Thames Water has awarded an AMP8 contract for a major upgrade at its Maple Lodge Sewage Treatment Works with a current estimated value between £140 million to £280 million (inc VAT).

Photo credit Mark Percy: Thames Water Maple Lodge STW
Scope of the wide-ranging project project includes the following packages of work:
- An additional inlet screen with civils alterations and screening handling upgrade
- An additional detritor and flow inlet channel, incorporating a new storm separation weir
- A new storm tank and river outfall, including flow transfer culvert and new storm return pumping station
- Upgrades to the existing six PSTs and conversion of three storm tanks into PSTs, fitted with chain and flight scraper Replacement Primary chemical dosing pumps to aid Phosphorus removal
- A new activated sludge plant Bank C, with new feed PS and blowers
- Eight new 28m diameter final settlement tanks, interconnecting pipework, distribution chambers and RAS system
- A new secondary chemical dosing system to aid Phosphorus removal
- Two new Tertiary Solids Removal treatment plants, one serving the effluent from Bank A and B, and one serving the effluent from the new Bank C
- An additional Drum thickener
- New incoming switchboard for the new DNO supply
- Modification and upgrade of HV/LV networks
- Modification and upgrade to the power management system and site-wide SCADA
- Modification and upgrade to the Process SCADA
- Additional standby powered generation
- Demolition and removal of redundant structures, plant and equipment
Kier Infrastructure has been awarded the contract – the standstill period will run until 26 February 2026 and the earliest date the contract will be signed is 31 March 2026.
Current estimated start and end contract dates are 1 April 2026 to 29 March 2030.
HUBER Technology UK & Ireland are inviting people to register for their March webinar where they will be providing information about HUBER water intake screens for municipal and industrial applications.

Hear how United Utilities is accelerating its investment to reduce spills from storm overflows across the Northwest.