Prepared in cooperation with Volusia County The Water Cycle in Volusia County

Earth’s water is always in motion. The water cycle, also known as the hydrologic cycle, describes the continuous movement of water on, above, and below the Earth’s surface (fig. 1). This fact sheet provides information about Evapotranspiration how much water moves into and out of Volusia County, and where Rainfall it is stored. It also illustrates the Seepage from land surface to seasonal variation in water groundwater Groundwater and Surface-water quantity and movement using Outflow data from some of the hydrologic Groundwater seepage data collection sites in or near and spring discharge to land Volusia County (fig. 2). surface

Where is the water and how does it move in Volusia County? Figure 1. Major components of the water cycle.

Basic Concepts Most of the water in Volusia County Irrigation water that is not used by the is stored in three types of places—the plants seeps (percolates) into the ground Water that comes from the clouds in atmosphere (where water occurs in as recharge to the aquifers. Residents of the form of rain is known as precipitation. water vapor and droplets); surface-water Volusia County also use water pumped Water from the clouds falls to the Earth features such as lakes, wetlands, and from the aquifers for drinking water and and runs downhill into streams and lakes streams; and in underground reservoirs for household activities such as cleaning, as surface runoff. Some of this runoff known as the aquifers. The amounts of bathing, and flushing the toilet. Some of percolates into the soil and deep into the water in these three individual places are this water ends up as wastewater and is ground to be stored in the aquifer. Water constantly changing as water moves from treated in septic tanks or, more com- travels from the aquifer through the one place to another. monly, is discharged into sewers that springs back up to surface streams or to Human activity affects the move- transport the wastewater to wastewater the ocean. Water transpires from plants ment of water between the three distinct treatment plants. Septic-tank drainage and trees and evaporates from the Earth’s storage places. For example, some people seeps back into the ground as does treated surface and the ocean, returning to the use water from lakes, streams, or aqui- wastewater that is put into percolation atmosphere. Together these two processes fers for irrigating lawns and crops, or in ponds or sprayed onto the land surface at are called evapotranspiration, or ET. The industrial activities such as generation some wastewater treatment plants. How- water vapor from ET condenses to form of electricity. Irrigation water is used ever, in most coastal communities and clouds which produce precipitation that by grass and other plants during photo- near the St. Johns River, treated waste- falls back to the earth. This cycle of the synthesis. Some of the water taken up water is discharged directly into rivers or never ending movement of water on the by plants is returned to the atmosphere estuaries and flows from the county. Earth is called the water cycle. through the process of transpiration.

U.S. Department of the Interior Printed on recycled paper Fact Sheet 2009-3004 U.S. Geological Survey October 2009 81°30’ 81°00’ Water does not only move from one storage place to another. It is also in motion as streamflow on the land surface Atlantic Ocean and as groundwater flow through the

29°30’ aquifers beneath the land surface. This Volusia Crescent County motion is driven by gravity, as the natural City 95 behavior of water is to “flow downhill”; Gulf of that is, from locations with higher water M idd Mexico L le i levels to those with lower water levels. t H Creek t l a e w

H C PUTNAM COUNTY r Most streams in Volusia County begin

a e w e VOLUSIA COUNTY k within the county and flow into the Halifax ATLANTIC OCEAN Tomoka coastal estuaries, the St. Johns River, FLAGLER COUNTY River or Flagler County (fig. 2). Likewise, VOLUSIA COUNTY Holly Hill Daytona the flow of groundwater is mostly from Tiger Beach Bay Volusia County to the areas with lower Canal River St. water levels, such as the St. Johns River,

Deep Creek De Leon the coastal estuaries, the Atlantic Ocean, Springs and parts of surrounding counties. Little F

LAKE COUNTY De Leon

MARION COUNTY John’s ce C groundwater flows into Volusia County. Springs pru ree S k New Smyrna Thus, most of the water in Volusia River Beach County, both surface water and ground- 29°00’ Deland water, is of “local” origin, as it ultimately Lyonia

F 4 Blue Preserve results from the rain that falls directly on Springs the county.

Deep Of course the St. Johns River, on the western edge of Volusia County, drains Lake Creek Monroe Cow Creek 95 parts of Volusia County and also a large area to the south of Volusia County. The Sanford BREVARD COUNTY Lake St. Johns River is not considered in the Harney water budget because flow in this river is along the edge of the county rather than through it. EXPLANATION Kennedy MAJOR DRAINAGE DIVIDE SEMINOLE Space Center LakeF ApopkaSPRING COUNTY Storage of Water in the Atmosphere RAIN GAGE ORANGE COUNTY RiverIndian EVAPOTRANSPIRATION STATION There is always some water in the STREAM GAGING STATION atmosphere. Clouds are, of course, the visible condensation of atmospheric 28°30’ 0 5 10 MILES water, but even clear skies contain some 0 5 10 KILOMETERS water—water in particles that are just too small to be seen. The total amount of atmospheric Figure 2. Surface drainage features and locations of hydrologic data stations. water vapor in a vertical column of air (often called the precipitable water, or PW) is measured daily by the National

3 Weather Service with radiosondes (weather balloons). The highest daily MINIMUM AVERAGE water-vapor content measured at the MAXIMUM Kennedy Space Center radiosonde station (about 20 miles southeast of Volu- 2 Figure 3. Total daily water- sia County) between 1983 to 2005 would vapor content by month, be equivalent to a water depth of about 1983-2005 (data furnished 2.6 in. (inches) on the Earth’s surface by NOAA, from radiosonde (fig. 3). This is less than the amount of

IN INCHES 1 station at Kennedy Space rainfall that can be produced from a sin- Center). gle thunderstorm in just a few minutes! Thunderstorms often produce amounts of rain that exceed the water-vapor content TOTAL DAILY WATER-VAPOR CONTENT, WATER-VAPOR DAILY TOTAL of the overlying atmosphere. This excess 0 J FMAMJJASOND of rainfall over water-vapor content can 1983-2005 occur because colliding air currents can 10,000

1,000 Figure 5. Annual water budget for Volusia County 100 (adapted from Rutledge, 1985). All quantities except rainfall are outflow from the 10 county, and are in inches

WATER STORAGE, IN INCHES WATER over the entire county. 1 ATMOSPHERE LAKES AQUIFERS

EXPLANATION RAINFALL–53 inches Figure 4. Estimated average water storage in Volusia EVAPOTRANSPIRATION–39 inches County. (Amount of storage is equivalent to depth of water STREAMFLOW–11 inches over the entire surface of Volusia County. Each horizontal SPRING AND FLOWING WELL DISCHARGE–2.3 inches GROUNDWATER FLOW–0.7 inches line represents 10 times more water than the line below it). bring additional water vapor from (Fernald and Purdum, 1998), there are not aquifers. A more detailed description surrounding areas into the storm. a few lakes of sinkhole origin which of the ground-water system for Volusia The average daily atmospheric could be more than 100 ft in depth. For County has been provided by several water-vapor content, based on data for example, the assumption that an average investigators, including Knochenmus and 1983 through 2005, is equivalent to only lake water depth is 10 ft suggests that the Beard (1971), Rutledge (1985), Kimrey about 1.3 in. This is a relatively small total amount of water contained in (1990), and Williams (2006). amount of water as compared to the all Volusia County lakes would be about Most of the groundwater in Volusia amounts of water contained in surface- 35 billion cubic feet, which would be County is contained within the Floridan water and groundwater storage. Although equivalent to a water depth of about aquifer system. Estimates of the amounts the atmosphere may not be a great store- 12 in. distributed over the entire county. of water contained in this aquifer can house of water, it is the superhighway Other surface-water features were be made by multiplying the volume used to move large quantities of water not included in this estimate of surface- (lateral area multiplied by thickness) by from one location to another. water storage on the land surface because the porosity of the rock. Porosity is a the areas or depths of water have not measure of the relative volume of empty Storage of Water on the Land Surface been documented. These include smaller space within the rock that can be Lakes are the most important lakes, wetland areas that contain water at occupied by water. Porosity of the vessels for surface-water storage in least part of the year, and the water that is Floridan aquifer system is variable; Volusia County. There are at least flowing in streams. however, an approximate average 239 lakes in Volusia County that are porosity can be used to estimate how Storage of Water in the Ground 10 acres or more in size (Florida Board of much water is contained within the Conservation, 1969). These lakes have a Underground water is stored in an system. Scientists used an average of combined area of about 79,300 acres, of aquifer, which is a layer of rock, sand, 25 percent porosity in studies of ground- which the vast majority is linked to the or other earthen material through which water flow in the upper part of the St. Johns River that forms the western water can flow. There are two types of Floridan aquifer system (Davis, 1996), boundary of Volusia County. The total aquifers underlying Volusia County. The and thus estimated that the Floridan surface area of Volusia County is about surficial aquifer system extends from the aquifer system is about 25 percent water. 768,000 acres. Therefore, the percent- land surface to depths of 50 to 100 ft, This volume of groundwater is equiva- age of the land surface that is covered by and is composed mostly of sand, shell, lent to an astonishing 500 ft overlying lakes is about 10 percent. For the lakes and clay. Underlying the surficial aquifer the entire area of Volusia County. Much that are not part of the St. Johns River, system is the Floridan aquifer system, of this groundwater, especially near the coast and along the St. Johns River, is this coverage is only about 1.3 percent. which is composed mostly of limestone. brackish; that is, it contains salt and is not The amount of water contained in The two aquifers are separated in parts suitable for drinking. lakes depends on the depth of the water of the county by a layer of silt and clay A comparison of the amounts of in the lakes. Lake depths have not been which significantly slows the flow of water stored in the atmosphere, on the documented for many of Volusia County water from one aquifer to another. The surface, and beneath the ground in Volu- lakes, so only an estimate of total lake Floridan aquifer system extends to a sia County indicates that groundwater is water volume can be made. While most depth of about 2,000 ft in Volusia County. by far the largest storage place for water lakes in Florida are shallow and aver- Underlying the Floridan aquifer are rocks (fig. 4). Groundwater probably accounts age between 7 and 20 ft (feet) in depth that are impermeable and, therefore, are 10 60

8 55

6 50

4

45

ANNUAL TOTAL, IN INCHES ANNUAL TOTAL, 2

MONTHLY TOTAL, IN INCHES TOTAL, MONTHLY

40 DAYTONA DELAND SANFORD CRESCENT MEAN CITY (4 sites) 0 J FMAMJJASOND NOAA STATIONS 1923-2006

Figure 6. Average rainfall at Daytona, DeLand, Sanford, and Figure 7. Average monthly rainfall at DeLand, Florida, Crescent City NOAA stations, 1923-2006. 1923-2006. for more than 99 percent of the water rainfall events. In summer it is not Evapotranspiration in Volusia County. By comparison, the uncommon for a thunderstorm to drench Evapotranspiration can be estimated amount of water stored in the atmosphere a particular neighborhood, while by a water-budget analysis, in which ET is relatively insignificant. However, as leaving areas a block or two away dry. is the difference between the amount the transporter of virtually all water into On an annual or longer basis, rainfall is of rainfall and the amount of surface the county, the atmosphere becomes a less variable from place to place, though water and groundwater outflow (amount very important feature, even though the differences do occur. For example, the of water flowing away from Volusia atmospheric layer over Volusia County average rainfall for the entire period of County). Evapotranspiration accounts for contains very little water at any one time. record common to all four stations (1923 the largest outflow of water from Volusia

The Water Budget: Moving Water In and Out of Volusia County

In the following discussion, the through 2006) ranged from about 56 in. County and is estimated to be about water budget shown in figure 5 is derived at DeLand, to about 49 in. at Daytona 39 in/yr (fig. 5). from Rutledge (1985). Although this Beach (fig. 6). The reason for these Evapotranspiration studies have water budget was developed more than differences from location to location in been conducted at two sites in Volusia 20 years ago, it still is representative of or around Volusia County is not clearly County using instrumentation that mea- current conditions (2009). More recent understood. sures the amount of water vapor moving data on rainfall, streamflow, and evapo- There is a definite seasonal pattern upward to the atmosphere. These studies transpiration are used to illustrate sea- to rainfall in Volusia County. Summers also provide a range of the ET that can sonal and location-to-location variability are typically wet, although there can occur within the county. In 2002, one of these components of the water cycle. be dry periods of several days or a study at the Lyonia Preserve week or more between storms. Winters (fig. 2) determined that ET from a Rainfall are typically dry, and an entire month or forested upland area was 42 in/yr. In Rainfall provides practically all more can sometimes pass with no rain- contrast, ET from a wetland near the of the inflow of water to Volusia County fall. This seasonal pattern is evident forested upland area was much higher, (fig. 5). Based on four long-term stations, from the average monthly totals for and was estimated to be 59 in/yr for the rainfall is estimated to average about rainfall at DeLand (fig. 7). Monthly year (Knowles and others, 2005). Another 53 in/yr (inches per year) over the entire total rainfall is generally between 2 and study in a cypress and pine forest near the county. However, rainfall can vary from 4 in. during all months except for June streamgaging station on Tiger Bay Canal place to place. Most of us have witnessed through September, when it is between (fig. 2) measured an ET rate of about the short-term variability of individual 7 and a little more than 8 in. 38 in/yr in 1998-99 (Sumner, 2001).

25 RAINFALL–At Lyonia Preserve EVAPOTRANSPIRATION–From uplands at Lyonia Preserve 20 20

15 15

10 10

5 5

MONTHLY TOTAL, IN INCHES TOTAL, MONTHLY

MONTHLY TOTAL, IN INCHES TOTAL, MONTHLY

0 0 J FMAMJJASOND J FMAMJJASOND 2002 1977-2006

Figure 8. Monthly rainfall and evapotranspiration at Lyonia Figure 9. Average monthly total streamflow, Tomoka Preserve, 2002 (data from Knowles and others, 2005). River near Holly Hill, Florida, 1977-2006.

Generally, ET rates are related to water County. Another basin includes Deep (fig. 5). Most of this groundwater availability at the land surface and within Creek (north and south tributaries), Cow outflow is from springs and flowing wells the upper soil layers, and are greatest in Creek, and other tributaries, and drains where groundwater is being discharged lakes and wetland areas, and lowest in the into the St. John River to the west. The from the Floridan aquifer system to well-drained sandy ridge areas. other basin drains seaward and contains surface streams. The two principal Changes in the amount of evapo- Tomoka River, Spruce Creek, and Tiger springs in Volusia County, Blue Spring transpiration on a daily or seasonal basis Bay Canal. Streamflows in Volusia and DeLeon Spring, account for about tend to be smaller than the variation in County have been measured regularly by 2.0 in/yr. Rutledge (1985) estimated that

Streams transport much more water out of Volusia County than they bring into the county.

rainfall. Extended periods of no rainfall the USGS at the streamgaging stations two small springs near can last for several weeks in the winter shown in figure 2, with records beginning discharged an additional 0.1 in/yr, and and spring, but ET occurs nearly every in 1950 or earlier for some streams. that flowing wells discharged about day. Also, unlike rainfall, extremes in There is a distinct seasonal pattern 0.2 in/yr. However, most of these flow- daily or monthly ET are relatively not to streamflow, with lowest flows occur- ing wells have since been plugged as dramatic. For example, at the Lyonia ring at the end of the spring dry period a result of the abandoned artesian well Preserve, monthly rainfall in 2002 ranged and the highest flows occurring at the end plugging project of the St. Johns River from about 0.9 in. to more than 22 in., of the summer wet period. Streamflow for Water Management District. while ET ranged from about 1.8 to 5.6 in. the Tomoka River depicts this seasonal- There is also subsurface movement for the same period (fig. 8). ity, with the 30-year average streamflow of groundwater through the Floridan ranging from 2.1 in. during May to about aquifer system into and out of the county. Streamflow 20 in. during September (fig. 9). This subsurface flow at the county Streams transport much more water boundaries cannot be directly observed Groundwater out of the county than they bring into or easily estimated. Estimates by the county. Streamflow accounts for the Groundwater movement takes more Rutledge (1985) indicate that about second largest outflow of water from water out of the county than it brings into 0.8 in. of groundwater flows into the Volusia County, or about 11 in/yr (fig. 5). the county. However, this groundwater county from adjacent counties, and that There are three major streamflow basins outflow accounts for a relatively small about 1.5 in. flows from the county, for a in Volusia County (fig. 2). One basin amount of water, compared to the other net subsurface outflow of about contains Little Haw Creek and Middle components of the county water budget, 0.7 in/yr. Haw Creek and drains north to Flagler and is estimated to be about 3 in/yr

The Human Role small in comparison with the 53 in/yr 2001-2003: U.S. Geological Survey that the county receives by rainfall. Scientific Investigations Report Does human use of water affect 2005-5178, 82 p. the water budget of Volusia County as References Cited a whole? Water is pumped from the Marella, R.L., 2004, Water withdrawals, Floridan aquifer system for many uses, Davis, H., 1996, Hydrogeologic investi- use, discharge, and trends in Florida, including drinking-water supply, crop gation and simulation of groundwater 2000: U.S. Geological Survey Scien- and lawn irrigation, industrial uses, and flow in the Upper Floridan aquifer of tific Investigation Report 2004-5151, recreational purposes. In 2005, an aver- north-central Florida and southwestern 50 p. age of about 77 Mgal/d (million gal- Georgia and delineation of contribut- lons a day) was withdrawn from Volusia ing areas for selected City of Tallahas- Marella, R.L., 2008, Water use in Florida, County aquifers (Marella, 2008). This see, Florida, water-supply wells: U.S. 2005 and trends 1950–2005: rate of water flow, which is equivalent to Geological Survey Water-Resources U.S. Geological Survey Fact filling about 115 Olympic-sized swim- Investigations Report 95-4296, 56 p. Sheet 2008-3080, 6 p. ming pools each day, could cover the National Oceanic and Atmospheric entire Volusia County land surface to a Fernald, E.A., and Purdum, E.D., eds., Administration, 2007, Cape depth of about 1.3 in. in a 1-year period. 1998, Water Resources Atlas of Kennedy, Florida: 1950 – 2005 XMR/ Thus, human usage of water is relatively Florida: Institute of Science and Public COF Surface-300 MB Precipitable small in comparison to the 53 in/yr that Affairs, Tallahassee, Florida State Water: accessed May 28, 2008 at the county receives by rainfall. University, 312 p. http://www.crh.noaa.gov/unr/include/ Some of this water returns to the pw.php?sid=xmr ground after use as seepage from irrigated Florida Board of Conservation, 1969, Florida lakes part III Gazetteer: 145 p. lawns and crops, septic tank drainage, or Rutledge, A.T., 1985, Ground-water treated wastewater through land applica- Kimrey, J.O., 1990, Potential for ground- hydrology of Volusia County, Florida, tion and percolation ponds associated water development in central Volusia with emphasis on occurrence and with wastewater treatment plants. Some County, Florida: U.S. Geological movement of brackish water: U.S. of the water used for irrigation (about Survey Water-Resources Investigations Geological Survey Water-Resources 20 Mgal/d in 2005 according to Marella, Report 90-4010, 31 p. Investigations Report 84-4309, 29 p. 2008) returns to the atmosphere as ET.

Where will Volusia County get additional water?

Some treated wastewater is discharged Knochenmus, D.D., and Beard, M.E., Sumner, D.M., 2001, Evapotranspira- to the St. Johns River, the , 1971, Evaluation of the quantity and tion from a cypress and pine forest and the , thus exiting Volusia quality of the water resources of Volu- subjected to natural fires in Volu- County. Wastewater treatment plants sia County, Florida: Florida Bureau of sia County, Florida, 1998-99: U.S. serving DeLand and the coastal commu- Geology Report of Investigations 57, Geological Survey Water-Resources nities of Daytona Beach, New Smyrna 59 p. Investigations Report 01-4245, 56 p. Beach, and others discharged about 15 Mgal/d to rivers in 2000 (Marella, Knowles, L.K., Jr., Phelps, G.G., Williams, Stanley, 2006, Simulation of 2004.) This is equivalent to about Kinnaman, S.L., and German, E.R., the effects of groundwater with- 0.3 in/yr for the Volusia County water 2005, Hydrologic response in karstic- drawals from the Floridan aquifer budget. Thus, the amount of wastewater ridge wetlands to rainfall and evapo- system in Volusia County and vicinity: that is discharged from the county is transpiration, central Florida, St. Johns River Water Management District Technical Publication SJ2006- 4, 218 p.

U.S. Department of the Interior For more information contact: KEN SALAZAR, Secretary U.S. Geological Survey By Edward R. German Central Florida Research Park U.S. Geological Survey 12703 Research Parkway Suzette M. Kimball, Acting Director Orlando, Florida 32826 (407) 803-5531