OFWAT’s Innovation Fund outlines its innovative approaches to tackle water pollution in the UK.
Good-quality water is essential for humans and their environment. In the UK, every individual uses about 140L of water every day. While our need for water remains steady, our other activities are seriously affecting the quality of this essential resource.
In the UK, the main causes of water pollution include industrial activities (releasing harmful chemicals and pollutants into water bodies), agricultural practices (carrying pesticides, fertilisers, and animal waste), and urban runoff (including sewage). This increased contamination poses a serious threat to essential natural water sources.
Water pollution has wide-ranging impacts on the environment and human health. Ecosystems suffer from decreased biodiversity and habitat destruction due to pollutants and disrupted food chains. Polluted water sources pose risks to people using the water for leisure, causing gastrointestinal illnesses and other health issues.
Over the past two decades, we’ve seen some improvement in the quality of water in our rivers¹ and coastal areas – and in the biodiversity of some of the wildlife they support.² There are, however, also too many incidents of pollution. And a strong desire from customers and other water users that more is done to protect our rivers, inland and coastal waters. So, there is still significant work ahead of us to address these challenges and ensure further improvements in water quality.
It is, therefore, critical that we work towards a more sustainable water sector and take advantage of technological and innovation advances to do this.
Innovative approaches to tackling sludge
Across the UK and Europe, there is a growing realisation that sludge – a treated combination of solid matter and dead bacteria left over from the treatment process of sewage – poses environmental challenges. It contains microplastics, metals and PFAS (indestructible chemical compounds, also known as ‘forever chemicals’), which can enter the soil and waterways.
The Ofwat Innovation Fund’s most recent innovation competition, Water Breakthrough Challenge 4, was a £40m competition that recognised 17 winners with the potential to deliver wide-scale, transformational change benefitting customers, society and the environment. Among these winners were a number of innovations seeking to better manage and prevent treated sludge as a possible pollutant.
This included the Sewage Sludge Gasification project from Yorkshire Water, which looks to offer an alternative to recycling sludge to land.
The project will use the Advanced Thermal Conversion gasification process to convert treated sewage sludge into usable products such as biochar, vitrified ash ‘stones’, and a hydrogen-rich synthesis gas (syngas). By operating at a high temperature, the process aims to destroy other contaminants, including forever chemicals, including PFAS and microplastics, and ultimately reduce the risk of water pollution.
An added bonus is that everything produced by the gasification can be reused. The biochar, which resembles small pieces of charcoal, will be tested to treat wastewater as an additive in brick manufacturing and as a soil improver to increase water and nutrient retention. As it doesn’t readily decompose, it’s also a vehicle for sequestering carbon in soil — though it must be properly managed to ensure soil ph levels are not negatively impacted.
The vitrified ash ‘stones’ could be used as aggregate in the construction industry to reduce the embodied carbon footprint of concrete. The syngas – a blend of hydrogen, carbon monoxide, carbon dioxide and methane – can be used to produce green electricity, along with other high-value products.
It is clear that as well as helping reduce pollution, innovative approaches to sludge management can benefit a circular economy and encourage a more sustainable society through the provision of outputs such as green electricity.
Another winner from the competition has been funded to explore a similar but different treated sludge transformation process, in this case via pyrolysis. This high-temperature process doesn’t use oxygen but seeks to recycle treated sludge for similar uses – ultimately reducing the need for treated sludge to be spread.
A third project will look into further uses for the biochar that can be produced from this process.
Tech-led approaches to public awareness and education
Although much of the responsibility for pollution management sits with organisations and governing bodies – including the agricultural industry, urban planning as well as water companies themselves — public awareness and education can play a crucial role in reducing water pollution.
The Ofwat Innovation Fund has supported a number of water companies in their ambitions to achieve better customer education around water pollution.
In the latest competition, Severn Trent was awarded £1.8m to pilot an exciting scheme, in partnership with Nectar and behaviour experts, that aims to incentivise customers to reduce their energy consumption through smart meter gamification. The initiative will work by awarding points for water-efficient behaviour, ultimately driving lower water use and reduced energy bills for the customer.
Similarly, Ofwat had previously awarded the citizen science initiative, The Big River Watch, £7m as part of an earlier round of the competition. The project, from a consortium of water companies and partners, including United Utilities, Severn Trent and The Rivers Trust, has led to the creation of an app-based survey that encourages individuals to monitor the local health of their rivers and comment on visible pollution levels, wildlife (indicating health) and their experience of the river.
Innovative educational initiatives, such as citizen science, will be critical in getting the public to engage in monitoring and improving water quality, including awareness of pollution and its impact.
Green infrastructure to reduce and counter water pollution
Some issues related to water pollution can be improved through customer education. Still, much of it needs national-level processes to drive change, which is why Ofwat works so closely with innovation teams at water companies. Through initiatives to address the factors behind pollution, we can begin to instigate the structural changes needed to achieve healthier bodies of water.
Some of these are literally structure-based changes. Over time, built-up areas have become increasingly water-resistant, with paved, non-permeable surfaces leading to increased run-off. This, combined with a changing climate and increased risk of extreme weather such as storms and flooding, can lead to the overuse of sewage overflows.
Introducing green infrastructure to urban environments, such as green roofs and permeable pavements, can absorb and slow down rainwater runoff, mitigating flooding.
Sustainable Drainage Systems (suds) replicate natural drainage processes through features such as ponds and infiltration basins. These systems manage surface water runoff, diminishing flood risk and enhancing water quality while fostering biodiversity.
Suds iq, a national suds collaboration and evaluation platform led by Southern Water and awarded funding as a winner of Water Breakthrough 4, seeks to create a nationwide online platform for Sustainable Drainage Systems (suds) collaboration aimed at enhancing collective understanding of suds functionality and benefits.
This platform will streamline partnership efforts and promote the adoption of environmentally friendly drainage solutions, expediting efficiency and implementation.
Another innovative project that has been awarded funding is developing a market-based approach to deliver suds. For example, the risk of flooding in London due to heavy rain is on the rise. This winning initiative encourages utility companies to fill some of the 165,000 holes they dig in London annually with ‘sustainable drainage systems,’ such as rain gardens, helping to alleviate pressure on drains caused by rainwater and contribute to making the city greener.
A pollutant-free future
It’s exciting to see our Innovation Fund driving so many of the crucial changes needed to reduce pollution and limit the effects of unavoidable pollutants.
Although there is still work to be done, we hope that these projects can pave the way for a cleaner, greener water sector of the future, powered by innovations that benefit society, the environment and customers.
References
- https://environmentagency.blog.gov.uk/2024/01/25/water-transformation-source-to-sea/
- Invertebrate biodiversity is improving in England’s rivers, long-term trends show | UK Centre for Ecology & Hydrology (ceh.ac.uk)
Please note, this article will also appear in the 18th edition of our quarterly publication.