Coping With Megadrought in the Colorado River Basin

Introduction & Welcome

Speaker: Elizabeth Weight, NOAA's National Integrated Drought Information System (NIDIS), Cooperative Institute for Research in Environmental Sciences (CIRES)

• Introduction of today's speaker: John Fleck, Director of the University of New Mexico's Water Resources Program
• The National Integrated Drought Information System (NIDIS) was created by Congressional law in 2006 with a mandate to help the nation prepare for, mitigate, and respond to the effects of drought.
  • Learn more about NIDIS and the eight regional Drought Early Warning Systems.

Coping with Megadrought in the Colorado River Basin

Speaker: John Fleck, University of New Mexico Water Resources Program

• The Colorado River Basin spans two nations, 7 U.S. states, 29 tribal nations, 5+ million acres of irrigated farmland, and 40 million people.
• A dry 2019 summer and fall meant low soil moisture going into the winter of 2019–2020.
• A 2020 study led by Columbia University examines the Southwest megadrought:
  • The first two decades of the 21st century have been the driest such period since the 1500s, as measured by summer soil moisture proxies.
  • The researchers concluded that anthropogenic warming is responsible for around half of that dryness.
• Reservoir storage in the Colorado River Basin:
  • Hoover Dam, creating Lake Mead, was built in the 1930s. Glen Canyon Dam, creating Lake Powell, was built in the 1960s.
  • Reservoirs built over the 21st century can hold 5 times the Colorado's annual flow.
  • They began the 21st century nearly full. Now they are not.
• So what do we do next?
  • More municipal water conservation
  • A growing urban-rural social contract
  • Better rules about sharing what remains as we continue to see shrinking supplies

Questions & Answers

Moderator: Elizabeth Weight, NOAA/NIDIS, CIRES