​Floods and droughts continue to present dynamic challenges worldwide. Due to climate and landscape change, there is an increasing need to emphasize prevention, preparedness, mitigation and risk management to address these events and protect our safety, quality of life, economy and environment.

Structures within a floodplain are often severely damaged by the force of moving water, the pressure of standing water, or the debris and sediment associated with flooding. Likewise, while many municipal water supplies are capable of ensuring safe drinking water during flood events, private drinking wells can become contaminated by floodwaters—which tend to mobilize bacteria.

The plants and animals occupying floodplains, on the other hand, have evolved to cope with floods. In fact, many species rely on changing water levels as part of their life cycle. Frequent or intense flood events, however, can lead to erosion, destroyed breeding grounds and declining plant and animal communities.

Of varying duration and intensity, droughts present their own unique challenges.

These natural events have occurred throughout history and may last from several months to several years. Among many impacts, droughts often threaten farm production if sufficient rainfall or irrigation is not present to support crops and livestock. A shortage of water caused by drought can also affect a number of industries. For example, drought may significantly reduce the generation of electricity from hydropower, biomass or fossil fuel facilities. In addition, drought affects the availability of aquatic habitat, drinking water and food for wildlife.

The International Commission for the Protection of the Danube River notes, however, that droughts are not only a physical phenomenon, but an interplay between natural water availability and human demands for water supply. As the demand for water resources rises, the pressure on water grows and regions of the world become increasingly vulnerable during periods without rainfall.