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Using herbicides

We have changed how we regulate the use of herbicides. Please see below for details, our herbicide guidance document can be found here

There are legal rules on the use of pesticides to control weeds growing in water or on land. ‘Pesticides’ includes herbicides as well as insecticides and fungicides. 

Before using herbicides, you should consider all other ways of controlling weeds. If you then decide it is appropriate to use herbicides, we want to be sure that it is used properly, in line with the product label, and by suitably qualified people.

Anyone who wants to use herbicides to control weeds in water (aquatic weeds), or on the banks or banksides next to a watercourse, or any other body of water in Wales, must have our agreement. We offer two types of herbicide agreements; low risk (simple) and higher risk.

Low risk (simple) agreements

You may be able to use herbicides without applying to us, but only if your activity is low risk.

Low risk activities are where:

  • herbicide is used within 250 meters of water, but not actually in or on water, and/or
  • the spray location is within 1500 meters of a designated site boundary, but not actually within a designated site (for example, Site of Special Scientific Interest, Special Area of Conservation, Special Protection Area or Ramsar), and
  • the spray location is not within 1 kilometre of a drinking water abstraction point (including private water supplies), or 500 meters of any other type of water abstraction point

If you’re unsure whether you can meet these low risk location criteria, you can use our herbicide location screening service – see ‘Checking your location’, below.

If you can meet the low risk location criteria and abide by the standards set out below, you can assume we automatically approve the activity.

You must ensure that:

  • The manufacturers’ instructions and the Control of Pesticides Regulations 1986 are complied with
  • Spraying is carried out in the correct conditions, as detailed in the Code of Practice for Using Plant Protection Products, and kept to a minimum
  • No other product (ie an adjuvant) is used, unless it is approved for use in or near water
  • Care is taken to avoid the potential contamination of any nearby surface water or wetlands
  • In general, you should not use long lasting pesticides and pesticides that can spread within any area designated as a ‘source protection zone’ (SPZ) 1, or within 50 metres of a spring, well or borehole
  • No other legal water interests, including private water supplies, are affected
  • When treating in water, a bank down to a watercourse and land within 1 metre of the top of bank, or within 5 metres of the top of bank for tall herbs such as Japanese Knotweed, (ie land immediately adjacent to aquatic areas), the product must be approved for aquatic use. This will be stated in the crops/situations part of the label
  • Whoever carries out the spraying (treatment activity) must be suitably qualified. You can find more information on ‘suitable qualifications’ in the Agreement to use herbicides in or near water – guidance note

Higher risk agreements

If you cannot meet the low risk location criteria or standards, you must apply for a higher risk agreement.

Higher risk activities are where:

  • you plan to use herbicides to control aquatic weeds in or on water, and/or
  • the spray location is within a designated site (for example, a Site of Special Scientific Interest, Special Area of Conservation, Special Protection Area or Ramsar), or
  • the spray location is within 1 kilometre of a drinking water abstraction point (including private water supplies), or 500 meters of an abstraction point

If your activity meets any of the above location criteria, you must complete the higher risk herbicide application form and return it to us at the address below. You should read the Agreement to use herbicides in or near water – guidance note before you apply. 

If you are unsure whether the herbicide you want to us in aquatic situations is safe, the Chemical Regulation Directorate (CRD) provides a detailed list of approved herbicide products for use in and around water. The list includes details of withdrawn products and their replacements.  You should check this list before you apply. 

Checking your location

If you are unsure whether you can meet the low risk location criteria and therefore need a higher risk agreement, we can help you. We offer an herbicide location screening service. 

Please note: We cannot tell you the precise location of some water abstractions. We can only tell you if the screening report returned results within the relevant distance. In such cases, we will advise you to contact the water supplier directly for further information. 

Our location screening will not identify private water abstractions. These abstractions are registered with local authorities. See the ‘Frequently asked questions about herbicide agreements’, below, for more information on private water abstractions.

You can find information on designated sites on the Welsh Government information portal, Lle.

Please email us your request for herbicide location screening service. You must include details of the site location (ie a 12 digit national grid reference), and the full spreading area.  We will always try to respond within 10 working days of receiving a request. If this is not possible, we will let you know.

Where to send your high risk application

Send your completed application form and all relevant supporting information:

By email, to: permitreceiptcentre@naturalresourceswales.gov.uk Use ‘Herbicide high risk agreement application’ in the email title.

By post, to: Permit Receipt Centre, Natural Resources Wales, 29 Newport Road, Cambria House, Cardiff, CF24 0TP

If you know you want to spray during spring and summer, we ask that you submit your application the winter before. We receive low numbers of applications during winter.  This means we can then process your agreement more quickly, and in plenty of time for you to start spraying.

Managing the impact of spraying, upon Honey Bees

You should contact your local National Bee Unit or the Welsh Beekeepers Association to ensure your proposed activities will not adversely impact local Honey Bee populations. 

Information on the potential impact upon Honey Bees from herbicides, can be found in the Code of Practice for Using Plant Protection Products. The Code states that you should inform beekeepers or the local spray liaison officer, 48 hours before applying pesticides at times of year when bees are at risk or if a particular pesticide specifically harms bees. This gives beekeepers time to take any necessary precautions.

Aerial spraying of pesticides and herbicides

The Chemicals Regulation Directorate (CRD), part of the Health and Safety Executive, is responsible for issuing aerial application permits to anyone applying pesticides from an aircraft.     

If you need to apply for one of these permits, we can help you by providing map based information, on request. This information can help you complete the required site based risk assessment. Please email us your request for aerial herbicide spraying map service. You must include details of the site location (ie a 12 digit national grid reference), and the full spreading area. We will always try to respond within 10 working days of receiving a request. If this is not possible, we will let you know.

Frequently asked questions about herbicide agreements

Q: What is a low risk (simple) herbicide agreement?

These are a simpler and quicker way to get our agreement to use herbicides, in certain circumstances. They are only available to activities that meet set location criteria, and are carried out in line with the required standards. Any activity that cannot meet the low risk criteria, is considered higher risk.

Q: What is a higher risk herbicide agreement?

These are all spraying activities that cannot meet our low risk criteria. They involve using herbicide in more sensitive locations. We need to ensure suitable measures are taken to prevent pollution. Customers must send in an application for a high risk herbicide agreement. Please note: these were previously referred to as ‘Complex’ Agreements.

Q: Are all herbicide agreements automatic?

No. Only activities which are low risk are ‘automatically’ agreed. You must be certain that you meet the low risk location criteria and standards. If not, you still need to apply for a higher risk agreement.

Q: Does Natural Resources Wales still offer a free plant/weed identification service?

Yes. If you are not sure what the plants you want to treat, we can help. Talk to one of our officers based in your local area, to arrange sample identification. Please do not send samples to our Permit Receipt Centre or to our central address.

Q: What is a private water supply?

A private water supply is any water supply which is not provided by a water company. The source of the supply may be a spring, well, borehole or surface water (streams, lakes, etc.). A supply may serve a single dwelling, several properties or commercial or public premises.

Q: Where can I find information about private water supplies?

Local Authorities are legally required to maintain registers of private water supplies in their area. You should always check with relevant local authorities.

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