Water to Supply the Land: Irrigated Agriculture in the Colorado River Basin

Pacific Institute | May 9th, 2013

The Colorado River, recently named America’s most endangered river, supports millions of people in the American Southwest and northwest Mexico and helps irrigate millio

The Colorado River, recently named America’s most endangered river, supports millions of people in the American Southwest and northwest Mexico and helps irrigate millions of acres of land. Yet demands on the river already exceed the river’s average supply, a situation that is projected to get worse in coming years as climate change reduces runoff at the same time that fast-growing southwest cities demand more water. Irrigated agriculture currently consumes more than 70% of the water supply within the Colorado River basin, making it critical for more efficient water use. For the first time, new research from the Pacific Institute describes the extent of irrigated agriculture throughout the seven Colorado River basin states and two additional states in Mexico, the types of crops grown, and the amount of water used to grow these crops. In addition, the new report – Water to Supply the Land: Irrigated Agriculture in the Colorado River Basin – compares several agricultural management scenarios and the potential water savings and costs associated with each. Importantly, none of the scenarios remove agricultural land from production. More than 90% of pasture and cropland in the 256,000-square-mile Colorado River Basin requires irrigation, with about 60% of the irrigated acreage devoted to pasture, alfalfa, and other forage crops used to feed cattle and horses. These forage crops consume about 5 million acre-feet per year, equivalent to a third of the river’s annual flow. Employing innovative irrigation techniques more strategically and in more places – techniques that many farmers are already using – can help ensure agriculture in the basin states continues in the face of rising demand and climate change’s projected impact on supply. Modeling a series of agricultural water management conservation strategies – including regulated deficit irrigation, crop shifting, and advanced irrigation technologies – the Pacific Institute compared potential water savings and costs associated with individual scenarios. The analysis shows considerable water savings are possible. For example, almost a million acre-feet of water may be generated by irrigating alfalfa less often (a practice known as “regulated deficit irrigation”) throughout the basin in the U.S., at an estimated base cost of approximately $81 per acre-foot. Other scenarios, such as shifting to less water-intensive crops, also yield impressive water savings with relatively low costs and without reducing the total amount of irrigated acreage in the basin. For example, replacing about 10% of the basin’s irrigated alfalfa acreage with cotton and wheat could save about 250,000 acre-feet of consumptive water use each year, with estimated base costs of less than $40 per acre-foot. Total reductions in water withdrawals and applied water would be even greater.

Water transfers (Resource Management Strategy)

California Department of Water Resources (DWR) | July 29th, 2016

The California Water Code (CWC) defines a water transfer as a temporary or long-term change in the point of diversion, place of use, or purpose of use due to a transfer,

The California Water Code (CWC) defines a water transfer as a temporary or long-term change in the point of diversion, place of use, or purpose of use due to a transfer, sale, lease, or exchange of water or water rights. Temporary water transfers have a duration of one year or less (CWC Section 1725). Long-term water transfers have a duration of more than one year (CWC Section 1728). Transfers can be between water districts that are neighboring or across the state, provided there is a means to convey or store the water. A water transfer can be a temporary or permanent sale of water or a water right by the water right holder, a lease of the right to use water from the water right holder, or a sale or lease of a contractual right to water supply. Water transfers can also take the form of long-term contracts for the purpose of improving long-term supply reliability.

Water Transfers Brochure: Guidance and Information for Water Transfers

U.S. Bureau of Reclamation (USBR) | February 13th, 2014

The Bureau of Reclamation (Reclamation) developed the Water Transfers Brochure (Brochure) to assist water purveyors in the preparation of water transfer and Warren Act pr

The Bureau of Reclamation (Reclamation) developed the Water Transfers Brochure (Brochure) to assist water purveyors in the preparation of water transfer and Warren Act proposals and documents. It is a “work in progress” that will be refined as necessary to adapt to changing circumstances or improve its utility, this Brochure provides general guidance on communicating, preparing, and submitting a proposal, as well as presenting estimated timelines for associated requirements, actions, and approvals. This Brochure is meant to increase the efficiency of the logistical and administrative processes that Reclamation and the transfer parties control and to further the goal of timely facilitation of water transfers that require conveyance through Central Valley Project (CVP) facilities or otherwise require Reclamation approval. This Brochure provides a framework and certain details of the processes; however, dependent on the transfer or Warren Act proposal, additional coordination or steps may be necessary to facilitate approval of a proposed action. Reclamation encourages all water purveyors to work closely with their designated Reclamation representative in developing transfer, exchange, and/or Warren Act proposals.

Water Transfers in Water Resource Systems

American Society of Civil Engineers (ASCE) | March 1st, 1995

Water transfers are a common component of many regional water systems and are being increasingly considered for meeting growing water demands and for managing the impacts

Water transfers are a common component of many regional water systems and are being increasingly considered for meeting growing water demands and for managing the impacts of drought.  Water transfers can take many forms and can serve a number of different purposes in the planning and operation of water resource systems. However, to be successful, water transfers must be carefully integrated with traditional water supply augmentation and demand management measures.  This integration requires increased cooperation among different water use sectors and resolution of numerous technical and institutional issues, including impacts to third parties.  This paper identifies the many forms that water transfers can take, some of the benefits they can generate, and the difficulties and constraints which must be overcome in their implementation.

Water Use Across the Conterminous United States, Water Years 2010–20, Chapter D of U.S. Geological Survey Integrated Water Availability Assessment—2010–20

U.S. Geological Survey (USGS) | January 15th, 2025

Key Points An estimated average of 223,594 million gallons per day (Mgal/d; 26,179 million cubic meters per month [Mm3/mo]) were withdrawn from freshwater sources fo

Key Points An estimated average of 223,594 million gallons per day (Mgal/d; 26,179 million cubic meters per month [Mm3/mo]) were withdrawn from freshwater sources for human use for crop irrigation, public supply, and thermoelectric power across the conterminous United States (CONUS) during water years 2010–20. Including saline water, withdrawals were 244,817 Mgal/d (28,677 Mm3/mo). Average withdrawals and consumptive use (1) for CONUS crop irrigation during water years 2010–20 were 105,497 and 75,698 Mgal/d, respectively; (2) for public supply were 35,440 and 4,219 Mgal/d, respectively; and (3) for thermoelectric power from fresh water were 82,656 Mgal/d and 2,904 Mgal/d, respectively. Across the CONUS, the source of water—whether groundwater, surface water, public supply, reclaimed wastewater, or a combination thereof—typically depends on the availability of these sources and on the category of use. The water-use categories of industrial, self-supplied domestic, mining, livestock, and aquaculture together accounted for 10 percent of water withdrawals in the United States in 2015. Although a small proportion nationally, these water-use categories can be locally important. Companion chapters: U.S. Geological Survey Integrated Water Availability Assessment—2010–20, Chapter A Water Supply in the Conterminous United States, Alaska, Hawaii, and Puerto Rico, Water Years 2010–20, Chapter B Status of Water-Quality Conditions in the United States, 2010–20, Chapter C  Climate Change and Future Water Availability in the United States, Chapter E  Integrated Water Availability in the Conterminous United States, 2010–20, Chapter F 

Water Use by Urban Lawns and Trees in Los Angeles

University of California, Los Angeles (UCLA) | July 24th, 2017

Water Use in California

Public Policy Institute of California (PPIC) | April 19th, 2023

Water Use Trends in the United States

Pacific Institute | April 15th, 2015

Total water use in the United States declined markedly in the five-year period ending in 2010, according to data released from the United States Geological Survey (USGS).

Total water use in the United States declined markedly in the five-year period ending in 2010, according to data released from the United States Geological Survey (USGS). Total water use in the U.S. is now lower than it was in 1970, despite continued population and economic growth. The Pacific Institute analyzes and explains the factors contributing to this positive news, while including a cautionary note, in a new report released today. The Pacific Institute, an internationally-renowned independent think tank focused on water issues, reviewed the USGS’ most recent data collection, along with historical, national water use data. Remarkably, water use in 2010 was down in all sectors – agriculture, municipal and industrial, and thermoelectric power. The Pacific Institute’s new report shows that reductions in water use for thermoelectric power generation – the single largest use of water in the U.S. – accounted for nearly two-thirds of the reduction in water use between 2005 and 2010. This represents an important reversal of a 25-year trend of increasing water use to produce energy. In addition, water use for agricultural irrigation was at its lowest level in more than 40 years, even while the number of acres irrigated increased. The report shows that, from 2005 – 2010, per capita water use in the United States declined 17% to 1,200 gallons per person per day, levels not seen since the 1940s and the single largest decline in any five-year period. Moreover, the economic productivity of water – which measures the dollars of Gross Domestic Product per unit of water used – increased by 20% during that period to an all-time high of $11.49 per 100 gallons, an indication that the U.S. produces far more wealth, with less water than at any time in the past. While these trends reveal overall improvements in the management of our nation’s water , the current pace of its use is still not sustainable. Continued population and economic growth, along with the impacts of climate change, will strain the amount of water available for a thirsty nation. “The data suggest that national water use is moving in the right direction, but this doesn’t mean the work is done or that existing efforts are sufficient,” states lead author Kristina Donnelly. “We must continue to improve water use efficiency in our homes, businesses, and on America’s farms in order to ensure a sustainable water supply for the nation.”

Water Wasted to the Sea?

University of California, Davis (UC Davis) | July 15th, 2017

Water Year 2017: What a Difference a Year Makes

California Department of Water Resources (DWR) | October 3rd, 2022

The very wet conditions of 2017 gave many parts of the state access to excess surface waters for both planned and impromptu groundwater recharge, and fall 2017 groundwate

The very wet conditions of 2017 gave many parts of the state access to excess surface waters for both planned and impromptu groundwater recharge, and fall 2017 groundwater level data (not available until the end of the calendar year) should show the effects of the substantial recharge water available