Extreme heat intermittent lock operation: notice to boaters
Published 24 June 2026
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This publication is available at https://www.gov.uk/government/publications/extreme-heat-intermittent-lock-operation-notice-to-boaters/extreme-heat-intermittent-lock-operation-notice-to-boaters
When
Wednesday 24 June 2026 until further notice.
Where
All powered lock sites.
Details
Boaters are advised that the current UK heatwave is causing elevated temperatures across the River Thames. As a result, a number of hydraulic motors on lock control pedestals are reaching thermal trip limits.
This is leading to intermittent lock operation, with some locks alternating between powered and manual (hand-wound) operation.
These conditions are expected to continue for the duration of the heatwave.
During peak temperature periods (typically midday to late afternoon), the likelihood of equipment tripping is significantly increased. Locks are expected to return to more normal operation outside of the hottest parts of the day.
Locks currently reported as affected
- Osney Lock
- Sonning Lock
- Molesey Lock
- Whitchurch Lock
- Hurley Lock
- Hambleden Lock
- Clifton Lock
Additional locks may be affected at short notice.
Advice to river users
- avoid all but essential travel during this period
- allow extra time for your journey
- we advise against manually operating (hand-winding) locks during peak heat conditions
- where possible, plan travel outside peak heat hours
- take extra care when approaching and using locks
We appreciate your cooperation and patience while these conditions persist.