The Colorado River, an icon of the American West, is one of the most significant and important natural resources to the region. Originating in the Rocky Mountains it cascades down 14,000 feet as it traverses 1,450 miles through the Southwest and Mexico toward the Gulf of California. It drains a 246,000 square mile basin, an area roughly the size of France.
The Colorado River provides water to approximately 40 million people and irrigates nearly 4.5 million acres of farmland. Hydroelectric dams on the river have the capacity to produce more than 4,200 megawatts of electricity: enough to power between three and four million average U.S. homes. These dams rely on a consistent water supply to support hydroelectric generation, but prolonged drought and increased seasonal water variability have created new challenges for managers to effectively provide power as reservoir levels remain below "full pool."
This report has been constructed in such a way that considers impacts associated with reservoir declines in Lake Powell (the southern extent of the Upper Basin), and is intended to be a companion study to The Bathtub Ring, a similar report assessing impacts to Lake Mead (and the Lower Basin). Together, they comprehensively consider challenges across the entire Colorado River Basin.
With all this in mind, Looking Upstream has four broad objectives:
Determine contributing factors to the Upper Basin's water shortage vulnerability
Predict impacts to the recreational use of Lake Powell
Define operational and financial implications of reduced reservoir levels on hydropower generation at Glen Canyon Dam
Determine the impact to the environment and restoration programs associated with declining reservoir levels in Lake Powell
Key Findings Water supplies in Lake Powell are used to comply with Lower Colorado River Basin delivery requirements, generate hydropower, provide recreational opportunity, and maintain environmental health. Our findings demonstrate that declining reservoir levels could carry significant implications for each of these sectors, including higher riskto water supplies, an increased costof power for utilities served by Glen Canyon Dam, reduction in recreational visitation to Lake Powell, and the exacerbation of existing environmental challenges within the Colorado River system.
Factors contributing to water supply vulnerability are diverse
Recreational visitation could decline by more than a quarter
Hydropower firming purchase costs could increase up to a factor of ten
Declining reservoir levels compound the challenge of addressing widespread environmental impacts
This analysis of potential drought impacts to the Upper Basin is intended to provide quantitative and qualitative information that may inform long-term decision-making and regional planning. Should low lake levels become the norm, these findings are a glimpse into the conditions that will be faced across the broader Colorado River system.