AquaticEngineering

Working Above Water, On Water & Under Water

Case Study : Pont Briwet Viaduct Replacement

AquaticEngineering is the UK’s largest fabricator of silt curtains for inland waterway application

Client: Network Rail & Council Main Contractor: Hochtief Contractor: AquaticEngineering Duration: 2013 – 2014 Value: £20,000,000

Pont Briwet was built in 1860 and is a Grade II listed wooden viaduct. The structure carries a single track rail line and a single lane toll road over the river between & railway station. The current speed limit for rail traffic is 20mph and there is a 2-tonne weight limit for highway traffic. The imposed weight limit on the existing rail and road bridges, as well as the narrow width of the road, currently restricts the level of road traffic permitted to use the bridge.

Over the years Pont Briwet has been partly reconstructed and repaired, however, it is now near the end of its life and is becoming uneconomical to repair.

Following an independent investigation by specialist engineers, a decision was taken to permanently close the 154 year old Pont Briwet Bridge over Afon Dwyryd on safety grounds.

Specialist Silt Curtain Fabricators AquaticEngineering were commissioned to design, supply & install a 650 x 5m silt curtain suitable to wrap around the project & protect the Adjacent SSSI

There were no working footprint issues on this wonderful site joining the silt curtains!

The silt curtain was of a design unique to AquaticEngineering which allowed for tidal variations

Work on the construction of the replacement road and Rail Bridge got underway

Tens of thousands of tonnes of rock backfill were required to create the working/access platform The silt curtain enveloped this zone to protect the estuary.

Silt curtains can cope with extreme conditions – and this was a tough project

The river used to be here!

And here!

The scheme aims to create a robust inter-modal transport link, easing road congestion and significantly improving the reliability of rail services. As part of the proposed work, a new bridge will be installed to accommodate a dual carriageway; renewed railway track; cycle path and footpath

Benefits of the proposed scheme will be:

 Free transport links as toll charges will be waived by Network Rail  Less road congestion with a two way carriageway  Better transport links for heavier vehicles, i.e. ambulances, coaches or lorries, which now detour 8 miles through the village of  More alternative transport options for the community and tourists with a new cycle path and footpath that link with the National Coastal Path and Welsh National Cycle Route 8  A better performing railway as the renewed track will provide an increased line speed of 40mph  A more reliable and robust transport link on a new structure that will be less prone to flooding and designed to last for at least another century

1st November 2014 – so far so good!

All curtains are manufactured entirely by AquaticEngineering on the Isle of Wight

24hr 365 day Emergency Fabrication & Nationwide Installation Service

100% satisfaction service – we will attend site at short notice if the curtain is compromised in any way by boat traffic or any other unforeseen occurrence to promptly rectify the situation.

AquaticEngineering - Working Above Water, On Water & Under Water

Kingarth Lodge, Church Road, Binstead, Isle of Wight PO33 3SZ www.aquaticengineering.co.uk

Tel No 1: 01983 616668 Mob No: 07891 438666 [email protected]

The AquaticGroup : AquaticEngineering : SiltCurtainsUK : AquaticConsultancy