Falmouth Sewer Improvement Scheme (Stormwater Overflow Improvements)
Falmouth, Cornwall · Phase 1 completed May 2026; Phase 2 design work starting June 2026 [South West Water] · Part of the wider £760 million Turning the Tide programme [South West Water]; £70 million total project cost between Falmouth and Sidmouth, with £25 million spent in the last two years (as of April 2023) [Falmouth Packet]
The judgement call
Account-gated at launchFocus on increasing temporary storage of wastewater to reduce pressure on the sewer system during heavy rainfall [South West Water] - Phased approach to improvements, with initial focus on Queen Mary Gardens and subsequent design work for wider catchment improvements [South West Water]
Key engineering challenges
Reducing storm overflows to protect water quality in local beaches and rivers [South West Water] - Managing sewer system struggles during heavy rainfall due to surface water, groundwater ingress, and increasing demand [South West Water] - Delivering improvements in phases while maintaining service [South West Water]
Project facts
- Client / owner
- South West Water
- Lead contractor
- —
- Lead designers
- —
- Project type
- upgrade
- Scale
- New underground stormwater storage tank with a capacity of 302,000 litres beneath Gyllyngvase car park [South West Water]
- Disciplines
- Civil; environmental; hydraulic
- Standards & frameworks
- Environmental regulations for water quality; Turning the Tide programme
Sources: South West Water: https://www.southwestwater.co.uk/about-us/what-we-do/engineering-projects/wastewater/falmouth-stormwater-overflow-improvements (Accessed: 2026-06-10) - Falmouth Packet: https://www.falmouthpacket.co.uk/news/23439407.river-fal-sewage-treatment-upgrade-improve-water-quality/ (Accessed: 2026-06-10)