USGS Report: Climate Change Will Reduce Groundwater In Lower Colorado River Basin

Nov 18, 2020

A new report from the U.S. Geological Survey says climate change will affect groundwater resources in both the Upper and Lower Colorado River Basin, but in different ways. KNAU’s Melissa Sevigny reports.

Credit John Grahame

The lower Colorado River Basin, which is primarily in Arizona, is projected to have as much as sixteen percent less groundwater infiltration by midcentury compared to the historical record. That’s because warming temperatures will increase evaporation while rain- and snowfall are expected to remain the same or decrease slightly.

But the river’s Upper Basin in parts of Utah, Wyoming, Colorado and New Mexico is projected to see precipitation rise by six percent by midcentury, increasing groundwater recharge in winter months. Groundwater is critical for sustaining desert ecosystems and supplies cities and farms in the Southwest.

The report’s findings come as climate scientists say 2020 is on track to be one of the warmest years in more than a century of recordkeeping.