Irrigation is critical to U.S. agriculture. While just 16 percent
of all harvested cropland is irrigated, this acreage generates
nearly
half the value of all crops sold. Agriculture accounts for over
80 percent of water consumed in the U.S. Because of its large
share
of total consumption, agriculture is central to the challenge of
balancing water demands among alternative uses, including increasing
water demand for urban, industrial, and environmental uses.
Irrigation is particularly important for agriculture in the 17
Western States—even though only 30 percent of the harvested
cropland on all farms in the West is irrigated. On irrigated farms
in the
region, irrigation is used on over 80 percent of harvested cropland.
Irrigation systems are split evenly between gravity-based (such
as flooding furrows or entire fields) and more efficient pressure
systems (such as center-pivot sprinklers). Key to improving irrigation
efficiency are Federal, State, and local cost-share programs that
address farm water delivery systems (such as the lining of open-ditch
systems) and/or the adoption of more efficient technologies (such
as low-pressure sprinkler systems). About 13 percent of irrigated
farms in the West participated in public cost-share programs for
irrigation or drainage conservation improvements between 1994 and
1998.
These cost-share programs could be more effective if more carefully
targeted. Most irrigated farms are small (less than $250,000 in
annual farm sales), as are most farms that receive cost-share payments
to improve irrigation efficiency. But larger farms are by far the
heaviest users of irrigation water; the largest 10 percent of irrigated
farms in the West account for half of total farm water applied.
Cost-share programs that target larger farms would likely conserve
more water, making more water available to meet environmental and
other objectives, especially when integrated with water markets,
water banks, and conserved-water-rights programs. Water banks and
conserved-water-rights programs are relatively new State water
management
programs that either “bank” conserved agricultural
water for future use, usually in a reservoir, or share conserved
water
among alternative water-use interests.
A new ERS database on irrigation systems and the characteristics
of irrigated farms in the 17 Western States is a first step in
understanding
the impact of cost-share programs. It is based on data from USDA’s
1998 Farm and Ranch Irrigation Survey.
This article is drawn from...
Western
irrigated agriculture, a database summarizing
the farm-size characteristics of irrigated farms in the Western
United
States.