KierBAM wins c.£600m 10 Dock contract as Devonport submarine dock enters main construction

Babcock International Group has awarded the KierBAM joint venture a contract worth about £600m to build the water-retaining boundary and associated infrastructure for 10 Dock at Devonport in Plymouth, the company said.

Babcock said the Ministry of Defence (MOD)-funded award moves the redevelopment of the dock into its main construction phase and builds on the completion of enabling works. Kier, in its own release, described the appointment as supporting the delivery of a £600m programme of works on 10 Dock, made on behalf of the MOD's Defence Nuclear Enterprise (DNE).

Phil Brown, Managing Director for Major Nuclear Capital Programmes at Babcock, said: "This contract award marks a major milestone for the 10 Dock programme and the beginning of the next phase of delivery."

Babcock expects the wider 10 Dock programme to support about 1,500 jobs across the supply chain, including about 300 Babcock roles at Devonport.

The works

According to Kier, the scope covers a water-retaining boundary structure and nuclear licensed components. The civil engineering includes buttresses, new subways and in-situ subway structures, together with rock anchors, dowels, reinforcement and a multi-tonne caisson.

The award follows an early contractor involvement phase during which the joint venture commissioned a concrete batching plant and set up site logistics, welfare and office accommodation, Kier said.

Babcock is delivering the 10 Dock main works through its Major Nuclear Capital Programmes business unit at Devonport. Kier said KBJV works within Babcock's Integrated Major Infrastructure Projects team at the site.

Rear Admiral Martyn Boyes, Director Submarine Support at the DNE, said: "This milestone at 10 Dock demonstrates the strong progress we are making with our industry partners and wider supply chain, underpinned by substantial MOD investment across the enterprise".

Neither release gives a construction programme or completion date for the KierBAM works.

How the contract came about

The joint venture's involvement at 10 Dock dates from July 2022, when BAM announced that KBJV had been competitively awarded an NEC4 framework contract for the Main Works Civils scope on the project. BAM said the framework was structured to allow multiple call-off contracts, and that the project included redeveloping a dry dock for nuclear submarines, with a scope covering mechanical, electrical, instrumentation, control and automation technology for the new dock building.

Demolition of office blocks around 10 Dock started in May 2022 as the first stage of the Devonport regeneration, according to Babcock. At that point the MOD had awarded Babcock initial contracts worth about £140m for infrastructure design and enabling works since 2020. Babcock said the dock had previously been used for Landing Craft platform maintenance.

In November 2023 Babcock signed a four-year, £750m contract with the MOD's Submarine Delivery Agency for submarine support infrastructure at Devonport, covering a dock, logistics and modern support facilities. Babcock said at the time that the programme would see a further 1,000 construction roles created.

Wider MOD investment

The MOD confirmed in July 2026 that it is investing £26bn over ten years to modernise HMNB Clyde, HMNB Devonport and HMNB Portsmouth, funding set out in the Defence Investment Plan. Luke Pollard MP, Minister for Defence Readiness and Industry, described it as the largest investment in the naval bases since the Cold War.

Within that, the MOD cites a £4.4bn investment over ten years in HMNB Devonport and Devonport Royal Dockyard. It describes the co-located Royal Navy and Babcock site as providing deep submarine maintenance with about 8,000 personnel.

The MOD says the DNE supports more than 47,000 jobs across the UK and spent more than £9bn directly with industry partners in the 2024/25 financial year.

The joint venture

Kier said KBJV's appointment builds on its involvement in the nuclear and defence sectors, including civil engineering works at Hinkley Point C, where Kier says the joint venture has been on site since 2012, and ongoing works across Devonport Royal Dockyard.

Ian Hubbard, Managing Director of Social Infrastructure, Nuclear and Defence at BAM UK and Ireland, said the joint venture's ongoing work at Devonport serves the evolving requirements of the Royal Navy and helps maintain the availability of its current and future fleet.

Devonport Royal Dockyard was established in 1691 and is co-located with HMNB Devonport, which Kier describes as the largest naval base in Western Europe.