New methods and criteria for designing spillways could reduce risks and costs significantly

Present methods for designing spillways are generally based on traditional criteria, which are not well adapted to present knowledge of actual risks. A review of facts and costs suggests that better adapted criteria and methods of design could reduce risks and costs. After an analysis of dam failures, the authors review present methods of designing spillways, and propose possibilities for reducing costs, while increasing discharge capacity. The suggested methods and design criteria could apply to both new dams and upgrades.