Our reservoirs store the water which keeps the canals topped up throughout the year. We have 74 large reservoirs, some of the oldest in the country, and amongst the oldest of their type in the world. Without them, there wouldn’t be water for navigation or wildlife along our canals, or for those who enjoy the reservoirs themselves for sailing, fishing and other recreational activities.
We are carrying out a significant programme of investment in these reservoirs to make sure they stay resilient to climate change and comply with the strict legislation that applies to all large reservoirs. Over the past two years we have spent £57 million on reservoir works (a large proportion of the overall maintenance spend our charity has available), with spend forecast to average above £17 million per year for next five years.
Short-term challenges for long term benefit
The nature of the work required means that we have to reduce (‘draw down’) the water level in the reservoirs until the work is complete, meaning there will be less water than normal available to feed navigation. This means that we are more reliant than usual on rain throughout the year, and especially in summer when the canals are busier, to keep water levels topped up.
During 2025 we have significant construction works planned at over 10 reservoirs. Six of these feed well-used canals and drawing down the water for the works will mean there will be less water available. Impact will be minimised as far as possible and where feasible we schedule drawdown works towards the end of the summer.
While we do everything to ensure the navigations remain open, our legal obligations around reservoir safety and managing flood risk must take priority. We apologise for any inconvenience this causes boaters.
In 2025, the following reservoir works may affect navigation:
Leeds & Liverpool Canal
Major works to replace and enlarge the spillway at Rishton Reservoir are taking place throughout 2025, requiring a large drawdown that will affect water supply to the western end of the canal. Slipper Hill, Foulridge Lower and Foulridge Upper reservoirs are also drawn down for investigations ahead of expected major works. This means that the maximum capacity of the reservoirs feeding the canal will reduce to nearly 50% in the summer. To help ensure the water that is available lasts as long as possible, we are starting the peak boating season with restricted opening in hours in place at certain lock flights and are investigating other ways to preserve the available water for navigation.
More information about boating on the Leeds & Liverpool here.
Huddersfield Narrow and Rochdale canals
Major works to enlarge the spillway at Slaithwaite Reservoir are starting in 2025, reducing the amount of water available for the eastern part of the Huddersfield Narrow, while works at Sparth Reservoir over the 2024/25 winter have extended into spring. Diggle Reservoir will be drawn down at the end of the summer so that work can take place to move a drawoff valve that is currently situated 30m deep within the dam. Access, drawoff and spillway improvements are being carried out at Black Moss, March Haigh & Swellands reservoirs, but these works will not impact canal feed.
More information about boating on the Huddersfield Narrow here.
More information about boating on the Rochdale here.
Peak Forest and Macclesfield canals
The ongoing work to reinstate the water supply from Toddbrook Reservoir continues to impact the Peak Forest and Macclesfield. The works are due to be completed by spring 2026. Combs Reservoir will be drawn down late in 2025 for investigation works, with minimal additional impact expected.
More information about boating on the Peak Forest here.
More information about boating on the Macclesfield here.
Other reservoir works that are not expected to affect navigation:
Birmingham Canal Navigations: The clay core at Olton Reservoir has settled over time and needs to be raised to reinstate safe impounding levels. Drawdown in late summer to minimize canal impact.
Grand Union: Works are planned at Wilstone Reservoir to install a 1km-long sheet piled wall through the full depth of the embankment to reduce leakage. Scheduled for late in the 2025 season to minimise impact. Sulby and Welford reservoirs are being drawn down late in 2025 to enable investigation works ahead of a spillway enlargement at Welford in 2027.
Shropshire Union: Grouting masonry weirs to reduce leakage at Calf Heath Reservoir, and general maintenance at Gailey Upper and Gailey Lower reservoirs. A small drawdown with little navigational impact.
Please check this page for further details of how these works may affect cruising, and to see where water-saving restrictions are in place.
