Wastewater Treatment


CAW has been providing services for the operation and maintenance of wastewater treatment plant since 1999 and currently manages the operation and maintenance of wastewater treatment plants with a combined capacity of 2 million PE.

Delivery of Service

The provision of wastewater treatment services is carried out by a dedicated team of over 60 highly trained professionals and technicians under the management of the CAW’s Operations Director. Collectively the Wastewater Treatment Operations Team possess an extensive knowledge and capability in the operation and optimisation of both conventional and advanced wastewater  treatment technologies, including preliminary treatment, primary sedimentation, lamella settlement, activated sludge processes, sequence batch reactor processes, final settlement and UV disinfection.  The Team also operates and maintains a number of advanced sludge treatment facilities incorporating a range of technologies including thermal hydrolysis, anaerobic digestion, sludge dewatering and drying and energy recovery.

CAW provides a full 24/7 Operation & Maintenance Service for wastewater treatment with the capability to monitor wastewater treatment plants remotely through automated telemetry SCADA systems On-site laboratory and processing optimisation testing can also be provided as well as full access to independent accredited laboratory testing services.


In providing operation and maintenance services for wastewater treatment plants, CAW is committed to maximising the recovery of resources within the waste streams. The sludge treatment processes managed and operated by CAW generate approximately 25,000 tonnes of nutrient rich fertiliser annually which is recycled to agricultural lands as well as generating over 14,000,000m3 of renewable bio-gas annually, equivalent to 85,000 MWh of energy.

Quality Assurance

The wastewater treatment services provided by CAW are delivered through CAW’s Integrated Management System (IMS) which is based on the accredited ISO 9001: Quality Management System Standard; the accredited ISO 14001: Environmental Management System Standard; the accredited OHSAS 18001: Safety Management System Standard and the accredited ISO 50001: Energy Management Standard.

Delivery of Capital Projects

In addition, CAW’s experience in water treatment is not just confined to operation and maintenance. CAW also provide design and build capability for the delivery of wastewater treatment plants. Since 2005 CAW has delivered over €50m of wastewater treatment capital works on a design and build basis, the most significant project being the expansion of the Sludge Treatment facility at the Ringsend WwTW at a capital cost of €18.9m.