Scope
Reference
24/16/PS
Description
Tower Bridge Mud Tanks - this project will deliver repairs and enhancement works to 6no. mud tanks that form part of the rainwater/surface drainage infrastructure at Tower Bridge, as well as associated repair/enhancement works to improve safety, access, lighting, etc. in the 6no. mud tanks bays, which are situated on the lower levels of the bridge.
Tower Bridge is a bascule bridge and beneath the two towers are the pivot and drive shafts and hydraulic operating machinery. Beneath the main pivot shafts are 6no. mud tanks; 3no. on the north side and 3no. on the south. The tanks serve to collect rainwater, surface run-off, and debris from the bascule arms when raised, to prevent them entering the chambers below. Currently, they regularly block up and overflow, and must be manually monitored and emptied. A condition survey was undertaken in 2017 which identified that all the mud tanks are in poor condition with significant
corrosion identified, and without exception all require repair to some extent.
Each mud tank consists of a front and rear chamber. The rear chambers will be assessed and repaired in situ. The front chambers will be cut out and replaced with a new mild steel chamber with deeper profile, improving the water storing capacity and providing adequate spatial clearanceto moving parts of the bridge. Both chambers will be protected with new GRP lining. Discharge pipework will need alteration and reconnection to the revised tank chambers. Each mud tank will receive new GRP mesh deck hinged covers, to prevent larger debris/detritus entering the tanks/chambers and causing blockages, while still permitting water/runoff to reach the tanks.
Beneath each mud tank lies a platform of original timber planks spanning the bascule chamber. This platform is currently inaccessible due to structural degradation (rot) caused by water overflow from the tanks above. A specialist contractor will assess the strength and condition of the timber planks. If they are deemed sufficient for maintenance loads, the planks will be restored and reused,
while damaged/rotten planks and the timber kerb will be replaced.
Each mud tank bay will also receive new handrails/guardrails to promote safer access, improved LED lighting (mixture of replacement and new/additional), new small power provision, and corrosion treatment/repainting
Total value (estimated)
- £1,400,000 excluding VAT
- £1,680,000 including VAT
Below the relevant threshold
Contract dates (estimated)
- 11 July 2025 to 5 December 2025
- 4 months, 26 days
Main procurement category
Works
CPV classifications
- 45221100 - Construction work for bridges
Contract locations
- UKI - London
Engagement
Engagement deadline
25 February 2025
The engagement was carried out before this notice was published.
Engagement process description
As part of our early market engagement, we contacted seven potential suppliers by email on 18th February 2025. The communication included a document outlining the proposed scope of the requirement, the estimated contract value, required insurance levels, and the intended form of contract. Suppliers were given one week to respond with expressions of interest.
Of the seven suppliers contacted, three confirmed their interest in participating, two declined, and two did not respond.
The purpose of this engagement was to assess market interest and gather initial feedback on the proposed approach. From the responses received, suppliers indicated that the form of contract and the specified insurance levels were broadly appropriate and did not present barriers to participation.
Participation
Particular suitability
- Small and medium-sized enterprises (SME)
- Voluntary, community and social enterprises (VCSE)
Submission
Publication date of tender notice (estimated)
22 April 2025
Contracting authority
The Mayor and Commonalty and Citizens of the City of London
- Public Procurement Organisation Number: PYQD-1693-MYXR
PO Box 270
City of London
EC2P 2EJ
United Kingdom
Telephone: 020 7606 3030
Email: jemma.borland@cityoflondon.gov.uk
Website: https://www.cityoflondon.gov.uk
Region: UKI43 - Haringey and Islington
Organisation type: Public authority - sub-central government