | 1969 |
Location | |
Walnut Tree Viaduct was a
Background
During the Industrial Revolution, and the mass-extraction of coal from South Wales, there was a resultant growth in construction of railways into the South Wales Coalfield. The Taff Vale Railway so monopolised the trade of shipping coal to Cardiff Docks, that mine owners were desperate for competitor railway companies to both improve speeds of shipping, provide access to new markets, and hence reduce shipping rates.
The first section of the
However, by 1880 the TVR and RVR were so congested with coal traffic, that a group of coal mine owners, iron makers and industrialists led by David Davies of Ocean Collieries, had all suffered from the capacity and monopoly issues created by two companies:
- Taff Vale Railway: which provided the dominant rail infrastructure. Capacity issues were particularly dominant after Pontypridd railway station, where down loaded trains and up return empty wagons were restricted to a single double track route, which could not be expanded due to the geographic challenges of the valley.
- Lord Bute, were sufficient to serve his coal-exporting needs, but did not have sufficient capacity to cope with new mine developments.
In light of the geographic restrictions of the valley south of Pontypridd, Davies proposed development of a secondary route which terminated at
The Barry Dock and Railway Bill was introduced in the 1883 Parliamentary session but was defeated by opposition, particularly from the Bute Docks and Taff Vale Railway.
Llanbradach branch
By 1889 the main line of the BRC connected
Having already engineered the main line of the BRC, Chief Engineer
After passing through the Lesser Garth hill via the Walnut Tree Tunnel (490 yards (450 m)), a siding served Dolomite Quarry, before the line curved right to reach the viaduct which bridged the River Taff valley via the congested geographical squeeze-point just north of Radyr, known as Walnut Tree. The height and form of the viaduct at this point not only needed to cope with the congested valley bottom, crossing the River Taff, but also at its north-eastern end, curve onto a shelf of rock on the eastern hillside followed by a deep cutting for ¼ mile. The railway then climbed the eastern hillside to finally route north-east to reach the Rhymney Railway via Penrhos Lower Junction, allowing access to Caerphilly.
The BRC Llanbradach extension continued along the eastern side of the Taff valley, to then span the RR and the TVR via the
The line from Tynycaeau Junction to Penrhos Junction was officially named the Penrhos Branch by the GWR and Successor BR Western Region and given the Engineer's Line reference PRS. The former Barry Railway's Cadoxton-Trehafod main line was given the ELR, CTD. These abbreviations still hold for remaining structures and land remaining from BR days and now in the care of the Historic Railways Estate/Highways England.
Construction
Facing similar problems to those that Chief Engineer
- That the necessary height, created both a structural problem and a wind problem, as the valley funnelled and hence increased wind speed.
- That a lack of suitable local resources meant that shipping in materials was the only option.
- That a stone structure would result in an unstable and high-maintenance bridge, the thick structure of which would create additional compressed wind flow around the rail tracks, resulting in a possible safety hazard for passengers and train crew.
His recommendation therefore like Liddell to the board of the BRC was for steel lattice girders spans, set atop brick-built supporting columns. The final structure, which took less than 12 months to build, opened in 1901.[2] At its maximum 120 feet (37 m) high, the seven spans created a structure of 1,548 feet (472 m) long, which curved slightly at its western end to enable the line to bend onto the rock shelf.[3]
Closure and demolition
The Llanbradach branch (or B&M Extension) enjoyed a short but productive life north of Penrhos Lower Junction as it was de-commissioned by the later owning
Later renamed the 'Penrhos Branch' by the GWR, post-nationalisation it came under the control of
After
Today
Only the Walnut Tree tunnel abutment, an angled pillar and Taff Bank pier remain, all visible from the village and the A470. The Taff Bank pier was used in 1977 for displaying a message commemorating the Silver Jubilee of Elizabeth II, with the wording still visible today. Parts of the remaining track bed are now incorporated into the Taff Trail.[8]
References
- ^ Watson, Richard. "The Birth of Barry – When Coal was King 2". Legacies - South East Wales. BBC. Retrieved 12 January 2009.
- ^ The Courtney Haydon Collection. "Walnut Tree Viaduct". THE RAILWAY CORRESPONDENCE AND TRAVEL SOCIETY. Retrieved 28 December 2012.
- ^ a b c "Taffs Well". Rhondda-Cynon-Taf.gov.uk. Retrieved 28 December 2012.
- ^ a b "Walnut Tree Tunnel". forgottenrelics.co.uk. Retrieved 28 December 2012.
- ^ "Penrhos Branch". trackbed.com. Retrieved 28 December 2012.
- ^ a b John Wiltshire (29 September 1969). "Demolition of Walnut Tree Viaduct". John Wiltshire. Retrieved 28 December 2012.
- ^ "Walnut Tree Viaduct". wikimapia.org. Retrieved 28 December 2012.
- ^ "Llanbradach Viaduct". Caerphilly.gov.uk. Retrieved 28 December 2012.