Your FAQ

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Your FAQ 2016-12-13T09:49:54+00:00
WM Donald Drainage Services
WM Donald Drainage Services
WM Donald Drainage Services

FAQs for Homeowners

What’s the difference between a drain and a sewer?

A drain is a pipe that carries sewage and/or surface water from a single property. They are often referred to as private drains because responsibility for clearance and maintenance lies with the owner of the property.

A lateral drain is the section of a private drain normally outside the boundary of a property to the point at which it connects with a sewer.

A sewer is a pipeline carrying sewage and/or surface water from more than one property. These can sometimes be referred to as common drains – i.e. a drain with numerous shares, passing through clearly defined boundaries or curtilages*.

*For a legal definition of curtilage see:

How do I know if my drains are blocked?

If your drains are blocked this will usually be indicated by your waste failing to get away when you flush the toilet, or gullies outside overflowing. There will also probably be a smell around drains and inspection chambers. If the problem is in the main drain, then other services such as the kitchen sink and wash hand basins may be slow to drain.

What should I do if my drains are blocked?

Firstly, try to establish if the blockage is localised, i.e. prior to or confined to the house connection. Remember the rule of gravity – drains always run downhill, for example if the upstairs toilet is blocked but the downstairs toilet is clear, then the blockage is likely to be at the back of the WC pan. If the drainage assets such as gullies are overflowing outside, then this is indicative of a blockage in the main drain as more than one facility is affected.

In Scotland, responsibility for clearances and repairs to private drains rests with the property owner. If you have a shared drain with neighbours, then those upstream of you derive benefit and are partially responsible as such. Check to see if you are covered by any insurance schemes, most insurance companies provide cover for underground drainage assets should costly repairs be required, although you may need to pay any excess on your policy once cause of damage has been determined.

If you cannot clear the blockage yourself, then you can contact a specialist drainage contractor such as WMD Drainage Services. WMD Drainage Services has a ‘duty of care’ for it clients. We will always let you know if a drainage problem, other than a routine blockage, may be covered under an insurance policy. Our engineers are insurance experts in claims validation and can assist you in preparing reports for your insurers as required.

It is worth remembering that while your insurer may appoint their own ‘approved’ contractor to carry out investigation works to find the cause of any damage, you are entitled by law to appoint your own contractor to carry out the actual repair works.

What should I do if there is a blocked or defective sewer?

If you suspect the blockage is outside the curtilage/boundary of your property and within a common drain/sewer or in the public sewer it may be advisable to contact the local water authority to report the problem on Freephone 0845 600 8855.
If you live in rented accommodation and have a drainage problem, contact your landlord or housing association.
Pipes and other drainage assets that are not the responsibility of the local water authority include:

  • Water supply pipes within your boundary
  • Existing surface water drains that do not connect or drain to public sewers
  • Privately owned pumping stations or sewage treatment works and connecting pipes
  • Privately owned septic tanks or cesspits.

However, if you experience a problem with any of the above we may be able to offer advice and help

I have water in my garden from a watercourse. What should I do?

If you have water in your garden that is related to a watercourse, you should contact SEPA on 03000 996699:

For further information visit:


» A guide to drains and sewers
(credit: Scottish Water)

» A guide to surface water drainage
(credit: Scottish Water)

» Sewers for Scotland
(credit: Scottish Water)

» Confined Spaces
(credit: Health & Safety Executive)

» HSEQ Certification

» SEPA Certification

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