Who to contact
Find out the roles, responsibilities and contact details of different organisations who manage flood risk.
In this section
Surface water
Surface water flooding occurs when heavy rain can't be absorbed by the ground or drains. Water flows over the surface and gathers in low areas. This is the biggest flood risk for Hillingdon residents.
Water is captured by gully pots at the side of most roads and flows into Thames Water sewers. Our highways teams clear over 36,000 gullies in Hillingdon each year, and they focus more often on priority areas.
After heavy rain, water on roads or open land is expected, despite preventive efforts. This can be due to blockages in other parts of the drainage system.
However, if water is still present after a few hours and you believe the issue is being caused by a blocked or damaged gully, you can report this to us using our online form, which you can also use to report a missing gully cover.
Please note: Gullies on private roads are the responsibility of the landowner, often shared between residents.
Report a blocked or damaged gully
You can also tell us about a problem with a roadside ditch.
Report a roadside improvement or corrections
Rivers
All rivers are the responsibility of landowners known as riparian owners.
The Environment Agency maps main river and coastal maintenance work in high-risk areas. If you see a blockage or tree causing flood risks, call 0800 807 060.
Ordinary watercourses, including small ditches and rivers, are managed by landowners and mapped by the council.
If a landowner plans to pipe, alter a pipe, or dam an ordinary watercourse, they need to apply for council consent by emailing flooding@hillingdon.gov.uk or calling 01895 556000.
The highway authority doesn't own roadside ditches, they belong to the adjoining landowner unless used for new roads.
Groundwater
Groundwater flooding occurs when the water table rises, causing water to surface and flood areas, typically after long periods of heavy rain.
Heavy rain can cause road flooding. If this happens, we will post updates and advice on our social media. Please reconsider if your journey is necessary.
Sewers
Thames Water is responsible for sewers in Hillingdon.
If you think there is a blockage, report it on Thames Water's blockages and blocked drains page. For sewer flooding, use the sewer flooding page page or call 0800 316 9800.
Please note: To help prioritise any necessary long-term work, you can fill out the sewer flooding questionnaire and post it to Thames Water Customer Services, PO Box 508, Swindon, SN38 9TU.
Properties
Maintaining your property includes taking care of your front garden and drainage system.
Pipes and drains
- A drain is the property owner's responsibility until it connects to either someone else's drain or is a public sewer.
- The water utility company is responsible for maintenance and repairs to:
- private sewers that you share with another property
- sections of your property's drains that lie outside the property boundary.
- To clear blocked drains, contact a plumber, drainage engineer, or water utility, who will charge for the service. Insurance is available for drains within your property boundary.
Council-owned properties
If you live in a council-owned property and have an issue within your home, you can report it online. You can also use our form to report drainage issues from another property affecting your home.
Canals
The Canal and River Trust is responsible for the canals in Hillingdon.
For non-emergency related matters, call them on 030 3040 4040.
For emergencies, call the 24-hour number on 080 0479 9947.
Reservoirs
Hillingdon has several reservoirs, managed by different companies and landowners. Typically, a reservoir is a large natural or artificial lake, pond, or impoundment created with a dam or lock to store water.
Go to next section: What is being done to reduce flood risk?