KBS Maritime has reached a key milestone in the upgrade of D Lock at His Majesty’s Naval Base Portsmouth, with the successful Factory Acceptance Testing (FAT) of new penstocks.
This marks another important step in a wider programme of works across the waterfront, where we have already completed major enabling activities including large-scale silt removal, structural repairs and preparations for new systems.
Penstocks play a central role in operations, acting as large-scale gates that control the flow of water. This allows the dock to be safely flooded and drained, enabling ships to be transited through the Naval Base and supporting ongoing maintenance and operational activity.
Delivered in partnership with Glenfield Invicta, the programme will see a total of 24 penstocks replaced within the D Lock regeneration programme. With a value of just under £12m, the new penstocks bring together UK-based expertise and supply chain capability, with actuators manufactured in the UK and supporting steelwork and road covers produced by suppliers local to the Naval Base.
The programme began in November 2025 following detailed survey and design work, with procurement and manufacture progressing through late 2025 and early 2026. On-site activity started earlier this year, with decommissioning and removal of the existing penstocks at D Lock running from March through to July 2026. Installation of the new systems will then begin, continuing through to April 2027, before further phases extend the replacement programme at North Pumping Station and P120 through to 2028.
Once complete, the upgrades will replace ageing equipment, some of which has been in service for decades, with modern designs that improve durability and reduce maintenance requirements.
The successful completion of Factory Acceptance Testing provides confidence as the programme moves into its next phase of delivery.
