The five yearly inspection of a dam is something tackled as a piece of methodical detective work according to Bridle. Having studied all the documentation available, including earlier reports, Bridle likes to quietly walk around taking everything in and photographing as many things as possible.
One thing he tries to avoid is being shown round by the supervising engineer or someone with an ongoing responsibility for the structure. Bridle does not like being guided closely since the inspection is essentially for discovering something unusual. Is this of real significance? is the question at the front of his mind.
Upstream and, very careful, downstream examinations of the structure or embankment are followed by a close check of the interior. This will involve looking at any recording devices, and entering confined spaces such as galleries and shafts within a dam.
Private owners are the bane of reservoir inspectors. Of Britains 2,500 large dams a significant number were built in the heyday of country houses to form ornamental lakes. These constructions tend to be owned by people or organisations with relatively small resources and no technical expertise of their own.
The embankments age and their situations means there is a relatively high risk. But maintenance is often minimal and there is no cash available should any expensive repairs be needed.