Mereway Weir Replacement

Closes 1 Apr 2022

Opened 17 Jul 2019


Updated on: 11 February 2021

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


What is currently happening?

We are planning to install the fish pass between the Duke of Northumberland and the River Crane this year. This will be built next to the recently refurbished Mereway Weir, in Mereway Nature Reserve. Please see the map below for reference.

We will be in the area from 17-24 February 2021 clearing areas in Mereway Nature Reserve to prepare for the working area and installation of the fish pass. You may see our contractors here during this time. Please note they will only be working on weekdays.


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 updated structure

Alongside the completed weir replacement, we will be constructing a fish pass, connecting the Duke of Northumberland 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. Please see the landscape design below.

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, increasing the amount of fish seen upstream.

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 if needed.

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 and working area 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. 


  • Recreational and commercial river users
  • Fishing clubs and representative associations
  • Members of the public with an interest in the river, the species and conservation
  • Businesses
  • Charities
  • Statutory organisations
  • NGOs
  • Members of the public
  • Elected representatives, including MPs
  • Local councils
  • Academics
  • All water abstractors
  • Environment Agency customers
  • Local authorities
  • District and parish councils
  • Environmental bodies
  • Land owners
  • RFCCs
  • Elected representatives, including MPs
  • Water companies
  • Members of the public
  • Recreational and commercial river users
  • Community groups
  • Flood action groups
  • Environment Agency colleagues
  • Lead Local Flood Authorities
  • Local Risk Management Authorities
  • Flood Resilience Forums
  • Members of the public
  • Town and parish councils
  • Regional Flood and Coastal Committees
  • Internal Drainage Boards
  • Engagement specialists/operational staff in Natural Resources Wales, local authorities and other risk management authorities


  • Flood management
  • Water resources
  • Water quality
  • Habitats and wildlife