You must not use pesticides and biocides in or near water unless they are specifically approved for that use.

Chemicals Regulation Directorate: Approved and withdrawn Plant Protection Products

Requirements for spraying near watercourses

You must have approval from your environmental regulator before using herbicides on aquatic weeds or weeds on the banks of watercourses such as rivers, ditches or lochs/loughs.

In Scotland:

Pesticide must not be applied within 1m of any river, burn, ditch, wetland, loch, transitional or coastal water unless:

  • the pesticide is approved for aquatic use and are applied according to the approval
  • it is applied for the control of invasive non-native species
  • no pesticide enters the water environment
  • the ground is not frozen, snow covered or waterlogged
  • it is not applied to impermeable surfaces that drain into water unless measures are put in place to prevent runoff entering the water.

For certain pesticides that you apply using ground crop sprayers or broadcast air-assisted sprayers you need to maintain an aquatic buffer strip between the area you spray and watercourses. The product label will specify the width of the buffer strip that you will have to maintain.

Under certain circumstances, and depending on the pesticide used, you may be able to reduce this aquatic buffer.

If you want to reduce the width of this strip you will also need to carry out and record a Local Environmental Risk Assessment for Pesticides (LERAP).

In Scotland pesticides cannot be applied to, or allowed to drift over, land that is within 1m of any river, burn, ditch, wetland or loch, as measured from the top of the bank (unless it is specifically to control an invasive non-native species, and no pesticide enters the water)(GBR 23).

HSE: Local Environmental Risk Assessment for Pesticides

Aerial spraying

Notify the relevant authorities before aerial spraying

If you carry out aerial spraying you must make sure that:

  • the spraying is done in line with an approved Application Plan
  • specific spraying operations have been permitted by the Health and Safety Executive's (HSE) Chemical Regulation Directorate (CRD).

HSE: Aerial spraying permitting arrangements

Deal with pesticide or biocide spills

You must contain any spills and call the as soon as possible. If a spill enters the sewer, you must tell your water and sewerage company immediately.

Further information

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