Twickenham Policy Unit: Thames Estuary 2100
What needs to be done to manage flood risk and adapt to rising sea levels in Twickenham, one of 23 policy units in Thames Estuary 2100 (TE2100).
Applies to England
Map centred on Twickenham highlighting the policy unit boundary, which includes parts of Teddington to the South, Brentford in the North and Isleworth centrally. Surrounding areas outside the boundary are shown, with the map extending approximately 4 kilometres (km) to the east and west and 1km to the north and south. The flood risk layer shows there is a 0.1% or higher chance of flooding each year in many areas without the existing flood defences.
Description
The Twickenham Policy Unit starts at Teddington Lock, where the tidal section of the Thames begins. It stretches along the north bank of the Thames to Brentford.
The local councils responsible for this area are:
- London Borough of Hounslow
- London Borough of Richmond upon Thames
This area has several Thames tributaries, including the:
- River Crane
- River Brent
- Duke of Northumberland’s River
The tide affects the lower sections of these tributaries.
Use the Thames Estuary 2100 map (TE2100) to view all the policy units.
Local areas at risk and types of flooding
The main areas at risk of flooding in Twickenham are residential.
There are also some important sites at risk, including:
- schools
- a hospital
- major transport routes
- parks and gardens - for example Syon House and Marble Hill Park
The local plan includes 2 new buildings in the Diamond Jubilee Gardens next to the Thames near Eel Pie Island. These will have retail, office space and restaurants with residential homes on the upper floors.
The types of flooding that could affect this policy unit include:
- tidal flooding – when the tide overtops flood defences
- fluvial flooding from the Thames and its tributaries – when heavy rainfall causes rivers to overflow their banks or defences
- groundwater flooding – when underground water stores (aquifers) overflow
- surface water flooding – when heavy rainfall is unable to drain away
- a combination of these
Managing flood risk in this area
The Thames Barrier protects the area from flooding. There are flood walls and embankments along the Thames, the lower Brent and the Crane.
The Environment Agency closes the barrier to prevent storm tides travelling up the river, and to help manage extreme fluvial flooding.
The Crane gates prevent high tides from the Thames entering the River Crane, unless the Crane has higher flows. Raised flood defences help to reduce this impact.
The Environment Agency also uses flood alerts and flood warnings to inform people about potential flooding so they can take appropriate action.
Sign up to receive flood warnings in your area.
Flood risk management policies for this area
Thames Estuary 2100 sets flood risk management policies for each area of the estuary. The policies range from P3 to P5 and outline how we should manage that area’s tidal defences.
The flood risk management policy for this area is:
- P5 for tidal flooding
- P3 for fluvial flooding
A P5 policy means the Environment Agency and our partners need to take further action to reduce the risk of flooding, including upgrading the defences to cope with future sea level rise.
A P3 policy means we will maintain flood defences at their current level, accepting that the flood risk will increase. We need to involve communities to prepare for this flood risk.
The P3 policy applies in Twickenham because, in future:
- fluvial flood risk will increase with climate change
- we need to reduce the use of the Thames Barrier to manage fluvial flooding in this area, to ensure it can safely manage tidal risk
Find out more about flood risk management policies.
Local requirements: who needs to do what
Tidal flood defence owners
By 2050, tidal flood defence owners in this policy unit should:
- work with the council, developers and local infrastructure providers to adapt defences and achieve multiple benefits through proposed development
- work with the Environment Agency to raise defences where required
For further information read outcome 2: improving fixed flood defences.
Local councils
There is currently no riverside strategy for this area. By 2030, councils should work with communities to plan how their riverside will look in future.
Find out more about the riverside strategy approach.
Environment Agency
The Environment Agency will work with:
- Hounslow and Richmond Councils to identify areas that currently benefit from closing the Thames Barrier during fluvial events
- communities and partners to put alternative flood risk management measures in place for smaller fluvial events, before Thames Barrier operation changes in 2035 (smaller fluvial events are river flows of 600 cubic metres or less in combination with mean high water spring tides)
Thames Landscape Strategy team
The Thames Landscape Strategy Team based at Richmond Council will work with communities, councils, the Environment Agency and other partners to update the Thames Landscape Strategy.
This landscape vision for the river corridor will include a riverside strategy approach to upgrading tidal flood defences.