Waves in mountain reservoirs: analysis and methods for prevention

Abstract

The load of the wind and the impact of rapid gravitational movements in a reservoir generate waves whose nature and properties depend on the magnitude of the load and the water depth in the reservoir. In this paper we summarize the main existing scaling laws allowing assessing the resulting hydrodynamic effects, focusing not only on the amplitude of the waves, but also on their nature. Wind and slow gravitational movements produce sinusoidal waves while rapid gravitational movements produce steeper waves such as tsunamis. Given the limited extension of the mountain lakes, the produced waves rapidly meet the shores or the dam on which they generate a run-up whose amplitude depends on the characteristics of the incident wave and the slope of the shore. We have undertaken a theoretical analysis and collected several experimental data in order to show the similarities and the differences between the sinusoidal waves and the solitary waves in terms of run-up. We finally choose simple formulas and produce a chart enabling any engineer to make a first diagnosis.