Cardigan’s highly controversial Wastewater Treatment Works is to be fully replaced as part of a £20m investment programme carried out by Welsh Water.

The announcement was made on Thursday (October 12), with assurances from the water company that the long-overdue project will ‘improve river water quality in the Teifi and help protect the wider environment’.

“We’ve been working hard in recent years to tackle these challenges at Cardigan wastewater treatment works which has involved undertaking lengthy and complex investigations,” said Welsh Water’s Managing Director of Wastewater Services, Steve Wilson.

“Having considered how other companies and countries are tackling seawater intrusion into treatment works, which is becoming more common as sea levels rise due to climate change, we have identified that the only sustainable solution involves investing £20 million to replace Cardigan wastewater treatment works.”

Welsh Water’s investigations have confirmed that seawater enters the site from the tidal river, especially during spring high tides.

This process, known as saline intrusion, affects the treatment process at the site and can result in Cardigan site not having the capacity needed to deal with wastewater entering the works This can cause local storm overflows to discharge more than they should into the local estuary.  However Welsh Water states that bathing waters in the area (Poppit Sands) continue to meet “excellent” water quality standard as monitored by Natural Resources Wales.

Attempts by Welsh Water, working in conjunction with Natural Resources Wales and international specialist contractors, to remove the seawater from the system have had limited success.

But now, after carrying out extensive trials and installing two pilot treatment plants at Cardigan, Welsh Water has identified a process using moving bed bio-reactors. This process has proven to be the most effective in reducing the severity of incoming seawater, helping to reduce its impact and improve resilience at the works.

This will result in a £20m investment to change the process of the Cardigan wastewater treatment works and help reduce the spill frequency from the site.

Work to install the new treatment works is due to begin in April 2025, and is expected to be completed by April 2027. In the meantime, Welsh Water is planning to install a temporary package treatment plant this month to help treat some of the stormwater entering the works.  This will remain in place until work to replace the treatment works at Cardigan is completed.

The news has been welcomed by Save the Teifi campaigners, however questions are still being asked as to why it has taken Welsh Water so long to accept the treatment plant's failings.

"I've attended so many meetings over the past few years where Welsh Water has never once admitted that the plant was incapable of doing its job," said long-time campaigner Piers Partridge.

"In my opinion, that amounts to lying.

"For over 300 days a year, probably since before records began, the treatment works have been releasing all this untreated water into the river, and it's extremely worrying that it's taken two years of campaigning for us to finally get to this stage."