Nature-based Solutions

Nature-based Solutions (NbS) protect, sustainably manage and restore natural or modified ecosystems to address challenges whilst providing benefits to people and nature. They work by including natural processes in water management. These processes can reduce the amount of harmful nutrients in water, increase the retention of water to mitigate the effects of drought, reduce the risk of flooding because of heavy rain, or prevent erosion of coasts and estuaries. They also support biodiversity and nature recovery by creating a variety of habitats for wildlife. They can work alongside or instead of more traditional (grey) infrastructure.

Human-manufactured solutions that mimic natural behaviours (for example, digging ponds to slow the flow of water and improve water quality) can also be considered NbS.

The Environment Agency supports NbS as they can increase resilience to flood, drought and climate change while providing benefits to nature and society. You can read our organisation-wide NbS position statement on gov.uk. You can also listen to our Director of Water, Helen Wakeham, on CIWEM's Planet Possible podcast. Alongside Mark Lloyd of the Rivers Trust and Niki Roach of CIWEM, they discuss the launch of the position statement, barriers and opportunities to NbS, and how a system-scale approach might allow for more innovative solutions to problems, taking the EA's new position statement as a jumping-off point.

Because NbS cover so many different types of processes, we have developed specific position statements that help guide anyone involved in planning, building, or using a nature-based solution, including water companies, environmental NGOs, and other regulators. We've summarised the key positions from each one in a paragraph below, but each document is available in full by clicking the link.


Using NbS to treat wastewater and improve water quality

We see the benefits of NbS and consider them worthwhile exploring their use in treating wastewater. However, the evidence base is not yet strong enough to fully rely on them to meet statutory water quality requirements.

The Environment Agency are supportive of water company trials using NbS to help meet statutory permit limits for nutrients if the trials:

  • are within the law and meeting permit requirements
  • provide clear evidence that NbS can reduce nutrient levels reliably over time and in different conditions

You can read more about trial eligibility, regulatory and legal requirements for NbS trials, and what our next steps are for supporting trials in our position statement on NbS and wastewater.


Treatment wetlands and green house gases

While wetlands can remove nutrients and provide habitat, they also release greenhouse gases. It is currently uncertain whether the carbon they store outweighs the gases they emit.

Our "Treatment wetlands as greenhouse gas emitters, sinks and stores" statement sets out the Environment Agency’s view on the climate impacts of using wetlands for treating wastewater. It focuses specifically on Free Water Surface Integrated Constructed Wetlands (FWS ICWs), the most common type of treatment wetland in the UK.

In short, our position is that Free Water Surface Integrated Constructed Wetlands (FWS ICWs) for wastewater treatment:

  • emit greenhouse gases,
  • do not act as long-term carbon stores or sequester carbon,
  • some processes in a FWS ICW can act as carbon sinks, which can result in carbon accumulation. However, it is highly unlikely that an FWS ICW could provide an overall net global cooling effect during its service lifetime.


NbS and flood resilience

We also use NbS to reduce the risk of flooding, an approach known as natural flood management (NFM). These processes protect, restore, and mimic the natural functions of catchments, floodplains and the coast to slow and store water.

NFM measures can include:

  • soil and land management
  • river and floodplain management
  • woodland management
  • run-off management
  • coast and estuary management

You can learn more about how this works, and the projects we’re supporting with our partners, by reading about our Natural flood management programme on GOV.UK.


Case studies

We'll be exploring the many different nature-based solutions we're involved in across the country. You can also explore some completed projects in Oxfordshire, the Peak District, and Manchester as part of the case studies section of our position statement.

Restoring a chalk stream to its natural course

Location: River Misbourne, Buckinghamshire

Partners: Affinity Water, Environment Agency, local landowners, CaBA Catchment Partnership, local stakeholder groups

The problem: The River Misbourne was historically straightened and diverted to power Quarrendon Mill. This artificial channel was overwide and perched above the valley bottom, leaving it disconnected from the chalk water groundwater table. As a result, the river could not support diverse wildlife and was less resilient to flooding and drought.

The nature-based approach: Specialist contractors restored 500m of river by creating a new meandering channel that follows its original natural course through the valley bottom. A wetland area was established alongside the restored channel, providing vital habitat for wildlife and natural flood storage capacity during winter months.

Our role: The Environment Agency identified the potential for this project and led stakeholder engagement to define the scope. We developed both outline and detailed designs in collaboration with stakeholders and obtained all necessary permits and permissions to enable construction. We continue to monitor hydrology and ecology to track benefits as the ecosystem matures.

The results:

  • Hydrology and ecology benefits will take time to emerge – baseline data was collected before construction to measure progress as the ecosystem matures.
  • Bird species including white and yellow wagtails and ringed plovers are already using the new wetland (monitored by the Bucks Bird Club)
  • Enhanced habitat expected to attract brown trout and kingfishers as the ecosystem matures
  • Improved river resilience to both flood and drought conditions
  • Progress towards ‘Good Ecological Status’ under the Water Framework Directive

Part of the Revitalising Chalk Rivers programme, this project shows how restoring natural river processes creates thriving habitats whilst building climate resilience - turning back the clock on historic modifications to let nature flourish.

Protecting groundwater through regenerative farming

Location: North Hertfordshire

Partners: Affinity Water, local farmers (N Focus Farmers Group), Oakbank Game & Conservation, Farming & Wildlife Advisory Group (FWAG) East, Environment Agency.

The problem: Nitrate run off from farmland impacting Affinity Water’s groundwater sources.

The nature-based approach: Instead of expensive engineering solutions, local farmers worked to adopt regenerative agriculture practices.

Over 6,500 hectares of farmland now uses cover crops and companion planting - nature-based techniques that protect soil during winter, improve soil health, and prevent nitrate leaching into groundwater. Farmers in the most sensitive areas formed an 'N Focus Farmers Group' to share knowledge and trial innovative approaches, like growing beans and oats together to naturally fix nitrogen from the atmosphere.

Our role: the Environment Agency linked the actions and learnings from the catchment scheme to the relevant safeguard zone action plans, sharing knowledge through regular liaison meetings and annual scheme progress reports.

The results:

  • Estimated 315 tonnes of nitrate prevented from entering groundwater between 2020-2025
  • £6 of natural capital benefits for every £1 invested (Atkins Realis)
  • Healthier soils supporting both nature and farming productivity
  • A growing community of farmers championing regenerative practices

This project shows how working with nature delivers benefits for water quality, wildlife, soil health and farming resilience - all at the same time.


Nature-based Solutions (NbS) protect, sustainably manage and restore natural or modified ecosystems to address challenges whilst providing benefits to people and nature. They work by including natural processes in water management. These processes can reduce the amount of harmful nutrients in water, increase the retention of water to mitigate the effects of drought, reduce the risk of flooding because of heavy rain, or prevent erosion of coasts and estuaries. They also support biodiversity and nature recovery by creating a variety of habitats for wildlife. They can work alongside or instead of more traditional (grey) infrastructure.

Human-manufactured solutions that mimic natural behaviours (for example, digging ponds to slow the flow of water and improve water quality) can also be considered NbS.

The Environment Agency supports NbS as they can increase resilience to flood, drought and climate change while providing benefits to nature and society. You can read our organisation-wide NbS position statement on gov.uk. You can also listen to our Director of Water, Helen Wakeham, on CIWEM's Planet Possible podcast. Alongside Mark Lloyd of the Rivers Trust and Niki Roach of CIWEM, they discuss the launch of the position statement, barriers and opportunities to NbS, and how a system-scale approach might allow for more innovative solutions to problems, taking the EA's new position statement as a jumping-off point.

Because NbS cover so many different types of processes, we have developed specific position statements that help guide anyone involved in planning, building, or using a nature-based solution, including water companies, environmental NGOs, and other regulators. We've summarised the key positions from each one in a paragraph below, but each document is available in full by clicking the link.


Using NbS to treat wastewater and improve water quality

We see the benefits of NbS and consider them worthwhile exploring their use in treating wastewater. However, the evidence base is not yet strong enough to fully rely on them to meet statutory water quality requirements.

The Environment Agency are supportive of water company trials using NbS to help meet statutory permit limits for nutrients if the trials:

  • are within the law and meeting permit requirements
  • provide clear evidence that NbS can reduce nutrient levels reliably over time and in different conditions

You can read more about trial eligibility, regulatory and legal requirements for NbS trials, and what our next steps are for supporting trials in our position statement on NbS and wastewater.


Treatment wetlands and green house gases

While wetlands can remove nutrients and provide habitat, they also release greenhouse gases. It is currently uncertain whether the carbon they store outweighs the gases they emit.

Our "Treatment wetlands as greenhouse gas emitters, sinks and stores" statement sets out the Environment Agency’s view on the climate impacts of using wetlands for treating wastewater. It focuses specifically on Free Water Surface Integrated Constructed Wetlands (FWS ICWs), the most common type of treatment wetland in the UK.

In short, our position is that Free Water Surface Integrated Constructed Wetlands (FWS ICWs) for wastewater treatment:

  • emit greenhouse gases,
  • do not act as long-term carbon stores or sequester carbon,
  • some processes in a FWS ICW can act as carbon sinks, which can result in carbon accumulation. However, it is highly unlikely that an FWS ICW could provide an overall net global cooling effect during its service lifetime.


NbS and flood resilience

We also use NbS to reduce the risk of flooding, an approach known as natural flood management (NFM). These processes protect, restore, and mimic the natural functions of catchments, floodplains and the coast to slow and store water.

NFM measures can include:

  • soil and land management
  • river and floodplain management
  • woodland management
  • run-off management
  • coast and estuary management

You can learn more about how this works, and the projects we’re supporting with our partners, by reading about our Natural flood management programme on GOV.UK.


Case studies

We'll be exploring the many different nature-based solutions we're involved in across the country. You can also explore some completed projects in Oxfordshire, the Peak District, and Manchester as part of the case studies section of our position statement.

Restoring a chalk stream to its natural course

Location: River Misbourne, Buckinghamshire

Partners: Affinity Water, Environment Agency, local landowners, CaBA Catchment Partnership, local stakeholder groups

The problem: The River Misbourne was historically straightened and diverted to power Quarrendon Mill. This artificial channel was overwide and perched above the valley bottom, leaving it disconnected from the chalk water groundwater table. As a result, the river could not support diverse wildlife and was less resilient to flooding and drought.

The nature-based approach: Specialist contractors restored 500m of river by creating a new meandering channel that follows its original natural course through the valley bottom. A wetland area was established alongside the restored channel, providing vital habitat for wildlife and natural flood storage capacity during winter months.

Our role: The Environment Agency identified the potential for this project and led stakeholder engagement to define the scope. We developed both outline and detailed designs in collaboration with stakeholders and obtained all necessary permits and permissions to enable construction. We continue to monitor hydrology and ecology to track benefits as the ecosystem matures.

The results:

  • Hydrology and ecology benefits will take time to emerge – baseline data was collected before construction to measure progress as the ecosystem matures.
  • Bird species including white and yellow wagtails and ringed plovers are already using the new wetland (monitored by the Bucks Bird Club)
  • Enhanced habitat expected to attract brown trout and kingfishers as the ecosystem matures
  • Improved river resilience to both flood and drought conditions
  • Progress towards ‘Good Ecological Status’ under the Water Framework Directive

Part of the Revitalising Chalk Rivers programme, this project shows how restoring natural river processes creates thriving habitats whilst building climate resilience - turning back the clock on historic modifications to let nature flourish.

Protecting groundwater through regenerative farming

Location: North Hertfordshire

Partners: Affinity Water, local farmers (N Focus Farmers Group), Oakbank Game & Conservation, Farming & Wildlife Advisory Group (FWAG) East, Environment Agency.

The problem: Nitrate run off from farmland impacting Affinity Water’s groundwater sources.

The nature-based approach: Instead of expensive engineering solutions, local farmers worked to adopt regenerative agriculture practices.

Over 6,500 hectares of farmland now uses cover crops and companion planting - nature-based techniques that protect soil during winter, improve soil health, and prevent nitrate leaching into groundwater. Farmers in the most sensitive areas formed an 'N Focus Farmers Group' to share knowledge and trial innovative approaches, like growing beans and oats together to naturally fix nitrogen from the atmosphere.

Our role: the Environment Agency linked the actions and learnings from the catchment scheme to the relevant safeguard zone action plans, sharing knowledge through regular liaison meetings and annual scheme progress reports.

The results:

  • Estimated 315 tonnes of nitrate prevented from entering groundwater between 2020-2025
  • £6 of natural capital benefits for every £1 invested (Atkins Realis)
  • Healthier soils supporting both nature and farming productivity
  • A growing community of farmers championing regenerative practices

This project shows how working with nature delivers benefits for water quality, wildlife, soil health and farming resilience - all at the same time.


Page last updated: 17 Dec 2025, 04:53 PM