Flooding
Who to contact in the event of a flood
Immediate assistance and rescue
999 - Call 999 if you are vulnerable or feel that lives are at risk
Urgent but not life threatening
020 7606 3030 - City Corporation switchboard
080 080 7060 - Environment Agency Hotline
080 031 9800 - Thames Water
Non-urgent contacts
Council Homes
Report flooding in and around council homes to housing services
Transport drainage issues
0343 222 1234 - TfL | for drainage associated with bus stops, subways and tubes.
0345 711 4141 - Network Rail | for drainage issues along train tracks.
Gullies and drains
Report blocked gullies or drains - which are not the main sewer and are not on private property - to Flood Risk
Sewers and water supply pipes
- 080 031 9800 - Thames Water
- Report online - Thames Water - Report a problem
Thames Water is responsible for public water supply and wastewater treatment for the majority of London. Thames Water is accountable for when sewers reach capacity due to heavy rainfall or any sewer blockages.
To prioritise longer term work which may be required, complete the sewer flooding questionnaire
River flooding
The Environment Agency is responsible for fluvial flooding of Main Rivers.
- 0845 988 1188 - Flood line
- 0800 807 060 - Incident hotline
- 0370 850 6506 - General enquiries
Groundwater flooding
Please report groundwater flooding to Flood Risk
What are the risks of flooding?
There are relatively small areas of the City that are at risk of flooding. It's vital to know about the risk to your property to be able understand how to prepare for it.
The City of London Strategic Flood Risk Assessment (2023) provides the most up-to-date information on the risks of flooding in the Square Mile. This includes tidal, surface water, sewer and groundwater flooding. Maps showing the extent of each of these can be found in the appendices.
Surface water flooding is one of the City's higher flood risks and as Lead Local Flood Authority the City Corporation is responsible for managing it. There is a 'residual risk' of flooding from a breach in the Thames' defences. The river defences are monitored twice a year and the owner has a duty to maintain them.
Flood Guidance
Whether you are a business, building owner or resident you can take steps to reduce the impact of flooding on you even when it may occur outside of the Square Mile. The City Corporation has created guidance on how businesses, building owners and workers in the City of London can prepare for flooding. This guidance is in the flooding document library.
We recommend that you use a combination of the sites below to access weather warnings and flood alerts. These services can provide enough time for temporary flood protection measures to be put in place. In the event of a possible flooding incident, the Environment Agency and the Met Office provide a suite of services to communicate forecasts and broadcast up-to-date information to the public. These include the following:
Floodline Warning Direct
Floodline Warning Direct is a free 24 hour flood warning service, provided by the Environment Agency, where individuals can register their properties. You are encouraged to sign up for this service. You can opt to receive a warning by telephone, text or email.
Environment Agency
Met Office information
The National severe weather warnings page provides detailed information and navigates the user to other useful information which provides detailed information. The Weather Observation Website (WOW) is a hub for UK weather observations. This service allows anyone to submit their own weather data, anywhere in the world. These observations are a source of real-time information.
Your local media
When the situation becomes a cause of concern for ground, property and life, flood alerts and warnings will be broadcasted on local media (television, radio and the internet).
Business continuity is the capability of your organisation to continue to deliver its products or services following a disruptive incident. Robust business continuity arrangements are essential for businesses of any size - devising strategies to protect your key products, services and critical activities will enable you to trade through a disruption and recover promptly afterwards. You can obtain advice on developing and exercising your business continuity arrangements by contacting the Contingency Planning Team. There is no charge if you are based in the City of London.
All new developments in the City of London should consider the need for a flood emergency plan. This is considered as part of the planning process. The City Corporation is developing guidance on when an agreed Flood Emergency Plan is required, the current draft is available in the flooding document library.