Biosecurity for everyone Download this page in pdf format

Everyone visiting a water body is responsible for helping to avoid the spread of non-native species on their clothes, equipment and everything else that comes into contact with water.

This guidance sets out simple instructions that can help everyone prevent the accidental transfer of non-native species.


  • Non-native species could be spread in any water or material. If you are visiting a water body there is a real risk that you could spread harmful organisms unless you follow good biosecurity practice.
  • Biosecurity means taking steps to make sure that good hygiene practices are in place to reduce and minimise the risk of spreading invasive non-native species. A good biosecurity routine is always essential, even if invasive non-native species are not always apparent.


  • Make sure you are aware of some of the priority non-native species.
  • Where possible posters and signage should be put in place to make people aware of the risk, and provide advice on how to prevent spread.
  • Ideally, access and egress to the water body should be limited, preferably to a single point.
  • Any site may have invasive non-native species and diseases that can be spread by contaminated clothes and equipment, so good biosecurity is always important. Remember: everyone, every time, everywhere.
  • If you are visiting a site where an invasive non-native species is known to be present, you must ensure you don't spread it. Failure to do so risks prosecution under the Wildlife & Countryside Act, 1981.
  • Risk can be reduced by reducing the contact time in which equipment is exposed to the water.
  • Anything that comes in contact with the water, including boots, could accidentally spread non-native species and should be carefully cleaned.

Actions for field surveyors in particular

  • Plan visits so that the most risky visit is the last one of the day.
  • Arrive at the site with clean footwear and vehicle.
  • Ensure footwear is clean (visually from soil and debris) before leaving the site.
  • Ensure vehicle is kept clean - in particular remove any accumulated mud before leaving the site.
  • Make use of facilities provided on the site to clean footwear/equipment.
  • Keep access to a minimum. If practical do not take vehicles onto premises, keep to established tracks and park vehicles on hard standing.
  • Where possible avoid areas of livestock and areas with known plant disease.

Check, Clean, Dry disinfection procedure

  • Check - All clothing and equipment should be thoroughly inspected and any visible debris (mud, plant or animal matter) should be removed and left at the water body where it was found. Particular attention must be paid to the seams and seals of boots and waders. Any pockets of pooled water should be emptied.
  • Clean - Equipment should be hosed down or pressure-washed on site. If facilities are not available equipment should be carefully contained, e.g. in plastic bags, until they can be found. Washings should be left at the water body where the equipment was used, or contained and not allowed to enter any other watercourse or drainage system (i.e. do not put them down the drain or sink). Where possible, clean equipment should be dipped in disinfectant solution (e.g. Virkon) to kill diseases, but note this is unlikely to kill non-native species.
  • Dry - Thoroughly drying is the best method for disinfecting clothing and equipment. Boots and nets should be hung-up to dry. Equipment should be thoroughly dry for 48 hours before it is used elsewhere. Some non-native species can survive for as many as 15 days in damp conditions and up to 2 days in dry conditions, so the drying process must be thorough.

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