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Richard L. Marella

Publications and source records attributed to Richard L. Marella.

18 recordsLinked to original sources
USGS2022

Verification of irrigated agricultural land acreage in 55 counties in Florida, 2013–21

In 2012, the Florida Legislature mandated that the Florida Department of Agriculture and Consumer Services (FDACS), Office of Agricultural Water Policy, promote an agricultural water-conservation program that would include a cost-share program and best management practices and that would aid the five water management districts in the development of consistent agricultural water-supply planning, assisting the districts in projecting future agricultural water needs and promoting consistency in water-use estimates among the districts. Beginning in 2013, the FDACS created a series of agriculture and irrigated land-use maps for all Florida counties for the purpose of estimating current and forecasting future water demands. These maps, produced and updated periodically by The Balmoral Group, were based on baseline data from 2010 and have been updated with a combination of satellite images and land-use data from water management districts in subsequent years (2013–21) to help create a statewide database of irrigated agricultural lands. The purpose of this multiyear cooperative study between the U.S. Geological Survey and the FDACS is to provide (1) a detailed geospatial database of verified irrigated field locations with selected attributes as ArcGIS shapefiles and (2) aggregated acreage totals by crop type for all or parts of 55 of the 67 counties within Florida. Ten of the remaining 12 counties were fully mapped by the St. John’s River Water Management District in 2015; the other 2 counties were not mapped because they contained very little irrigated agricultural land. Irrigated agricultural fields identified on The Balmoral Group baseline maps for each of the 55 counties were either physically observed by U.S. Geological Survey or were verified through water management district’s consumptive water-use permit database. A select group of counties were chosen to be field verified each year, concluding with a total of 55 counties in Florida field verified between October 2013 and August 2021. The results provided from this multiyear study can help increase the accuracy of irrigation water-use estimates for counties in Florida.

Florida↗
USGS2020

Water withdrawals, uses, and trends in Florida, 2015

In 2015, the total amount of water withdrawn in Florida was estimated to be 15,319 million gallons per day (Mgal/d). Saline water accounted for 9,598 Mgal/d (63 percent) and freshwater accounted for 5,721 Mgal/d (37 percent) of the total. Groundwater accounted for 3,604 Mgal/d (63 percent) of freshwater withdrawals and surface water accounted for the remaining 2,117 Mgal/d (37 percent). Surface-water sources accounted for 9,401 Mgal/d (98 percent) of the saline-water withdrawals, and groundwater sources accounted for the remaining 198 Mgal/d (2 percent). The majority of groundwater withdrawals (almost 62 percent) in 2015 were from the Floridan aquifer system, which is used throughout most of the State while the majority of fresh surface-water withdrawals (52 percent) occurred in the Southern Florida Subregion, a hydrologic unit that includes Lake Okeechobee and canals in the Everglades Agricultural Area. Groundwater provided drinking water (public supplied and self-supplied) for 18.324 million people (92 percent of Florida’s population), and fresh surface water provided drinking water for 1.491 million people (8 percent). Overall, public supply accounted for 39 percent of the total freshwater withdrawals (ground and surface) and 53 percent of groundwater withdrawals, followed by agricultural self-supplied uses, which accounted for 37 percent of the total freshwater withdrawals and 28 percent of groundwater withdrawals. Other self-supplied groundwater withdrawals include commercial-industrial-mining self-supplied (8 percent), recreational-landscape irrigation and domestic self-supplied (5 percent each), and power generation (less than 1 percent). Agricultural self-supplied withdrawals accounted for 51 percent of fresh surface-water withdrawals, followed by power generation (19 percent), public supply (15 percent), recreational-landscape irrigation (10 percent), and commercial-industrial-mining self-supplied (5 percent). In 1975, agricultural water withdrawals accounted for 43 percent of the total freshwater withdrawals, followed by power generation (24 percent) and public supply (17 percent). By 2000, agricultural withdrawals increased to 48 percent of the total freshwater withdrawals, followed by public supply (30 percent). For 2015, agricultural self-supplied decreased to 37 percent of total freshwater withdrawals, and was surpassed by public supply at 39 percent. Over the 40-year period between 1975 and 2015, increases in freshwater withdrawals caused by large gains in population and the expansion of irrigated acreage were offset by decreases in water used for power generation and commercial-industrial-mining withdrawals. Since 2000, however, irrigated acreage has decreased statewide because of crop disease, storm damage, and urbanization. This decline, coupled with large gains in water conservation measures in the farming industry, has led to agricultural withdrawals in Florida being less than public-supply withdrawals for the first time since water-use data were first reported in 1965.

Florida↗
USGS2017

Agricultural irrigated land-use inventory for Polk County, Florida, 2016

An accurate inventory of irrigated crop acreage is not available at the level of resolution needed to better estimate agricultural water use or to project future water demands in many Florida counties. A detailed digital map and summary of irrigated acreage was developed for Polk County, Florida, during the 2016 growing season. This cooperative project between the U.S. Geological Survey and the Office of Agricultural Water Policy of the Florida Department of Agriculture and Consumer Services is part of an effort to improve estimates of water use and projections of future demands across all counties in the State. The irrigated areas were delineated by using land-use data provided by the Florida Department of Agriculture and Consumer Services, along with information obtained from the South and Southwest Florida Water Management Districts consumptive water-use permits. Delineations were field verified between April and December 2016. Attribute data such as crop type, primary water source, and type of irrigation system were assigned to the irrigated areas. The results of this inventory and field verification indicate that during the 2016 growing seasons (spring, summer, fall, and winter), an estimated 88,652 acres were irrigated within Polk County. Of the total field-verified crops, 83,995 acres were in citrus; 2,893 acres were in other non-citrus fruit crops (blueberries, grapes, peaches, and strawberries); 621 acres were in row crops (primarily beans and watermelons); 1,117 acres were in nursery (container and tree farms) and sod production; and 26 acres were in field crops including hay and pasture. Of the total inventoried irrigated acreage within Polk County, 98 percent (86,566 acres) was in the Southwest Florida Water Management District, and the remaining 2 percent (2,086 acres) was in the South Florida Water Management District. About 85,788 acres (96.8 percent of the acreage inventoried) were irrigated by a microirrigation system, including drip, bubblers, and spray emitters. The remaining 3.2 percent of the irrigated acreage was irrigated by a sprinkler system (2,360 acres) or subsurface flood systems (504 acres). Groundwater was the primary source of water used on irrigated acreage (88 percent, or 78,050 acres); the remaining 10,602 acres (12 percent) used groundwater combined with surface water as the irrigation source. The irrigated acreage estimated by the U.S. Geological Survey (USGS) for this 2016 inventory (88,652 acres) is about 11 percent higher than the 79,869 acres estimated by the U.S. Department of Agriculture (USDA) for 2012. Citrus and pasture in Polk County show the biggest difference in irrigated acreage between the USGS and USDA totals. Irrigated citrus acreage inventoried in 2016 by the USGS totaled 83,996 acres, whereas the USDA reported 78,305 acres of citrus in 2012. The USGS identified 6 acres of irrigated pasture and 20 acres of hay, whereas the USDA reported 6,631 acres of irrigated pasture and 1,349 acres of hay for 2012. In general, differences between the 2016 USGS field-verified acreage totals and acreage published by the USDA for 2012 could be due to (1) irrigated acreage for some specific crops increased or decreased substantially during the 4-year interval between 2012 and 2016 because of production or economic changes, (2) the assumption that if an irrigation system was present, it was used in 2016, when in fact some landowners 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 acreage published by the USDA for selected crops may be underestimated as a result of how information is obtained and formulated by the agency during census compilations.

Florida↗
USGS2016

Agricultural irrigated land-use inventory for the counties in the Suwannee River Water Management District in Florida, 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 that were then field verified between May and November of 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 within the Suwannee River Water Management District during 2015. This estimate includes 108,870 acres of field-verified, irrigated crops and 4,264 acres of irrigated land observed as (1) idle (with an irrigation system visible but no crop present at the time of the field-verification visit), (2) acres that could not be verified during field visits, or (3) acres that 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 fruit crops. Specific irrigated crops included 32,468 acres of corn (primarily 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 irrigated acreage in the Suwannee River Water Management District, whereas microirrigation 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 (which represents 82 percent of the total irrigated acreage). 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 field-verified acreage (99.8 percent). Dairy wastewater effluent was used on many fields 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 acres 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. Corn (primarily for silage) and peanuts were the primary irrigated crops, accounting for 48, 70, and 71 percent, respectively, of the total irrigated acreage in Suwannee, Madison, and Gilchrist Counties; vegetables accounted for 52 percent of the total irrigated acres in Hamilton County. Other counties with substantial irrigated acreage included 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 in the Suwannee River Water Management District. The irrigated acreage that was field verified in 2015 for the 13 counties in the Suwannee River Water Management District (113,134 acres) is about 6 percent higher than the estimated acreage published by the U.S. Department of Agriculture (107,217 acres) for 2012; however, this 2012 value represents acreage for the entire portion of all 13 counties, not just the Suwannee River Water Management District portion. Differences between the 2015 field-verified acreage totals and those published by the U.S. Department of Agriculture for 2012 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 that may not have been the case as 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.

Florida↗
USGS2015

Agricultural irrigated land-use inventory for Jackson, Calhoun, and Gadsden Counties in Florida, and Houston County in Alabama, 2014

A detailed inventory of irrigated crop acreage is not available at the level of resolution needed to accurately estimate water use or to project future water demands in many Florida counties. This report provides a detailed digital map and summary of irrigated areas for 2014 within Jackson, Calhoun, and Gadsden Counties in Florida, and Houston County in Alabama. The irrigated areas were delineated using land-use data and orthoimagery that were then field verified between June and November 2014. Selected attribute data were collected for the irrigated areas, including crop type, primary water source, and type of irrigation system. Results of the 2014 study indicate that an estimated 31,608 acres were irrigated in Jackson County during 2014. This estimate includes 25,733 acres of field crops, 1,534 acres of ornamentals and grasses (including pasture), and 420 acres of orchards. Specific irrigated crops include cotton (11,759 acres), peanuts (9,909 acres), field corn (2,444 acres), and 3,235 acres of various vegetable (row) crops. The vegetable acreage includes 1,714 acres of which 857 acres were planted with both a spring and fall crop on the same field (double cropped). Overall, groundwater was used to irrigate 98.6 percent of the total irrigated acreage in Jackson County during 2014, whereas surface water and wastewater were used to irrigate the remaining 1.4 percent. Irrigated cropland totaled 3,060 acres in Calhoun County; 4,547 acres in Gadsden County; and 10,333 acres in Houston County. In Calhoun County, sod accounted for the largest irrigated acreage (1,145 acres) followed by peanuts (886 acres). In Gadsden County, ornamentals accounted for the largest irrigated acreage (1,104 acres) followed by cotton (977 acres). In Houston County, cotton accounted for the largest irrigated acreage (4,310 acres) followed by peanuts (2,493 acres). Overall, an estimated 49,548 acres of land were irrigated during 2014 in the four counties inventoried. About 45,052 acres were irrigated by a center pivot, permanent or solid overhead fixtures, or a portable or traveling gun. In all, 650 center pivot irrigation systems were identified, and the calculated acreage under these pivots totaled 43,070 acres. There were 405 center pivot irrigation systems counted in Jackson County during the 2014 field verification followed by Houston with 197, Gadsden with 48, and Calhoun with 10. An estimated 35,087 acres of field corn, cotton, peanuts, and sorghum were irrigated by center pivot systems during 2014 in these four counties combined. Vegetable acreage for the four counties combined totaled 6,699 acres, with 54 percent being irrigated by a drip irrigation system and the remaining 46 percent irrigated by a center pivot or traveling gun. The irrigated acreage estimated for Jackson County in 2014 (31,608) is about 47 percent higher than the 2012 estimated acreage published by the USDA (21,508 acres). The estimates of irrigated acreage field verified during 2014 for Calhoun and Gadsden Counties are also higher than those published by the USDA for 2012 (86 percent and 71 percent, respectively). In Calhoun County the USDA reported 1,647 irrigated acres while the current study estimated 3,060 acres, and in Gadsden County the USDA reported 2,650 acres while the current study estimated 4,547 acres. For Houston County the USDA-reported value of 9,138 acres in 2012 was 13 percent below the 10,333 acres field verified in the current study. Differences between the USDA 2012 values and 2014 field verified estimates in these two datasets may occur because (1) irrigated acreage for some specific crops increased or decreased substantially during the 2-year interval due to commodity prices or economic changes, (2) irrigated acreage calculated for the current study may be estimated high because irrigation was assumed if an irrigation system was present and therefore the acreage was counted as irrigated, when in fact that may not have been the case as 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 USDA for selected crops may be underestimated in some cases.

Alabama, Florida↗
USGS2015

Water withdrawals in Florida, 2012

In 2012, the total amount of water withdrawn in Florida was estimated to be 14,237 million gallons per day (Mgal/d). Saline water accounted for 7,855 Mgal/d (55 percent), and freshwater accounted for 6,383 Mgal/d (45 percent). Groundwater accounted for 4,167 Mgal/d (65 percent) of freshwater withdrawals, and surface water accounted for the remaining 2,216 Mgal/d (35 percent). Surface water accounted for nearly all (99.9 percent) saline-water withdrawals. Freshwater withdrawals were greatest in Palm Beach County (682 Mgal/d), and saline-water withdrawals were greatest in Pasco County (1,822 Mgal/d). Fresh groundwater provided drinking water (through either public supply or private domestic wells) for 17.699 million residents (93 percent of Florida’s population), and fresh surface water provided drinking water for 1.375 million residents (7 percent). The statewide public-supply gross per capita water use for 2012 was estimated at 136 gallons per day. Overall, agricultural self-supplied accounted for 39 percent of the total freshwater withdrawals (groundwater and surface water), followed by public supply (36 percent). Public supply accounted for 49 percent of groundwater withdrawals, followed by agricultural self-supplied (34 percent), commercial-industrial-mining self-supplied (7 percent), recreational-landscape irrigation and domestic self-supplied (5 percent each), and power generation (less than 1 percent). Agricultural self-supplied accounted for 50 percent of fresh surface-water withdrawals, followed by power generation (26 percent), public supply (11 percent), recreational-landscape irrigation (9 percent), and commercial-industrial-mining self-supplied (4 percent). Power generation accounted for nearly all (99.8 percent) saline-water withdrawals. The largest percentage of freshwater withdrawals was from the South Florida Water Management District (46 percent), followed by the St. Johns River Water Management District (20 percent), Southwest Florida Water Management District (19 percent), Northwest Florida Water Management District (9 percent), and Suwannee River Water Management District (6 percent). The South Florida Water Management District accounted for the largest percentage of freshwater withdrawals for public-supply use (46 percent), commercial-industrial-mining self-supplied use (24 percent), agricultural self-supplied use (59 percent), and recreational-landscape irrigation use (63 percent). The Northwest Florida Water Management District accounted for the largest percentage of freshwater withdrawals for power-generation use (44 percent), and the Southwest Florida Water Management District accounted for the largest percentage of saline-water withdrawals for power-generation use (58 percent).

Florida↗
USGS2014

Agricultural irrigated land-use inventory for Osceola County, Florida, October 2013-April 2014

A detailed inventory of irrigated crop acreage is not available at the level of resolution needed to increase the accuracy of current water-use estimates or to project future water demands in many Florida counties. This report provides a detailed digital map and summary of irrigated areas within Osceola County for the agricultural growing period October 2013–April 2014. The irrigated areas were first delineated using land-use data and satellite imagery and then field verified between February and April 2014. 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 27,450 acres were irrigated during the study period. This includes 4,370 acres of vegetables, 10,970 acres of orchard crops, 1,620 acres of field crops, and 10,490 acres of ornamentals and grasses. Specifically, irrigated acreage included citrus (10,860 acres), sod (5,640 acres), pasture (4,580 acres), and potatoes (3,320 acres). Overall, groundwater was used to irrigate 18,350 acres (67 percent of the total acreage), and surface water was used to irrigate the remaining 9,100 acres (33 percent). Microirrigation systems accounted for 45 percent of the total acreage irrigated, flood systems 30 percent, and sprinkler systems the remaining 25 percent. An accurate, detailed, spatially referenced, and field-verified inventory of irrigated crop acreage can be used to assist resource managers making current and future county-level water-use estimates in Osceola County.

Florida↗
USGS2014

Water withdrawals, use, and trends in Florida, 2010

In 2010, the total amount of water withdrawn in Florida was estimated to be 14,988 million gallons per day (Mgal/d). Saline water accounted for 8,589 Mgal/d (57 percent) and freshwater accounted for 6,399 Mgal/d (43 percent). Groundwater accounted for 4,166 Mgal/d (65 percent) of freshwater withdrawals, and surface water accounted for the remaining 2,233 Mgal/d (35 percent). Surface water accounted for nearly all (99.9 percent) saline-water withdrawals. An additional 659 Mgal/d of reclaimed wastewater was used in Florida during 2010. Freshwater withdrawals were greatest in Palm Beach County (707 Mgal/d), and saline-water withdrawals were greatest in Hillsborough County (1,715 Mgal/d). Fresh groundwater provided drinking water (public supplied and self-supplied) for 17.33 million people (92 percent of Florida’s population), and fresh surface water provided drinking water for 1.47 million people (8 percent). The statewide public-supply gross per capita use for 2010 was 134 gallons per day, whereas the statewide public-supply domestic per capita use was 85 gallons per day. The majority of groundwater withdrawals (almost 62 percent) in 2010 were obtained from the Floridan aquifer system, which is present throughout most of the State. The majority of fresh surface-water withdrawals (56 percent) came from the southern Florida hydrologic unit subregion and is associated with Lake Okeechobee and the canals in the Everglades Agricultural Area of Glades, Hendry, and Palm Beach Counties, as well as the Caloosahatchee River and its tributaries in the agricultural areas of Collier, Glades, Hendry, and Lee Counties. Overall, agricultural irrigation accounted for 40 percent of the total freshwater withdrawals (ground and surface), followed by public supply with 35 percent. Public supply accounted for 48 percent of groundwater withdrawals, followed by agricultural self-supplied (34 percent), commercial-industrial-mining self-supplied (7 percent), recreational-landscape irrigation and domestic self-supplied (5 percent each), and power generation (less than 1 percent). Agricultural self-supplied accounted for 51 percent of fresh surface-water withdrawals, followed by power generation (25 percent), public supply (11 percent), recreational-landscape irrigation (9 percent), and commercial-industrial-mining self-supplied (4 percent). Power generation accounted for nearly all (99.8 percent) saline-water withdrawals. Of the 18.80 million people who resided in Florida during 2010, 41 percent (7.68 million people) resided in the South Florida Water Management District (SFWMD), 25 percent each resided in the Southwest Florida Water Management District (SWFWMD) and the St. Johns River Water Management District (SJRWMD) (4.73 and 4.70 million people, respectively), 7 percent (1.36 million people) resided in the Northwest Florida Water Management District (NWFWMD), and 2 percent (0.33 million people) resided in the Suwannee River Water Management District (SRWMD). The largest percentage of freshwater withdrawals was from the SFWMD (47 percent), followed by the SJRWMD (21 percent), SWFWMD (18 percent), NWFWMD (9 percent), and SRWMD (5 percent). Between 1950 and 2010, the population of Florida increased by 16.03 million (580 percent), and the total water withdrawals (fresh and saline) increased by 12,334 Mgal/d (465 percent). More recently, total freshwater withdrawals decreased by more than 1,792 Mgal/d (22 percent) between 2000 and 2010, while the population increased by 2.82 million (18 percent), and total freshwater withdrawals decreased by more than 474 Mgal/d (7 percent) between 2005 and 2010, while the population increased by 0.88 million (8 percent). The recent trend of decreases in freshwater withdrawals is a result of increased rainfall during this period, the development and use of alternative water sources, water conservation efforts, more conservative regulations and mandates, changes in economic conditions, and losses of irrigated lands. Fresh-water withdrawals for public supply, agricultural self-supplied use, and commercial-industrial-mining self-supplied use all decreased between 2000 and 2010 and between 2005 and 2010, whereas freshwater withdrawals for domestic self-supplied use, recreational-landscape irrigation use, and power generation use either remained the same or changed slightly during the decade. The use of highly mineralized groundwater (referred to as nonpotable water) as a source of drinking water has increased in Florida. Nonpotable water use for public supply has increased from nearly 2 Mgal/d in 1970 to about 165 Mgal/d in 2010. Nonpotable water is either blended or treated to meet drinking-water standards and is mostly used along the east and west coasts of central and southern Florida. The use of reclaimed wastewater increased from about 206 Mgal/d in 1986 to nearly 659 Mgal/d in 2010. More than three-quarters (79 percent) of reclaimed wastewater in 2010 was used to supplement potable-quality water withdrawals for urban irrigation, agricultural irrigation, and industrial use.

Florida↗
USGS2011

Water withdrawals, wastewater discharge, and water consumption in the Apalachicola-Chattahoochee-Flint River Basin, 2005, and water-use trends, 1970-2005

The Apalachicola-Chattahoochee-Flint (ACF) River Basin covers about 20,500 square miles that drains parts of Alabama, Florida, and Georgia. The basin extends from its headwaters northern Georgia to the Gulf of Mexico. Population in the basin was estimated to be 3.7 million in 2005, an increase of about 41 percent from the 1990 population of 2.6 million. In 2005, slightly more than 721,000 acres of crops were irrigated within the basin. In 2005, the total amount of water withdrawn in the ACF River Basin was about 1,990 million gallons per day (Mgal/d). Of this, surface water accounted for 1,591 Mgal/d (80 percent) and groundwater accounted for 399 Mgal/d (20 percent). Surface water was the primary water source of withdrawals in the northern and central parts of the basin, and groundwater was the primary source in the southern part. The largest surface-water withdrawals was from Cobb County, Georgia (410 Mgal/d, mostly from the Chattahoochee River and Lake Alatoona), and the largest groundwater withdrawals was from Dougherty County, Georgia (38 Mgal/d, mostly from the Upper Floridan aquifer system). Thermoelectric power generation accounted for the largest water withdrawals in 2005 at 788 Mgal/d (40 percent). Most of these withdrawals were used for once-through cooling, and nearly all water used for this purpose was returned to its source. Public supply accounted for 609 Mgal/d (30 percent) of total withdrawals in 2005, followed by agricultural self-supplied (including crop, golf course irrigation, and livestock) at 365 Mgal/d (18 percent), commercial-industrial self-supplied (including mining) at 191 Mgal/d (10 percent), and domestic self-supplied at 37 Mgal/d (2 percent). Public-supply withdrawals were lowest during January, February, and March (about 500 Mgal/d), and highest during September (about 700 Mgal/d). As the population of the ACF River Basin increased by 1.7 million (83 percent) in the 35 years between 1970 and 2005, total withdrawals in the basin increased by more than 515 Mgal/d (35 percent). Of this increase, surface-water accounted for 206 Mgal/d (15 percent) and groundwater accounted for 309 Mgal/d (350 percent). Since 1980, total water withdrawals have generally declined, except in 2000 when they peaked because of below-average rainfall. In 2000, an estimated 49 percent of the water withdrawn for public supply in the basin was consumed, and the remaining 51 percent was returned to the hydrologic system through wastewater treatment systems. In 2005, an estimated 38 percent was consumed and 62 percent was returned to the hydrologic system. This contrast between water withdrawals and wastewater discharges for these years was caused primarily by below-average rainfall during 2000 (a dry year) and above-average rainfall during 2005 (a wet year).

Scientific Investigations Report↗
USGS2009

Water Withdrawals, Use, and Trends in Florida, 2005

In 2005, the total amount of water withdrawals in Florida was estimated at 18,359 million gallons per day (Mgal/d). Saline water accounted for 11,486 Mgal/d (63 percent), and freshwater accounted for 6,873 Mgal/d (37 percent). Groundwater accounted for 4,247 Mgal/d (62 percent) of freshwater withdrawals, and surface water accounted for the remaining 2,626 Mgal/d (38 percent). Surface water accounted for nearly all (99.9 percent) saline-water withdrawals. An additional 660 Mgal/d of reclaimed wastewater was used in Florida during 2005. The largest amount of freshwater was withdrawn from Palm Beach County, and the largest amount of saline water was withdrawn from Pasco County. Fresh groundwater provided drinking water (public supplied and self-supplied) for 16.19 million people (90 percent of Florida's population), and fresh surface water provided drinking water for 1.73 million people (10 percent). The majority of groundwater withdrawals (nearly 60 percent) in 2005 was obtained from the Floridan aquifer system which is present throughout the entire State. The majority of fresh surface-water withdrawals (59 percent) came from the southern Florida hydrologic unit subregion and is associated with Lake Okeechobee and the canals in the Everglades Agricultural Area of Glades, Hendry, and Palm Beach Counties, as well as the Caloosahatchee River and its tributaries in the agricultural areas of Collier, Glades, Hendry, and Lee Counties. Overall, agricultural irrigation accounted for 40 percent of the total freshwater withdrawals (ground and surface), followed by public supply with 37 percent. Public supply accounted for 52 percent of groundwater withdrawals, followed by agricultural self-supplied (31 percent), ommercial-industrial-mining self-supplied (8.5 percent), recreational irrigation and domestic self-supplied (4 percent each), and power generation (0.5 percent). Agricultural self-supplied accounted for 56 percent of fresh surface-water withdrawals, followed by power generation (20.5 percent), public supply (13 percent), recreational irrigation (6 percent), and commercial-industrial self-supplied (4.5 percent). Power generation accounted for nearly all (99.9 percent) saline-water withdrawals. Of the 17.92 million people who resided in Florida during 2005, 41 percent (7.36 million people) resided in the South Florida Water Management District (SFWMD), followed by the St. Johns River Water Management District (SJRWMD) and the Southwest Florida Water Management District (SWFWMD) with 25 percent each (4.46 and 4.44 million people, respectively), the Northwest Florida Water Management District (NWFWMD) with 7.5 percent (1.34 million people), and the Suwannee River Water Management District (SRWMD) with 1.5 percent (0.32 million people). The largest amount of freshwater withdrawals was from the SFWMD, which was one-half (50 percent) of the State's total freshwater withdrawals, followed by the SJRWMD (19 percent), SWFWMD (16 percent), NWFWMD (10 percent), and SRWMD (5 percent). Between 1950 and 2005, the population of Florida increased by 15.15 million (550 percent), and the total water withdrawals (fresh and saline) increased 15,700 Mgal/d (600 percent). More recently, total withdrawals decreased 1,790 Mgal/d (9 percent) between 2000 and 2005, but the total population increased by 1.94 million (12 percent). Between 1990 and 2005, saline-water withdrawals increased 1,120 Mgal/d (11 percent), whereas between 2000 and 2005, saline-water withdrawals decreased 470 Mgal/d (4 percent). Between 1990 and 2005, freshwater withdrawals decreased 710 Mgal/d (9 percent), whereas between 2000 and 2005, freshwater withdrawals decreased 1,320 Mgal/d (16 percent). The use of highly mineralized groundwater as a source of supply, primarily for public supply, also has increased in Florida. This water, referred as nonpotable water, increased from just less than 2 Mgal/d in 1970, to 142 Mgal/d in 2005. Nonpotable water is treated to meet drin

Scientific Investigations Report↗
USGS2008

Water Use in Florida, 2005 and Trends 1950-2005

Water is among Florida's most valued resources. The State has more than 1,700 streams and rivers, 7,800 freshwater lakes, 700 springs, 11 million acres of wetlands, and underlying aquifers yielding quantities of freshwater necessary for both human and environmental needs (Fernald and Purdum, 1998). Although renewable, these water resources are finite, and continued growth in population, tourism, and agriculture will place increased demands on these water supplies. The permanent population of Florida in 2005 totaled 17.9 million, ranking fourth in the Nation (University of Florida, 2006); nearly 86 million tourists visited the State (Orlando Business Journal, 2006). In 2005, Florida harvested two-thirds of the total citrus production in the United States and ranked fifth in the Nation net farm income (Florida Department of Agriculture and Consumer Services, 2006). Freshwater is vital for sustaining Florida's population, economy, and agricultural production. Accurate estimates reflecting water use and trends in Florida are compiled in 5-year intervals by the U.S. Geological Survey (USGS) in cooperation with the Florida Department of Environmental Protection (FDEP) and the Northwest Florida, St. Johns River, South Florida, Southwest Florida, and Suwannee River Water Management Districts (Marella, 2004). This coordinated effort provides the necessary data and information for planning future water needs and resource management. The purpose of this fact sheet is to present the highlights of water use in Florida for 2005 along with some significant trends in withdrawals since 1950.

Fact Sheet↗
USGS2006

Drought of 1998-2002: impacts on Florida's hydrology and landscape

Lower than normal precipitation caused a severe statewide drought in Florida from 1998 to 2002. Based on precipitation and streamflow records dating to the early 1900s, the drought was one of the worst ever to affect the State. In terms of severity, this drought was comparable to the drought of 1949-1957 in duration and had record-setting low flows in several basins. The drought was particularly severe over the 5-year period in the northwest, northeast, and southwest regions of Florida, where rainfall deficits ranged from 9-10 in. below normal (southwest Florida) to 38-40 in. below normal (northwest Florida). Within these regions, the drought caused record-low streamflows in several river basins, increased freshwater withdrawals, and created hazardous conditions ripe for wildfires, sinkhole development, and even the draining of lakes. South Florida was affected primarily in 2001, when the region experienced below-average streamflow conditions; however, cumulative rainfall in south Florida never fell below the 30-year normal. The four regions of Florida, as referred to throughout this report, are defined based upon U.S. Geological Survey (USGS) data collection regions in Florida. Record-low flows were reported at several streamflow-gaging stations throughout the State, including the Withlacoochee River at Trilby, which reached zero flow on June 10-11, 2000, for the first time during the period of record (1928-2004). Streamflow conditions varied across the State from 31 percent of average flow in 2000 in southwest Florida, to 100 percent of average in 1999 in south Florida. Low-flow recurrence intervals during the drought ranged from less than 2 years at three locations to greater than 50 years at many locations. During the 1998-2002 drought, ground-water levels at many wells across the State declined to elevations not seen in many years. At some wells, ground-water levels reached record lows for their period of record. Florida Water Management Districts responded by issuing water-shortage mandates to curb water use during the spring months of 2000. Generally, freshwater withdrawals increased 13 percent between 1995 and 2000 as a result of the dry conditions. Hundreds of new sinkholes developed across the State. Lake Jackson, in northwest Florida near Tallahassee, experienced its eighth and ninth drawdowns of the past 100 years, and became nearly dry. Numerous other lakes in northern and central Florida experienced similar events. Water restrictions were put into effect in urban areas of the northeast, southwest, and south Florida regions. Wildfires periodically raged over parts of Florida throughout the period, when tinder-dry undergrowth caught fire from lightning strikes or manmade causes. Smoke from these fires caused traffic delays as sections of major highways and interstate lanes forced traffic to slow to a crawl or were closed. Wildfire statistics (Florida Division of Forestry) show that 25,137 fires burned 1.5 million acres between 1998 and 2002. Finally, rainfall that occurred in late 2002, in 2003, and from a tropical storm and four hurricanes in 2004 ended this drought.

Circular↗
USGS2005

Impact of anthropogenic development on coastal ground-water hydrology in southeastern Florida, 1900-2000

Southeastern Florida is an area that has been subject to widely conflicting anthropogenic stress to the Everglades and coastal ecosystems. This stress is a direct consequence of the 20th century economic competition for limited land and water resources needed to satisfy agricultural development and its expansion, its displacement by burgeoning urban development, and the accompanying growth of the limestone mining industry. The development of a highly controlled water-management system designed to reclaim land for urban and agricultural development has severely impacted the extent, character, and vitality of the historic Everglades and coastal ecosystems. An extensive conveyance system of canals, levees, impoundments, surface- water control structures, and numerous municipal well fields are used to sustain the present-day Everglades hydrologic system, prevent overland flow from moving eastward and flooding urban and agricultural areas, maintain water levels to prevent saltwater intrusion, and provide an adequate water supply. Extractive mining activities expanded considerably in the latter part of the 20th century, largely in response to urban construction needs. Much of the present-day urban-agricultural corridor of southeastern Florida lies within an area that is no more than 15 feet above NGVD 1929 and formerly characterized by freshwater marsh, upland, and saline coastal wetland ecosystems. Miami- Dade, Broward, and Palm Beach Counties have experienced explosive population growth, increasing from less than 4,000 inhabitants in 1900 to more than 5 million in 2000. Ground-water use, the principal source of municipal supply, has increased from about 65 Mgal/d (million gallons per day) obtained from 3 well fields in 1930 to more than 770 Mgal/d obtained from 65 well fields in 1995. Water use for agricultural supply increased from 505 Mgal/d in 1953 to nearly 1,150 Mgal/d in 1988, but has since declined to 764 Mgal/d in 1995, partly as a result of displacement of the agricultural industry by urban growth. Present-day agricultural supplies are obtained largely from surface-water sources in Palm Beach County and ground-water sources in Miami-Dade County, whereas Broward County agricultural growers have been largely displaced. The construction of a complex canal drainage system and large well fields has substantially altered the surface- and ground-water hydrologic systems. The drainage system constructed between 1910 and 1928 mostly failed to transport flood flows, however, and exacerbated periods of low rainfall and drought by overdraining the surficial aquifer system. Following completion of the 1930s Hoover Dike levee system that was designed to reduce Lake Okeechobee flood flows, the Central and Southern Florida Flood Control Project initiated the restructure of the existing conveyance system in 1948 through canal expansion, construction of protective levees and control structures, and greater management of ground-water levels in the surficial aquifer system. Gated canal control structures discharge excess surface water during the wet season and remain closed during the dry season to induce recharge by canal seepage and well withdrawals. Management of surface water through canal systems has successfully maintained lower ground-water levels inland to curb urban and agricultural flooding, and has been used to increase ground-water levels near the coast to impede saltwater intrusion. Coastal discharge, however, appears to have declined, due in part to water being rerouted to secondary canals, and to induced recharge to the surficial aquifer system by large municipal withdrawals. Southeastern Florida is underlain by Holocene- to Tertiary-age karstic limestone deposits that form (in descending order): a highly prolific surficial aquifer system, a poorly permeable intermediate confining system, and a permeable Floridan aquifer system. Prior to construction of a complex drainage netwo

Florida↗
USGS2005

Water withdrawals and trends from the Floridan aquifer system in the southeastern United States, 1950-2000

The Floridan aquifer system in the southeastern United States is one of the most productive aquifers in the world (Miller, 1990). This aquifer system underlies an area of about 100,000 square miles in southern Alabama, eastern and southern Georgia, southeastern Mississippi, southern South Carolina, and all of Florida. The Floridan aquifer system is the primary source of water for nearly 10 million people and supports agriculture, industry, and tourism throughout most of the region. In most areas, water from this aquifer is potable and needs very little treatment before use. However, in southern Florida (south of Lake Okeechobee), northwestern Florida and southern Alabama and Mississippi (Pensacola and westward), and eastern South Carolina, water in the aquifer system generally is not potable. The purpose of this report is to: Provide a general description of the Floridan aquifer system; Discuss water withdrawals by category for 2000; Highlight trends in water withdrawals between 1950 and 2000; and Provide a brief summary on the effects that human impacts have on the Floridan aquifer system.

Circular↗
USGS2004

Water withdrawals, use, discharge, and trends in Florida, 2000

In 2000, the estimated amount of water withdrawn in Florida was 20,148 million gallons per day (Mgal/d), of which 59 percent was saline and 41 percent was fresh. Ground water accounted for 62 percent of freshwater withdrawals and surface water accounted for the remaining 38 percent. Ninety-two percent of the 15.98 million people in Florida relied on ground water for their drinking water needs in 2000. Almost all of the saline water withdrawals (99.9 percent) were from surface water. Public supply accounted for 43 percent of ground water withdrawn in 2000, followed by agricultural self-supplied (39 percent), commercial-industrial self-supplied (including mining) (8.5 percent), recreational irrigation (4.5 percent), domestic self-supplied (4 percent), and power generation (1 percent). Agricultural self-supplied accounted for 62 percent of fresh surface water withdrawn in 2000, followed by power generation (20 percent), public supply (8 percent), recreational irrigation (6 percent), and commercial-industrial self-supplied (4 percent). Almost all of saline water withdrawn was used for power generation. The largest amount of freshwater was withdrawn in Palm Beach County and the largest amount of saline water was withdrawn in Hillsborough County. Significant withdrawals (more than 200 Mgal/d) of fresh ground water occurred in Miami-Dade, Polk, Orange, Palm Beach, Broward, and Collier Counties. Significant withdrawals (more than 200 Mgal/d) of fresh surface water occurred in Palm Beach, Hendry, and Escambia Counties. The South Florida Water Management District accounted for the largest amount of freshwater withdrawn (49 percent). About 62 percent of the total ground water withdrawn was from the Floridan aquifer system; 17 percent was from the Biscayne aquifer. Most of the surface water used in Florida was from managed and maintained canal systems or large water bodies. Major sources of fresh surface water include the Caloosahatchee River, Deer Point Lake, Hillsborough River, Lake Okeechobee and associated canals, and the canals associated with the headwaters of the Upper St. Johns River. Freshwater withdrawals increased 46 percent and saline water withdrawals increased 25 percent in Florida between 1970 and 2000. Ground-water withdrawals increased 82 percent, and surface-water withdrawals increased 10 percent during this period. Between 1970 and 2000, total freshwater withdrawals increased for public supply by 176 percent and for agricultural self-supplied by 87 percent; withdrawals for commercial-industrial self-supplied decreased by 37 percent, and power generation (thermoelectric) decreased by 57 percent. Recreational irrigation withdrawals increased 127 percent between 1985 and 2000. Between 1995 and 2000, freshwater withdrawals increased 13 percent, and saline withdrawals increased 9 percent. An estimated 52 percent of the freshwater withdrawn in Florida was consumed; the remaining 48 percent was returned for further use. Domestic wastewater discharged in 2000 totaled 1,495 Mgal/d, of which 44 percent was discharged to surface waters, 34 percent to the ground through land application systems, and 22 percent to deep injection wells. Domestic wastewater discharge increased by 33 percent between 1985 and 2000, but decreased by 3 percent between 1995 and 2000. An estimated 11.21 million people were served by domestic wastewater systems in 2000, whereas the remaining 4.77 million people discharged wastewater to more than 1.95 million septic tanks. Discharge from the septic tanks was estimated to be 263 Mgal/d in 2000.

Scientific Investigations Report↗
USGS1998

Water-Quality Assessment of Southern Florida - Wastewater Discharges and Runoff

Nearly 800 million gallons per day of treated wastewater was discharged in the Southern Florida National Water-Quality Assessment (NAWQA) study unit in 1990, most to the Atlantic Ocean (44 percent) and to deep, saline aquifers (25 percent). About 9 percent was discharged to fresh surface waters and about 22 percent to shallow ground water, of which septic tanks accounted for 9 percent. Runoff from agricultural and urban lands, though not directly measured, is a large source of wastewater in southern Florida.

Fact Sheet↗
USGS1988

Water withdrawals, use, and trends in Florida, 1985

Total water withdrawn for use in Florida for 1985, in million gal/day, was 17,057 of which 6,259, or nearly 37%, was freshwater and 10,798 was saline. The majority of freshwater withdrawn was groundwater (64%) and the majority of saline water withdrawn was surface water (99%). Thermoelectric power generation accounted for more than 99% of saline water withdrawals. Agricultural irrigation accounted for the majority of freshwater withdrawals for both groundwater (41%) and surface water (60%) in 1985. Between 1975-85, Florida 's population increased by nearly 3 million people; tourism increased by nearly 13 million visitors; irrigated agricultural acreage increased by 70,000; freshwater used to support those activities increased by almost 388 million gal/day (excluding fresh surface-water withdrawals for thermoelectric power generation); and fresh groundwater withdrawals increased 718 million gal/day. Groundwater accounted for 64% of Florida 's total freshwater use , up from 51% in 1980 and 48% in 1975. Florida ranked sixth in the Nation in groundwater withdrawals for 1985 with more than 4 ,000 million gal/day withdrawn. Groundwater is the primary source of freshwater in Florida because it is readily available and generally is suitable for most uses. The Floridan aquifer system, which underlies the entire State, supplied the majority (62%) of groundwater in Florida for 1985. In contrast to groundwater, withdrawals of surface water declined between 1975-85. (USGS)

Florida↗