Frequently asked questions

Water is vital to health and wellbeing, to the economic prosperity of the East of England, and to maintaining a thriving natural environment that we can all enjoy.

Yet we face growing challenges to supply. Our region is low-lying, one of the driest in the UK, and especially vulnerable to a changing climate. Drought is set to become more common amid hotter, drier summers, and intense rainfall events are becoming more frequent.

To meet these challenges, we all have to play our part in balancing the needs of society, business, and the environment to enable a sustainable future. We’re already working on new strategic pipelines to move water from wetter to drier parts of our region, installing smart meters in customers’ homes, and driving down leakage.

While all the investments we’re making today will help to keep taps running, the available supply will fall well below the demand for water unless we plan for future resources now.

The proposed new reservoir in the Fens has been identified as a large-scale investment in new water resources that we need and will play a critical role in securing water supply long into the future.

The reservoir is part of our long-term plan to ensure we can continue to deliver enough water to local communities and businesses across our region, including in Cambridgeshire.

For the proposed reservoir in the Fens, half of the water would be for Anglian Water’s customers, and half for Cambridge Water’s.

You can find out more about how we plan future resources by reading our Water Resources Management Plan (WRMP) here. You can also read Cambridge Water’s WRMP here.

Reservoirs contain a volume of water that provides a level of resilience and environmental opportunities that are not provided by other resource options, such as desalination or advanced water recycling, alone.

Reservoirs are sustainable ways of producing resilient, safe drinking water supplies because they take water from river catchments when they have surplus water. They mean we can make the most of wet weather for public water supply, capturing river water and storing it so it’s on tap when needed.

When we looked at where we might best build reservoirs across our broader region, we identified rivers in the Fens as having enough water surplus in the winter to supply the reservoirs. It will make the most of the available resources and provide water to local communities and businesses across our region, including in Cambridgeshire.

Our latest water resources management plan identifies the new reservoirs as crucial investments needed to meet the growing demands on water supplies in the East of England, as well as the other options we’re progressing to manage demand and unlock supply.

Anglian Water is also investigating options for desalination and advanced water recycling projects in our region. Our latest assessments suggest we will need a range of resource options to meet future demands in our region.

You can find out more about our plans for future resources by reading our Water Resources Management Plan (WRMP).

Before our phase one consultation in 2022, we completed a multi-stage site selection process to identify the proposed site. This aimed to make sure we identified a location that would be suitable for hosting a reservoir. Through the process we also sought to minimise impacts on nearby areas and communities and meet planning and regulatory frameworks.

Looking across a broad search area we identified a large number of potential locations and assessed their performance against a range of factors.

The site locations that performed best at each stage were taken forward and assessed again, in more detail, against a range of criteria.

The location chosen was found to be the most appropriate for building a new reservoir during our site selection process and, on balance, performed best across a range of the key factors we assessed.

You can find out more about the process we undertook in our site selection report.

We received really valuable feedback from local people and stakeholders to our phase two consultation and want to thank everyone for taking part. It’s clear people want us to think carefully about effects on place and communities, roads and transport, agriculture and the local economy, and the natural environment. These are important issues for us too.

Many people were positive about our emerging design and vision for the reservoir, and the opportunities it could bring for people, nature and the environment.

Following our phase two consultation, we published a feedback summary report, showing the key issues that people had raised and our responses to them.

The feedback to our second consultation has influenced the development of our proposals shown in in the phase three consultation, including the proposed design for the reservoir and associated infrastructure. People can read more about the role of feedback in developing our proposals in the consultation materials and the Design Refinement Report.

In England, the cost of essential public water supply infrastructure is ultimately paid for by water customers. However, this can be on differing timeframes, depending on how each water company and its projects are financed. It is the role of the regulator Ofwat to oversee this.

In the development phase of the reservoir, the initial funding required to achieve planning consent is financed through customer bills. We have been allocated approximately £460 million for the development of the reservoir by Ofwat in their Price Review 2024 (PR24) Final Determination.

In the delivery phase (when the reservoir is constructed) funding would be via a third party infrastructure partner (IP) which will operate under licence to Ofwat.

Their remit will be building the reservoir and its associated water infrastructure, in accordance with the planning consent, and supplying treated water from the reservoir to Anglian Water, who will then continue to distribute it to customers.

The IP could also be responsible for owning, operating and maintaining the reservoir. We are currently developing and assessing options in respect of the delivery arrangements for the project.

Using a third party IP helps ensure the best possible value for money for customers is achieved through a competitive process. This approach recognises that certain very large projects are outside of the ‘business as usual’ operations and investments of water companies.

The delivery phase funding mechanism for the IP will likely be similar to that used for the Thames Tideway Tunnel project, whereby Thames Water customers currently have repayments to their IP paid through customer bills.

The cost of the project will ultimately be funded via customer bills, given that our customers will benefit from the future water supply. To ensure the best possible value through a competitive process, our regulator Ofwat has proposed delivery mechanisms which involve third party providers delivering and owning these assets.

The cost of the project would be spread across our full customer base over the lifespan of the reservoir.

Our customers can be reassured that we invest every pound in doing the right thing now and for the long term. We believe our responsibility is to them, their communities, and to the environment we look after.

Our vision for the project goes beyond simply creating a new public water supply. We want to create a place where water, people and nature come together.

We see the reservoir as an opportunity to deliver lasting, positive change for nearby communities and the region more broadly. It has the potential to offer opportunities for healthy activities by offering access to outdoor space and nature, while also creating new jobs in areas like water management, land care, recreation, and hospitality. By providing a resilient water supply it could also help support the region’s plans for economic growth, and play a key role in restoring nature and enhancing the local environment.

Where possible, we will consider ways to include features that local communities could value and use. Areas within and around the reservoirs would be opened for public use, and leisure opportunities created on the water and in the surrounding landscapes. New connections from nearby villages are in our plans, so that people can access and enjoy water and nature.

To learn more about our updated proposals for the reservoir please see our phase three consultation- main reservoir site proposals brochure.

We are also developing a socio-economic strategy to consider what opportunities the reservoir could provide to the local economy during construction and in operation. You can read more about this in our socio-economic fact sheet.

One of the key themes coming out of our last two phases of consultations is the desire for the reservoir to be an inviting place to visit. People were keen to see places for activity and recreation, nature and wildlife and many other features that would attract visitors from across the region.

The circular design of the reservoir was first inspired by the area’s ancient history with ammonite fossils – small marine creatures – found in the earth below the site, dating from a time when it was under the North Sea.

Since our first design concept, we’ve retained the circular shape of the reservoir while also looking at ways to recognise the historic Fenland relationship between land and water. Wetlands, wildlife areas, and connecting routes all feature in our latest proposals to reflect this.

The distinctive shape in our design is a deliberately man-made approach, featuring in a landscape that has been shaped and altered by the people living and working here for generations.

The reservoir is being designed to supply enough water for around 250,000 homes. The surface area of the water would cover approximately 5km2, with embankments surrounding this. The main walking route around the crest of the reservoir would be approximately 9.2km, and a walk around the lagoon in the north of the site would be approximately 2.5km.

The water in the reservoir is held by engineered embankments that are built to meet the strict safety standards required by the Reservoirs Act 1975.

All this means that we can be confident that the reservoir can be built to be safe for its whole lifecycle, with regular monitoring, testing and checks as part of the process.

As required by the Reservoirs Act 1975, we have to make sure water can be discharged from the reservoir quickly and safely in the event of an emergency. It’s not something we ever expect to happen, but we must make sure there’s a plan in place to manage this as part of safety legislation.

Our ongoing assessments show that we can safely discharge water into the Sixteen Foot Drain, from there it would be pumped away to sea via St German’s pumping station.

We will also incorporate several other safety features into the design of our reservoir, to ensure we can continuously monitor the reservoir’s integrity and ensure our plans remain highly effective throughout the reservoir’s operation.

We’re seeking to avoid a reservoir with basic, uniform embankment slopes that provide no shelter or integration with the surrounding landscape.

In our phase three design proposals, we show an embankment crest height that varies between 6 metres and 15 meters above existing ground level. Heights are not fixed at this stage and require further investigation and assessment.

Since our last phase of consultation we’ve carried out more work to explore how the embankments could be landscaped in a way that’s thoughtful to what people will see from nearby, and have varied their slope and shape to create a range of experiences. That includes ideas for tree-planting to help soften the appearance of the embankments and blend them into the surrounding environment.

We’ve created new imagery (which can be seen in our phase three main reservoir site proposals brochure) to give people a better idea of what our design proposals could look like from surrounding areas.

Our updated design proposals feature a recreational lagoon in the reservoir's recreational hub in the north west of the reservoir. The lagoon would provide a maintained consistent water level all year round and a beach on the outer edge of the lagoon could help provide easy and safe access to the water. The lagoon could play host to a range of recreational activities such as paddle boarding and kayaking. We’re also assessing opportunities for swimming.

The recreational lagoon in our current designs is approximately 28 hectares and this size could offer opportunity for a variety of activities. The water in the lagoon is considered as part of the operational volume, meaning that in times of extreme drought, it may need to be drawn into the main body of the reservoir and used for supply.

The reservoir would bring a range of opportunities for local businesses.

During construction, the project will create jobs in the construction sector, and we’re keen to support local/regional construction businesses wherever possible and appropriate. We’re also exploring opportunities for skills development and training to ensure the local workforce is equipped to support the project—while also gaining long-term benefits beyond the reservoir itself.

The project could also support local hospitality businesses. While we’ll aim to use local workers where possible, the scale of the project means some workers may need to come from further afield. To support a good work-life balance and reduce carbon emissions, we’re exploring options to accommodate these workers locally. This could bring additional business to local accommodation providers. However, we’re mindful of the need to protect local tourism, so we’re also considering temporary on-site accommodation to help strike the right balance.

Once operational, the reservoir could attract visitors from both the local area and further afield, boosting tourism and creating new opportunities for local businesses such as cafés, shops, and leisure providers.

We understand that our proposals will have an effect on homeowners, landowners and the nearby community. We’re committed to working with everyone as the project develops and want to hear all views on our emerging proposals.

In accordance with the National Policy Statement (NPS) for Water Resources Infrastructure, Anglian Water will seek to minimise the use of Best and Most Versatile (BMV) agricultural land as far as practically possible.

When we were considering locations for the reservoir, the quality of agricultural land and likely significant impacts were considered in the site selection process. Given the size of the reservoir, all the sites we considered had the potential to affect agricultural land.

Given the early stage of the project, we are still working to define our proposals This means the extent of land required for the reservoir itself, it’s associated infrastructure, and any land needed for mitigation including recreational provision, continues to develop. This includes land required on a permanent and temporary basis.

We recognise that people are concerned about what the project will mean for local businesses and employment and are committed to assessing these likely significant impacts as the project develops. The impact on business and employment will be assessed as part of our Environmental Impact Assessment (EIA).

The findings of our EIA work will be consulted on in a future consultation and presented in an Environmental Statement which will accompany our application for consent. The Environmental Statement will include a Socio-economic and Community chapter, which will consider the effect on employment.

The scope of these studies will be agreed with the Planning Inspectorate as part of the formal EIA scoping process. Through these processes we will investigate the likely significant environmental impacts of the proposed project, together with how we plan to reduce or limit these impacts.

Our goal is to ensure a secure and sustainable water supply for everyone in our region—now and into the future. By 2050, we expect to have 38% less water available to supply our customers. This reduction is driven by the need to limit abstraction from sensitive environments, alongside the pressures of population growth and climate change. These factors will also affect local farmers who rely on the drains and ditches of the Fens for the water they use for farming, in line with existing agreements and licenses they hold with the Environment Agency.

The Fenlands are a vital food-producing region, and we recognise the importance of supporting its agricultural heritage and the farmers at the heart of the UK’s food system. That’s why we’re working closely with the Environment Agency, local drainage boards, the National Farmers Union, and farmers themselves to help guide our proposals and ensure we explore opportunities to maintain local flows used for agriculture.

Importantly, the proposed reservoir will be embanked, meaning water will be actively pumped in so it can be stored. This gives us control over how and when water is captured. We plan to take water during periods of high flow—when it would otherwise be pumped away to sea—which could offer benefits such as helping to reduce local flood risk, potentially helping farmers

As the project develops, we will continue to assess how it could support local farming communities and potential impacts on local water resources used by the agricultural industry. Our Environmental Impact Assessment (EIA) will also help us refine our understanding of the project’s effects and inform how we manage water resources to benefit both people and agriculture.

We have carried out a range of surveys that have helped us to understand more about the land we could be working on, and to help us identify any likely significant impacts that we need to consider. This includes geotechnical investigation surveys, as well as non-intrusive studies such as ecological and archaeological surveys.

All our survey findings have been fed back to the design team to help inform their work. We also completed several site visits and walks from local access points, which have helped enhance our understanding and shape our emerging proposals.

We are engaging with statutory organisations such as the Environment Agency and Historic England as we carry out these surveys.

We may need to carry out further surveys but the specific locations for these have not yet been finalised. Our land agent Fisher German will discuss these with affected landowners in due course once more information is available.

You can read more about the latest phase of surveys we’ve been carrying out and what these involve in our fact sheet.

We have considered the potential for environmental impact from the earliest stages of the project.

Environment was a key consideration when we identified the preferred site for the reservoir and has continued to influence our thinking as we’ve developed the plans for the reservoir and the associated water infrastructure.

As with any infrastructure project, the reservoir has the potential to lead to local impacts, but importantly it can also an opportunity to consider ways to support the local environment and wildlife. We’re considering options to do this, as shown in our phase three design proposals.

Protecting and enhancing nature is central to our design of the reservoir. We’ll make sure this remains the case when it’s built, and when it’s in operation. We will undertake Biodiversity Net Gain (BNG) assessments so that we can achieve a minimum of 10 percent BNG, and are exploring ways to create new places for wildlife to thrive.

We will consider and develop our designs in line with the findings from our Environmental Impact Assessment, which we are required to undertake as a nationally significant infrastructure project. The EIA process helps us make informed choices that promote sustainable development and protect the environment.

You can read more about our approach to the environment in our supporting environmental information report.

We are working closely with the flood authorities who play a fundamental role in managing water and flood risk in the East of England, including the Environment Agency, local councils, and internal drainage boards.

We are focussing on how the reservoir itself – including how water is transported to and from them – are designed to cause no increased risk to river flooding, align with other flood risk management schemes, and explore opportunities to minimise flooding.

We are also carefully considering how we manage water and flooding in how we design the reservoir.

For more information, please read our approach to flood risk fact sheet.

We are undertaking modelling of existing ground water levels. The ground water models will help us to understand if there is any potential effect from the reservoir on ground water and if appropriate mitigation impacts could be required.

Our plan is to develop a reservoir embankment and foundation structure using the clay material we know is on site. The clay has low permeability, retaining water in the reservoir and limiting the likely significant impact on ground water.

This approach would help limit the reservoir’s impact on surrounding groundwater levels. Other opportunities in the emerging reservoir design include wetlands and pumping arrangements to manage water movement around the reservoir site.

We are committed to minimising and mitigating the potential impacts the reservoir may have on local roads, as far as is reasonably possible. In addition to our own commitments, we are aligning our approach with the requirements of the National Policy Statement for Water Resources Infrastructure, which sets out the framework for developing water resources such as reservoirs. This includes specific guidance on traffic and transport, which we are actively considering as we develop our plans.

As part of our evolving design proposals, we’ve shared initial ideas on how construction traffic could be managed.

We are also exploring the use of freight transport for materials sourced from further afield. Two potential rail-connected sites have been identified—one linking to the reservoir via the A141, and another that would require a new haul road. We are currently evaluating both options.

To find out more about our construction traffic and transport proposals please see our design refinement report.

We are actively considering the potential local impacts of construction—such as traffic and transport congestion, noise, dust, and pollution—as part of our planning process. To address these concerns, we are working closely with local authorities and will continue engaging with community members to gather feedback. Their input will help shape and refine our proposals to ensure they are responsive to local needs and priorities.

Compensation for those directly affected will be determined on a case-by-case basis depending on the nature of land or interest, and how the project affects them.

We recognise that, in some instances, homeowners affected by our plans for the reservoir need to sell their property but the timeline of our proposals raises questions. It may make some buyers hesitant to commit given our proposals are still at an early stage. Or potentially, there may be concern that a sale now could result in a price that is lower than prevailing market conditions, making the owner unsure whether to sell.

There are all sorts of reasons why people need to sell their property, but if the ability to do that is shown to be affected by our proposals, we want to provide support through the residential property support scheme. It will provide financial assistance should a property sale be clearly affected by our proposals.

While Anglian Water is not required to do this, we think it is an important step in providing support for people most affected by our plans for the reservoir.

You can find out more about our Residential Property Support Scheme here.

We are exploring plans for submitting a local planning application for the enabling works of a trail embankment. This would be a scaled-down version of the final embankment built using local clay and will help us:

• Understand how the clay behaves and how it settles over time
• Confirm our design assumptions and construction methods
• Identify and manage potential risks, helping us refine the overall construction programme
• Provide assurance to Development Consent Order (DCO) reviewers that we’ve done our due diligence

The results of this trial will help shape the final embankment design. We are developing our approach to the trial embankment and will be reaching out again to communities and stakeholders as part of any local planning application.

You find read more about this in our trial embankment fact sheet.

We’re still considering the combination of water sources that may be used to fill the reservoir. Further technical assessments and discussion – alongside your feedback – will help shape our future proposals and inform the final decision.

Read more about the sources we’re currently looking at using in our phase three associated water infrastructure proposals brochure

There are two main construction techniques that we could use to install the pipes- the open method and the trenchless method- depending on the location and nearby features.

We would generally use an open cut method – digging trenches – to install the pipelines but in some cases we would use a trenchless installation method to install sections of pipe, to limit disruption to traffic and services.

We estimate that we would need an area approximately 75 meters wide to install the pipelines. However, in some areas, it may need to be wider – up to 200 meters – to accommodate larger or multiple pipelines within the same corridor.

Read more about this in our phase three consultation associated water infrastructure brochure.

During our phase three consultation for the Fens reservoir project, Anglian Water will also be consulting on the Grafham to Cambridge pipeline project. This forms part of a 70km pipeline designed to transfer water from wetter areas in our region to the drier areas in the south and east, helping to meet the immediate and critical need for water in Cambridge.

Anglian Water, working in partnership with Cambridge Water, will deliver the first section of the project between Grafham and Cambridge. This will include a spur pipeline into Cambridge to supply water into the Madingley Service Reservoir.

Although these will be separate consultations, to support those who may be affected by both projects, we will be holding a joint event at Bar Hill Village Hall on Saturday 8 November, from 10am to 3pm. Both teams will be present and able to answer questions.

Both our project teams are working together to ensure a joined-up approach to engaging with those who may be affected by both projects, as well as making sure that any comments provided that are relevant to both projects are reviewed by both project teams.

You can find out more about the Grafham to Cambridge project on their website:

Yes, the feedback we receive from local people and all our stakeholders is key to making sure we develop our proposals in a way that helps to keep impacts as low as possible and create benefits for people and nature.

All feedback will be considered alongside our technical studies, to help us develop our proposals further.

Our third phase of consultation took place between 15 October and 10 December 2025. So everyone can see the themes and issues raised and how we’re considering them, we’ve published a summary of the feedback, which you can view here.

We received really valuable feedback from local people, landowners and stakeholders to our phase three consultation and want to thank everyone for taking part.

Many people were positive about the potential recreational activities at the reservoir. We received valuable feedback on how often people would travel to the reservoir, and if they would walk, cycle, or drive.

We also received useful comments on our associated water infrastructure proposals, as well as our construction and traffic and transport plans.

Following our phase three consultation, we’ve published a feedback summary report, showing the key issues that people had raised and our responses to them.

Click here to read more.

Consultation is about gathering data to better understand impacts so we can manage them, and what opportunities people want to see achieved as part of the project, so we can assess if that’s possible.

If people have specific requests, we will consider them, but decisions always need to balance a whole range of needs, such as technical and safety requirements, costs, land use, environmental needs and so on. Our aim is always to deliver a project that must communities’ needs with these other important factors.

The consultation in autumn 2025 is our third consultation on the project. There will be at least one more phase of consultation on our proposals before we make our application for development consent.

We’ll keep people up to date via our project website, and you can also subscribe to receive updates via our e-newsletter

The new reservoir is a complex project and it’s important that we develop plans carefully to take account of a whole range of factors.

If the project is consented, we estimate construction to take around six to eight years, with the reservoir providing water by 2036 at the earliest.

You can read more about our plans for construction in our reservoir brochure and associated water infrastructure brochure, available in our document library here

Before any construction can start, we need to continue to progress our application for development consent.