Maintaining a hydroelectric dam requires a number of complex mechanical and electrical activities that must be performed on a regular and ongoing basis. Many of the necessary procedures are outlined by the U.S. Federal Energy Regulatory Commission (FERC) under the provisions of the Dam Safety Surveillance Monitoring Plan. The inspections and maintenance activities prescribed by this plan were designed by the National Hydropower Association in conjunction with dam operators and expert hydropower consultants. Proper maintenance and repair work is necessary not only to ensure a continued flow of power from the hydroelectric dam but also to protect the lives and property of those living in the vicinity of these massive structures.
Five General Categories of Inspections
Hydroelectric dam inspections are often divided into five separate categories:
- The initial dam inspection is comprehensive and encompasses all elements of the newly built hydroelectric dam. All equipment will be tested at the widest possible variances of tolerance levels to ensure that the dam will operate as intended under normal conditions.
- Periodic dam inspections incorporate visual inspections, equipment tests and a variety of other structural evaluations to record the current operating state of the dam.
- Routine dam inspections are conducted as part of the regular maintenance required by federal law or by plant management. These procedures can be scheduled on a recurring basis or can be included as part of other required maintenance tasks.
- Special inspections involve only one operating area or structural feature of the dam. Underwater inspections or specialized maintenance activities may be conducted as special inspections.
- Emergency inspections are required when the hydroelectric dam is not performing properly. While leaks, flooding and equipment failures are the most dramatic reasons for these maintenance events, emergency inspections can also be used to identify less critical failures in the hydroelectric dam environment.
Special and emergency inspections typically require the assistance of highly trained experts in the hydroelectric dam maintenance field. Many dams maintain these skilled inspectors and repair personnel as part of their regular staff; others may acquire outside help for these recurring tasks.
Safety Requirements for Hydroelectric Dam Inspections and Maintenance
Depending on the area to be inspected and maintained, facility managers must ensure that appropriate safety features are in place and are used properly. Catwalks and other walkways around pumping stations and inspection points must either be enclosed with railings or must be used only with the appropriate safety equipment. On the exterior of the dam, even stricter safety regulations apply. A fall from the exterior of the dam could be fatal; ensuring the correct anchorages and safety equipment for inspection and maintenance personnel is essential for hydroelectric dam facilities managers.
Fall Prevention Systems for Dam Safety
Fall protection equipment should be maintained and used properly. Most modern dams incorporate planned and integrated anchorage points as part of their original construction. Regular inspection of these anchorages is an important element of ongoing hydroelectric dam maintenance and safety procedures. Building managers should also schedule regular fall protection system inspections to ensure the safety of workers on site. Horizontal lifeline inspection procedures are especially important because these vital safety systems are often the last line of defense in protecting workers against falls. Before each use, each piece of fall protection equipment should be thoroughly inspected for signs of wear or damage. If such signs are present, the equipment should be replaced immediately.
Maintaining the safety of maintenance workers and inspection personnel throughout their duties is critical for the continued proper operation of hydroelectric dams. Providing these essential personnel with the right safety equipment both inside and outside the dam structure can provide added protection against serious injury for workers and reduced liability for dam owners and facility managers. By adhering to all federal regulations regarding maintenance and inspections for these complex structures, owners can protect workers and local residents from harm and ensure the proper working of these vital energy-producing facilities.