To comply with the Freshwater Fisheries Directive (FFD) the ammonia discharge levels at the Castleford Water Treatment Works had to be reduced from 40 milligrams/litre (mg/l) to 10mg/l by 31 September 2014.
To achieve this, the works were in need of modernisation and upgrading to increase its current treatment capacity and improve its discharge quality.
£16m of investment was allocated for the improvements to enable the works to serve a 2025 population equivalent of approximately 57,082; which is a 21.5% increase from present figures.
As a result of the growth in population, a further compliance date of 31 March 2015 was applied to the scheme.
IWS was selected as MGJV’s mechanical contractor for the project.
The works comprised the following activities:
- New Inlet pumping stations
- New Inlet works with inclined fine screens, screenings handling and grit removal
- 3 No new primary settlement tanks with half-bridge scrapers
- New Activated Sludge Plant complete with aeration system and external anoxic zone complete with mixers
- 3 No. new final settlement tanks with half-bridge scrapers
- New sludge storage tanks with mixing systems, dewatering centrifuges, conveyors and polymer dosing systems
The Mechanical Installation Package comprised of the design, supply and installation of the following:
- ASP area pipework and valves
- Liquor returns pumping station and valves
- RAS / SAS pumping station and valves
- Sludge holding tanks pipework and valves
- Centrifuge feed pumps, pipework and valves
- FST de-sludge chamber actuated bellmouths pipework and valves
The scope of works also comprised:
- Supply and install of drain valve connections in de-sludge chambers x 3 OFF
- Install F-I DN400 flow meters in de-sludge chambers x 2 OFF
The Castleford project exemplifies open, honest and collaborative working between all parties to ensure the project’s vision and strategy was met. The strong team ethos of working collaboratively has driven innovative solutions, creating significant cost savings over the project as a whole which has enabled reinvestment back into the client business to address other needs.