- The owner is required to maintain certain fundamental records, e.g.
water levels, spillway flows, leakages, etc. - The Panel Engineer nominated under 4 carries personal legal
responsibility for the statutory certificates and reports required of
him. - The Act includes provisions to ensure the safe discontinuance or
abandonment of a reservoir. - Statutory empanelment is an ‘ad hominem’appointment made on
the basis of relevant experience at an appropriately senior level.
Appointment is for five years and is renewable.
British legislation therefore provides for a two-tier system of surveil-
lance. Immediate responsibility for ongoing surveillance rests in the hands
of the Supervising Engineer, who is required to inspect at least annually,
with an appointed Panel Engineer responsible for periodic statutory
inspections. In the course of the latter, the Panel Engineer can make ‘rec-
ommendations in the interest of safety’ and may initiate such rigorous and
detailed investigations as are thought necessary, e.g. a reappraisal of spill-
way capacity etc. The principle of investing statutory responsibility for
inspections in the individual Panel Engineer is a most valuable feature of
the British approach, encouraging rapidity of response and flexibility.
7.5 Reservoir hazard and risk assessment
7.5.1 Hazard and risk assessmentClassification of reservoir hazard in terms of the scale of human and eco-
nomic loss to be anticipated in the event of a catastrophic dam failure is
increasingly common. At its simplest, hazard level is assessed and rated on
a descriptive categorization, e.g. ‘low’, ‘significant’ or ‘high’ (USBR, 1988).
An element of discretion may then be applied in defining the surveillance
régime to be applied to a specific dam. The limitations implicit in such
subjective appraisal and classification are evident.
A more rigorous assessment of reservoir hazard and associated risks
has the potential to significantly enhance the effectiveness of dam surveil-
lance programmes. In particular, reservoir risk assessment can be a valu-
able aid in ranking priorities for the allocation of limited resources
available for remedial work or for optimizing surveillance. Detailed and
more explicit hazard analyses can also be employed in contingency plan-
ning, embracing emergency scenarios for selected high-hazard reservoirs.
The latter may include the preparation of inundation maps (Section 7.5.2).
The nominal hazard level can be expressed adequately in terms of the
estimated risk of catastrophic breaching and/or the predicted worst-event