Mersey Gateway: connecting societies
The new Mersey Gateway bridge is accompanied by a new-look road system stretching nine kilometres of road improvements and new junctions connecting Runcorn to Widnes. The bridge is the centrepiece of the project, forming a landmark structure that will become an icon throughout the North-West and beyond. The design is based on a cable-stayed structure, similar to the Queensferry Crossing, with three slender towers rising from the estuary. The 80m high central tower stands shorter than the two outer towers, with the north tower standing 110m high and the south tower at 125m high. This unusual design was chosen to minimise the environmental impacts on the estuary. The bridge carries a highway made up of three lanes in each direction spanning 1km across the river. In total the crossing is 2.13km long including the approach viaducts on each side.
Reduced journey times, emissions, and cleaner air
Ramboll has played a significant role in the Mersey Gateway bridge, the spearhead of a 20-year regeneration project in the Halton region. Halton, which borders each side of the Mersey, is one of the smallest boroughs in the country, yet it has delivered one of the largest infrastructure projects in the country. The bridge provides a significant reduction in journey times, easing congestion for millions of people and reducing carbon emissions. The bridge will attract massive inward investment and regeneration in the region, with over 4,000 permanent direct and indirect jobs adding to Gross Value. Add to this cleaner air, the remediation of the contaminated land surrounding the crossing, improved pedestrian, cycling and public transport access to the existing Silver Jubilee Bridge, and it’s easy to see why the opening was so eagerly awaited.
Award winning remediation and feat of engineering project
Prior to starting the main works contract, Ramboll was responsible for managing several advance works contracts procured to mitigate programme risk, including advance diversions of statutory apparatus and an advance remediation contract.
Over the course of 13 months, we recovered almost 17 tonnes of chlorinated solvent contamination from beneath the ground.
The remediation project has attracted numerous awards, including the North West CIHT Best Practice Award, the Ground Engineering Sustainability Award and the CIHT Technological Application Award where judges commented, “We were impressed by the innovative remediation process, which recovered a substantial volume of technically challenging solvents, using in-situ technologies rather than bulk excavation…The project was delivered at a fixed cost, on time and within budget, with close stakeholder engagement being maintained at all times”.
The Mersey Gateway also picked up a special award from the ICE, that said "In recognition of ICE's bicentenary and a phenomenal feat of engineering which has changed the local skyline, the Mersey Gateway project is awarded the ICE 200 Special Award".
Ramboll continued its involvement on the scheme working under a new commission as part of a technical advisor team. This comprised CH2M Hill, Ramboll, IBI Group and Knight Architects, to support the Mersey Gateway Crossings Board with the technical and contractual administration of the project and to help it fulfil its contractual obligations. The team also provided technical staff for both the core (site based) and non-core (remote) elements of the team, ensuring the efficient construction of the bridge.
“Ramboll played a critical role in the project right from the very start, partnering us to secure funding, leading the remediation work and ensuring the designs and delivery met the very highest standards throughout. Quite simply the project wouldn’t have happened without their continuing support.”
Queensferry crossing: huge carbon saving
The Queensferry Crossing is the world’s longest three-tower, cable-stayed bridge. It is a vital strategic link for eastern Scotland, improving reliability for 24 million vehicle users per year. We identified significant cost and carbon savings, including avoidance of 7,000 tonnes of embodied carbon.