A new study, led by assistant professor Lijing Wang, investigates how snowmelt and subsurface water sustain headwater streams in mountain regions through late summer. Using field measurements and a modeling framework, the team showed that evergreen forests delay snowmelt by one to two weeks and gradually release water, buffering streamflow over longer periods. They also discovered a second seasonal peak in groundwater levels caused by subsurface geological transitions that temporarily store and later release snowmelt. The study highlights that subsurface permeability controls how stored water feeds streams, especially late in the season. These insights improve hydrologic models and may improve efforts to predict water availability amid climate change.
