Mereway Weir Replacement

Closes 17 Jul 2021

Opened 17 Jul 2019


Updated on: 5 May 2020

Welcome to the Mereway project information webpage. Please click the link below to FAQs at the bottom of the page.


What is currently happening?

The new weir has been successfully installed and is now fixed in place and fully operational. The contractors have removed all their equipment from the area and the site is now open as it was before. The picture below shows the new weir being lifted into the River Crane channel at Mereway, and the completed installation underneath.

Future works

Construction of the fish pass through Mereway Nature Reserve is still being confirmed and we hope to start construction once a suitable option has been agreed.


We have replaced the weir on the River Crane located at the end of Mereway Road. Please see the location on the map below. The previous weir was at the end of its 30 year lifespan and it and its mechanisms had to be replaced.

Above: Location of Mereway Weir and picture of the previous structure

Alongside the completed weir replacement, we are also hoping to construct a fish pass, connecting the Duke of Northumberland's River and the River Crane. This will allow fish to access parts of the River Crane that have previously been limited or not available. This will attract further wildlife and create greater biodiversity in the surrounding areas. We are currently reviewing the possible designs. Please see potential locations below.

Above: Fish pass outline design in colour

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We are currently altering the above fish pass design due to high costs and projected impacts to the park. We will update this page with the latest designs as they are developed.

Who have we involved in our planning?

  • Richmond Borough Council
  • Friends of the River Crane (FORCE)
  • Friends of Kneller Gardens
  • Crane Valley Partnership


What is Mereway Weir? Mereway Weir is an automatic tilting weir on the River Crane, designed to maintain flows for the Duke of Northumberland's River and the River Crane.

What does it do? It keeps a steady flow into the River Crane and into the Duke of Northumberland and is a key flood defence asset for the Twickenham area.

Why has the weir been replaced? The previous weir was at the end of its lifespan, including the parts that operate it. A new weir and operating systems have been installed.

Who are the Environment Agency working with? We are working with Richmond Borough Council, Friends of the River Crane, Crane Valley Partnership and Friends of Kneller Gardens.

Why is a fish pass needed? A fish pass will be beneficial as the weir currently acts as a barrier to migrating fish from the Crane and Duke of Northumberland.

How will this benefit me? The weir protects over 500 residential properties from a high risk flood event. The weir continues this protection. The fish pass will act as another channel, linking the Duke of Northumberland and the River Crane.

Will I still be able to walk through Mereway Nature Reserve during the fish pass works? Yes, walking routes will still be accessible with diversion signs in place.

Will I still be able to drive through the nature reserve during the works? Yes, if there are any restrictions, these will be hours at a time rather than full days.

What trees will be removed? Some trees in the fish pass footprint may have to be removed.

How will we be notified about the works? Information will be available on this webpage so please check every so often. Other forms of communication are also planned:

  • Update letter drops for surrounding residents
  • Further posters around Mereway Nature Reserve
  • Social media

Contact Us

If you have a question about the project or would like further detail please email below:

Other Useful Links

Visit our website here to find out more about what you can do to reduce the impact of flooding on you and your property.

Sign up to flood warnings here.

Find out about your rights and responsibilities of owning a watercourse here.

If you have been flooded from a public sewer, please complete Thames Water's sewer flooding questionnaire on their website here and return it to them at the address on the form. 


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