Thames Water is seeking suppliers to support a large-scale programme to map sewer networks across Greater London and the Thames Valley. The initiative is intended to reduce blockages, flooding, and pollution, and will contribute to the company’s Pollution Incident Reduction Plan (PIRP) during AMP8.
Unmapped sewers can cause delays in identifying and addressing issues such as blockages, internal and external flooding, and pollution incidents. By improving the accuracy and coverage of sewer maps, Thames Water aims to strengthen its response times and mitigate environmental impacts.
The procurement has been divided into three lots:
- Lot 1 – Aerial Mapping (£4,213,588 inc. VAT):
Survey of 2,484 km² across 71 Sewer Drainage Area Catchments (SDACs) using manned aircraft. Deliverables include georeferenced 2D, oblique 2D, and 3D imagery, with phased delivery by 2028. - Lot 2 – Asset Detection (£1,628,593 inc. VAT):
Identification of manholes, gullies, rainwater downpipes, soil stacks, misconnections, and outfalls, including confidence grading. - Lot 3 – Sewer Inferencing (£1,353,019 inc. VAT):
Semi-automated and automated inference of unmapped sewers, laterals, drains, rising mains, and selected sewage pumping stations, targeting at least 80% accuracy.
The contract is expected to run for an initial four-year term (March 2026 to February 2030), with options to extend for up to two additional years, potentially running to February 2032. Thames Water may also consider additional purchases of aerial survey services during the term.
One supplier will be appointed for each lot. While bidders can apply for multiple lots, Thames Water may limit awards to one lot per supplier to ensure resilience and risk distribution.
The deadline for requests to participate is 10:00 a.m. on 3 October 2025, with award decisions anticipated in February 2026. Interested suppliers are invited to register by providing company details and two nominated contacts. Successful applicants will then gain access to Thames Water’s Project SharePoint site, where the Procurement Specific Questionnaire (PSQ) and related documents are available. Further system access will be granted for suppliers who progress beyond the PSQ stage.
