The River Thames Scheme

The Statutory Consultation period for the River Thames Scheme runs for six weeks from 00:01 22 January 2024 to 23:59 4 March 2024.  

Designated a project of national significance, the scheme will include a new flood channel in two sections, passing though the boroughs of Runnymede and Spelthorne.  

To support the landscape-based approach of this flood alleviation scheme the surrounding areas of green infrastructure - green space - that run along the channel will provide better connections within and across the area and encourage more sustainable travel.  

Statutory Consultation gives local communities and key stakeholders the opportunity to ensure the final project design is informed and influenced by those who live, work, and use the area. This feedback will be considered alongside engineering parameters, costs, policy, and environmental factors, which stem from the scheme's goals. 

There are 11 in-person events across the scheme boundary and five virtual events.  

You can also view the non-technical summaries of the PEIR, flood modelling report, other environmental documents and map books free of charge at information points, in addition to being able to pick up printed copies of the Statutory Consultation brochures and feedback forms at our information points too. All documents can be viewed online. 

To find out more information on all the above go to their website. https://www.riverthamesscheme.org.uk/consultation

What is this scheme? 

The River Thames Scheme is an integrated scheme that delivers in a number of areas including reducing the risk of flooding to homes, businesses and infrastructure, in addition to improving access to quality green, open space, a more sustainable travel network and increasing biodiversity by creating a network of high-quality wildlife habitat. 

The River Thames Scheme will reduce fluvial (river) flood risk from Windsor to Teddington. The impact of the scheme varies by location and flood magnitude.

The Scheme consists of: 

A new river channel built in two sections - through Runnymede (between Egham Hythe and Chertsey) and through Spelthorne (between Littleton North lake and the Desborough Cut) 

Capacity increases around the Desborough Cut and the weirs at Sunbury, Molesey and Teddington 

Improving access to quality green, open space and connections with wildlife, in addition to supporting a more sustainable travel network 

Creating a network of high-quality habitats to achieve biodiversity gain. 

These River Thames Scheme will reduce the risk to thousands of homes and businesses, enhance the natural environment and facilitate sustainable and inclusive economic growth.   

Why do we need this scheme?

The River Thames Scheme covers part of the largest area of undefended, developed floodplain in England. Communities in the area have suffered major floods in the past. Just a few years ago in 2014, approximately 1,000 homes were flooded by the River Thames. This was far from the first time, with severe flooding also happening in 1947, 1968 and 2003.  

It's not just buildings and people which can be devastated from flooding. Major flooding in this area can cause severe disruption to the local and regional road network. It can impact drinking water supplies in the South-east and threaten the electricity network.  

The total economic damages for England and Wales from the winter 2013 to 2014 floods were estimated to be between £1 billion and £1.5 billion, with a best estimate of £1.3 billion. It is thought the damage could be twice as great by 2055, because of the impact of climate change.  

What are the different elements of the scheme? 

A major new piece of blue and green infrastructure, each element of the RTS will work together to deliver benefits for communities. A new flood channel will reduce the risk of flooding to homes, businesses, and infrastructure, while also providing habitat for wildlife and a new feature in the landscape for recreation. The channel will be flanked by new areas of public green open space, for recreation and spending time with nature. New footpaths and cycleways will run along the channel and through the new public spaces, linking different elements of the scheme with communities and providing better connections within and across the area. 

The new flood channel is effectively a bypass, like a new road bypass around a town. The flood channel provides a different route for flood water to travel but the volume of flow that passes downstream remains the same. With a road bypass, the new road eases congestion through the town centre but the number of cars on the existing roads either side of the town don't increase. 

When will this scheme be delivered? Why does it take so long? 

History of the Scheme

In December 2020, the government directed that due to its large scale, the River Thames Scheme should be treated as a project of national significance. These projects require a type of consent known as a 'Development Consent Order' (DCO). The DCO process removes the need to obtain many separate consents, including planning permission and is designed to be a quicker process than applying for these separately. 

The DCO must be granted before full funding is approved and construction can begin.

Early development of the scheme 

The case for the current River Thames Scheme started just over a decade ago, though the idea for a flood relief scheme along this section of the River Thames has been around for decades.  

The serious floods of 2014 provided the impetus for both the Environment Agency, Surrey County Council, and other partners to work together to reduce the risk of flooding.  

The River Thames Scheme will deliver the recommendations set out in the Lower Thames Flood Risk Management Strategy which was finalised after consultation with other public bodies, businesses, and residents in 2009. The strategy was approved by the Environment Agency Board in 2010 and accepted by Defra in 2011.  

During development of the Strategy, we looked at over 50 different options to manage flood risk between Egham and Teddington. The current approved proposal of a flood channel with associated capacity improvement works was found to be the most economic, technically viable and environmentally sound. 

Which areas of the River Thames will this project benefit? 

The River Thames Scheme (RTS) is designed to reduce flood risk from the River Thames between Egham and Shepperton. Generally, in most flood conditions, there is a reduction in flood levels with the River Thames Scheme, compared to existing conditions at all locations along the Thames.  

We have developed a river model to assess the impact of the scheme on flooding. The model also assesses the flows coming into the River Thames from other rivers such as the River Wey. This modelling has been used to test a wide range of flood magnitudes and conditions. It has confirmed that, with the scheme in place, there is no increase in peak river levels at any location or in any flood conditions compared to the situation without the River Thames Scheme.  

In most flood conditions modelling shows that there is a reduction in water levels. The River Thames Scheme flood channel does increase the flow passing downstream in the River Thames towards Kingston by up to 2%. However, the small increase in flows due to the flood channel is more than compensated for by the downstream mitigation measures such as the capacity improvements just downstream of Desborough Cut, at Sunbury weir, Molesey weir and Teddington weir. This is how the scheme is also able to provide some flood risk reduction benefit to communities in the lower section of the River Wey. 

For further information see our Flood Modelling report. Flood Modelling Report | River Thames Scheme

Why is the scheme now only two channels - with Datchet and Wraysbury no longer included? 

A third channel section from Datchet to Hythe End was previously included in the River Thames Scheme. The Royal Borough of Windsor and Maidenhead were unable to raise the funding required to deliver the channel section and as such this cannot be taken forward by the River Thames Scheme​ 

Removing this section of the channel does not change the existing flood risk in this area. ​ 

The Environment Agency continues to work with the Royal Borough of Windsor and Maidenhead to look at flood management solutions in the area more details can be found at Datchet to Hythe End​

When will work begin on building the channels? 

The River Thames Scheme represents a new landscape-based approach to creating healthier, more resilient, and more sustainable communities by reducing the risk of flooding and creating high quality natural environments. The new flood alleviation channel will reduce the flood risk to around 11,000 homes and 1,600 businesses in the area.  

The River Thames Scheme is in the pre application stage of its Development Consent Order (DCO) but the indicative timeline on the River Thames Scheme website suggests construction would likely take place between winter 2026 and the scheme being operational in winter 2030.   

Who is running this project? 

The project is being led by Surrey County Council and the Environment Agency. 

Along with other partners in the area: Runnymede Borough Council, Elmbridge Borough Council and Spelthorne Borough Council. It also includes Thames Regional Flood and Coastal Committee, Thames Water and two Local Enterprise Partnerships: Surrey Enterprise M3 & Thames Valley Berkshire.  The London boroughs of Richmond upon Thames and Kingston upon Thames are partners but are not responsible for funding the scheme.