Colorado River Aqueduct Recording Project 1998

National Park Service (NPS) | December 15th, 1988

The Colorado River Aqueduct Recording Project is part of the Historic American Engineering Record (HAER), a long-range program that documents historically-significant eng

The Colorado River Aqueduct Recording Project is part of the Historic American Engineering Record (HAER), a long-range program that documents historically-significant engineering, industrial, and maritime sites In the United States. The HAER program is administered by the Historic American Buildings Survey / Historic American Engineering Record (HABS/HAER) Division of the National Park Service. U.S. Department of the Interior. The recording project was co-sponsored during the summer of 1998 by HABS/HAER under the general direction of E. Blaine Oliver, Chief; and by the Metropolitan Water District of Southern California, Gary M. Snyder, Chief Engineer, and Wally M. Lieu, Assistant Chief Engineer. The measured drawings, historical report, and photographs were prepared under the direction of Eric N. DeLony, Chief of HAER, The recording team included Supervisory Architect Andrew Johnston (University of California, Berkeley) and architects Chrysti Chun (Illinois Institute of Technology), Imola Klrlzsa'n (ICOMOS, Romania), Sydney Mainster (University of California, Berkeley), Elizabeth Mllnarik (University of Illinois, Urbana-Champaign), and Nina Shatberashvili (ICOMOS, Republic of Georgia); Project Historian J. Philip Gruen (University of California, Berkeley); and photographer Jet Lowe (Washington, D. C.) Additional drawings were provided by architects Christopher B. Brown (University of Washington) and Adrim Maksay (Transylvania Trust Foundation, Romania). Engineer Allien Whitsett (Metropolitan Water District of Southern California) provided consultation and advice. Devon Kobayashi (Metropolitan Water District of Southern California) served as HAER liaison.

Colorado River Aqueduct Route Selected for Metropolitan Water District Requires Pumping

Civil Engineering | February 10th, 1931

Colorado River Aqueduct, Historic American Engineering Record

National Park Service (NPS) | August 1st, 1998

The Colorado River Aqueduct pumps water from the Colorado River through, over, and across mountains and desert in a 242- mile-longmarchtothecoastalplainofSouthernCaliforn

The Colorado River Aqueduct pumps water from the Colorado River through, over, and across mountains and desert in a 242- mile-longmarchtothecoastalplainofSouthernCalifornia. When completed,itwasoneofthelongestwater-conveyancefacilitiesin the world. The aqueduct includes power lines, tunnels, siphons, covered conduits, open canals, dams, reservoirs, and five pumping plants, involving ingenious engineering solutions and newly- introduced construction equipment. The project also employed over 35,000 people during its eight-year span and as many as 10,000 at one time, making it southern California's single-largest work opportunity during the Great Depression. In 1995, the Colorado River Aqueduct was named a National Historic Civil Engineering Landmark by the American Society of Civil Engineers. Today, it is the major water supply for urban and suburban southern California.

Colorado River Basin August 2022 24-Month Study

U.S. Bureau of Reclamation (USBR) | August 16th, 2022

Colorado River Basin Climate and Hydrology State of the Science

University of Colorado, Boulder | April 15th, 2020

The Colorado River Basin currently faces unprecedented stresses. Persistent dry conditions since 2000, along with the increasing recognition that warming temperatures are

The Colorado River Basin currently faces unprecedented stresses. Persistent dry conditions since 2000, along with the increasing recognition that warming temperatures are impacting the hydrology of the basin, have led to great concerns about the long-term reliability of basin water supplies. With ever-higher stakes for water resource planning and decision making, an even greater emphasis is placed on the tools that support those activities, notably Reclamation’s operations and planning models and similar models used at other agencies. The usefulness of these system models depends on many types of datasets and forecasts that serve as inputs to them, as well as the research and scientific understanding underpinning this complex chain of data and models. The development and refinement of the different links of the chain necessarily involves researchers, forecasters, and water managers. New research efforts have advanced our understanding of the hydroclimate of the basin and how key hydroclimate processes, variability, and changes can be captured in data and models. This rapid expansion of the scientific knowledge base, and the increasing complexity of the data and models used to operationalize that knowledge, parallel the growing uncertainties about the future climate and hydrology. Accordingly, basin stakeholders have recognized the importance of reassessing the scientific and technical basis for management and planning.

Colorado River Basin Environmental Transfers Scorecard

Stanford University | March 16th, 2017

The Colorado River and its tributaries support more than 35 million people and irrigate more than four million acres of farmland. At the same time, the river supports 30

The Colorado River and its tributaries support more than 35 million people and irrigate more than four million acres of farmland. At the same time, the river supports 30 fish species found nowhere else on earth and inspires millions of visitors and residents alike with its sheer beauty. However, growing water scarcity caused by increased water use, hydrologic variability and climate change loom over all the Colorado River provides. Click here for follow-up report.

Colorado River Basin Reservoir Storage: where do we stand?

John Fleck | June 1st, 2025

Colorado River Basin Ten Tribes Partnership Tribal Water Study

U.S. Bureau of Reclamation (USBR) | December 13th, 2018

The Colorado River Basin Tribes Partnership (a.k.a. Ten Tribes Partnership) and the Bureau of Reclamation (Reclamation) initially undertook the Colorado River Basin Triba

The Colorado River Basin Tribes Partnership (a.k.a. Ten Tribes Partnership) and the Bureau of Reclamation (Reclamation) initially undertook the Colorado River Basin Tribal Water Study to augment the data produced for the Colorado River Basin Supply and Demand Study of 2012. With five tribes in the Upper Basin and five tribes in the Lower Basin, and between us, holding rights to more than 2.8 million acre-feet per year of water from the Colorado River and its tributaries, the Ten Tribes Partnership was uniquely positioned to explore these issues. However, in so doing, we learned that the effort would also serve to facilitate a broader and, we hope, a better understanding of the role tribal water plays, and will play, in the Colorado River Basin over the coming decades. In addition to producing technical information, the Tribes had other goals. First, we wanted to better understand how, at present, each of our individual water use scenarios fits into the overall scheme of Colorado River Basin management. Second, we wanted to know how future development of tribal water resources will alter Basin operations and affect other water users who are now using water to which a tribe may hold legal title, but which the title-holding tribe has not yet developed for its own use. Finally, we wanted to assess – to the extent present information allows – the role future development of tribal water rights will have on Basin operations. Along the way, we encountered data gaps, modeling limitations, and uncertainties, but nonetheless, with the support of Reclamation, we managed to address those issues sufficiently that we now provide this Report. If there is a ‘take-away’ that was surprising, it is that, even under the most favorable of circumstances for rapid tribal water development, the amount of water that will be used by the Tribes is dramatically overshadowed by the effect of climatic conditions on the overall supply of water in the Basin. Nature is still in charge. Challenges remain, but opportunities are in the offing. We hope this Report informs, resolves some uncertainty about how tribes perceive the future for their water uses, and establishes a baseline for discussions and development of relationships among tribes, states, the federal government, water managers, and water users throughout the Basin.

Colorado River Compact, 1922

U.S. Bureau of Reclamation (USBR) | November 24th, 1922

Colorado River Drought Contingency Plan Authorization

United States Congress | April 16th, 2019

Authorized Drought Contingency Plans (DCPs) for the Upper and Lower Colorado River Basins, which required reduced Lower Basin deliveries beyond previous curtailment plans

Authorized Drought Contingency Plans (DCPs) for the Upper and Lower Colorado River Basins, which required reduced Lower Basin deliveries beyond previous curtailment plans at specified Lake Mead storage levels, committed Reclamation to additional water conservation efforts, and put in place plans to coordinate Upper Basin operations to enhance Lake Powell storage levels and prevent the loss of hydropower generation.