Private sewage systems

Private sewage systems can include:

• Sewage Treatment Plants (STPs)
• Septic tanks
• Cesspools
• Drains and sewers that run into private systems

The owner of the property or properties that use the private system is responsible for it. Private systems are not owned and maintained by Anglian Water.

Information for private sewage system owners

If you experience any flooding externally or internally that involves the discharge of sewage, you should contact your local councilenvironmental health department or the Environment Agency.

Private/Package Sewage Treatment Plant issues

Waste produced by a Sewage Treatment Plant should look clear. If it isn’t, there could be a fault with the plant.

Common faults include:

• Pump or mechanical failure
• Internal blockages
• Build up of settled solids
• Too much flow

If the plant isn’t working properly you should get advice from a sewage treatment contractor.

Waste may not drain away effectively due to high water levels in the ground or watercourse.

This could be due to lack of maintenance or a blockage in the watercourse. You may need to clear an obstruction and/or maintain the watercourse to enable your plant to drain.

Maintaining a watercourse

You should check whether you have riparian rights for the section of the watercourse that your system drains into . This will tell you whether you are able to carry out works on the watercourse.

If you do not have riparian rights to carry out works on the watercourse and it is within an adjacent property owner’s land, you should get their permission to carry out works on the watercourse.

If you are unsure whether you have riparian rights to carry out works, you should seek independent legal advice to clarify your riparian rights and responsibilities.

Watercourse changes that affect your system

If the watercourse your system drains into has:

• Been filled/blocked
• Had a pipe installed that restricts the waste flow from your system

It may be possible for the relevant authority to take action.

If your watercourse is part of a main river then you should contact the Environment Agency (opens new window) and not Norfolk County Council.

If your watercourse falls within an Internal Drainage District then you should contact the Internal Drainage Board responsible for that area and not Norfolk County Council.

Find contact details for your Internal Drainage Board. (opens new window)

If your watercourse is not part of a main river or in an Internal Drainage District, you should contact Norfolk County Council's Flood and Water Management Team as Lead Local Flood Authority.

The Lead Local Flood Authority will:

• Determine whether the obstruction poses a risk to properties
• Follow impact criteria to determine whether Flood Investigation or Enforcement should be initiated

To initiate action we must have:

• Received evidence that a property or adjacent properties have internally flooded; or
• Identified that the location or properties at risk of flooding are located within the Environment Agency Risk of Surface Water Flooding Maps (opens new window).

We’re unable to take action if:

• Properties have not been internally flooded
• Properties are not at risk of flooding
• There is no evidence to suggest that the contravention ‘has or is likely to cause any increase in flood risk’

In circumstances where the risk relates to a potential nuisance rather than flood risk, we are unable to act. You may wish to seek independent legal advice.

Any sewage discharge could also constitute a statutory nuisance (Section 79, Environmental Protection Act 1990) due to inefficient working of the treatment plants (or any sewage being discharged into the downstream watercourse).

Further information

For further information on sewage package treatment plants, please contact the Environment Agency.

For information on registering, siting and discharging systems to surface waters in more detail, pleaseread the guidance on septic tanks and treatment plants on Gov.uk (opens new window).

You can get advice on the legal status and technical compliance of your system (including access for maintenance/design and construction/size of pipes/materials used) from your local council. This includes advice on compliance with Building Regulations Part H.

Your local council has permissive powers to undertake works on any drainage likely to be prejudicial to health (Section 260, The Public Health Act 1936) - contact your local council for more information.