What are the “water cycle” and “water budget”?
The “water budget” refers to how much water enters the watershed and how much leaves – and where and how the water flows in or out (See water budget example for Ipswich R. Watershed). The water budget tracks the amount of water that moves through the hydrologic cycle or water cycle – the natural pathways of water into, through and out of the watershed. The natural “water budget” accounts for all the water entering the watershed, how it travels through the watershed or is stored, and all the water leaving the watershed: • Rainfall and snowfall (the average precipitation here is about 47″ a year) • Evaporation and “evapotranspiration” (“ET,” the water taken up and used by plants). Evapotranspiration returns about 50% of precipitation to the atmosphere, and is affected by climate (temperature, sunshine, wind) and vegetative cover • Water that infiltrates into the ground, replenishing groundwater and later providing baseflow • Runoff, or water that runs off the land into drainageways, stre
