When 40 million people and some of the most fruitful croplands in the world rely heavily on a single source of water, it seems only natural to want to know as much as possible about the source.

How will climate and hydrologic conditions, for example, affect the future productivity of that source? What are the trends? What can we expect in the near-term future? In the long run?

How effective have forecasting models been? And how might we improve them?

And, similarly, how can we best leverage our knowledge about the past – all the climate and hydrologic data we have collected over the years – to improve our capacity to anticipate the future?

Those are just some of the mysteries tackled in a recently published report – “Colorado River Basin Climate and Hydrology: State of the Science” – which has integrated nearly 800 peer-reviewed studies, agency reports and other sources to assess the state of the science and the technical methods relevant to water resources in the Colorado River Basin.

Produced through the Western Water Assessment team at the University of Colorado-Boulder, the report “aims to create a shared understanding of the physical setting and the latest data, tools, and research underpinning the management of Colorado River water resources.”

The Arizona Department of Water Resources is one of 12 funding partners and collaborators credited in the report.

"The report serves as a foundational knowledge base for water resources managers and researchers to help navigate the future of the Colorado River,” observed ADWR Director Tom Buschatzke.

“ADWR is proud to have contributed to the report, which was produced collaboratively by the water agencies of the Seven Basin States and the Bureau of Reclamation."

Among members of the Western water-science and water-management communities, the report has been received as perhaps the most comprehensive assessment ever of the state of the science of climate and hydrology in the Colorado River Basin. 

Terry Fulp, Regional Director of the Lower Colorado River Basin for the Bureau of Reclamation, observed that the report connects the dots “between data, methods, models, and projections of future conditions.”

“It will provide an invaluable foundation for future research, planning and management in the Basin,” said Fulp.

Brad Udall, Senior Water and Climate Research Scientist at the Colorado Water Center, Colorado State University, deems the report “by far the most comprehensive scientific report ever produced about the Southwest’s iconic river.”

And Colby Pellegrino, Director of Water Resources for the Southern Nevada Water Authority, meanwhile, hails its “extraordinary detail.”

It “lists a series of opportunities for using science and technology to help improve our understanding of current and future hydrologic conditions,” said Pellegrino.

The report could not have arrived at a better moment.

As the report notes, the river today is facing “unprecedented stresses,” the result of persistent dry conditions in the Southwest combined with the warming temperatures that impact the hydrology of the entire Colorado River Basin.

From the report:

“By synthesizing the state of the science in the Colorado River Basin regarding climate and hydrology, this report seeks to establish a broadly shared understanding that can guide the strategic integration of new research into practice.”