A flood is defined as a rising body of water and its overflowing onto normally dry land. This is typically slower in both onset and dissipation than a flash flood. In areas where this is to be expected annually, such as farmland, this isn't an issue. But when we put people and property in the way of rising waters, we need to attempt to mitigate floods through planning, code enforcement, and physical structures.
Although the Bureau of Reclamation has constructed the Jackson Lake Dam, and a joint effort between the Teton County Road and Levee department and the US Army Corps of Engineers maintains levees along the Snake and Gros Ventre Rivers, there is always the possibility of flood even without dam or levee failure.
The impacts for a flood are very similar to those for a flash flood. The main thing to keep in mind is that just as the onset of a flood is slow, so is the recession of the waters. This means that the recovery process can take much longer than that of a flash flood, which usually dissipates quickly.