Threats to a Colorado river provisioning basin under coupled future climate and societal scenarios

Abstract

Clean, reliable supplies of water are critical to the sustainability and resilience of communities, including water needed for energy and food production, industry, drinking water, and other human and ecological needs. However, water infrastructure and management in the United States are largely optimized for historic conditions-designed and operated to respond to social needs, and past mean and extreme streamflow, which may no longer apply in the future. Temperature, precipitation, ecosystem dynamics, energy and food production, and social systems are all experiencing changes, which cumulatively affect the security of water supply. Here, we examine the impact of these changes in a provisioning basin in the arid Southwest, the San Juan River, which supplies water, food, and energy to the Colorado River and the Rio Grande. Our analysis applies a multi-model framework to examine future climate and water use scenarios. Results demonstrate that the San Juan River basin could experience significant disruptions to water deliveries (−12% to −48% for the drier models) and shortages that exceed manageable thresholds (53% to 73% of water in shorted years), potentially affecting both the local basin as well as other regions that receive water and energy from the San Juan. While water stress metrics vary across the scenarios, results indicate the need for government, industry, and communities to consider options for adapting to water supply shifts. These results raise important questions regarding the resilience of water resources in basins across the West under future scenarios and implications for energy, food, and other water supply needs.

Characterizing Drought Behavior in the Colorado River Basin Using Unsupervised Machine Learning

“…VIC was implemented and run as described in Bennett et al. (2018, 2019) and Solander et al. (2019), and is thus only briefly described herein.…”

“…The output from VIC captures the historical and future climate conditions (as physical indicators) for flow and drought conditions within the CRB. VIC was implemented and run as described in Bennett et al (2018Bennett et al ( , 2019 and Solander et al (2019), and is thus only briefly described herein. VIC is a spatially distributed, macroscale hydrologic model simulating the full water and energy balance while accounting for 1-D variably saturated infiltration through the vadose zone.…”

How resilient are waterways of the Asian Himalayas? Finding adaptive measures for future sustainability

“…For example, once the mighty Colorado river, which used to supply plentiful water and food resources to more than 40 million people in the seven western US states, is rapidly drying today (Milly & Dunne, 2020). Climate warming and prolonged droughts have led to a failure of the 20th century Colorado river commission accord, which was to fulfill the demand of water, energy and food resource supplies through irrigation and hydropower energy (Barnett & Pierce, 2009; Bennett et al, 2019). It is said that science was long ignored, which has led to the current crises in many urbanizing environments.…”

Spruce Beetle Outbreak Increases Streamflow From Snow‐Dominated Basins in Southwest Colorado, USA

“…Mortality rates of 50%–90% are common in areas affected by this particular outbreak (CSFS, 2019), including the headwaters of the economically and ecologically important Rio Grande river and large tributaries of the Colorado River. Consequently, streamflow impacts from beetle kill could have regional implications for water resources, flood management, and water managers' responses to climate change (Bennett et al., 2019; Booker et al., 2005; Hurd & Coonrod, 2007). Despite the outbreak's scale and potential implications, its impacts on streamflow remain unknown.…”