Cockett Wick sea wall improvements, Essex, UK

NEC has been used to improve tidal flood protection to more than 3000 properties and businesses along the Essex coast, UK. The £12 million Cockett Wick sea wall improvements scheme near Clacton-on-Sea was completed on time and budget in August 2024 under an NEC4 Professional Service Contract (PSC) and NEC4 Engineering and Construction Contract (ECC) Option C (target cost with activity schedule).

England’s Environment Agency let the project to consultant Jacobs and contractor Bam Nuttall, the eastern region delivery partners on its NEC-based collaborative delivery framework. The framework, under which all eight delivery partners are retained on NEC4 Framework Contracts (FC), is delivering £5.2 billion of flood and coastal erosion risk management capital works from 2019 to 2027. Work started on the Cockett Wick site in June 2023 and was physically completed in July 2024. NEC project manager Arcadis was also engaged on an NEC4 PSC.

The works involved raising and strengthening the existing 330 m long sea wall in front of the early-nineteenth-century Jaywick Martello Tower and Martello Beach Holiday Park. Over 150 steel tubular piles were driven through the existing sea wall structure and a new reinforced concrete footpath and raised sea wall were then built on top. A total of 12,500 t of rock armour was also added to the toe of the wall’s existing seaward revetment.

The scheme is a key part of the Essex and South Suffolk shoreline management plan, which aims to sustain the viability of seaside towns and their communities. It has a design life of 100 years and allows for the wall to be raised again in 50 years’ time to account for sea-level rise and climate change. The project was shortlisted for the Environmental Project of the Year Award in the 2024 British Construction Industry Awards.

Collaborative working

Julie McNulty of the Environment Agency says in line with the NEC requirement to act in a ‘spirit of mutual trust and co-operation’ the project was a fantastic example of successful collaboration. "The team worked together to manage the project risks and proactively deal with issues. Challenges were resolved together quickly through the NEC early warning process, mitigating delays and increased costs."

She says there were regular and open communications throughout the project delivery, as required by NEC. "There was a one-team approach to sharing information. This behaviour helped the team to develop innovative approaches, carbon-saving ideas and captured lessons for the benefit of the project and future schemes. It has been a great project to work on."

Examples of sustainable design and construction included switching from continuous flight augur piles to recycled steel tubes, saving 120 lorry loads of excavated soil and the purchase of new piles. Delivering rock armour by six barges saved 700 lorry movements and 48 t of carbon dioxide, and using drones and satellite-guided excavators during rock placing avoided the health and safety risks of people needing to walk on the revetment works.

Robert Harvey of Bam Nuttall said, "We are delighted to have worked collaboratively with the Environment Agency and Jacobs on the Cockett Wick project, providing a successful flood defence scheme for the area, with sustainability, innovation and the local area at its core, benefiting generations to come."

Louise Oldfield-Trim of Jacobs said, "A key factor in the project’s success was the full commitment to collaboration by the entire team, including the Environment Agency, BAM and Jacobs. This essential cooperation throughout the design and construction stages ensured a smooth, cost-effective delivery."

Benefits of using NEC

• NEC requirement to act in a ‘spirit of mutual trust and co-operation’ encouraged the design and construction framework partners to work collaboratively.
• NEC early warning process ensured issues were dealt with proactively and quickly, mitigating delays and increased costs.
• NEC ensured there were regular and open communications, leading to a one-team approach to sharing information.