River Tweed Commission

Established by Order under an Act of Parliament to protect the fish stocks in the Tweed River System


start_stop end_stop1

Disinfection against G. Salaris

Damp or wet equipment, wetsuits, canoes or fishing equipment, which has been abroad, can carry the deadly parasite Gyrodactylus salaris for up to 7 days. Therefore any such equipment must be disinfected before it is used in the River Tweed or its Tributaries.

There are four methods which can be used to disinfect equipment for Gyrodactylus salaris before it enters the river. The first three are preferred methods:

  • Drying to a minimum of 20o C for at least 2 days – initial use of a hair dryer may be useful
  • Heating to above 60oC for at least one hour
  • Deep freezing for at least one day
  • Alternatively, a chemical method can be used as follows but this is substantially more complex and may be corrosive to equipment:

Exposure of materials to a solution of, or addition of, one of the following chemicals to water to the concentration indicated for a minimum of 10 minutes.

  • Virkon 1%
  • Wescodyne 1%
  • Sodium chloride (common salt) 3%
  • Sodium hydroxide 0.2%
  • These chemicals are available from agricultural chemical suppliers. The use of trade names is for illustrative purposes only and does not signify endorsement of any particular product.


Disinfection Procedure for Virkon:

WARNING: Chemicals may damage or discolour some equipment

Virkon power is a dangerous irritant and should be treated with great care according to the manufacturer’s instructions. To use as a disinfectant:

  • Follow the manufacturers instructions for making up the solution and use appropriate protective clothing, masks and goggles as per those instructions.
  • Either:
  • a)Use a hand sprayer with a fine mist to cover equipment in solution for at least 10 minutes [preferred],
  • Or:

    b) Make up a solution in a suitable container and immerse equipment for at least 10 minutes.
  • If you have a waste/spent solution to dispose of then the options are to:
  • Discharge it to a Scottish Water or Northumbrian sewer system [preferred]
  • Discharge to land, however this requires a groundwater authorisation from SEPA or the EA which also entails a prior assessment, an application fee plus annual subsistence.
  • It should NOT be discharged via a septic tank or directly to any water.

Solutions of Virkon become inactive after 7 days or once the colour is lost and should be replaced as required


RTC Logo

Established by order under The Scotland Act 1998 (River Tweed) Order 2006