Total Fresh Water Withdrawals

Explanation of Indicator
Florida’s coastal counties depend on their water resources for drinking water, agriculture, industry, and to support the many diverse natural systems found there. Unfortunately, nearly all human activities may adversely affect ground water quality and qu antity in some way. This indicator includes fresh water withdrawn for public supply, self-supplied domestic, commercial-industrial self-supplied, agriculture, and thermoelectric power generation. Most of the saline water withdrawn for commercial-industr ial uses and thermoelectric power generation is not consumed but is used as non-contact cooling water and therefore is not included in these figures. Some saline water is used for public water supplies after being treated with reverse osmosis or after bl ending with fresh water, so these figures are included in the data.

The percent change in total water withdrawn reflects changing demands on this resource. As population pressure increases, the total withdrawals will increase as well.

Data Characteristics
SOURCE
The Water Resources Division of the United States Geological Survey (USGS) is the lead office for information on the millions of gallons of fresh water withdrawn per day. The USGS publishes a report, Water Withdrawals, Use, and Trends in Florida, every f ive years which contains these data. It is prepared in cooperation with the Florida Department of Environmental Protection (DEP) and the water management districts. The publication is prepared by Richard L. Marella, who can be contacted at the USGS, 227 North Bronough Street, Suite 3015, Tallahassee, Florida 32301, or at (904) 942-9500, extension 3004.

ACQUISITION
This information can be obtained in a hard copy format from the Water Resources Division of the USGS. There are no costs associated with obtaining this information.

COLLECTION
The information is collected statewide throughout the year by both DEP and the water management districts, and it is compiled by the USGS about every five years for the above-mentioned publication.

Data Limitations
This information is somewhat limited because it is compiled on a statewide basis approximately every five years. When data on quantities of water withdrawn are only displayed for every fifth year, anomalies may exist for a given year, which could lead to an incorrect interpretation. If a given year has above or below normal precipitation (extremely wet or dry), or has an event like a hurricane, the water use value will most likely be skewed for that year. In addition, the data used to calculate this in formation are not always based on actual meter readings but reflect consumptive use permit files, monthly operating reports, direct contacts, advanced modeling, and other indirect methods.

Data Analysis
Fresh ground water withdrawals have increased steadily since 1965. In this same time period the population in Florida’s coastal counties has increased as well. Since 1965 ground water usage has steadily increased from 1,399.49 million gallons per day (m gd) to 2,855.52 mgd in 1990, a 104 percent increase. The use of surface water has fluctuated during the period of record, with the greatest use of surface water occurring in 1975 when 2,139.71 mgd were withdrawn.

			Total Fresh Water Withdrawals by Source

	    Year	GroundWater(MGD)	SurfaceWater(MGD)	TotalWithdrawal(MGD)
	    1965	    1399.49		     1458.17			2857.66
	    1970	    1784.63		     1474.59			3259.22
	    1975	    1911.98		     2139.71			4051.69
	    1980	    2344.55		     1882.57			4227.12
	    1985	    2550.22		     1611.74			4161.96
	    1990	    2855.52		     2011.47			4866.99