Scope
Reference
Open Raft Facility
Description
The open raft facility is a floating structure for testing of underwater ultrasonic devices located on the Wraysbury Reservoir in Middlesex, UK. It comprises a buoyant structure assembled from modular pontoons with a steel grillage deck structure sheathed with non-slip GRP panels. There are two large moonpools with gantry cranes over each, plus four hydraulic knuckle boom cranes for handling test equipment and loading/off-loading from supply boats. Accommodation comprises modular buildings fitted out as laboratory, office, accommodation, workshop and store spaces.
The whole structure is to be modular, delivered to site by road and assembled in the water.
Mooring is to four concrete sinkers with mooring wires and shock absorbing chains to the
pontoon.Included in the contract is the safe and ecologically compliant disposal of the existing facility.
The objective of the project is to replace the existing facility with a new and substantially
improved pontoon for the testing and calibration of underwater acoustic transducers and
associated apparatus.
Overall dimensions of the pontoon are approximately 32.50 metres long and 31 metres beam comprising five hulls each consisting of six (6) modular pontoons supporting a deck of steel grillage construction topped with non-slip glass fibre panels. Safety railings, arranged in portable sections are to be fitted around the perimeter of the pontoon and around both moon pools.
Within the pontoon will be two (2) moon pools one about 20.00 metres long, the other around 15 metres, both are 4.20 metres wide over which will be gantry cranes incorporating the test equipment lifting stations.
For loading/offloading equipment, stores and ancillary items there will be four (4) hydraulic
knuckle boom cranes.
Accommodation comprises four (4) structures constructed from modular buildings; the main two storey accommodation building, located on the centreline between the moon pools, towards the forward end of the pontoon, incorporating; on the ground floor, the laboratories, workshop, store and plant room.
On the first floor, accessed by an internal staircase, will be a canteen with kitchenette and an open plan office.
Aft of the main building towards the stern is a single storey building, described as the client store/office space; it is divided into two sections, one for the storage of test equipment and the other office spaces for clients.
To starboard forward is a small single storey building for additional office space; aft to port is another small building for use as a garage/store.
Suitable rubber 'D' section fendering is to be fitted around the periphery of the pontoon to prevent damage of both the pontoon and the vessels servicing it.
Services are arranged from shore to the pontoon and include 400/3/50 AC power supply,
telephone and internet.
Mooring of the pontoon will be by four (4) concrete sinkers suitably positioned on the reservoir bottom and connected to the pontoon by adjustable length steel galvanised wire mooring warps with heavy short link chain cable shock absorbers.
Budgeted amount: £3,750,000.00
Total value (estimated)
- £3,750,000 excluding VAT
- £4,500,000 including VAT
Contract dates (estimated)
- 28 November 2025 to 30 November 2026
- 1 year, 3 days
Main category
Works
CPV classifications
- 44000000 - Construction structures and materials; auxiliary products to construction (except electric apparatus)
- 45000000 - Construction work
- 71000000 - Architectural, construction, engineering and inspection services
Contract locations
- UKC - North East (England)
- UKD - North West (England)
- UKE - Yorkshire and the Humber
- UKF - East Midlands (England)
- UKG - West Midlands (England)
- UKH - East of England
- UKI - London
- UKJ - South East (England)
- UKK - South West (England)
Participation
Particular suitability
Small and medium-sized enterprises (SME)
Submission
Publication date of tender notice (estimated)
30 June 2025
Procedure
Procedure type
Open procedure
Above or below total value threshold
Above or equal to threshold
Contracting authority
NPL Management Limited
- Companies House: 02937881
- Public Procurement Organisation Number: PYDB-8862-JBYM
National Physical Laboratory
Teddington
TW11 0LW
United Kingdom
Email: procurement@npl.co.uk
Website: http://www.npl.co.uk
Region: UKI75 - Hounslow and Richmond upon Thames
Organisation type: Public undertaking (commercial organisation subject to public authority oversight)