Diffuse pollution

What is diffuse pollution?

Diffuse pollution is the release of potential pollutants from a range of activities that individually may have no effect on the water environment, but at the scale of a catchment can have a significant impact (ie reduction in water quality, decrease in wildlife, etc.).

Diffuse sources of pollution include run-off from roads, houses and commercial areas, run-off from farmland, and seepage into groundwater from developed landscapes of all kinds.

Do the regulations apply to me?

If you undertake any of the following activities, you will require some form of authorisation from SEPA under the Controlled Activities Regulations (CAR):

  • storage and application of fertilisers;
  • keeping of livestock;
  • cultivation of land;
  • discharge of surface water run-off;
  • construction and maintenance of waterbound roads and tracks;
  • application of pesticide;
  • operation of sheep dipping facilities.

Why do they have to be regulated?

Diffuse pollution from land use activities has a significant impact on water quality. To achieve the objectives of the Water Framework Directive (WFD), the quality of Scotland’s water environment must be maintained and, where necessary, improved.

Rural diffuse pollution arises from land use activities such as livestock grazing, cultivation of land to grow crops and from forestry operations. Such activities can give rise to a release of potential pollutants which individually may not have an impact but together, at the scale of a river catchment, can impact on water quality. The pressures and impacts from diffuse pollution are described in the Significant Water Management Issues consultation document and include eutrophication, loss of biodiversity, silting of fish spawning grounds, and impacts on human health through drinking water or bathing water pollution. The pollutants of concern include the nutrients nitrogen and phosphorus, sediment, pesticides, biodegradable substances, ammonia and micro-organisms.

Levels of authorisation

The Controlled Activities Regulations allow for three levels of authorisation:

  • General binding rule (GBR): The diffuse pollution GBRs provide a statutory baseline of good practice and their implementation will help to improve water quality. You will not have to contact SEPA or incur a charge, though you will have to follow a set of rules.

  • Registration: Not applicable.

  • Licence: Not applicable.
What do I need to do?

(Please note: If at any point during the application process you have a query, contact your local SEPA office).

  1. First refer to the pollution control chapter in the CAR Practical Guide pdf link (519k) to see if your activity meets the requirements for a diffuse pollution GBR.

  2. If your activity falls under a GBR you will not have to do anything. If you require a registration or a licence, however, you will need to apply under another regime. Use the menu on the left to select another regime.

Other useful links and information