Dam Operation & Maintenance – Pay a Little Now or Pay Dearly Later

Following the Kaloko Dam failure on the Island of Kauai, the State of Hawaii, Department of Land and Natural Resources, Dam Safety Division, initiated Phase I Investigations of all regulated dams within the state. All 135 Significant and High Hazard dams on the islands of Oahu, Maui, Kauai, Hawaii, and Molokai were inspected. Existing documents including design drawings, previous inspection reports, computations, specifications, and design reports were also reviewed to evaluate the overall compliance of each dam with current design standards and to identify potential failure modes. The authors inspected and developed Phase I Investigation reports for the 16 regulated significant and high hazard dams on the Island of Oahu. Of particular note from the Phase I Investigations was the wide range of operating and maintenance standards encountered at the dams. Operating and maintenance practices ranged from a very formal and aggressive program with the dam maintained in near pristine condition, to complete abandonment of the dam with no maintenance activities performed for over 30 years. The contrast between the dams with good and poor maintenance practices, and the consequences and costs of deferred maintenance were readily apparent, and provide a compelling case for dam owners to develop and follow a formal operation and maintenance plan for their dam. This paper provides a discussion of the importance of developing and following a formal dam operation and maintenance plan. Findings from the recent Phase I inspections of the 16 dams on the island of Oahu and other dams inspected by the authors are used as examples to illustrate the benefits of regular maintenance and the consequences and costs of deferred maintenance. Industry standards of practice for operating and maintaining dams along with recommendations for developing an effective operation and maintenance plan are also presented. Failure modes at dams associated with deferred maintenance are described along with examples of how effective operation and maintenance programs have contributed to the early detection and aversion of dam failures. [Also presented at Dam Safety 2009]