Science and Decision Making: Water Management and Tree‐Ring Data in the Western United States

American Water Resources Association (AWRA) | October 5th, 2009

Growing populations, limited resources, and sustained drought are placing increased pressure on already over‐allocated water supplies in the western United States, prom

Growing populations, limited resources, and sustained drought are placing increased pressure on already over‐allocated water supplies in the western United States, prompting some water managers to seek out and utilize new forms of climate data in their planning efforts. One source of information that is now being considered by water resource management is extended hydrologic records from tree‐ring data. Scientists with the Western Water Assessment (WWA) have been providing reconstructions of streamflow (i.e., paleoclimate data) to water managers in Colorado and other western states (Arizona, New Mexico, and Wyoming), and presenting technical workshops explaining the applications of tree‐ring data for water management for the past eight years. Little is known, however, about what has resulted from these engagements between scientists and water managers. Using in‐depth interviews and a survey questionnaire, we attempt to address this lack of information by examining the outcomes of the interactions between WWA scientists and western water managers to better understand how paleoclimate data has been translated to water resource management. This assessment includes an analysis of what prompts water managers to seek out tree‐ring data, how paleoclimate data are utilized by water managers in both quantitative and qualitative ways, and how tree‐ring data are interpreted in the context of organization mandates and histories. We situate this study within a framework that examines the coproduction of science and policy, where scientists and resource managers collectively define and examine research and planning needs, the activities of which are embedded within wider social and political contexts. These findings have broader applications for understanding science‐policy interactions related to climate and climate change in resource management, and point to the potential benefits of reflexive interactions of scientists and decision makers.

Science be Dammed: How Ignoring Inconvenient Science Drained the Colorado River

University of Arizona Press | November 26th, 2019

Science Be Dammed is an alarming reminder of the high stakes in the management—and perils in the mismanagement—of water in the western United States.  It seems decep

Science Be Dammed is an alarming reminder of the high stakes in the management—and perils in the mismanagement—of water in the western United States.  It seems deceptively simple: even when clear evidence was available that the Colorado River could not sustain ambitious dreaming and planning by decision-makers throughout the twentieth century, river planners and political operatives irresponsibly made the least sustainable and most dangerous long-term decisions. Arguing that the science of the early twentieth century can shed new light on the mistakes at the heart of the over-allocation of the Colorado River, authors Eric Kuhn and John Fleck delve into rarely reported early studies, showing that scientists warned as early as the 1920s that there was not enough water for the farms and cities boosters wanted to build. Contrary to a common myth that the authors of the Colorado River Compact did the best they could with limited information, Kuhn and Fleck show that development boosters selectively chose the information needed to support their dreams, ignoring inconvenient science that suggested a more cautious approach. Today water managers are struggling to come to terms with the mistakes of the past. Focused on both science and policy, Kuhn and Fleck unravel the tangled web that has constructed the current crisis. With key decisions being made now, including negotiations for rules governing how the Colorado River water will be used after 2026, Science Be Dammed offers a clear-eyed path forward by looking back. Understanding how mistakes were made is crucial to understanding our contemporary problems. Science Be Dammed offers important lessons in the age of climate change about the necessity of seeking out the best science to support the decisions we make.

Scoping Report for Post-2026 Colorado River Reservoir Operations Upper and Lower Colorado Basin Regions

U.S. Bureau of Reclamation (USBR) | October 19th, 2023

This scoping summary was prepared to document the scoping process for the Post-2026 Colorado River Reservoir Operations (Post-2026 process). As several important reservoi

This scoping summary was prepared to document the scoping process for the Post-2026 Colorado River Reservoir Operations (Post-2026 process). As several important reservoir and water management decisional documents and agreements that govern operation of Colorado River facilities and management of Colorado River water are scheduled to expire at the end of 2026, the Post-2026 process has been initiated to develop successor domestic Colorado River operational guidelines and strategies for Lake Powell and Lake Mead.

Seasonal Peak Snow Predictability Derived From Early-Season Snow in North America

American Geophysical Union (AGU) | September 12th, 2023

Early season snow observations show promise in predicting peak snow water equivalent in locations where large-scale ocean-atmosphere patterns similarly influence fall and

Early season snow observations show promise in predicting peak snow water equivalent in locations where large-scale ocean-atmosphere patterns similarly influence fall and winter conditions, and in northern maritime locations where winter temperatures are warm enough that rain on snow and midwinter melt occur.

Second Amended Delano-Earlimart Irrigation District Groundwater Sustainability Plan 2024

Delano-Earlimart Irrigation District Groundwater Sustainability Agency (DEID GSA) | July 1st, 2024

In January of 2020, the DEID GSA submitted its Groundwater Sustainability Plan (GSP) to the California Department of Water Resources (DWR). The GSP provided technical doc

In January of 2020, the DEID GSA submitted its Groundwater Sustainability Plan (GSP) to the California Department of Water Resources (DWR). The GSP provided technical documentation of the DEID Management Area’s existing sustainability, along with addressing the needs of the Earlimart Public Utility District and Richgrove Community Services District. The GSP outlined specific management actions that will be taken in accordance with the Sustainable Groundwater Management Act. DWR’s review of the Tule Subbasin, as a whole, resulted in an incomplete determination, to which the GSAs in the Tule Subbasin had 180 days to respond. The GSA’s in the Tule Subbasin provided revised GSPs on July 27, 2022, which DWR also determined were inadequate, causing the Tule Subbasin to transition to the oversight of the State Water Resources Control Board (SWRCB). The draft GSP found below includes updates to specifically address comments received from the SWRCB and their staff in anticipation of the Tule Subbasin probationary hearing on September 17, 2024. Comments on the 2nd amended GSP can be submitted to info@deid.org and will be accepted through August 18, 2024. Due to size, this file has been divided. Part 1, Part 2, Part 3, Part 4, Part 5, Part 6

Second Supplement to State Water Resources Board Bulletin No. 11, San Joaquin County Investigation, Basic Data, Calaveras Unit, 1955-56

California Department of Water Resources (DWR) | April 20th, 1957

Securing Color River Supplies - An Urban-Agriculture Partnership in the Palo Verde Valley

Metropolitan Water District of Southern California (MWD) | March 16th, 2022

Sensitivity of Mountain Hydroclimate Simulations in Variable-Resolution CESM to Microphysics and Horizontal Resolution

American Geophysical Union (AGU) | July 31st, 2018

Severe Sustained Drought Revisited: Managing the Colorado River System in Times of Water Shortage 25 Years Later — Part I

American Water Resources Association (AWRA) | September 20th, 2022

SGMA Alternative Groundwater Sustainability Plan Bridge Document for the Indio Subbasin

Coachella Valley Water District (CVWD) | December 29th, 2016