What type of water is associated with hydrodynamic forces?

The correct answer is flowing water, which is associated with hydrodynamic forces. These forces arise from the movement of water, which can create significant impacts on structures, landscapes, and ecosystems. Unlike still water, which remains static and exerts pressure uniformly on any surface, flowing water generates dynamic effects due to its velocity and turbulence.

In scenarios involving flowing water, the hydrodynamic forces can vary greatly, depending on factors such as the speed and volume of the water. This includes aspects like erosion, sediment transport, and the potential for debris to be carried along, all of which can pose risks to flood-prone areas and need to be considered in floodplain management.

Still water does not produce these dynamic impacts because it lacks movement, thus does not exert the same types of forces. Saltwater and stormwater, while they can be involved in flooding situations, do not uniquely pertain to the concept of hydrodynamic forces as compared to general flowing water, which encompasses all types of moving water regardless of salinity or contamination.