Trade effluent FAQs

Why do I need a trade effluent consent?

If you want to discharge trade effluent into the public sewer, you will need permission from us before you are allowed to do so. We need to protect the environment and maintain our assets, sewer networks and treatment works. In order to do this, we need to control what is being sent to the public sewer on a daily basis. This is set out in the Water Industry Act 1991.

How do I find out if I already have consent?

We have a public register containing all active consents. Link to trade effluent public register

You can search the United Utilities trade effluent public register to determine if a specific site has consent using one of the following:

  • the legal company name
  • street name or postcode of the site discharging
  • consent reference number if known

What about mobile businesses?

If your business does not have a permanent discharge point from where you discharge trade effluent to sewer, but your business involves going on to sites that use a permanent connection, then the waste you produce may need an agreement from us. Please contact your retailer who will provide you with the relevant application form to complete and submit on your behalf. All discharges must be made to the foul sewer.

What about temporary discharges?

Temporary discharges are generally for groundwater remediation or construction projects. For a discharge to be deemed temporary it should be for less than 6 months duration and authorisation is by agreement. For discharges exceeding 6 months full consent will be required. Any discharge must be to the foul sewer and not to the surface water system. Please contact your retailer who will provide you with the relevant application form to complete and submit on your behalf. 

What about commercial swimming pools?

United Utilities considers the backwash water from swimming pools to be in a low risk category and that issuing formal trade effluent consent is not appropriate control for the level of risk. As such we will not normally pursue an application for a ‘Consent to Discharge’.

The position statement above applies to the routine discharge of filter backwash water. If you need to empty the content of a swimming pool the following process should be followed.

Swimming pool emptying position:

  • You must obtain formal approval from United Utilities prior to emptying the swimming pool contents
  • The discharge point and rate for emptying into the public foul sewer will be determined and agreed
  • This requirement shall relate to each and every pool emptying event

Please contact your retailer if you need to make an enquiry to discharge the pool content. The following information should be included in your enquiry to enable us to assess the request:

  • Name of Company
  • Contact name and details including email
  • Site address – This is the site address where the swimming pool contents are being discharged from
  • Maximum volume to be discharged m3/day
  • Discharge flow rate l/sec
  • Street name where discharge will be made into the public foul sewer
  • Start date
  • Completion date

What about undertaking a Trade activity at a domestic property?

If you undertake a trade activity at a domestic property, resulting in a wastewater discharge from that activity, you will need approval from United Utilities prior to any discharge taking place.

Please send your enquiry to and provide the following information so we can assess your request:

Customer name:

Premise address including postcode:

Contact Telephone number:

Email address:

Full Description of activity:

Water supply account number (found on your water bill):

Confirm if a water meter is installed at the domestic property Y/N:


What if I am not connected to a sewer?

Trade effluent should only be discharged into a foul or combined sewer; you will need to inform us if you want to make a connection to the public sewerage system. We need to ensure that the connection is made in the right place, in the right way and by the right people. This is really important to stop problems occurring, such as blockages and sewage flooding. We also need to make sure that you connect into the right type of sewer (for example, ensuring that foul waste does not enter into a surface water sewer, as this can lead to pollution of a nearby river or stream). You can use the following link to find out more about this service connecting to a public sewer.

What do I do if I can’t discharge to a sewer?

Where we can, we try to accommodate your trade effluent discharges. However, there will be instances when this will not be possible (for example, you do not have access to the public sewer, or your trade generates waste that is deemed unsuitable because of the risk of harm to people, assets, and the environment). In these instances, waste may be removed from site by tanker and treated at a waste management centre. In line with other waste management companies, we offer this tankering service to business and domestic customers. You can use the following link to find out more about this service Tankered industrial and domestic waste

What about surface water drainage?

Trade effluent control applies only to those discharges made to the foul sewer. No discharge of trade effluent should be made to the surface water sewer; this includes vehicle washes, wheelie bin cleaning and condensate from steam boiler systems. It is your responsibility to ensure drains on your site are identified correctly and any trade effluent discharge is directed to the foul sewer. (If you are an occupier on site, your landlord should have copies of the site drainage). Surface water drains should be protected with bunds and/or other containment systems to prevent contamination from the site process or potential pollution from spillages.

What will my trade effluent consent contain?

Any form of authorisation issued by us is likely to contain the following limits:

  • a limit on the maximum daily volume, and on the maximum discharge rate
  • a limit on the concentration of solid particulates and other organic matter
  • any substance likely to produce flammable, harmful or toxic vapours will not be permitted – such as petroleum spirits or derivatives of.
  • the pH will be restricted between set levels.
  • effluents with a temperature higher than 43.3oC (109.9oF) will not be permitted.

We will set any appropriate conditions to ensure that discharges do not cause problems in the sewer network or at sewage works, interfere with sewage treatment processes, affect any watercourse or pose a threat to the health and safety of our employees or the general public.

What happens if not all my wastewater goes back into the sewer?

As a business customer, you pay for all the water that passes through your meter, so if any of your water is used in a product or does not return to sewer, (e.g. evaporation) you may be eligible for an allowance. Please contact your retailer who will provide you with the relevant application form to complete and submit on your behalf. 

What do I do if the nature of my business changes?

Your trade effluent consent is issued specifically in the name of your business (at the address of your trade premises) and only permits you to discharge effluent specified in the consent. However, consent conditions can usually be varied as required. You must give us at least seven days' written notice of any of the following:

  • any change to the process or the process materials or any other circumstances likely to alter the constituents of the trade effluent
  • any change to the name of your business/partnership
  • a change of ownership of the business premises

On receipt of this information we will issue a new consent if there is a change to the legal entity name, or issue a variation to the original consent subject to any new substances and limits identified. On issue of a new consent or variation of an existing consent, further variation cannot be served by us within two years of the date of issue (unless authorised in writing by you).  

What do I do if my trade premises move?  

Consents are not transferrable and therefore a new consent will need to be issued.

If you do any of the following:

  • sell the company to a new owner,
  • are taken over by another company,
  • merge the company with another company,
  • change the legal status of the company from that to which the original consent was granted

you will need to apply for a new consent. Failure to do so will mean that the discharge is illegal. (However, this would not apply where the company forwards a Certificate of Incorporation to us.)

Please contact your retailer who will provide you with the relevant application form to complete and submit on your behalf.

What happens if I cease trading?

If you cease trading at your current premises, or even if you just no longer discharge trade effluent to the public sewer, you should inform your retailer in advance. They will provide you with the relevant application form to complete and submit on your behalf.

What happens if my discharge breaches any of my consent conditions?

Your local Trade Effluent Controller will provide you with analysis results for every sample taken from your premises (normally via e-mail), so it will be easy for you to keep a record of your compliance. If the discharge exceeds any of your consent parameters, your local Trade Effluent Controller will contact you. 

If compliance is not achieved, we may be forced to take legal action. More detail can be found in our enforcement policy (PDF 352 KB opens in a new window).