Civil engineering and infrastructure company Barhale is to undertake microtunnelling on a stormwater management scheme on the Essex coast.
Anglian Water’s £18m investment in stormwater infrastructure at Walton-on-the-Naze is designed to provide additional protection to the Essex coast in the event of severe weather conditions.
The scheme is part of Anglian Water’s ongoing programme to improve resilience within its network and involves the construction of a new 5,000m³ storm tank and associated tunnelling works adjacent to the existing Walton-on-the-Naze terminal pumping station.
Work will be delivered through Anglian Water’s @one Alliance, the strategic delivery vehicle for Anglian Water’s Integrated Main Works programme. Barhale will be principal contractor for the scheme.
The new storm tank will feature an innovative “pill shaped” design to avoid the course of an existing aquifer and sewer. It will be built using a diaphragm wall, with excavation carried out from within.
It will be connected to an existing storm tank through a new 84m-long, 1200mm pipeline that will be constructed using concrete jacking pipes through microtunnelling.
Barhale project manager Dan Ledger said investigations and tracer studies by the Environment Agency and Anglian Water identified the need for additional storage.
“The upgrades will provide a major boost to site storage capacity, helping to protect the environment and bathing water quality,” he said.
He added that the site, particularly the presence of the aquifer, had presented some interesting design challenges and construction constraints.
“We have responded by developing the innovative tank design and by using a diaphragm wall construction which will minimise the size of the excavation area,” said Ledger.
Work is scheduled to start soon and be completed in November 2027.
Anglian Water’s @one Alliance has eight partner organisations: Anglian Water, Balfour Beatty, Barhale, Binnies, Mott MacDonald Bentley, MWH Treatment, Skanska and Sweco.
