Guidance

Assess water environment impacts for woodland creation proposals

Updated 26 June 2026

Applies to England

Woodland creation and the water environment

Forests and woodlands are closely linked to water resources, water quality, flood risk management and river water temperature.

Sustainable forest planning and management is essential to maximise the benefits and minimise the risks to the water environment.

Benefits of woodland creation to the water environment

Well-designed new woodlands can:

• maintain or improve soil infiltration and soil water storage capacity
• influence the timing of water delivery during heavy rainfall to reduce flood flows
• minimise soil and bankside erosion
• provide a buffer from upslope activities and improve water quality by reducing sediment and pollutants from runoff
• provide shade along streams, reducing water temperature and protecting aquatic habitats

Read more on the benefits of woodland creation: Woods and Water.

Risks of woodland creation to the water environment

Forests that are poorly designed and managed, or planted in unsuitable locations can:

• increase the effects of acid deposition
• cause eutrophication
• increase sediment delivery
• reduce ground and surface water resources
• obstruct the drainage of flood water
• degrade aquatic habitats, resulting in the loss of aquatic wildlife, damaging fish populations and dependent fisheries

Poor forest planning, implementation and subsequent management in locations near drinking water sources can also cause problems. It can increase water treatment costs and impact public health. This can lead to the suspension or even permanent closure of public water supplies. Private water supplies are particularly vulnerable to disturbance. This is because they often undergo limited or sensitive forms of water treatment.

You can mitigate the potential risks of woodland creation on the water environment by following UK Forestry Standard (UKFS) good practice.

Water environment considerations and constraints

There are potential constraints, risks and pressure factors associated with creating new woodlands.

There are also many benefits for the water environment by planting the right tree in the right place. Adhere to the UKFS to mitigate any water pressures and deliver the greatest possible benefits to the water environment.

Read Forestry project checks: constraints for considerations you should make in your woodland creation proposal. Check if any of the constraints apply to your woodland creation proposal and follow the relevant next steps.

When you know the potential size of your woodland creation proposal, you should check if you need to submit an Environmental Impact Assessment (EIA) application form to the Forestry Commission.

Ground and surface water resources

Trees and woodlands use more water than other types of vegetation. Woodlands intercept rainfall, evaporate leaf surface moisture, absorb moisture in their roots and increase soil infiltration. This can influence the amount of water available to and from groundwater, surface watercourses and waterbodies.

In areas where water is scarce, large scale woodland creation may be detrimental to water supplies, freshwater life or wetland habitats. The impact of woodland creation depends on the land use before planting and the nature of the proposal.

Good forestry practice requires proposals to consider the sensitivity of downstream waterbodies and wetlands. This may include a potential reduction in water quantity when planning woodland creation.

The Forestry Commission will use the new water resources assessment process agreed with the Environment Agency to review how your woodland creation proposal may affect ground and surface water. This will determine the risk posed and provide mitigation options should your proposal require it.

Constraints

Vulnerable waterbody catchments
Groundwater dependent terrestrial ecosystems

Water quality and supplies

It is a legal requirement to protect the quality of drinking water in the UK. There are regulations in place to safeguard public and private supplies.

Communities may be concerned that woodland creation could influence the reliability of water yield or introduce risks of pollution. This may require additional controls on activities such as fuel storage, machinery use and chemical application.

It is important to assess how new planting may affect nearby water supply.

Constraints

Acid vulnerable catchments 
Private and public water supply
Drinking water protection zones and nitrate vulnerable zones

Watercourses, floodplains and flood risk reduction

Woodland creation can contribute to protecting communities and infrastructure from flooding. Natural flood management schemes will often use targeted woodland creation in smaller catchments where there are risks of downstream flooding.

Targeted riparian and floodplain woodland creation can:

• reduce downstream flood risk
• improve water quality
• provide maintained access to riverbanks for flood defence works where required
• augment engineered flood control
• desynchronise peak flood flows, which can reduce the impact of flood events

However, forest operations such as cultivation, drainage, road construction and harvesting can sometimes have the opposite effect if not managed in the right way.

If your woodland creation proposal is planned near a main river, flood defence asset or within a main river floodplain, you may require a flood risk permit from the Environment Agency. This depends on the proposal size, planting density and location of any nearby assets or communities at risk. You should speak to the Environment Agency for advice and information first.

The Environment Agency may consider trees and woodland as a flood risk if they are likely to:

• cause damage or endanger the stability of the banks of a main river
• cause damage to any river control works
• divert or obstruct flood waters or affect the drainage of a river
• interfere with regulators access

Planting on the floodplain of ordinary watercourses does not need Environment Agency or LLFA consent. However, if the proposal includes any measures which alter the course or flow of the watercourse, you need to contact the relevant LLFA or IDB to obtain ordinary watercourse consent.

Constraints

Watercourses
Flood risk and flooding infrastructure

Consult stakeholders

To have a UKFS-compliant woodland creation proposal, as part of the EIA afforestation process you must prove that you have consulted relevant stakeholders where required and given any advice due consideration.

From a water environment perspective, this may include:

• lead local flood authorities
• the Environment Agency
• internal drainage boards
• Catchment Sensitive Farming advisers
• your local water company

Lead local flood authorities (LLFAs)

LLFAs take a lead function in managing local flood risks. This can include risks of flooding from surface water and smaller watercourses outside the main river network. They have powers under the Land Drainage Act 1991 to regulate ordinary watercourses outside of internal drainage districts.

LLFAs can:

• issue consents to alter, remove or replace certain structures or features on ordinary watercourses
• enforce obligations to maintain flow in a watercourse and repair watercourses, bridges, and other structures in a watercourse

Contact your local county council or unitary authority to find your LLFA.

Environment Agency

The Environment Agency regulates and maintains flood and coastal erosion risk management activities on main rivers and the coast. They also regulate and monitor water quality and water resources within England. They have a strategic overview of all sources of flooding and coastal erosion.

The Environment Agency can be an LLFA.

Contact the Environment Agency at enquiries@environment-agency.gov.uk.

Internal drainage boards (IDBs)

IDBs are independent public bodies responsible for water level management in low-lying areas. There are currently 112 IDBs in England and Wales whose districts cover 1.2 million hectares. They work in partnership with other authorities to manage and reduce the risk of flooding.

IDBs hold powers under the Land Drainage Act 1991 to request works to maintain a proper flow of water in ordinary watercourses in internal drainage districts. They manage water levels in watercourses and groundwater. They improve and maintain ordinary watercourses, drainage channels and pumping stations.

IDBs manage water levels in drainage districts. These are areas where there is a special need for drainage. They either occur in broad open areas of lowland or within the floodplains of rivers. Local hydrology determines the drainage district each IDB covers. These districts are not affected by political boundaries but follow catchments and floodplain borders.

IDBs can be an LLFA.

The IDB areas map outlines which areas have IDBs and their contact details.

Catchment Sensitive Farming (CSF) advisors

Catchment Sensitive Farming provides localised and confidential advice to farmers to improve water quality and address flood risk and water resource issues.

Local Catchment Sensitive Farming advisors can advise on mitigating impacts on the water environment to accompany tree planting, natural colonisation and increased canopy cover in farmed landscapes.

CSF advisors can also endorse a proposal’s eligibility for England Woodland Creation Offer (EWCO) additional contributions. This applies to proposals that meet water quality and flood risk management criteria but the land falls outside the relevant mapping layers.

If you identify potential water benefits outside of the EWCO maps, speak to your local Forestry Commission Woodland Officer who will discuss the proposal with the local CSF advisor. Alternatively, find your local CSF mailbox.

Water companies

Water companies are responsible for the provision of public water supplies, wastewater treatment and sewerage services. As part of developing a UKFS‑compliant woodland creation proposal, you may need to consult your local water company if there are public water supply sources, abstraction points or water infrastructure on or near your land.

Water companies can advise on:

• the presence of public water supply sources or catchments
• any potential risks to drinking water quality
• protection measures around abstraction points, boreholes and surface water intakes

Find your local water company.

Further advice

Find more information and support on woodland creation and the water environment:

• UKFS practice guides for water management
• How trees can improve water quality and manage flooding
• Tree planting and woodland creation: overview