An upgrade to the Brecon wastewater treatment works is under full swing, in a bid to combat phosphorous levels in the nearby River Usk.

The upgrades – which are being carried out by contractors Mott Macdonald Bentley – will include the introduction of an innovative process, which will remove phosphorous from the treated wastewater, thanks to a £10 million investment scheme currently being delivered by Dŵr Cymru Welsh Water.

Phosphorus is an element essential for plant growth that is in lot of the food we eat and is a key part of fertiliser. When too much reaches the river, it can cause algae growth, which can be harmful.

Now, the wastewater site in Brecon is targeting the levels of phosphorous that enter the River Usk by introducing a phosphorus removal process at the sewage works and increasing the capacity of the site to deal with growth in the catchment.

Steve Wilson, Managing Director for Wastewater services, said: "At Brecon Wastewater treatment works, the treated wastewater discharges into the River Usk. We've been looking at the capital scheme that we are underway with to tackle the phosphorus going into the River Usk. We are looking at ways to target the water quality of the river."

The first part of the work started last year, but from the end of July, the work ramped up even further. This included a larger compound set up within Brecon County Showground. Screens have been put in place to fish out things such as wet wipes, and the hope is that machinery will be replaced next summer.

Subject to Ofwat approval, Welsh Water plans to invest nearly £1.9 billion in the environment between 2025 and 2030 – 84% more than across 2020-25.

However, this will be reflected in the water bills of customers, due to Welsh Water being a not-for-profit company. "At the moment, we are proposing as part of our five-year plan that roughly the bills will go up 20 per cent over five years, plus inflation, and will go up gradually from 2025-2030. It's a big bill increase, but as with the rest of the industry, there is a lot of investment that is needed. The only source of money for Welsh Water is our customer bills. We borrow funds from banks for investments, and then the interest cost and the operating cost for the plant are all paid for by customer bills.

"Each of these schemes costs a lot of money," Steve continued. "We're spending over £10 million here for a population of around 10,000 people. That's a lot of money. We have to repeat this work at lots of treatment works, too. we operate more than 800 in Wales. Thankfully, because of the not-for-profit status of Welsh Water, we have managed to put another £100 million into water quality improvement. £60 million is going to tackle the phosphorous issue, while £40 million is tackling storm overflows. This site is one of those benefitting from the extra £60 million. That means we will have phosphorus removal up and running by 2025, which is a lot earlier than we would have done if we had followed the normal regulating cycle.

"If you think about the River Usk, Brecon is the biggest town along the river. If we're going to try and tackle phosphorous, we need to try and get as much out upstream as we can to improve the river. We've got plans to take it out here at Brecon and Llanfoist, the plant for Abergavenny, as they're the biggest discharges in the river. Other sites are being targeted, too."

Phosphorous can cause algal bloom which can be harmful to the river’s ecosystem. Ensuring efficient treatment before treated water is released back into the environment will help reduce levels in the nearby River Usk - which in turn will benefit the river quality and its aquatic life.

However, upgrades to the wastewater site in Brecon can only do so much, and other issues need to be tackled, such as the phosphate that rolls off farmland during rainfall. "If we tackle phosphorous from our sewage works it's going to improve the river, but it won't bring it back into compliance," Steve says. "All parties need to do their bit if we're going to get the river to meet the right standards."

Protests around the River Usk have been staged throughout the year. Amongst the nine River Special Areas of Conservation in Wales, the River Usk has the highest incidence of phosphorous pollution from agriculture and sewage and is on the verge of ecological collapse. Steve says that the wastewater works has been quick to action changes. "As soon as Natural Resources Wales told us the river didn't meet the right standards, we moved very quickly to do the work to work out where the phosphorus is coming from and then agreeing on a program with investment for the sewage works so we can improve the discharge standards. It's difficult to expand sewage works when we're keeping it running as well, but we're building this over the next twelve months, which is pretty quick for a complex piece of capital investment into live sewage treatment works."

Steve stresses the importance of everyone coming together to make changes to their habits when discarding items that could later cause issues with phosphorous levels and pollution. "If everyone plays their part I think the river can come back into compliance. We'll target the phosphorus coming from the treatment works. Agriculture needs to play its part. People with septic tanks need to play their part, too. People in Brecon need to think about what they're putting down the drain, what they're flushing, how they wash their cars. It's considering that what you're putting down the drain is what you should be putting down there. No wet wipes because they cause blockages and pollution incidents. People who tarmac over their grass for a driveway, with less green infrastructure to soak up the rainwater, make this situation harder to deal with. Everyone has a part to play.

"We get a lot of rainwater coming to the sewage works. Even if someone at home were to have a water butt, if you empty that before the next rain event, it will store a lot of rainwater that doesn't need to come barreling down the wastewater drains as quickly as it does. There are little things we can do. We need more places to soak up the rainwater, and we'll do our bit by upgrading the treatment works, tackling the phosphorus and making sure our storm overflows don't damage the environment."

According to the Welsh Water manifesto for rivers, research shows that the Usk wastewater treatment works contribute 21% of the phosphorus in the SAC waterbody, with Combined Storm Overflows (CSOs) responsible for 1%. The remaining sources have been identified as rural land use and other sources that include private septic tanks and surface run-off.

Welsh Water is also investing £2m in a phosphorous removal project at Llanfoist Wastewater Treatment Works, which is due to begin in August, as well as £10m on the sewage pumping station and wastewater treatment works in Usk, the second phase of which begins in April.

The Brecon Wastewater Treatment upgrade is expected for a completion in July 2024.