Leakage from poorly sealed joints
Publish date
02 September 2025
Case ID#
3114
Title
Leakage from poorly sealed joints
Nation
England
Regulator reference no.
303
Legal status
Statutory
Reservoir type
Impounding
Reservoir capacity
100,000 - 499,999m3
Year of construction
1800 - 1849
Main construction type
Earth fill embankment
Dam height
10 - 14.99 metres
Dam flood category
A
Hazard class
High-risk reservoir
Reservoir use
- Other
Owner type
Registered charity
Date & Time of incident
28 December 2006 - 12:00
Date incident closed
Observations that caused the incident to be declared
- Unexpected leakage or seepage from a known leakage point
Describe the incident
Increased leakage from a point two-thirds down the downstream face, adjacent to a spillway structure, was noted. The water level was lowered as a precaution and the leakage stopped. Regular surveillance of the toe area had not been carried out. Leakage was attributed to poorly-sealed joints in the spillway structure.
Supporting photos
Natural processes which initiated or contributed to the incident
- None
What were the main contributing factors to the incident occurring?
Dam factors
- Deterioration of materials
External factors
- None
Shortcomings
- Surveillance shortcoming
What was the root cause of the incident?
Impacts on the reservoir
- Internal erosion (adjacent to structures)
Supporting photos
Describe any human factors which influenced the incident
The reporter questioned the surveillance of the reservoir.
Describe any instrumentation at the reservoir and how this was used in warning of the incident or providing monitoring during the incident
No instrumentation at this dam.
Was instrumentation effective leading up to and during the incident?
Not Applicable
Describe any assistance by external parties and impacts on the downstream population
None
Summary of studies or investigations undertaken
Investigation suggested that leaking joints in the spillway structure were the source of the leak.