Environmental guidance for your business in Northern Ireland & Scotland

Disposal to water where no public sewer is available

Disposal of effluent to water

You might be able to pump your trade effluent to the nearest public sewer.

Alternatively you may be able to treat the effluent on site before discharging it to surface waters or groundwater.

What you must do

Before you discharge treated trade effluent you must have:

  • in Northern Ireland a discharge consent, groundwater authorisation or pollution prevention and control (PPC) permit from the Northern Ireland Environment Agency (NIEA)
  • in Scotland an authorisation under the Controlled Activities Regulations (CAR). CAR requirements are also meet within authorisations under  pollution prevention and control (PPC) permit, Waste Management Licence (WML) or the Radioactive Substances Act from the Scottish Environment Protection Agency (SEPA).

If you have an authorisation (including consent, licence or PPC permit) it will specify the maximum concentrations of pollutants allowed in the effluent. You will need to decide how to achieve these limits. You may be able to change your processes, or you could consider using an effluent treatment system (such as package treatment plants or septic tanks).

If possible you should look at the possibility of using a soakaway to land. This requires a large enough area of land to be available. The land must also be well drained, not waterlogged, and have a sufficient depth of soil. If no land is available then additional treatment can be achieved using reed beds or gravel filter beds, though these are not usually accepted in Northern Ireland.

You must not discharge trade effluent into a surface water drain, surface waters or groundwater without prior permission.

If you are setting up a new business you should investigate effluent disposal before you choose the location of your business.

Further Information

Preventing water pollution

GPP4: Treatment and disposal of sewage where no foul sewer is available (PDF 245 KB) [PPG under review]

DAERA: Regulating Water Discharges

Septic tanks

Back to Trade effluent home page

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