Map, Data, and GIS Files Pertaining to the Agricultural Irrigated Land-use Inventory for the Counties in the Suwannee River Water Management District, 2015

A detailed inventory of irrigated crop acreage is not available at the level of resolution needed to accurately estimate agricultural water-use or to project future water demands in many Florida counties. A detailed digital map and summary of irrigated acreage during the 2015 growing season was developed for 13 of the 15 counties that compose the Suwannee River Water Management District. The irrigated areas were delineated using land-use data, orthoimagery, and information obtained from the water management district consumptive water-use permits, and they were field-verified between May and November 2015. Selected attribute data were collected for the irrigated areas, including crop type, primary water source, and type of irrigation system. Results indicate that an estimated 113,134 acres were either irrigated or had potential for irrigation in all or part of the 13 counties that comprise the Suwannee River Water Management District during 2015. This estimate includes 108,870 acres of field-verified crops and 4,264 acres of irrigated land observed as idle (with an irrigation system visible but no crop present at the time of the field verification visit), acres that could not be verified during field visits, or were located on publicly owned research lands. Of the total field-verified crops, 83,721 acres were field crops, 20,962 acres were vegetable crops (sometimes referred to as row crops), 3,089 acres were in tree nurseries, ornamentals, and sod production, and 1,098 acres were in fruit crops. Specific irrigated crops include 32,468 acres of corn (for silage), 28,170 acres of peanuts, and 10,331 acres of hay. About 40 percent of the vegetable acreage (8,340 acres) was double cropped (planted with both a spring and a fall crop on the same field). Beans, carrots and watermelons were the most commonly grown vegetable crops in these 13 counties in 2015. Sprinkler irrigation systems, including center pivots, portable or traveling guns, and permanent or solid overhead fixtures accounted for nearly 91 percent (102,874 acres) of the total acreage irrigated in Suwannee River Water Management District, whereas micro irrigation systems including drip irrigation accounted for 9 percent (10,260 acres) of the irrigated acreage. A total of 1,466 center pivots were observed during field verification in 2015 and accounted for 93,093 irrigated acres. Most center pivots were in use at the time of the field verification, although about 3 percent appeared idle. No flood irrigation systems were observed during field verification in 2015. Overall, groundwater was used to irrigate nearly all of the observed field verified acreage (98.8 percent). Dairy wastewater effluent was used on many fields within during 2015; however, a quantitative estimate of acreage using effluent could not be determined. Irrigated cropland totaled 26,927 acres in Suwannee County; 16,511 acres in Madison County; 14,862 acres in Hamilton County; and 14,155 in Gilchrist County; these four counties accounted for nearly two-thirds (64 percent) of the acres irrigated within the Suwannee River Water Management District during 2015. For Suwannee, Madison, and Gilchrist counties, corn (primarily for silage) and peanuts were the primary irrigated crops, accounting for 48, 70, and 71 percent, respectively; vegetables accounted for 52 percent of the total irrigated acres in Hamilton County. Other counties with significant acres irrigated include Levy (10,122 acres), Alachua (9,547 acres), and Lafayette (8,110 acres); these three counties, combined with Suwannee, Madison, Hamilton, and Gilchrist counties, accounted for 88 percent of the irrigated acreage. The irrigated acreage field verified in 2015 for the 13 counties in the Suwannee River Water Management District only (113,134 acres) is about 6 percent higher than the estimated acreage published for 2012 by the U.S. Department of Agriculture (107,217 acres), however, this value represents the entire acreage for all 13 counties. Differences between the U.S. Department of Agriculture 2012 values and the 2015 field-verified estimates may occur because (1) irrigated acreage for some specific crops increased or decreased substantially during the 3-year interval due to commodity prices or economic changes, (2) calculated field verified irrigated acreage may be an overestimate because irrigation was assumed if an irrigation system was present and therefore the acreage was counted as irrigated, when in fact some farmers may not have used their irrigation systems during this growing period even if they had a crop in the field, or (3) the amount of irrigated acreages published by the U.S. Department of Agriculture for selected crops may be underestimated in some cases.