U.S. Geological Survey

Programs in Florida, 1999

The safety, health, and economic 

well-being of Florida’s citizens are important to the U.S. Geological Survey 

(USGS), which is involved in waterrelated, geologic, biological, land use, and 

mapping issues in many parts of the State. 

The USGS office in Tallahassee acts as the 

liaison for all studies conducted by USGS 

scientists in Florida. Water resources 

activities are conducted not only from the 

office in Tallahassee, but also from offices 

in Miami, Tampa, and Altamonte Springs 

(Orlando). Scientists in these offices 

investigate surface water, ground water 

and water quality in Florida, working in 

cooperation with other Federal, State and 

local agencies and organizations. 

The USGS Center for Coastal Geology and Regional Marine Studies was 

established in St. Petersburg in 1988, in 

cooperation with the University of South 

Florida. The Center conducts a wide variety of research on mineral resources and 

on coastal and regional marine problems, 

including coastal erosion, climate change, 

wetlands deterioration, and coastal pollution. A USGS mapping office is located in 

St. Petersburg. Also, the Earth Science 

Information Center (ESIC) in Tallahassee 

provides USGS information to customers 

and directs inquiries to the appropriate 

USGS office or State agency on earth 

science topics, particularly those related 

to cartography, geography, aerial photography, and digital data. Biologists at the 

USGS Florida Caribbean Science Center, 

located in Gainesville, conduct biological 

and ecosystem studies in Florida, Puerto 

Rico, and the Virgin Islands.

South Florida 

Ecosystem Studies

 Development of south Florida, 

including more than 1,400 miles of canals 

and 100 water-control structures, has 

contributed to a number of environmental 

problems. These problems include loss of 

soil, nutrient enrichment, contamination 

by pesticides, mercury accumulation in 

the biota, fragmentation of landscape, loss 

of wetlands and wetland functions, widespread invasion by exotic species, increasingly frequent algal blooms in coastal 

waters, seagrass die off, and declines in 

commercial and recreational fisheries.

A consensus emerged among Federal 

and State agencies and environmental 

groups that south Florida and the Everglades should be restored, to the extent 

possible, to hydrologic patterns similar to 

those of the original system. A Federal 

Task Force, chaired by the Department of 

the Interior (DOI), was formed in 1993 to 

oversee restoration. The USGS, the science agency of DOI, carries out many of 

the scientific activities needed to support 

restoration through the Integrated Natural 

Resources Science (INATURES) program, 

funding a diverse group of projects (fig. 1). 

Research is well underway, and in some 

cases is nearing completion. Following are 

the major tasks of the program:











































Tampa

Miami

Orlando

Brunswick

Savannah

Jacksonville

Tallahassee

SOUTH

CAROLINA

GEORGIA

FLORIDA G u l f o f

M e x i c o

A t l a n t i c O c e a n

Florida Bay

Florida Keys

Lake

Okeechobee

Everglades



0

0

50 MILES

50 KILOMETERS

GEORGIA–FLORIDA

 NAWQA

EXPLANATION

SOUTH FLORIDA NAWQA

SOUTH FLORIDA 

 ECOSYSTEM PROGRAM

Figure 1. Study areas of the Georgia-Florida 

Coastal Plain National Water-Quality 

Assessment (NAWQA) Program, the South 

Florida NAWQA Program, and the South 

Florida Ecosystem Program.

• To study the history of the ecosystem to 

determine pre-development (last few 

hundred years) climatic and environmental conditions in south Florida.

• To monitor biologic, cartographic, geologic, and hydrologic parameters over 

a long period of time (fig. 2).

• To conduct regional and site-specific 

multidisciplinary studies to gather 

background information.

• To conduct research on the biological and 

chemical processes that affect and 

control the cycling of nutrients, sulfur, 

mercury, and other contaminants.

• To develop and apply robust models to 

sheetflow, ground-water movement, 

evapotranspiration in different vegetation communities, and ecological 

interactions of key animal species.

• To prepare topical synthesis documents to 

analyze, summarize, and integrate 

USGS results, and describe the relevance of this research to management 

issues. The USGS web site describing 

South Florida Ecosystem studies can be 

found at: 

http://sofia.usgs.gov

The Suwannee River Basin - 

Water Resources and

Wetland Habitats

The ground- and surface-water 

resources of the lower Suwannee River 

basin (fig. 3) provide a variety of important benefits to north-central Florida. 

Although these resources have not been 

highly developed, demands are likely to 

increase from users within the basin, from 

within the Suwannee River Water 

Figure 2. USGS hydrologists sampling 

plants in the Everglades.

U.S. Department of the Interior n U.S. Geological Survey


Management District (SRWMD), and 

possibly from more populous areas of 

Florida. The SRWMD entered into a 

cooperative program with the USGS to 

study factors affecting water resources in 

the basin. Current activities include interpretive studies of surface- and groundwater interactions, and of the relation 

between wetland habitats and flow characteristics in the River. Ground-water and 

surface-water interactions in the Suwannee River basin are complex because of 

the karstic hydrologic conditions in the 

basin. Evaluating the effects of increased 

development in and near the lower 

Suwannee River basin requires an understanding of the dynamics of water 

exchanges between the lower Suwannee 

River, its tributaries, and the Floridan 

aquifer system. USGS hydrologists are 

developing computer-based models to 

simulate ground- and surface-water interactions. Environmental isotopes and age 

dating techniques are being used to determine the sources and chronology of 

nitrate contamination of springs in the 

basin. Also, an effort is underway to 

determine the relation between sources of 

nitrate in spring waters and changes in 

land-use patterns over the past 50 years.

Wetlands protection is an important 

goal of the SRWMD in setting minimum 

flows and levels on the Suwannee River; 

however, little is known about the water 

requirements of the river wetlands. The 

wetland study includes field work to identify vegetation and soil types in the floodplain, determine land-surface elevations, 

and monitor hydrologic conditions. Analyses and interpretations using map coverGulf

of

Mexico

Atlantic Ocean

Suwannee GEORGIA

River

basin

FLORIDA

Figure 3. Study area of the Suwannee 

River Basin project.

ages on a geographic information system 

(GIS), calculations to determine habitat 

areas, and analyses of long-term groundwater and surface-water records are also 

being conducted.

Environmental 

Contaminants and their 

Effects on Wildlife

More than 1,000 new chemicals are 

released into the environment each year, 

resulting in a growing potential for health 

risks. Increasing evidence suggests that 

exposure to some of these chemicals, 

called endocrine disrupters, can adversely 

affect the immune, reproductive, and 

endocrine systems of wildlife by interfering with natural hormones. The USGS is 

investigating the effects that these chemicals may have on wildlife species. 

Because waterways are the ultimate recipients of agricultural and industrial contaminants, aquatic animals often serve as 

sentinels or early indicators of environmental stress.

Field and laboratory studies are 

underway to examine the effects of herbicides, papermill effluent, and sublethal 

doses of mercury on largemouth bass. 

Results of these studies suggest that a 

variety of structurally diverse pollutants 

can alter sex steroid hormone levels, 

which could lead to reproductive impairment and population declines. USGS scientists are exploring environmental 

factors related to massive juvenile alligator mortality in Lake Apopka, and the 

effect of contaminants on various mussel 

species in their early stages of development. Findings suggest that mussels in 

early stages of development, or offspring 

of exposed females, may be particularly 

sensitive to the toxic effects of certain 

contaminants. USGS work 

will be expanded to learn 

more about the mechanisms 

of hormone actions and clarify the direct and multigenerational effects of 

contaminant exposure.

Florida Keys Coral 

Reefs

The USGS has conducted a series of geophysical surveys on the marine 

shelf, covering about onehalf of the Florida Keys 

National Marine Sanctuary. 

Information from the survey 

is being used to map the geology of the 

Keys, reef track, and shelf margin during 

approximately the last 10,000 years. Florida Keys reef growth began approximately 

6,000 years ago, when rising sea levels 

flooded the high-and-dry south Florida 

platform. Florida’s corals grow fast 

enough to have easily kept pace with the 

known rate of sea-level rise during the 

past 6,000 years; however, less than 1 percent of the reefs actually did keep pace, 

implying periodic coral deaths. Carbon-14 

age-dating methods are being used to 

determine the major periods of reef 

demise and regrowth, which may lead to 

finding a cause of the coral deaths. 

The USGS, in conjunction with the 

University of South Florida, will study 

African dust to determine its possible role 

in the periodic death of corals and coral 

reef organisms. Coral mortality became 

apparent in the 1970’s and is increasing at 

alarming rates. This marked increase in 

coral deaths appears to parallel the well 

documented rise in desertification in 

Africa (beginning in the 1970’s) and aerosol transport across the Atlantic Ocean. 

African dust contains xenobiotics, such as 

spores and bacteria, that have likely contributed to coral reef mortalities throughout the Caribbean basin.

Lake Studies

More than 7,800 lakes cover an area 

of about 3,600 square miles, or about 

6 percent of Florida. More than half the 

lakes occur on the sandy ridges of the central peninsula and are typically of sinkhole 

origin. Because of the mantle of permeable sands, ground-water flow systems 

predominate over surface drainage 

(fig. 4), making the central lakes district 

an important area of recharge to the upper 

Floridan aquifer system, the principal 









RECHARGE

SURFICIAL AQUIFER SYSTEM

CONFINING UNIT

UPPER FLORIDAN AQUIFER

DIRECTION OF GROUND-WATER MOVEMENT

WATER

TABLE

RAINFALL

Figure 4. Generalized cross section showing ground-water 

flow and hydrogeology at a Florida ridge lake.


potable water supply for the State. The 

integral connection between lake and 

ground-water hydrology in Florida presents many challenges to lake managers 

attempting to maintain acceptable ranges 

of lake-water levels and prevent deterioration of water quality in lakes from residential and agricultural development. 

Since 1995, USGS scientists in 

Tampa, in cooperation with the Southwest 

Florida and St. Johns River Water 

Management Districts and the Florida 

Department of Environmental Protection, 

have conducted studies addressing different aspects of lake hydrology. Ground 

water fluxes to lakes are being quantified 

using models that simulate saturated and 

variably-saturated ground-water flow in 

lake basins. Ground-water exchange with 

10 lakes was estimated using water budget and geochemical tracer approaches. 

Another study used nitrogen isotopes to 

identify sources of nitrate in the shallow 

ground water around lake basins. In the 

lake district north of Tampa Bay, the 

USGS is evaluating the effects on groundwater exchange and lake-water quality of 

augmenting lake levels with water from 

the Upper Floridan aquifer.

Regional-scale, multi-lake studies are 

underway to estimate ground-water 

inflow and historical lake-level fluctuations. Geologists at the USGS office in 

St.Petersburg recently used digital highresolution seismic systems to collect geophysical data from 30 lakes in north-central Florida. Analysis of seismic profiles 

for each lake showed that central Florida 

lake development follows four sequential 

stages to maturity. Seismic profiles were 

also used to locate possible breaches in 

the confining layer that maintains water 

levels in the lakes.

Water Quality

National Water Quality Assessment 

(NAWQA) Program studies are being 

conducted in three areas of Florida: 1) the 

Apalachicola River basin in the panhandle 

of Florida, 2) the Georgia-Florida Coastal 

Plain (fig.1), which includes south-central 

Georgia and north-central Florida, and 3) 

the south Florida area, which covers about 

19,500 square miles (fig. 1). This section 

focuses on results of the south Florida 

study.

A retrospective analysis of historical 

water quality data in south Florida indicates that fertilizer is a major source of 

nitrogen and phosphorus. Estimated 

annual nitrogen loads in south Florida are 

highest in outflows from the Caloosahatchee River basin and the major Palm 

Beach canals, and lowest in outflows from 

parts of the Big Cypress basin. Estimated 

annual phosphorus loads from the Peace 

River are the highest in the study unit. 

Annual phosphorus loads from the 

Caloosahatchee River and major Palm 

Beach canals are also high compared to 

other parts of south Florida.

Results of the 3-year intensive sampling program in south Florida show that 

nutrient concentrations vary widely both 

seasonally and spatially in response to 

human and natural influences. The most 

frequently detected pesticides in surface 

waters are atrazine, metachlor, and 

simazine; chlorinated hydrocarbon insecticides and PCB’s were detected in fish 

and bottom sediments. In 1995, DDT 

compounds were detected in 25 of 27 fish 

samples, sometimes in concentrations 

comparable to those detected in fish in the 

early 1970’s. 

Ecological studies in south Florida 

were completed to determine the abundance and diversity of fish, invertebrates, 

and algae. The effects of habitat alteration 

on animal and plant communities are particularly interesting in south Florida 

because the predevelopment patterns of 

water movement and storage have been 

altered extensively. An assessment of 

ground-water quality in south Florida 

focused on the potential influence of land 

uses such as commercial, light residential, 

and citrus and winter vegetable farming.

Water Use and Supply

The population of Florida increased 

by 7.4 million people (110 percent) 

between 1970-95. Data collected by the 

USGS, in cooperation with the Florida 

Department of Environmental Protection 

and water management districts, indicate 

that over this same period, freshwater 

withdrawals increased nearly 29 percent 

and saline water withdrawals increased 

13 percent. Between1990-95, however, 

Florida’s freshwater withdrawals 

decreased by about 4 percent, due in part 

to conservation and more efficient irrigation systems. 

Orange County is an area which has 

experienced tremendous population 

growth and urbanization since 1968. Agricultural land use (primarily citrus) has 

decreased from 67,000 to 10,000 acres 

between 1960-95. Ground-water withdrawals have nearly tripled in the past 30 

years, and the amount of impervious 

ground cover associated with urbanization 

has increased significantly. A study is currently underway to update information on 

the surface- and ground-water hydrology 

and water quality in Orange County, with 

particular emphasis on changes and trends 

since the early to mid-1960s. Specific 

concerns include the effects of groundwater withdrawals on water levels and 

wetland viability, of urbanization on the 

natural regimes of streamflow, and of land 

use on surface- and ground-water quality.

In Duval County, ground-water withdrawals from the Floridan aquifer system, 

the major source of water supply, 

increased from about 127 to about 145 

million gallons per day between 1965-95, 

resulting in a decline of 4 to 9 inches per 

year in the ground-water level. Concomitant with the drop in ground-water level 

has been an increase in chloride concentration (salty or brackish water), especially in eastern Duval County. Data 

collected in a 4-year study by the USGS, 

in cooperation with the City of Jacksonville and the St. Johns River Water Management District, indicate that the 

Fernandina permeable zone, the deepest 

zone of the Floridan aquifer system, is 

likely the source of the brackish well 

water in Duval County.

Manatee Population 

Research

The endangered manatee is one of the 

most unique and best known Florida animals (fig. 5), with major U.S. populations 

occurring along both coasts of Florida. 

Findings from continuing USGS research 

on the manatee have helped wildlife managers restore populations of this herbivorous marine mammal.

USGS biologists are conducting longterm studies on the manatee’s life history, 

population dynamics, and ecological 

requirements, and have pioneered several 

important tools, including a computerized 

photo-identification catalog and a radiotag assembly for tracking manatees by satFigure 5. Manatee in Florida waters.


USGS State representative

Florida District Office:

District Chief, USGS

227 N. Bronough St., Ste. 3015

Tallahassee, FL 32301

 850-942-9500, FAX: 850-942-9521

E-mail: FLinfo@usgs.gov

 Florida Subdistrict Offices:

Altamonte Springs, 407-865-7575

Miami, 305-717-5800

Tampa, 813-884-9336

USGS Center for Coastal Geology and

Regional Marine Studies:

600 Fourth St. South

St. Petersburg, FL 33701

727-803-8747

Florida-Caribbean Science Center

USGS-BRD

7920 N.W. 71st Street

Gainesville, FL 32653

352-378-8181

USGS Earth Science Info. Ctr:

Florida Resources & Environmental

Analysis Center

Florida State University

C2200 University Center

Tallahassee, FL 32306-4015

850-644-5447

Additional earth science

information can be found by

accessing the USGS Home Page

on the World Wide Web at

http://www.usgs.gov

For more information on

all USGS reports and products

(including maps, images,

and computerized data), call

1-800-USA-MAPS

Studies are underway to better understand the nesting habits of threatened loggerhead sea turtles on northwest Florida 

beaches, the inshore developmental and 

foraging habitat of the endangered 

Kemp’s Ridley sea turtle, and the effects 

of erosion on shorebird nesting and foraging habitat.

Cooperative Mapping 

Programs in Florida

For the past 8 years, the USGS and 

the Florida Department of Environmental 

Protection (FDEP) have been involved in 

a cooperative program to produce and 

maintain a digital base map for the State. 

This program is active in producing new 

image products, revising existing digital 

data categories, and revising existing 

1:24,000-scale maps. The USGS and 

FDEP signed a new Joint Funding Agreement in September 1998 for the collection 

of color-infrared aerial photographs to 

produce digital orthophoto quadrangles 

(computer-generated images of aerial photographs having the geometric qualities of 

maps). The Florida digital base map, 

which consists of transportation, hydrography, and boundary data layers, is being 

revised. Also, the USGS is updating 40 of 

Florida’s most popular 1:24,000-scale 

topographic maps. Through the National 

Cooperative Geologic Mapping Program, 

the Florida Geological Survey is funded to 

conduct geologic mapping projects 

designed to aid in resolution of groundwater protection, waste disposal siting, mineral resource identification, and land-use 

planning issues. 

ellite. Radio-tracking data are used to 

determine patterns of movement and habitat which are needed by management 

agencies to develop protection strategies. 

Scientists are studying manatee feeding 

habits as well as seagrass ecology in highuse manatee areas. Other USGS projects 

examine manatee population and the 

long-term, post-release success of manatees rehabilitated in captivity.

The USGS is also investigating the 

effects on manatees of eliminating industrial warm-water discharges, which help 

keep manatees warm in cold weather. This 

could result in changes in their distribution pattern and potentially influence their 

fitness and survival.

Coastal Ecosystem 

Dynamics

Coastal dynamics and erosion play a 

critical role in the conservation of Florida’s habitats and the plants and animals 

which rely on these habitats for survival. 

Scientists from the USGS Florida Cooperative Fish and Wildlife Research Unit, in 

collaboration with the Archie Carr Center 

for Sea Turtle Research at Eglin Air Force 

Base, the U.S. Fish and Wildlife Service, 

and several volunteer programs, are evaluating the effects of this dynamic environment on coastal fauna. A rise in sea-level 

alters coastlines and, subsequently, 

reduces or changes coastal habitats of loggerhead sea turtles and shorebirds. Some 

beaches in the Florida Panhandle lose 

more than 35 feet of sand per year, due 

especially to hurricanes. Vehicular traffic, 

coastal construction, and recreational 

boating further disturb coastal habitats. 

USGS office locations

Ochopee

Altamonte

Springs

Fort

Myers

Gainesville

Homestead

Jacksonville

Miami

Ocala

St. Petersburg

Tallahassee

Tampa

West

Palm

Beach

The USGS has 386

employees in Florida

The material in this 

document will soon be 

printed as fact sheet 

FS-010-99.

U.S. Geological Survey 

Open File Report 99-196

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