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Water companies pledge to protect rare chalk streams

A group of water companies have today vowed to invest millions of pounds to protect the country’s chalk streams by reducing the amount of water they abstract from them for public drinking supply and cutting pollution.

The pledge was made at an online Chalk Stream Summit organised by the Chalk Rivers Action Group (CRAG) and attended by Water Minister, Rebecca Pow, along with representatives from several environmental groups plus senior leaders from Thames Water, Anglian Water, Affinity Water and Southern Water.

At the summit each water company laid out its plans to stop the decline of English chalk streams and reverse the decline so their flows, health and ecological status recover and are protected in the future. This included stopping sewage discharges into chalk streams from sewers and treatment sites, which are currently permitted during and following heavy rain to alleviate pressure on the system and reducing or stopping the abstraction of water from vulnerable chalk streams.

Attendees also heard how cross water company and regional level planning will help ensure demand for water from households, businesses, industry and agriculture can be met in the future without such reliance on chalk streams through the development of new sources of water, increased storage such as new reservoirs, and reducing demand through consumer education and metering.

Sarah Bentley, Thames Water CEO, said:

“Chalk streams are a breathtaking and an invaluable part of our natural heritage and I’m absolutely committed to ensuring we’ll play our part in restoring these iconic water bodies to their former glory.

“In 2017 we announced we would seek to close all our abstractions from vulnerable chalk streams, where supported by our customers, and I want to reassure you I fully support this ambition but also recognise we need to go further. Restoring and protecting chalk streams requires a team effort and I look forward to working with government, regulators, public bodies, environmental NGOs, and the local communities to deliver activities on the ground. We’ve already made good progress and have ambitious plans for the future.”

Peter Simpson, Chief Executive of Anglian Water said:

“We’ve already begun to see the environmental benefits of taking a catchment-based approach in our region. We fully support exploring new ways to work in partnership to restore, enhance and protect the unique chalk streams across the East of England.

“Over the next five years we’ll be investing £811 million protecting and enhancing the environment in our region, including millions which will go towards improving river water quality. But we recognise there’s even more to do, which is why we’re already working with Defra to outline how we can to go even further, and faster, as part of our commitment to ensuring a green recovery post covid-19.”

Affinity Water’s director of corporate affairs, Jake Rigg said:

“Chalk streams are a precious part of our local and national heritage and a priceless natural resource. This is the decade where we will either protect and enhance the environment for every generation or fall further behind. We recognise this is not a new issue, but it is clear that we need to act with urgency.

“This is why on World Rivers Day in September, we announced that we stopped taking water from boreholes at the top of the Chess Valley and committed to end unsustainable abstraction from chalk groundwater sources in our supply area.

“We will follow up these changes in this Chess catchment by significantly reducing groundwater abstraction in the Ver and Mimram catchments in 2024.

“We also need to work differently to ensure that we can build on the actions in the Chess, Ver and Mimram, as soon as possible, to benefit all of our chalk rivers.”

There are only 200 chalk streams known globally, 85% of which are found in the UK in southern and eastern England. While some chalk streams, notably the Kennet, Lambourne, Test and Itchen, benefit from formal designations under the EU Habitats Directive, many, such as the Chess in the Chilterns, do not.

Paul Jennings from the River Chess Association said:

"Like all chalk streams the River Chess is a rare and fragile ecosystem. For it to thrive we need reliable flows and clean unpolluted water. These are the fundamental issues for all rivers, for the Chess, with recently announced reductions in abstraction and the planned upgrading of the Chesham Sewage Treatment Works, progress is being made.

"With these important foundations we can build for the river's future by improving habitat and migration pathways. With this we can create greater connection and access for all stakeholders, including schools, universities, walkers, nature enthusiasts, fishermen and farmers. Working with the Chiltern Chalk Stream Project, Wildlife Trusts, Affinity Water, Thames Water and the Environment Agency will be essential for the success of this vision."

Individual water company commitments:

Thames Water

  • Increase capacity at Chesham sewage works by 30% by 2023 so more wastewater can be stored and treated reducing the need for discharges to the River Chess. Also increase capacity at Berkhampstead sewage works and reduce phosphorous levels from both sites.
  • Stop infiltration of groundwater and surface water into the sewer network. This will reduce the likelihood of the network being overwhelmed and excess flows entering waterways through CSOs.
  • Stop all abstraction from Hawridge on the River Chess by the end of 2024. To achieve this £40m will be invested in an alternative source of water for the 12,000 customers who currently get their water from Hawridge. The project will reduce overall abstractions from the Chiltern Chalk Streams by 80% compared to 1990. To date abstraction has already been reduced by 63%.
  • Work with Affinity Water to establish a new set of chalk stream health metrics to establish what “good” looks like for a chalk stream.
  • Green recovery - Proposing to accelerate programme to reduce sewage spills to the environment in three environmentally sensitive catchments, including the River Chess, and reduce groundwater infiltration by lining 260km of sewers in 50 vulnerable catchments. This would be done with additional investment beyond the PR19 settlement to support economic recovery from the COVID-19 pandemic.
  • Grow Smarter Water Catchment Initiative which goes beyond the water industry to identify all the pressures on a river and work with all partners to address them. Working with key groups such as the River Chess Association the initiative takes a more holistic approach to catchment management. A first of its kind in the UK, it expands beyond water quality improvements and looks to assess the benefits of addressing multiple challenges together e.g. will finding solutions that value biodiversity gain, flooding prevention and access to blue/green spaces equally, be a more cost-effective way of delivering our services.

 Anglian Water

  • Deliver our largest Water Resources National Environment Plan in 2020-2025, which includes investment specifically targeted to protect chalk streams. The five-year programme totals over £800 million and includes a wide array of river restoration, habitat improvement, river support, sustainability reductions, water treatment wetlands and P reduction.
  • Over the next five years, Anglian has committed to cap all major groundwater aquifers to recent actual levels to avoid deterioration. This equates to a reduction of more than 80 million litres per day which is an industry leading position and made possible through our Water Resources Management Plan 2019 investment. Addressing unsustainable groundwater abstraction is a critical element to the protection of chalk streams.
  • Accepting significantly tighter Hands Off Flow (HOF) conditions on our abstractions linked two critical chalk streams in our region by March 2025, specifically the River Nar and River Lark. Our abstraction will be significantly reduced and will need to cease for long periods meaning we will leave more water in the river, particularly at times of drier weather.
  • Creation of up to 34 water treatment wetlands, building upon the learnings made from our award-winning low carbon wetland at Ingoldisthorpe in Norfolk which provided water quality benefits downstream in the River Ingol chalk stream.
  • Conduct further investigations on 40 combined sewer overflows (CSOs) to assess whether they are having any environmental impact and put interventions in place for those deemed to be the highest risk.
  • Continue to work with environmental charities and local partnership groups to restore, enhance and protect our unique chalk stream habitats across the region. We are also committed to continue to collaborate at a multi-sector level through Water Resources East (WRE) to drive forward the best net benefit solutions and embed a long-term environmental ambition to the east of England.
  • Anglian have set out an ambitious five-point green recovery plan focusing on carbon reduction, housing growth, skills and jobs, climate change and nature recovery to enhance the social and environmental prosperity of the Anglian region.