Replacing spillway flashboards and raising reservoirs with inflatable dams/gates

In recent years, inflatable dam/gate technology has greatly advanced and become a significant choice for replacing spillway flashboard systems and raising reservoirs. In the United States, over 200 inflatable dams/gates have been installed; of which approximately half were for replacing spillway flashboards or to increase reservoir storage. Inflatable dams/gates have also been used to replace steel gate systems such as vertical lift gates due to their inherently better reliability and safer operation, especially during a severe service condition. The two major types of inflatable dams/gates that have been used in the United States are: (1) Bridgestone Rubber Dams, and (2) Obermeyer Hydro Gates. Both of these inflatable dam/gate types are being installed in a wide variety of conditions, configurations, and environments. Very little has been published on the selection, design, reliability and performance of inflatable dams/gates, in part due to their fairly recent introduction to the dam engineering community. With over 2,000 inflatable dams in service worldwide, and over 10,000 years of collective service experience, there is now a basis for evaluating the general performance and application of this technology. The purpose of this paper is to provide a brief summary of the recent advances in inflatable dam/gate technology and to discuss the performance issues, product features and options available to those involved in selecting and designing inflatable dam/gate systems. The unique features and benefits of both the Bridgestone Rubber Dam and Obermeyer Hydro Gate systems will be compared and discussed. Specific design issues including options for sluicing floating debris, selecting air supply piping, and modifying existing spillway crests and abutments is presented. Recommendations for preparing contract documents are also discussed. 16 pp., 1 table, 10 figures, 7 references.