The historic town of Chepstow is situated on the river Wye, and is subject to frequent tidal flooding with event records dating back to 1883. The 3ha flood risk area includes 80 houses and small businesses.
Whilst the economic case for flood defence was clear, the environmental value of the valley raised challenges in implementing an appropriate scheme due to the following:
• The river corridor is designated for its landscape and ecological value.
• A public park and riverside walk offer amenities which would have been compromised using a traditional approach.
• The fabric of an historic bridge could have been affected.
• Striking views across the river could have been interrupted.
• Parking and traffic flow was also an important local issue.
Atkins provided an integrated team of engineers and landscape architects who were tasked with developing a combined technical and environmental solution. This team challenged traditionally accepted constraints, such as whether roads could be closed to improve the defence alignment. Innovative materials such as laminated glass were used to overcome problems.
The resulting scheme has fully met the technical requirements for flood defence. In addition, it has provided an enhanced and sustainable traffic-free riverside park area. The valley's aesthetic value and the historic bridge have been preserved in full. The public perception of the scheme is one of an environmental enhancement rather than an engineering necessity. Approaches developed for this project and the lessons learned can be applied to sensitive sites across the country. Such practice can deliver unobtrusive flood defence where previously this had not been thought possible.
The scheme was formally opened by Sue Essex AM, Minister for the Environment, who praised the innovative approach as providing the right solution for this sensitive problem.
The project was funded by the Environment Agency's Wye Local Flood Defence Committee, Monmouthshire County Council and the Welsh Assembly Government.
