What primarily influences hydrology on a site?

The primary influences on hydrology at a site are closely tied to factors that directly affect the movement and availability of water. Water table depth plays a crucial role in determining the availability of groundwater, which significantly impacts surface water levels, drainage, and overall hydrological behavior. Additionally, understanding flood risk is essential because it informs how water moves across a landscape during storm events and heavy precipitation. Flood risk also dictates how land-use planning can mitigate potential impacts on the hydrological cycle by addressing drainage systems, runoff, and water retention strategies.

While soil permeability, weather patterns, and vegetation all have important roles in hydrology as well, they do not encompass the broad implications that water table depth and flood risk have on site-specific hydrology. Soil permeability affects infiltration and drainage but is dependent on the water table to define how saturated the soil can be. Weather patterns certainly influence precipitation and evaporation rates, but they are transient and can be variable, while the water table and associated flood risks have long-term implications for hydrology. Similarly, while vegetation contributes to water retention and influences local ecosystems, the overarching factors of water movement and groundwater availability are more prominently dictated by water table depth and the potential for flooding in a given area.