Portsmouth City Council has appointed Knights Brown to carry out the fifth and final phase of the North Portsea Coastal Scheme, starting in September. Knights Brown previously constructed the first and third phases, meaning they have carried out the majority of works on this valuable scheme.
The scheme as a whole is one of the largest local authority-led coastal flood defence projects in the UK and is crucial for the protection of Portsmouth residents. The defences will safeguard more than 4,000 homes and almost 500 businesses. In total, it covers 8.4km of coastline from Tipner through to Milton. Most of the area is low-lying and many of the current coastal defences were approaching the end of their effective lives.
The final phase of works will take place along Ports Creek in North Portsea and will include 1.9 km of flood defences. The design consists of a sloped earth embankment, which provides the required flood defence level, with a rock armour toe. Rock armour dissipates wave energy, therefore preventing further breakup of the shoreline.
This latest phase will be carried out in an area famous for its green open spaces so the focus will be on retaining the natural feel by planting trees, native scrub and wildflower, improving paths, and access to the coastal path along the waterfront.
New seating, play and viewing areas along the coastal path route will create a more enjoyable environment for visitors spending their time here, as well as people walking. Information boards will be added and updated along the path to tie in with the upgraded signs from the previous phases, focussing on the history and environment of the area.
The North Portsea shoreline carries several important environmental designations due to the unique habitat. To protect and encourage local wildlife a range of nest boxes suitable for breeding birds will be put up before clearance activities start. New bat boxes will be positioned in the woodland areas to increase roosting potential and kingfishers will benefit from tunnels which will be added as an additional area for nesting.
Work is being carried out in collaboration with an on-site archaeologist and Historic England as the work area is next to the Hilsea Lines which are a line of 18th and 19th century fortifications built to protect the northern approach to Portsea Island. They formed an important part of Portsmouth’s defences and are the best surviving example of a bastioned and casemated defensive line built in England and are a Scheduled Ancient Monument.
The North Portsea Coastal Scheme will protect the Hilsea Lines by providing a future proof flood defence system, ensuring that this nationally important historical asset will be available for visitors to enjoy for the decades ahead.
The project is funded by the Environment Agency and implemented by Coastal Partners on behalf of Portsmouth City Council.
Mike Crook, Divisional Director, Knights Brown comments:
“We are delighted to be appointed as the principal contractor to carry out the fifth and final phase of the North Portsea Coastal scheme. The third award, of the five part scheme, demonstrates our capability and trusted collaborative relationship with Coastal Partners.
Our extensive expertise in coastal civil engineering, and our local knowledge, will enable us to deliver this essential flood defence scheme, which will safeguard residents and businesses for the next 100 years. All of the improvements will be delivered with the highest standard in order to foster the growth of local marine life and enhance the social space for the local community.”
Cllr Steve Pitt, Portsmouth City Council Leader comments:
“We’re very pleased to be working collaboratively with Knights Brown on the final phase of the North Portsea Coastal Scheme. It’s an exciting time as we forge towards completing the final link in this vital £85.9million sea defence project, which is made possible thanks to funding by the Environment Agency.”
