Project ID: 2003GA38B

Title: Decreasing Irrigation Volumes While Maintaining Crop Yields

Project Type: Research

Focus Categories: Irrigation, Agriculture, Water Use

Keywords: irrigation management, water use efficiency, agriculture

Start Date: 03/01/2003

End Date: 02/28/2004

Federal Funds: $18000.00

Matching Funds: $36525.00

Congressional District: GA 2nd

Principal Investigator: Perry, Calvin D

Abstract: Agricultural water use is a major portion of total water consumed in many critical regions of Georgia. Georgia has over 9000 center pivot systems, watering about 1.1 million acres (445,000 ha). Many fields irrigated by these systems have highly variable soils with areas ranging from very sandy to very heavy as well as non-cropped areas. Current irrigation systems are not capable of varying the water application rate to meet the needs of plants on different soil types nor capable of stopping application in non-cropped inclusions. This limitation results in over-applying or under-applying irrigation water. In addition, five years of drought and a lawsuit over Georgia water use by Florida and Alabama have prompted a renewed interest in water conservation methods by the general public, which is becoming increasingly insistent that agriculture do it’s part in conserving water. The University of Georgia / NESPAL Precision Ag Team has developed a prototype method for differentially applying irrigation water to match the precise needs of individual sub-field zones. Recognizing that water is the major yield determiner in nearly all agricultural settings, the original interest lay in varying application rates from a precision crop production viewpoint. However, it was quickly apparent that a method for varying irrigation across a field could also lead to substantial water savings. The method is referred to as Variable-Rate Irrigation (VRI). This system easily retrofits onto existing center pivot irrigation systems.

This research is expected to accomplish the following:
o complete the development of the VRI system that will enable growers to conserve irrigation water while enhancing profitability - both accomplished through site-specific water management. To gather needed application data to verify uniform and variable application rates are being achieved. To gather data needed to verify calculated water savings are being achieved and yields are being enhanced. To gather the economic information needed to effectively manage and justify such variable-rate systems.

Progress/Completion Report PDF