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EdenTree were delighted to be the guests of Anglian Water on 10th August at two sites serving the Greater Norwich area.

Engaging with Water Utilities: Site Visit to Norwich

Neville White Neville White Head of RI Policy and Research

Engaging with Water Utilities: Site Visit to Norwich

Neville White

Neville White
Head of RI Policy and Research

During the long hot summer, seldom a day has gone by without England’s privatised water utilities coming under intense scrutiny and criticism for the volume of system leaks and pollution overflows into water courses. We explored this subject in our recently published Insight ‘The Condition of Our Rivers’ based on engagement with eight of the combined water and wastewater utilities in which we are invested.

The Insight examined what has gone wrong and made some recommendations which included the need for more intense engagement by investors; with much of the sector privately owned, engagement is disappointingly off the radar of most ESG investors. One further way investors can be fully engaged with the sector is by understanding the complex challenges that exist in bringing clean, potable water day after day to the population of England and treating wastewater for safe return to watercourses. One way of doing this is by visiting infrastructure to better understand the full end-to-end water cycle process.

To that extent we were delighted to be the guests of Anglian Water on 10th August at two sites serving the Greater Norwich area.

Water Treatment – Heigham

Heigham Water Treatment Works has supplied clean water to the City of Norwich and its environs for over 100 years, and the site contains historic Victorian architecture and state-of-the-art water treatment facilities. The current plant dates from 1994 and can handle 60 million litres a day of treated water ready for the tap! Water is drawn from the River Wensum and stored in a large reservoir before undergoing several intense processes; ozone is used to destroy organic compounds, then an iron-based compound removes 90% of suspended solids before the water is passed through a series of sand and carbon filters.

Finally, the fully treated water is pumped into the network ready for use. The series of treatments water is passed through before it is fit for use – water has to be 99.9% ‘pure’ under Drinking Water Inspectorate rules – amounts to an amazing engineering feat.

The Heigham plant, although over 100 years old, has the largest submerged ultraviolet filtration system in the UK with the largest surface area of submerged membranes in Europe (above). This system represented a £36m investment in water infrastructure to ensure resilience and continuity of supply for decades to come.

Moreover, this investment ‘builds in’ additional capacity as the population of Norwich continues to grow, placing increased demand on the need for water. A full tour of the plant showed us just how complex the challenge is, and how Anglian Water is investing in resilience and water security to the highest standards.

Wastewater Recycling – Whittlingham

The other half of the water cycle equation is the treatment of foul water and effluent, and so the second half of our day with Anglian Water saw us journey to the Whittlingham Water Recycling Centre (WRC) which again serves the Greater Norwich area in respect of treating sewage and solids.

The plant’s origins are also over a century old. However the modern plant comprises state of the art technology for dealing with wastewater. On arrival solids are removed for onward processing, with the wastewater then diverted through a series of processes that include filtration, disinfection and aeration before the water is of a quality that can be returned to the river system.

Millions of litres a day are treated and returned ready to begin the cycle all over again. We were able to see at the outflow just how clean the water is that is being returned to the River Yare. CSOs or combined sewer outflows have become particularly controversial as these are designed to operate only in times of extreme weather to avoid effluent backing up into homes and businesses.

Storm water as it enters the plant is stored in six enormous storm tanks (above), and only when these are full is the water diverted back into the river – this is usually a heavily diluted mix of rainwater and effluent.

As well as handling millions of litres of wastewater every day, the plant at Whittlingham also treats waste oils on contract (we saw several lorries delivering waste oils whilst on site) and other solids via its Cambi plant (below). Cambi, another EdenTree holding, is a world leader in thermal hydrolysis, an advanced treatment for sewage sludge that exposes the sludge to high pressure and temperatures to release energy and gas.

These in turn are captured and can provide a valuable additional income stream, whilst the solids are treated into a nutrient rich and odourless fertiliser that Anglian Water sells into the agricultural sector. An extraordinary biproduct of this process is that so much heat is produced that Anglian Water has worked with Low Carbon Farming to power two vast tomato greenhouses, together providing 10% of the UK’s tomatoes.

Anglian Water are particularly proud of their ‘no waste’ approach in which every part of the treatment process can produce something of value; the only solids so far going to landfill are the rags and wet wipes removed at the start of the process, and even here, they are looking at how valuable cellulose can be released from the waste and repurposed.


The current concern surrounding the performance of water companies hides a more subtle and important story; one that is seldom told – that every-day billions of litres of water are safely treated and delivered to homes and businesses throughout the land; raw sewage is treated to the highest standards via a series of highly engineered processes. We should rightly be proud of this achievement, without losing sight that more needs to be done to reduce leaky infrastructure and to make the network more resilient – especially in order to adapt to expected population growth and escalating climate change.

About Anglian Water: Anglian Water is the largest English water region by geography. It supplies water and wastewater recycling to a population of around seven million people in the East of England and in Hartlepool. Anglian Water operates more infrastructure than any other region with 143 water treatment works supplying over 1 billion litres of water every day and 1,128 water recycling centres that treat 927 million litres of wastewater every day. Anglian Water also manages 38,185 km of water mains and 76,000 km of sewers.