Source: https://tendernation.io/opportunities/01a13cda-d06c-72cf-afd4-5359a201c710/wat0042-04-1-basin-caisson-cofferdam-masonry-repairs-installation closed GB restricted procedure # WAT0042-04 - 1 Basin Caisson - Cofferdam, Masonry Repairs, Installation [Ministry of Defence](https://tendernation.io/buyers/ministry-of-defence) Estimated value £3,000,000 Published 25 Jun 2024 Deadline Closed 28 Jun 2024 ## About this tender The Tenderer should be aware that the works detailed in this package are constrained due to the nature of the location they are to be conducted in. ### Project location ### HM Naval Base Portsmouth The Contractor shall be expected to adhere by the HMNB site security requirements, all Contractors and Sub-Contractors shall be BPSS security vetted and will be required to hold the relevant site security passes. The Contractor shall be expected to hold the following levels of insurance £10m Public Liability, £10m Product Liability, £5m Professional Indemnity. ### KBS Maritime - Introduction KBS Maritime is a joint venture between KBR and BAE Systems, bringing together two global players with a rich heritage of delivering excellence, innovation and reliability. The joint venture will combine the expertise of KBR as a global leader in infrastructure asset management and services with BAE Systems' experience and capability within Portsmouth Naval Base. KBS Maritime are delivering an ambitious, modern and enduring change to the Portsmouth Naval base infrastructure, securing investment in the local community and ensuring fit-for-purpose, world-leading fleet support for the Royal Navy and the UK in the decades ahead. ### Project Background Proposed to replace the existing caisson to 1 Basin. Proposed works to be undertaken as per the design and surveys approved with Historic England and Crown Estates. Install perimeter CPNI fencing to secure the site for the duration of the project. Installation of temporary cofferdams to the East and West that will not impact the historic fabric. Dewater and inspect and survey the 1 Basin stonework. Monitor historic seawalls and ground water levels during the works. Undertake stone wall repairs in accordance with Historic England detail specification and approval. Replace the penstock gate with electric operated replacement with civil works and electrical supply required to operate. Demolition and removal of the existing caisson constructure to 1 Basin. Repairs to the caisson groove and prepare for replacement caisson arrival (by others) removal all structural supports. Remove and survey the condition of the road bridge. Repair works to the sill and stone repairs to match the existing structure to the detailed specifications to Historic England specification. Install a temporary foot bridge during the project. Refurbishment and load testing of fairleads and bollards and leave in full working order for ongoing operations. Clean, survey and remedial repairs to historic brickwork culvert after dewatering. Remove the temporary cofferdams and refit road bridge after caisson has been replaced and all works to the bridge has been completed. Additional information: If you are interested in this opportunity, please express an interest through KBS' tendering portal to access the Selection Questionnaire and NDA; [uk.eu-supply.com](https://uk.eu-supply.com/ctm/supplier/publictenders?B=KBS) Send form to: Read full description ## CPV classification Marine construction works Source Contracts Finder (UK) [View official notice](https://www.contractsfinder.service.gov.uk/notice/3002c4f1-0c30-4f8b-9bed-0692c7e53645) Never miss a tender like this again Get AI summaries, deadline alerts and a bid pipeline for tenders matched to your business. Free to start. 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