What to do about rodents

We understand that seeing a rodent in or around your home can be very distressing. That’s why we want to give you all the information you need to get the problem dealt with as soon as possible by the right people.


If you see a rodent or evidence of rodent activity, your first point of contact is your local authority. They have the duty and the power to take reasonable steps to make sure their district is free from rats and mice.  


Find your local authority’s rodent advice (opens in new window). 


We'll attend if the local authority has investigated and identified that the problem clearly relates to our sewer network. We are committed to working closely with local authorities to deal with rodents.

Responsibilities – who does what?

The images show a typical layout of the drains and sewers around your homes.


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What we do after you've consulted your local authority

Once we have received notification from the local authority, we follow this process for dealing with rodent sightings:

  • Carry out up to three cycles of rodent baiting in manholes within the affected area. A site visit will be carried out after each cycle of baiting to see whether any bait has been taken.
  • If any bait has been taken, we will re-bait the manholes.
  • If after three cycles the bait is still being taken, the matter will be referred to one of our Technical Support Advisors to assess whether further investigation, or further baiting, is needed.
  • If we find that the bait has not been taken, this would suggest that either the rodent activity is not sewer-based, or if it was, activity has now stopped. In either case, we could not carry out any further work.

We are unable to bait any private manholes, these are the responsibility of the homeowner.

Who is responsible for the manhole? 

A typical layout of house drainage is shown to help you determine if a manhole on your property is private or our responsibility.

Typical house layout of your house drainage.png


You need to determine if there is any rodent activity. The examples of manholes we are responsible for are shown below.


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Is the area clear from debris? 

Are there any signs of food waste or fly tipping etc? If so, we would not be able to bait in these areas until this rubbish and/or food source is removed (please use link above to report it to your Local Authority). This is because rodents will always look for food source. Baiting the underground sewers would not help in areas like those below.


Rodents food source.png

More questions about rodents

Rats are mainly active at night but may be seen during the day searching for food, water or shelter. The following are indications of rodent activity:

  • Rat droppings. Rat droppings are capsule-shaped, black and up to 12 millimetres long. Fresh droppings will be soft and moist.
  • Rat runs. Rats tend to stick to the same routes. Look for trails through grass and low vegetation.
  • Burrows. Rats build tunnel systems. Look for entrance holes which may be up to 120 millimetres in diameter and are most likely to be located at the edge of paving and around drain covers, under tree roots and in grassy banks.
  • Nests. Nests will sometimes be found indoors, under floorboards or in lofts.
  • Gnawing. Rats chew continually. Look for gnaw marks on cables, pipe work and wooden fittings.
We can all help prevent rat infestation.

  • Keep your home in good repair as rats can enter through a gap as small as 15 millimetres.
  • Remove any potential nesting sites by keeping yards and gardens clean and tidy, and cut back any overgrown areas.
  • Make sure that drain inspection covers are in place and in good repair.
  • Be aware that Compost heaps – Any food source would attract rodents
  • Seal gaps around heating and water pipes.
  • Ventilation bricks and slots should already have a fine wire mesh incorporated. If this is worn, replace it externally with 3.15 millimetre insect mesh.
  • Don’t leave household waste where rats can get access to it. Keep dustbin lids and composters closed and don’t feed wild birds to excess – you may be feeding rats as well.
  • Keep in mind that putting fat, grease and food scraps down sinks can not only block your drain and cause flooding, it is also an attractive food source for rodents.
  • Interceptor caps in manholes are there to prevent odours only, a missing cap will not be the cause of rodent activity.
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