Cardiff

Cardiff

Cardiff Wastewater Treatment Works, the largest facility run by Welsh Water (Dŵr Cymru), serves around 800,000 people in the capital. As part of a major upgrade, Welsh Water chose Cambi’s thermal hydrolysis process (THP) to convert the site into a modern sludge treatment centre within existing boundaries.

The compact THP technology, ideal for the site’s biological sludge, delivered significant benefits: reduced drying costs, boosted biogas production for internal use, and a 35,000-tonne annual cut in CO₂ emissions. The resulting pathogen-free sludge cake is now used as fertiliser across South Wales.

Cardiff is one of a handful of Welsh Water facilities using THP and driving progress towards the utility's goal of a net-zero 2040.