We’re replacing damaged sea defences next to the historical Fort Cumberland site in Eastney, Portsmouth. The new sea defences will protect Fort Cumberland and three of our underground storm tanks, which are vital in helping to prevent flooding in the city. Large amounts of rock - around 9,500 tonnes - will be transported from Norway and positioned along the coastline to shore up the seawall. At high tide, the rock armour will be offloaded into the sea opposite the damaged section of the sea wall and will then be retrieved and brought to the beach at low tide using construction vehicles. The rock defences will be put into position along the damaged section of the sea wall. Before the works start, the existing broken sections of concrete sea defences will be crushed and removed.
When do the works start and finish?
We’re due to start in April 2017 and complete by October 2017, this is to avoid the wintering bird season
How much of the land does the sea defences protect?
The large rock sea defences will be placed along 115 metres of the beach.
Why are you doing this?
Our storm tanks store stormwater – wastewater heavily diluted with rainwater - during heavy rainfall. They play a vital role in protecting Portsmouth from flooding. Over time, the sea has eroded part of the wall of the structure which contains the tanks. If left much longer, our tanks could potentially be badly damaged and have a detrimental impact on the beach and bathing water . We invested £10 million in 2015 to improve the resilience of the tanks. We have a duty to ensure we carry out our daily operations in a way that protects our rivers, streams and coastal waters while also playing a key role in improving the health of our local environment.
How long will the beach area be closed off?
The small section of beach and grassland in Eastney, close to the small pier and our outfall pipe, will have to be closed for the duration of the works for health and safety reasons. We’re sorry about this but when it comes to the safety of the public, we can’t take any chances. We’d ask you to keep dogs on leads while walking near this area and adhere to the safety signs.
How many vehicles will be going to and from the site?
The rock will be delivered to the site by sea. Those living nearby may notice a small increase in vehicles around Fort Cumberland, especially at the start of the scheme and towards the end. However most vehicles will remain within the works site and beach area. A traffic management plan addresses the timing for vehicle movements, taking into consideration peak times, school hours and public hours.
What about noise?
We always try to minimise the impact of noise during any works. This scheme requires us to work to specific tide times, which means part of it will be carried out at sensitive hours of the day. The noise will be relatively short in duration when taken in the life of the works. Once the construction phase of the work is complete, any noise should be minimal. The crushing and removal of the existing damaged concrete defences will be limited to daylight hours only.
Can't they do the work at any other time?
We are governed by tide times, and for this scheme to go ahead, large rocks will need to be put into the ocean and collected during high tide. This is likely to be during the evening and early hours of the morning. We must also work to the environmental restrictions in place on our licence to carry out the scheme.
How much will this cost?
We’re investing £2.8 million.
Who is doing the works?
The works are being carried out by Galliford Try.
Have you told people about these works?
We have informed nearby residents, clubs and those who normally work in the area. We always engage with stakeholders and the local authority prior to any works of interest
Did you get planning permission?
We were granted planning permission for the works by Portsmouth City Council on 13 May 2016. A marine licence was obtained on 6 July and scheduled monument consent was obtained on 5 July 2016.
What about the environment?
The new sea defences will support the local environment infrastructure. The historically important Fort Cumberland which is popular with dog walkers and tourists lies just behind the site. We worked closely with environmental experts when planning the scheme and will remain in close liaison with them throughout.
Why are the rocks coming from Norway?
We're importing the large rocks from Norway because of their type, density and availability for this scheme.