A very interesting multi-hazard case study in Panama is reported on the website of the Smithsonian Tropical Research Institute. Heavy tropical storms in December 2010 resulted in increased groundwater levels, higher pore fluid pressures, and thus slope instability... meaning there was significant landslide activity. This landslide activity resulted in large amounts of sediment entering the water system, and causing the water treatment plant of Panama City to be closed down for almost a month. The impacts of this lack of clean drinking water can vary from increases in disease, illness and maybe even death. This interaction of several factors resulted in a number of negative impacts to Panama City.
A number of measures could be taken to prevent this sequence of events. Avoiding deforestation, in order to prevent erosion would be one measure to reduce the probability of landslides. Ensuring adequate drainage in slopes would also reduce the risk. This sequence of events should also inform and educate emergency planners - helping them understand the vulnerability of their water supply system. Back-up systems should be in place, bottled water stockpiled, and potentially boreholes drilled in key locations such as hospitals and schools.