Question

How is water introduced into rivers and streams?
short paragraph

Answer 1

Water enters rivers and streams mainly from precipitation—rain and snow—either directly into channels or as surface runoff that flows over the land. Seasonal sources like snowmelt and glacier melt add large pulses of water, while infiltrated precipitation becomes groundwater that discharges to streams as springs or baseflow, sustaining flow between storms. Tributaries contribute additional water, and human sources such as urban runoff, irrigation return flow, and wastewater can also feed rivers.