Moving to a home beside a river, brook or ditch raises two separate questions before the removal van is booked: how likely the area is to flood, and who is responsible for the water running past or through the garden. GOV.UK and the Environment Agency answer both. This article summarises four GOV.UK pages: “Check the long term flood risk for an area in England”, “Find out if your property is in an area that has flooded”, “Prepare for flooding” and the Environment Agency guidance “Owning a watercourse” (last updated 12 February 2026). It applies to England only. Scotland, Wales and Northern Ireland have their own services, which GOV.UK links to separately. It is general information, not legal or surveying advice.
Checking the long-term flood risk
GOV.UK provides an online service that shows the long-term flood risk for an area in England. It says the service covers risk from rivers and the sea, surface water, reservoirs and groundwater where data is available. It also shows how climate change might increase the chance of flooding, the possible causes of flooding and how to manage the risk. Anyone unable to use the online service can telephone Floodline on 0345 988 1188.
The limits of the service matter as much as its content. GOV.UK states that it does not tell users how likely it is that an individual property will flood, and that it does not cover flooding from sources such as blocked drains and burst pipes. It is therefore a picture of the area, not a verdict on one house.
Asking for the flood history of an address
Where an area has flooded before, the Environment Agency can be asked for a flood history report. GOV.UK says anyone can request the flood history for the area around an address or postcode in England by emailing the Environment Agency with the full address, including the postcode. If the postcode is not known, a map of the area can be sent as an attachment or online link. There may be a fee depending on how long the report takes to produce, and the Environment Agency will say if a fee applies. The report is sent by email within 20 working days.
The page contains an important warning: the Environment Agency does not have flood records for all areas in England and may not hold data for the area around a particular property. Other sources it names are the lead local flood authority, whose details come from the local council, and the Internal Drainage Board where one exists.
Who owns the stream or ditch?
The Environment Agency’s guidance says people normally own a stretch of watercourse that runs on or under their land, or that sits on the boundary of their land, up to its centre, unless the property deeds say otherwise. It advises checking the deeds if ownership is unclear. The site’s article on reading the title register and plan covers the wider limits of what those documents show.
The guidance defines a watercourse as any stream of water flowing in a defined channel or through an underground pipe or culvert. It can be narrow or wide, natural or artificial, and includes channels that are dry for long periods or do not flow every year. A dry channel filled only during temporary flooding is not a watercourse.
What owners must do
For a stretch they own, the guidance sets these responsibilities:
- let water flow naturally, which may mean removing blockages, fallen trees or overhanging branches where they obstruct a public right of navigation or reduce flow and cause flooding to other landowners, with damages payable in the latter case;
- avoid pollution, and get agreement from the Environment Agency before using herbicides within one metre of the top of the bank;
- not disturb protected species or habitats, birds and their nests, or the spawning or eggs of salmon, trout or other fish; and
- prevent invasive species such as Japanese knotweed from spreading to the wild or to neighbours’ land.
For a main river the risk management authority is the Environment Agency. For any other watercourse it is the lead local flood authority, which is a unitary authority or county council, or the internal drainage board.
Permissions for work near water
Owners have a right to protect their property from flooding and erosion, but the guidance says they must get permissions to build anything in or around the watercourse or within the floodplain if it does not have planning permission. Building anything that could divert water and increase flood risk to others can lead to a liability to pay damages. Permission is needed before changing, removing or building a flood defence on the land, or doing any work within 8 metres of a flood defence, or within 16 metres of a tidal flood defence. An owner may also be responsible for maintaining and repairing a flood defence on their land, so the relevant authority should be asked.
The guidance says permissions and licences are the owner’s responsibility, and that failing to obtain them may mean a fine or imprisonment. On a main river an environmental permit may be needed from the Environment Agency, and on the River Thames an accommodation licence too. It adds that the risk management authorities are unlikely to give permission to build a culvert.
Flood plans
The “Prepare for flooding” guide suggests making a personal flood plan and keeping it in a safe place with essential items such as spare medication, important documents and contact details. Where a property is next to a canal, it says the Canal and River Trust should be contacted to check who maintains it.
The bottom line
For a move in England, GOV.UK offers a long-term area flood check, a flood history report from the Environment Agency that can take up to 20 working days and may not exist for every area, and Environment Agency guidance on watercourse ownership. The deeds decide who owns the stream, and ownership brings duties to keep water flowing and to seek permission before building. The area check does not say how likely an individual property is to flood.