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Defence & spaceNaval Base Infrastructure, Submarine Refit, Modernization

Devonport Naval Base Submarine Refit Facilities (Submarine Waterfront Infrastructure - SWIF)

HMNB Devonport, Plymouth, UK · 2024–Ongoing (SWIF project underway, with milestones in 2025) · £750m (Submarine Waterfront Infrastructure - SWIF project), £560m (Deep Maintenance Period for a single submarine)

The judgement call

Account-gated at launch

The SWIF project is a critical investment to restore and modernize the UK's submarine maintenance capabilities, ensuring the long-term support of the nuclear deterrent. - The significant investment highlights the strategic importance of Devonport as the primary refit base for the Royal Navy's submarine fleet. - The Deep Maintenance Period for submarines involves extensive overhauls, demonstrating the scale and complexity of the engineering work undertaken. - The project emphasizes the need for continuous infrastructure upgrades to keep pace with evolving naval technology and operational requirements.

Key engineering challenges

Modernizing and expanding existing dry docks and waterfront infrastructure to support the current and future submarine fleet. - Managing the complexities of working with nuclear-powered submarines, requiring stringent safety and environmental protocols. - Ensuring facilities can accommodate the increasing size and technological complexity of modern submarines. - Delivering projects within an operational naval base, minimizing disruption to ongoing refit and maintenance schedules.

Project facts

Client / owner
Royal Navy, Ministry of Defence
Lead contractor
Lead designers
Project type
upgrade | refurbishment | new build
Scale
Modernization of facilities for nuclear-powered attack submarines; Deep Maintenance Period for submarines.
Disciplines
Civil; Structural; Marine; Nuclear Engineering; Systems Engineering; Defence Engineering
Standards & frameworks
Ministry of Defence (MOD) standards, nuclear safety regulations, naval engineering standards, UK construction and safety regulations.

Sources: Royal Navy: Victorious milestone as submarine enters Devonport dock in £560M... (https://www.royalnavy.mod.uk/news/2025/may/23/20250523-victorious-milestone-as-submarine-enters-devonport) - Navy Lookout: The future of surface ship support at Devonport Dockyard (https://www.navylookout.com/the-future-of-surface-ship-support-at-devonport-dockyard/) - Nuclear Information Service: Devonport-briefing.pdf (https://www.nuclearinfo.org/wp-content/uploads/2024/01/Devonport-briefing.pdf) - NAVSEA: Royal Navy's nuclear submarine support facility upgraded (https://www.youtube.com/watch?v=PjzzFB_9K90) - Wikipedia: HMNB Devonport (https://en.wikipedia.org/wiki/HMNB_Devonport)