Southern Water has a long history of treating customer water and wastewater to a high quality while protecting the natural environment it works in – but it knows it can do more to reduce its carbon footprint, improve the environment and continue to deliver a sustainable service to customers.

In AMP6, Southern Water decided to review its processes to see how it could work towards a circular economy approach to resource management – where resources are reused as much as possible rather than disposed of. Currently the water company recycles around 700 megalitres (million litres) of reclaimed water per day and generates 17 per cent of its own energy from renewable sources, including CHP and solar power.

“While this is a great start, we want to go further,” says Elin Williamson, Research and Development Manager at Southern Water. “We are investing in new research and trials and working with cutting-edge technology partners to make the biggest impact we can.”

Southern Water’s Bluewave innovation programme aims to find new ways of increasing the value it gives customers while at the same time protecting the environment, and through Bluewave, it is a key partner in a multi-million pound European project which looks at harnessing resources from wastewater.

The New Energy and Resources from Urban Sanitation (NEREUS) project has eight partners which are all contributing their specialist knowledge and skills. They include water companies, wastewater and academic institutes from across Belgium, France, the Netherlands and the UK. The project will receive €3.4 million of funding from the Interreg 2 Seas Regional Development Fund and continue throughout 2019 into late 2020.

The overall project aim is to look at resource recovery from wastewater, which could include energy, nutrients (like phosphorus or nitrogen) or water re-use. Southern Water’s part in the project is to focus on nutrient recovery, trialling how nutrients can be recovered from its wastewater treatment processes.

It will conduct a trial of technology to recover calcium phosphate (which can be used as a fertilizer or other products) and struvite (as fertilizer). Trials are taking place at Peel Common Wastewater Treatment Works, which serves a population of 250,000 in Fareham, Hampshire.

“This is an ambitious goal for us, as the technology for nutrient recovery is still in its infancy and not completely proven at a large scale,” Elin adds.

“By collaborating with so many other water companies, we’re able to work closely with others and access crucial data, technical results and provide market-leading information on resource recovery technology. This approach gives us much stronger benefits and cost-effective research as we’re able to tap into the research done by the other companies as well as their leading expertise, while also contributing our own.

“As well as the collaborative approach and what can be achieved by all of the partners involved, for us it’s about creating value for our customers and driving a circular economy. 

In layman’s terms, re-using and recovering energy from our wastewater and gaining wider benefits from it, like promoting crop growth. A lot of our work here at the moment is in the planning and trialling, working with four other partners to trial technologies and processes. We need to test and demonstrate the viable options before anything becomes permanent.

“Being part of such a huge EU-wide project is exciting and nutrient recovery could be an area for future opportunity and investment. The EU funding allows us to be more ambitious in developing a technology trial and testing the feasibility of a bigger nutrient recovery unit.”

Of course, trialling the technology (while working with technology supplier and support partner Royal HaskoningDHV) is only part of the solution. Nutrient recovery is a new field and hasn’t been used at very large scales in wastewater.

The University of Portsmouth, based in Hampshire, is one of the world-class academic partners in NEREUS. They are leading on the main output of the project, which is the design and development of a Decision Support Tool (DST) for the selection of wastewater recovery technologies and the life cycle assessment.

Academics from the University’s School of Mathematics and Physics and the School of Civil Engineering and Surveying are collaborating with HZ University of Applied Sciences in the Netherlands and EU pilot partners to develop a DST, which aims to aid the decision-making process for the selection of technologies for resource recovery depending on the scenario characteristics.

Dr Seda Sucu, a Research Fellow in Applied Operational Research in the School of Mathematics and Physics, working under the supervision of Professor Djamila Ouelhadj, Lead Academic from the University of Portsmouth, is one of the team members leading the design and development of the online tool that will aid the resource recovery trials.

Dr Sucu said: “One of the main outputs of this project will be the design and implementation of a DST to assist decision makers in selecting the optimal resources and technologies in a range of wastewater recovery and treatment scenarios. The DST will consider a variety of technologies proposed by pilot partners, as well as technical, economical, environmental and socio-cultural criteria.

Professor Djamila Ouelhadj said: “This is an amazing opportunity for the University of Portsmouth to be involved in a project of this scale and to collaborate with academic and industrial partners from Europe to develop the green economy and transform wastewater into water reuse, nutrients, and energy.”

The NEREUS project’s overall aim is to boost the development of the green economy and transform wastewater into a valuable source water, nutrients and energy that can be reused in the Interreg 2Seas area. This area covers coastal regions along the Southern North Sea and the Channel area, of which England, France, the Netherlands and Belgium are members.

Adds Elin: “We’re looking forward to applying the benefits of the project learnings to managing resources in the future.”

For further reading on Interreg 2 Seas Programme, visit: www.interreg2seas.eu and for the NEREUS project, see www.nereus-project.eu/about/

For more information about this work and the project as a whole, please visit:

www.southernwater.co.uk/waste-management and www.southernwater.co.uk/innovation-blogs to find out more about Southern Water’s innovative projects.