If not for irrigation water, most of what is now the Southwest's crop growing area would be bone-dry desert. Instead, areas like the Maricopa-Stanfield Irrigation Drainage District (MSIDD) in central Arizona have become agricultural cornucopias producing fruits, vegetables, grains, animal feed, and cotton with water diverted from the Colorado River. Understanding the grower's water needs, and how the district's canal system can best fulfill them, is an ongoing project for the US Water Conservation Laboratory, Phoenix, Arizona.

In 1991, Allen R. Dedrick, the lab's director, proposed a collaborative agricultural management improvement program (MIP) to farmers and various state and federal farm service agency representatives in the area served by the MSIDD. Dedrick's goal was to improve agricultural sustainability and natural resource management by improving performance of irrigated agricultural systems in the district. The MIP called for "a level field where all the players could come together to identify opportunities for improvement, do the planning, and then make the changes in a coordinated way." The first part of the three-part MIP process was to analyze the current performance of existing irrigated systems to get a common, shared understanding of the situation. Next came defining opportunities and making plans for necessary change. Last was implementing plans for a coordinated effort to improve irrigation and overall resource management within the district.

One of the outcomes of the MIP was a report recognizing that much of the district had effectively become a cotton monoculture. The report stated that with the absence of crop rotation, cotton yields throughout the district had fallen. The water district's Board of Directors took steps to become more flexible in meeting farmer's needs. It reduced the winter water rate with the intent of improving the feasibility of planting the winter crops, like wheat and other small grains, in order to remedy this increasing problem of decreasing yield. As a result, increasing numbers of farmers rotated crops by planting winter wheat. The lowered water rates made this feasible for the growers.

For more information, please contact:

Allen R. Dedrick

e-mail: adedrick@uswcl.ars.gov

The MIPs original three year study ended in 1994, but continues on in the form of collaborative efforts between the Lab, the water districts, state and federal farm service agencies, and farmers. The MIP succeeded in providing a foundation of understanding and communication needed for people to work together. It also paved the way for partnerships involving tech transfer in the area of agricultural irrigation.

In an effort to make the irrigation of reclaimed farmland more efficient and with water conservation in mind, the US Water Conservation Laboratory, Phoenix, Arizona and Automata, Inc. of Grass Valley, California, recently signed a CRADA to develop hardware and software for economical and easy automation of irrigation canals. Currently, many large canals are operated manually from a control center. Very few large canals are operated with automatic controls such as microprocessor or computer controls, even though most of the technology is currently available. Also, most smaller secondary canals are operated manually, even though many water delivery regulation problems occur at this level. In general, canal operators are not comfortable with automatic controls because canal operations are complex and the previously available canal automation logic has often been too simplistic to handle the variety of operational needs. Further, available gate control hardware often is not "Intelligent" enough to implement sophisticated control logic, and is generally too expensive for smaller canals. ARS researchers are developing improved automation logic that can more fully satisfy operational needs. Automata, Inc. is developing low-cost control hardware that can use this logic.

For additional information on this or other CRADAs, please contact:

Albert J. Clemmens, USDA, ARS

US Water Conservation Laboratory

(515) 239-8279