Author
Evett, Steven - Steve | |
CARMAN, DENNIS - NRCS-LITTLE ROCK, AR | |
Bucks, Dale |
Submitted to: USCID International Conference
Publication Type: Proceedings Publication Acceptance Date: 5/12/2003 Publication Date: 5/30/2003 Citation: EVETT, S.R., CARMAN, D., BUCKS, D.A. EXPANSION OF IRRIGATION IN THE MID SOUTH UNITED STATES: WATER ALLOCATION AND RESEARCH ISSUES. USCID INTERNATIONAL CONFERENCE. 2003. P. 247-260. Interpretive Summary: The USDA Natural Resources Conservation Service and Agricultural Research Service cooperated on a study of the expansion of irrigated lands in the Lower Mississippi River Valley (LMRV), and the major research needs to improve efficiency of water use, water quality, and to decrease environmental impact. Irrigated lands in the LMRV surpassed 6.5 million acres in 1997 and are increasing at a rate of 189,000 acres per year. Arkansas is experiencing the most rapid increase in irrigation and had more than 4 million acres under irrigation in 1997, making it the fourth ranking irrigated state in the nation. Annual farm gate receipts in the four most heavily irrigated LMRV states, Arkansas, Missouri, Mississippi, and Louisiana, exceed $8 billion. Despite annual rainfall >40 inches, periodic summertime drought makes irrigation necessary to avoid crop failure. Little of the irrigated land is within organized irrigation districts. Rather, irrigation is mainly from wells on individual farm tracts. The increase in groundwater pumping has resulted in aquifer depletion, particularly in eastern Arkansas, resulting in a need for surface water diversion to replace well pumping. Currently, ten irrigation projects are in the planning or construction phases in Arkansas. However, lack of scientific data about water quality, management efficiency, and environmental impacts in humid-region irrigation schemes is a major impediment to project design and public acceptance, not only in Arkansas but in other Delta states. Research needed to improve this state of affairs is listed. Technical Abstract: Irrigated lands in the Lower Mississippi River Valley (LMRV) surpassed 6.5 million acres (2.6 million ha) in 1997 and are increasing at a rate of 189,000 acres (77,000 ha) per y. Arkansas is experiencing the most rapid increase in irrigation and had >4 million acres (1.62 million ha) under irrigation in 1997, making it the fourth ranking irrigated state. Annual farm gate receipts in the four most heavily irrigated LMRV states, Arkansas, Missouri, Mississippi, and Louisiana, exceed $8 billion. Despite annual rainfall >40 inches (100 cm), periodic summertime drought makes irrigation necessary to avoid crop failure. Little of the irrigated lands is within organized irrigation districts. Rather, irrigation is mainly from wells on individual farm tracts. The increase in groundwater pumping has resulted in aquifer depletion, particularly in eastern Arkansas, resulting in a need for surface water diversion to replace well pumping. Currently, ten irrigation projects are in the planning or construction phases in Arkansas. However, lack of scientific data about water quality, management efficiency, and environmental impacts in humid region irrigation schemes is a major impediment to project design and public acceptance, not only in Arkansas but in other Delta states. Research needed to improve this state of affairs is listed. |