STATE OF FLORIDA
STATE BOARD OF CONSERVATION
DIVISION OF GEOLOGY
FLORIDA GEOLOGICAL SURVEY
Robert O. Vernon, Director
REPORT OF INVESTIGATIONS NO. 37
GEOLOGY AND GROUND-WATER RESOURCES
OF GLADES AND HENDRY
COUNTIES, FLORIDA
By
Howard Klein, M. C. Schroeder, and W. F. Lichtler
U. S. Geological Survey
Prepared by the
UNITED STATES GEOLOGICAL SURVEY
in cooperation with the
FLORIDA GEOLOGICAL SURVEY
and the
CENTRAL AND SOUTHERN FLORIDA FLOOD CONTROL DISTRICT
Tallahassee
1964
AGRI-
FLORIDA STATE BOARD cULTRM
F LIBRARy
OF
CONSERVATION
FARRIS BRYANT
Governor
TOM ADAMS
Secretary of State
J. EDWIN LARSON
Treasurer
THOMAS D. BAILEY
Superintendent of Public Instruction
RICHARD ERVIN
Attorney General
RAY E. GREEN
Comptroller
DOYLE CONNER
Commissioner of Agriculture
W. RANDOLPH HODGES
Director
LETTER OF TRANSMITTAL
florida C eological Survey
Callabassee
October 10, 1964
Honorable Farris Bryant, Chairman
Florida State Board of Conservation
Tallahassee, Florida
Dear Governor Bryant:
The Division of Geology is publishing, as Florida Geological
Survey Report of Investigations No. 37, a report on the "Geology
and Ground-Water Resources of Glades and Hendry Counties,
Florida," which was prepared by Howard Klein, M. C. Schroeder,
and W. F. Lichtler, as a part of a cooperative program between
the U. S. Geological Survey and the Florida Geological Survey.
Both Glades and Hendry counties obtain water from the Flori-
dan aquifer, generally by artesian flow, and from several shallow
aquifers. Recharge of the artesian aquifer occurs over these
counties and in Polk County. The report is a continuation of a
series, which is designed ultimately to present the geologic and
hydrologic facts of all of the State. Only in this way, can the State
be guaranteed a conservative and adequate development of its
water and associated resources.
Respectfully yours,
Robert O. Vernon
Director and State Geologist
Completed manuscript received
August 7, 1963
Published for the Florida Geological Survey
By E. O. Painter Printing Company
DeLand, Florida
1964
iv
CONTENTS
Abstract _.._ -- -____.--------......... -------------- ----.. --. --- 1
Introduction ---___. -._-----.__...................___..___--_..---- 2
Purpose and scope of investigation _------------ 2
Acknowledgments 3------------- ---_--------- 3
Previous investigations---- -_--------.__ ---------3.------ 3
Geography __--___ ._...__ --- ----------- ___ ----.-----.-----_ --- 5
Location of area 5~
General land features and drainage ....__.__...--- -------- ----- 5
Everglades _---.-----_--------------_------_------------- 5
Sandy Flatlands -_---------------.---------------------.---- -----. 7
Big Cypress Swamp .......-----------.-_ _-------.---------- 7
Drainage ..---~_....- ...- ------------------_.------ ------ 9
Climate ---..------_ ......__. .....---- --- ------------- 10
Development and growth of area ------.-- ------------ ------ 11
Geologic formations and water-bearing characteristics -------12
Eocene Series ---_------------------------------ ------ 12
Lake City Limestone ----------__--------------------------- 14
Avon Park Limestone .-----------_.--.__---- ----- ------- 16
Ocala Group .---_-------_ ---------------- -.. -----. .--------- ---------- 18
Oligocene Series -__----- --------__-------- 20
Suwannee Limestone .....----------_.-----_------ ---20
Miocene Series .-------.----- ---- __-- -_ ----- ----- 21
Tampa Formation _----____----_-___ ---- ---. -----21
Hawthorn Formation -.___-- __-------- 22
Tamiami Formation ---_- ...-- __.....-- ------- 24
Pliocene Series __---..-. -_---_--------------------- 25
Caloosahatchee Marl ___ __-_ __ ----. 25
Pleistocene Series -------------------------------26
Anastasia Formation 26
Fort Thompson Formation ___--- --27
Terrace deposits ---.-- -_-------- 29
Recent Series ____-_- --- 30
Lake Flirt Marl -.------.------- ._------------ ----30
Organic soils -- ------------------ 30
Ground water ..------....----.. --. _---- --__-- --. -- ----------- ----- ------ 31
Occurrence and movement __-_____ _31
Floridan aquifer -32
Piezometric surface ---- --------- ----- 39
Recharge 39
Discharge ___- --------------------------------------41
Discharge 41
Water-level fluctuations ----------------------------- 41
Shallow aquifers --------------- ----____---------- 43
Water-level fluctuations -----------------45
Recharge and discharge --- ----------- 47
Hydraulic characteristics ----------------------------------- ----49
Quality of water ---...... --....---.----- -----------58
Hardness __---------------------------- 62
Total dissolved solids _- 62
Specific conductance -__ -__ 67
Hydrogen-ion concentration (pH) 68
Iron (Fe) 68
Calcium (Ca) and magnesium (Mg) ____ 69
Sodium (Na) and potassium (K) 69
Bicarbonate (HCO3) 70
Sulfate (SO4) 70
Chloride (Cl) 70
Fluoride (F) 74
Silica (SiO,) 74
Nitrate (NO3) --------------------- 75
Hydrogen sulfide (H1S) -- ----- ----75
Salt-water contamination ____ 76
Direct encroachment _______- 76
Upward leakage ___--_-----76
Incomplete flushing ___80
Utilization of ground water _______ 81
Irrigation _81
Municipal supplies 82
Other uses __ 83
Summary 83
References __-_______ 85
Well logs -----___ 88
ILLUSTRATIONS
Figure Page
1 Location of Glades and Hendry counties 4
2 Glades and Hendry counties showing physiographic regions
and the directions of surface drainage __ __--_- 6
3 Approximate extent of Pleistocene terraces in Glades and
Hendry counties ______ 8
4 Glades and Hendry counties showing the locations of geo-
logic sections and included wells _____ 15
5 South-north geologic section A-A' through Glades and
Hendry counties ________ 16
6 South-north geologic section B-B' through Glades and Hendry
counties 17
7 West-east geologic section C-C' through Hendry County 18
8 South-north geologic section D-D' along the western shore
of Lake Okeechobee __ ____ 19
9 Glades County showing the locations of wells 33
10 Hendry County showing the locations of wells __34
11 LaBelle and vicinity showing the locations of wells 35
12 Clewiston and vicinity showing the locations of wells 36
13 Graphs showing distribution of flow in selected wells in
Glades and Hendry counties _____--___ __ 38
14 Glades and Hendry counties showing the configuration of the
piezometric surface of the Floridan aquifer, 1958 ----- __--------__- 40
15 Profiles of the piezometric surface of the Floridan aquifer
in Glades and Hendry counties, 1958 ___43
16 Hydrographs of wells 3 and 5 in Hendry County and well
131 in Collier County ________ 46
17 Hydrographs of well 234 and the Caloosahatchee River at
LaBelle compared with rainfall for the period 1953-54 48
18 Coefficients of transmissibility and storage determined at
test sites in Glades, Hendry, and Collier counties in shallow
aquifers ___________ _~_ ______.___. 50
19 Composite of semilogarithmic distance-drawdown graphs of
five aquifer tests _51
20 Time-drawdown graphs of water levels in observation wells,
and sketches showing locations of wells used in aquifer tests 52
21 Semilogarithmic time-drawdown graphs of four observation
wells in test area E __-_ .... --__ __ -------------.-.._.....__. 56
22 Semilogarithmic time-drawdown graphs of observation wells
in test areas B and D _--- --____----_-- _--_- __----_.___ 57
23 Graphs showing drawdowns expected at different distances
from a well pumped at selected rates in each of six test areas 59
24 Graph showing the relation between specific conductance
and total dissolved solids in water samples from Glades and
Hendry counties ____ 68
25 Graph showing the suitability of ground water for irriga-
tion (after Wilcox 1948, p. 25-26) 71
26 Glades and Hendry counties showing the chloride content of
water samples from wells tapping the Floridan aquifer,
1952-53, 1958 ____ ___ 72
27 Glades County showing the chloride content of water samples
from wells tapping shallow aquifers, 1952-53 73
28 Part of eastern Glades County showing the chloride content
of water samples from wells tapping shallow aquifers,
1952-53, 1959 74
29 Hendry county showing the chloride content of water samples
from wells tapping shallow aquifers, 1952-53, 1958 75
30 Clewiston area showing the chloride content of water samples
from wells tapping the shallow aquifer, 1952-53 ---....-. -__-- 76
31 Part of northwestern Hendry County showing the chloride
content of water samples from wells tapping deep and shal-
low aquifers, 1952-53, 1958 _77
32 LaBelle showing the chloride content of water samples
from wells tapping the shallow aquifer, 1952-53 ___ 79
33 LaBelle showing (by isochlor lines) areas of equal chloride
content of water from the shallow aquifer, 1952-53 -- ____ 80
TABLES
Table Page
1 Average temperature (oF) at Moore Haven and LaBelle,
1935-56 _____ ---------_______ 10
2 Rainfall in inches at Moore Haven and LaBelle, 1935-56 __ 11
3 Geologic formations in Glades and Hendry counties 13
4 Water-level and flow measurements made during drilling of
well 22, Glades County 36
5 Coefficients of transmissibility, storage and leakage in Glades,
Hendry and eastern Collier counties 54
6 Analyses of water from wells in Glades and Hendry counties 60
7 Partial analyses of water from wells in Glades and Hendry
counties -- ~--_______ 63
8 Records of wells in Glades and Hendry counties 102
GEOLOGY AND GROUND-WATER RESOURCES
OF GLADES AND HENDRY
COUNTIES, FLORIDA
By
Howard Klein, M. C. Schroeder, and W. F. Lichtler
ABSTRACT
Ground water in Glades and Hendry counties is obtained from
the Floridan aquifer, which yields water by artesian flow in most
areas of the two counties, and from several shallow aquifers.
Highly permeable parts of the Floridan aquifer are limestones
of the Tampa Formation' (early Miocene) and of the Ocala Group
and the Avon Park Limestone (Eocene). The yields of wells pene-
trating the Floridan aquifer usually exceed 200 gpm (gallons per
minute). Except in the central and northwestern parts of Glades
County, wells deeper than 800 feet yield highly mineralized water.
The upper part of the Floridan aquifer (Tampa and Hawthorn
Formations) yields relatively fresh water in the vicinity of LaBelle,
Hendry County, and in all of Glades County except in the area
adjacent to Lake Okeechobee. In the remainder of Hendry County,
the artesian water contains more than 700 ppm (parts per million)
of chloride.
The artesian aquifer in Glades and Hendry counties is recharged
primarily from the piezometric high in Polk County in central
Florida. The piezometric surface of the aquifer is highest in north-
western Glades County and southeastern Hendry County. The
high-pressure area in southeastern Hendry County may be a
residual mound resulting from a large number of uncontrolled
flowing wells to the northwest. This uncontrolled discharge over
a long period has resulted in an overall decline in artesian pressure
in the counties. Discharge from the aquifer is mainly through
flowing wells.
'The nomenclature of the rock units conform to the usages of the Florida
Geological Survey and also, except for the Tampa Formation and the Ocala
Group and its subdivisions, with those of the U. S. Geological Survey which
regards the Tampa as the Tampa Limestone and the Ocala Group as two
formations-the Ocala Limestone and the Inglis Limestone.
The Ocala Group as used by the Florida Geological Survey includes the
Crystal River, Williston, and Inglis Formations.
FLORIDA GEOLOGICAL SURVEY
Shallow ground water is obtained from wells ranging in depth
from 20 to 300 feet, which penetrate limestone and shell beds in
the Tamiami Formation (upper Miocene) and limestone and pebble
beds in the upper part of the Hawthorn Formation. The quality
of the water from these aquifers generally is superior to that from
the Floridan aquifer. Yields of 6-inch wells tapping shallow aquifers
range from about 200 to 1,400 gpm. The most prolific shallow
aquifer is a highly permeable limestone section of the Tamiami
Formation which underlies central and southern Hendry County.
Recharge to shallow aquifers is by local rainfall, by downward seep-
age from overlying sediments, and by southward underflow from
Highlands County, where pebble beds and limestone of the
Hawthorn Formation occur at shallow depth. Discharge from the
shallow aquifers is chiefly by evapotranspiration and by pumping
for irrigation of truck crops.
Quantitative tests on wells penetrating the shallow aquifers
show that the coefficient of transmissibility ranges from 70,000
gpd ft (gallons per day per foot) to 1,070,000 gpd/ft, and that the
coefficient of storage ranges from 0.00015 to 0.0014. A method for
forecasting the results of continued pumping during an extensive
drought is illustrated in the report.
INTRODUCTION
PURPOSE AND SCOPE OF INVESTIGATION
The extensive and expanding utilization of ground water for
domestic, municipal, and irrigation supplies in Glades and Hendry
counties, Florida, has created the problem of locating and preserving
satisfactory water supplies. The expansion of agriculture increases
the demand for irrigation water, a large part of which must come
from ground-water reservoirs. The development and growth of
communities are in part dependent upon the availability of adequate
supplies of potable water. This report describes the geology and
appraises the ground-water resources of Glades and Hendry
counties. It contains information on the location, availability, and
quality of the ground-water resources in the two counties, and
furnishes basic data that can be used in flood control and water
conservation.
Fieldwork for the investigation was begun late in 1952 by the
U. S. Geological Survey in cooperation with the Florida Geological
Survey and the Central and Southern Florida Flood Control District,
REPORT OF INVESTIGATIONS No. 37
but was suspended between 1953 and 1958 because of more urgent
commitments. Work was resumed in June 1958 and was completed
by September 1958.
The investigation was under the supervision of N. D. Hoy,
district geologist, and M. I. Rorabaugh, district engineer, of the
U. S. Geological Survey.
ACKNOWLEDGMENTS
The investigation was aided by data contributed by local resi-
dents, property owners, farmers, and ranchers. These data in-
cluded the locations of wells, their total depth, casing depth, and
yield, and in a few cases information on the quality of the water.
The generosity of local residents in permitting the sampling of wells
and measuring of water levels is greatly appreciated. The writers
are especially indebted to the following well drillers and concerns:
Roy Messer, LaBelle; Chester Beeles and James Drawdy, Arcadia;
C. D. Cannon, Palmetto; the B. & D. Drilling Co., and James
Whatley of Immokalee; and Miller Bros., Fort Myers. They granted
permission to collect rock cuttings and water samples, take flow
readings, and measure water levels during the drilling of wells
and, in addition, they furnished geologic and hydrologic informa-
tion. Flow-velocity measurements in flowing artesian wells were
made through the cooperation of C. C. Carlton, Arcadia, and M. K.
Wheeler, LaBelle.
The Florida Geological Survey furnished logs of a few shallow
and deep wells in the area. The Corps of Engineers, U. S. Army,
Jacksonville District, furnished charts of water stages of the
Caloosahatchee River.
Mollusks listed in the well logs were identified by Julia Gardner
and F. S. MacNeil of the Paleontology and Stratigraphy Branch,
U. S. Geological Survey, Washington, and by personnel of the
Florida Geological Survey, Tallahassee.
PREVIOUS INVESTIGATION
References to the geology and ground-water resources of Glades
and Hendry counties have been made in several reports published
by the Florida Geological Survey and the U. S. Geological Survey.
Brief descriptions of surface and subsurface geology and water-
well data in the Glades-Hendry area were presented by Matson and
Clapp (1909), Sellards (1912, 1919), Matson and Sanford (1913),
and Cooke and Mossom (1929). Stringfield (1936) discussed the
FLORIDA GEOLOGICAL SURVEY
geology and hydrology of the principal artesian aquifer in Florida.
Cooke (1945) and Parker and Cooke (1944) discussed the surface
and shallow subsurface geology in the Caloosahatchee River and
Lake Okeechobee areas. Water-quality and water-level data were
given by Stringfield (1936), and the chemical analyses of 17
ground-water samples were published by Black and Brown (1951).
Schroeder and Klein (1954) described and interpreted the shallow
geology of eastern Hendry County from a series of core borings.
Parker and others (1955) gave generalized information on the
geology of Glades and Hendry counties and presented a few specific
data concerning the quality of the water from the Floridan aquifer
and the shallow aquifers. DuBar (1958) described in detail the
geology along the Caloosahatchee River and discussed the strati-
graphic relationship of the Caloosahatchee Marl and the Fort
Figure 1. Location of Glades and Hendry counties.
REPORT OF INVESTIGATIONS No. 37
Thompson Formation. The following U. S. Geological Survey Water-
Supply Papers contain records of ground-water levels in Hendry
County: 987, 1017, 1024, 1072, 1097, 1127, 1157, 1166, 1192, 1222,
1266, 1322, and 1405.
GEOGRAPHY
LOCATION OF AREA
Glades and Hendry counties are in the central part of southern
Florida and constitute an area of approximately 2,000 square miles.
Glades County, the smaller, lies north of Hendry County and
borders the western shore of Lake Okeechobee (fig. 1).
GENERAL LAND FEATURES AND DRAINAGE
Three general physiographic units are included in Glades and
Hendry counties and are classified with respect to land-surface
altitude, surface-mantling material, and types of vegetation. The
general units listed by Parker and Cooke (1944, p. 38-53) are the
Everglades, the Sandy Flatlands, and the Big Cypress Swamp (fig.
2). Davis (1943, p. 40-50) subdivided the Sandy Flatlands and
used the designation Western Flatlands for the area west of Lake
Okeechobee. Also, he specifically designated the area in north-
eastern Glades County as the Istokpoga-Indian Prairie Basin. This
unit extends northwestward into Highlands County.
EVERGLADES
The Everglades covers an area along the eastern boundary of
Hendry County and reaches a maximum width of about 6 miles in
the northeastern part of the county (fig. 2). In Glades County the
Everglades borders part of the southwestern shore of Lake
Okeechobee and extends to Lake Hicpochee. The boundary between
the Everglades and other physiographic units is indefinite, but may
be placed where sedges and sawgrass give way to true grasses,
pinelands, and cypress trees. Places of slightly higher altitude
support the growth of trees and shrubs because of better aeration
of the soil.
The soil of the Everglades is predominantly organic, but it
contains some fine sand. The .organic soil is composed almost en-
tirely of peat in eastern Hendry County, where the maximum thick-
|ness is 8 feet. Farther north, in southeastern Glades County, the
FLORIDA GEOLOGICAL SURVEY
HIGHLANDS COUNTY
LAKE
COLLIER COUNTY
EXPLANATION
SANDY FLATLANDS
EVERGLADES
BIG CYPRESS SWAMP
APPROXIMATE DRAINAGE DIVIDE
DIRECTION OF SURFICIAL DRAINAGE
SCALE IN MILES
2 0 2 4 6 8 10
COLLIER COUNTY
81Oo'
Figure 2. Glades and Hendry counties showing physiographic regions and
the directions of surface drainage.
REPORT OF INVESTIGATIONS NO. 37
sand content gradually increases until the soil loses its organic
character. In eastern Hendry County the Everglades peat and muck
overlies marl or an eroded marly limestone surface (Parker and
Cooke, 1944, p. 48) at an altitude of about 8 feet above msl (mean
sea level). The surface altitude of the Everglades is everywhere
less than 25 feet above msl.
SANDY FLATLANDS
The Sandy Flatlands is the largest physiographic unit in Glades
and Hendry counties. In Glades County it includes all but the area
east of Lake Hicpochee, and in Hendry County all but the eastern
and southern edges (fig. 2). The Sandy Flatlands extends north-
ward into Highlands County, westward to the Gulf of Mexico and
southward into Collier County. A minor subdivision in northeastern
Glades County is the southward extension of the Istokpoga-Indian
Prairie Basin.
The sands were deposited as marine terraces during late
Pleistocene time, when sea level fluctuated from more than 70 feet
to less than 25 feet above sea level.
The surface altitude in the Sandy Flatlands ranges from about
10 feet to more than 70 feet above msl. The highest sandy surfaces,
which are in western Glades County and north of Fisheating Creek,
were deposited by the Penholoway sea of Pleistocene time, which
stood 42 feet to more than 70 feet above present sea level. The
wide reentrant in the Penholoway terrace in the northwestern part
of Glades County (fig. 3) resulted from erosion by Fisheating Creek
after the recession of the Penholoway sea. Figure 3 (from Parker
and others, 1955, pl. 10) shows the approximate extent of Pleisto-
cene terrace surfaces in Glades and Hendry counties.
The Talbot terrace slopes gently toward the Caloosahatchee
River and Lake Okeechobee and surface altitudes range from about
42 to 30 feet above msl (fig. 3). An area in western Hendry County,
where altitudes are comparable to the Talbot terrace, was referred
to by Parker (1955, p. 139) as Immokalee Island. The Pamlico
terrace, where altitudes do not exceed 30 feet above msl, is the
area between the Talbot terrace and the Everglades.
BIG CYPRESS SWAMP
The Big Cypress Swamp includes a large part of southern
Hendry County. The land-surface altitude in this area is lower
than that of the Sandy Flatlands, but is usually slightly higher than
FLORIDA GEOLOGICAL SURVEY
LAKE
OKEECHOBEE
Figure 3. Approximate extent of Pleistocene terraces in Glades and Hendry
counties.
EXPLANATION
PENHOLOWAY TERRACE
fmn
TALBOT TERRACE
PAMLICO TERRACE
REPORT OF INVESTIGATIONS No. 37
the Everglades. Except in small areas of southwestern Hendry
County, altitudes are less than 25 feet above msl.
The soil of the Big Cypress Swamp in Hendry County is chiefly
sand grading to loam near the northern boundary of Collier
County. At the edges of the Big Cypress Swamp the soils merge
with the sand of the higher Sandy Flatlands and the peat and
muck of the Everglades.
The surface of the Big Cypress Swamp is flat and marked by
many small, high hammock areas. The hammocks support bunch
grass, palmettos, and pines, and stand out from the swampy region
where low cypress, sedges, and marsh plants predominate.
DRAINAGE
Most of Glades and Hendry counties lie within the Fisheating
Creek and the Caloosahatchee River watersheds. These and other
drainage features are shown in figure 2. Drainage of the northern
part of Glades County is by Fisheating Creek, which flows south-
ward from the high sandy ridge areas of Highlands County into
Glades County and eastward into Lake Okeechobee. Because of the
low gradient in the eastern reaches of Fisheating Creek, drainage
is sluggish and much of this area in eastern Glades County is
flooded during rainy seasons. The northeastern part of the county
is drained chiefly by the Kissimmee River, the Harney Pond Canal,
and the Indian Prairie Canal. Drainage in the remainder of Glades
County and the western part of Hendry County is by the Caloosa-
hatchee River. The divide that separates the Caloosahatchee River
and the Fisheating Creek drainage basins trends east-southeast
across south-central Glades County. The Devil's Garden marshy
area in central and southern Hendry County drains sluggishly to
the west into the Okaloacoochee Slough, which in turn normally
drains northward into the lower Sandy Flatlands, and southward
into the Big Cypress Swamp. During high-water periods, drainage
from Devil's Garden may occur in all directions.
The discharge of the Caloosahatchee River depends upon the
water stage of Lake Okeechobee. During low lake stages the
spillways and gates at Ortona Lock are closed and flow in the
river is greatly reduced. However, during wet periods the gates
are opened and the discharge of the river is increased many times.
The stage of the Caloosahatchee River is affected by the Gulf of
Mexico tides as far upstream as the Ortona Lock.
Before drainage and water control were in effect in the Ever-
glades and Lake Okeechobee areas, the Lake Flirt basin and Lake
FLORIDA GEOLOGICAL SURVEY
Hicpochee were fed by overflow from Lake Okeechobee. Much of
the Everglades and the areas adjacent to Lake Okeechobee and the
Caloosahatchee River were flooded during rainy seasons and for a
considerable period afterward. The construction of the levee along
the southern rim of Lake Okeechobee and the improvement of the
channel of the Caloosahatchee River after the floods of 1928 resulted
in a decrease in the overall area affected by periodic flooding.
The Devil's Garden and the Okaloacoochee Slough in central
and western Hendry County are the largest remaining marshy
areas (fig. 2). Surface runoff throughout most of the 2-county
area is sluggish because of the flatness of the region. Rainfall
soaks into the sandy mantle of the flatlands, and when the ground
becomes saturated, wide shallow ponds and marshes form in large
areas.
CLIMATE
The climate of Glades and Hendry counties is subtropical and
the temperature rarely falls below freezing. Table 1 shows the
average monthly and yearly temperatures at Moore Haven and
La Belle. Table 2 shows the maximum, minimum, and average
monthly and yearly rainfall at the same stations. The average
annual rainfall for the period 1935-56, from U. S. Weather Bureau
records, is 49.83 inches at Moore Haven and 51.81 inches at LaBelle.
The maximum monthly rainfall at Moore Haven was 21.55 inches in
September 1948. The minimum of record occurred in 1956 when
only 30.94 inches of rain fell at Moore Haven. Rainfall is heaviest
during June through October and lightest during November through
February. The average monthly rainfall at the Moore Haven and
LaBelle stations is similar.
TABLE 1. Average Temperature (oF) at Moore Haven and LaBelle, 1935-56
Moore Haven LaBelle
January 64.00 64.2
February 64.5 64.4
March 67.5 68.0
April 72.0 72.5
May 75.9 76.5
June 79.5 79.9
July 80.9 81.3
August 81.4 81.7
September 80.3 80.6
October 75.9 75.6
November 68.9 68.5
December 67.4 65.1
Year 73.2 73.2
REPORT OF INVESTIGATIONS NO. 37
TABLE 2. Rainfall, in Inches, at Moore Haven and LaBelle, 1935-56
Moore Haven LaBelle
Max. Min. Average Max. Min. Average
January 5.73 0.05 1.45 4.07 0.00 1.48
February 5.02 .03 1.68 5.46 .03 1.84
March 8.73 .03 2.17 8.84 .01 2.35
April 5.64 .21 3.03 7.71 .65 3.05
May 11.96 1.13 4.39 9.24 .71 3.12
June 15.02 3.61 7.25 19.32 3.33 9.20
July 16.13 2.99 8.27 15.14 5.11 8.46
August 12.51 2.39 6.61 13.90 2.21 7.66
September 21.55 2.23 8.08 18.51 2.92 7.87
October 11.11 .03 4.17 13.46 .31 4.21
November 5.47 .03 1.31 2.21 .18 1.26
December 6.46 .11 1.42 4.63 .08 1.31
Year 71.20 30.94 49.83 73.83 36.83 51.81
DEVELOPMENT AND GROWTH OF AREA
In 1950 the populations of Glades and Hendry counties were
2,199 and 6,051, respectively. Between 1940 and 1950 the popula-
tion of Glades County declined about 20 percent and that of Hendry
County increased more than 10 percent. The estimated populations
as of July 1958 were 3,100 for Glades County and 7,200 for Hendry
County. Most of the population is concentrated near Lake
Okeechobee. In 1950, Moore Haven, the Glades County seat, LaBelle,
the Hendry County seat, and Clewiston, had populations of 636,
945, and 2,499, respectively. The population of the area increases
in winter when migrant farmworkers move into the area for the
growing season. Only a small number of tourists visit these two
counties, mainly for fishing in Lake Okeechobee and hunting.
Agriculture is the predominant economic activity in both
counties, and the chief products are winter vegetables, sugarcane,
beef cattle, and dairy products. Green beans, lettuce, and sugarcane
are grown on the Everglades mucklands adjacent to Lake
Okeechobee; peppers, tomatoes, cucumbers, and watermelons are
the main crops raised on the sandy soils. A crop is grown every
year on the mucklands, but on the sandy soils the land is farmed
for only one or two seasons, owing to the spread of plant disease
and the rapid growth of Bermuda grass on the cultivated soil. The
land then usually is converted to improved pasture with a forage
cover of pangolia, carib, or other grass. Citrus is grown along the
Caloosahatchee River downstream from LaBelle. Dairy farms are
located near Clewiston, LaBelle, Moore Haven, and Lakeport. One
of the largest single-unit cane factories for producing raw sugar is
located south of Clewiston.
FLORIDA GEOLOGICAL SURVEY
GEOLOGIC FORMATIONS AND WATER-BEARING
CHARACTERISTICS
The main water-bearing rocks underlying Glades and Hendry
counties include consolidated and unconsolidated strata ranging in
age from Eocene to Recent. Rocks of middle Miocene age and
older yield water by natural flow, but the shallower, younger sedi-
ments yield water to wells in which the water levels normally are
below the land surface. The sediments form part of the southern
flank of the regional Ocala uplift (Vernon, 1951, p. 54-65), the
crest of which is in northern and north-central Florida. The beds
conform to the regional uplift in a subdued manner and dip gently
to the south. The general sequence of geologic formations under-
lying Glades and Hendry counties is shown in table 3. Rocks
deposited before the middle Miocene Epoch are composed almost
entirely of limestone, formed by the accumulation and cementation
of shell fragments and by chemical precipitation of calcium
carbonate in a marine environment. Younger materials are chiefly
plastics, deposited as an aggregate of sand, silt, and clay, with
shelly material scattered throughout.
The surface sediments in Glades and Hendry counties are of
Pleistocene and Recent age. Subsurface beds composed of im-
permeable clay and marl form a major part of the middle Miocene.
A limestone section occurs at the top of the Tampa Formation and
continues downward through Oligocene, Eocene, and Paleocene
rocks. According to Applin (1951, p. 6-7) the top of the Upper
Cretaceous rocks in Glades and Hendry counties occurs at depths
ranging from 4,500 to 6,000 feet. Oil is recovered from Lower
Cretaceous rocks at the Sunniland field (Collier County), near the
southwest corner of Hendry County, from a depth of about 11,500
feet.
The recognition and differentiation of the Tertiary formations
are of variable accuracy. In most samples macrofossils are not
present in sufficient quantities to make accurate determination of
the formation. In many cases no diagnostic fossils were present in
the drill cuttings, and lithologic differences were used to identify
the formations.
EOCENE SERIES
Rocks of the Eocene Series in Glades and Hendry counties are
chiefly limestones of different textures and permeability, and are
represented in ascending order by the Oldsmar Limestone, the Lake
TABLE 3. Geologic Formations in Glades and Hendry Counties
Estimated range
of thickness
Series Group Formationi (feet) Lithology and water-bearing properties
Recent Organic soils 0- 8 Peat and muck; water has high color.
Lake Flirt Marl 0- 8 Fresh-water marl, sandy muck, carbonaceous sand; of low permeability.
Terrace deposits 0- 15 Quartz sand; yields small quantities of water to sandpoint wells; water
is colored and high in iron content.
Pleistocene Fort Thompson Formation 0- 15 Alternating marine shell beds and fresh-water marl; generally of low
(contemporaneous with permeability except locally where it is solution riddled.
Anastasia)
Anastasia Formation 0- 15 Sand, marl, and shell beds; yields colored water to standpoint wells.
Pliocene Caloosahatchee Marl 0- 60 Shell, sand, and silt; shell beds yield water that in some areas is highly
mineralized.
Tamiami Formation 30-110 Sand, marl, shell beds, and limestone; limestone is fairly widespread and
yields large quantities of water for irrigation.
Hawthorn Formation 300-500 Clay marl, sand, gravel, and limestone; clay marl forms confining beds
Miocene for the Floridan aquifer; limestone at base forms upper part of the
Floridan aquifer; sand and gravel and limestone beds in upper part
yield water to wells.
Tampa Formation 15-100 Sandy limestone: yields water under artesian pressure; is part of the
Floridan aquifer.
Oligocene Suwannee Limestone 0-570
Ocala 150-800 Limestone and dolomite; yields water under artesian pressure, in many
areas highly mineralized; is part of the Floridan aquifer.
Eocene Avon Park Limestone 200-390 Limestone and dolomite; yields water under artesian pressure, highly
mineralized in much of the area; is part of the Floridan aquifer.
Lake City Limestone 800+ Crystalline dolomite, dolomitic limestone and chalky limestone; porous and
highly permeable; yields large quantities of highly mineralized water
in much of the area; is part of the Floridan aquifer.
1U. S. Geological Survey lists formations as follows: Luke Flirt Marl as Pleistocene and Recent; Ocala Group as Ocala Limestone and Inglis Lime-
stone; Tampa Formation as Tampa Limestone.
0
*U
---- --I- -- I--~-- -- -----I~---- -- L- __ __-II 1 1___11 _--____--------_-
FLORIDA GEOLOGICAL SURVEY
City Limestone, the Avon Park Limestone, and limestones of the
Ocala Group. The Oldsmar Limestone, the oldest formation of the
series, has not been penetrated by water wells in the two counties.
Cooke (1945, p. 40) states that the formation unconformably over-
lies rocks of Paleocene age. In most places in Florida the formations
of the Eocene Series can be differentiated only by a study of micro-
fossils. Figure 4 shows the locations of wells for which detailed
logs are available and also the locations of the geologic sections
shown in figures 5-8.
LAKE CITY LIMESTONE
The Lake City Limestone is the name applied by Applin and
Applin (1944, p. 1693) to the dark-brown chalky limestone of early
middle Eocene age penetrated between depths of 497 to 1,010 feet
in a well at Lake City, Columbia County. They give a thickness of
200 to 250 feet for the formation in peninsular Florida, and Cooke
(1945, p. 46) also estimates that the formation in southern Florida
ranges in thickness from 200 to 250 feet. The Lake City Limestone
beneath southern Florida is composed of brown, hard, crystalline
dolomite and dolomitic limestone, and cream-colored permeable
limestone. The general absence of appreciable plastic material and
the subsurface extent of the limestone indicates that Glades and
Hendry counties were located a considerable distance offshore at
the time of its deposition.
A large part of the fossil content of the Lake City Limestone
is Foraminifera. Applin and Jordan (1945, p. 131) list species that
they consider diagnostic of the formation. Vernon (1951, p. 92)
indicates that the Lake City Limestone may rest unconformably on
the Oldsmar Limestone and is unconformable with the overlying
Avon Park Limestone.
Bishop (1956, p. 113) estimates that 80 feet of the Lake City
Limestone was penetrated in well 22, in northeastern Glades County
(fig. 5). The only other known penetrations of this formation were
by deep oil-test wells. The geologic section A-A' shown in figure 5
indicates that the regional dip of the formation is southward.
The Lake City Limestone has good porosity, is highly permeable,
and is part of the Floridan aquifer. Bishop (1956, p. 18) states that
the Lake City Limestone, because of its high permeability, is a
highly productive part of the Floridan aquifer beneath Highlands
County. However, it yields highly mineralized water in most of
Glades and Hendry counties.
REPORT OF INVESTIGATIONS NO. 37
Figure 4. Glades and Hendry counties showing locations of geologic sections
and included wells.
FLORIDA GEOLOGICAL SURVEY
Figure 5. South-north geologic section A-A' through Glades and Hendry
counties.
AVON PARK LIMESTONE
Applin and Applin (1944, p. 1686-1687) gave the name Avon
Park Limestone to the highly microfossiliferous limestone in the
upper part of the late middle Eocene rocks which occur between
depths of 600 and 930 feet in a well drilled at Avon Park in Polk
County. Vernon (1951, p. 95-96) identified the Avon Park Lime-
stone at the surface in Citrus and Levy counties. The formation
underlies all of Glades and Hendry counties, increasing in thickness
to the southeast; it ranges from 200 feet in southern Highlands
County (Bishop, 1956, p. 14) to 390 feet in southern Hendry
County. The Avon Park Limestone is mainly a tan-to-white,
slightly porous, chalky limestone containing many microfossils;
part of the formation, however, is composed of brown, hard,
granular limestone and dolomitic limestone. The microfossils have
been described by Applin and Applin (1944), Applin and Jordan
(1945), and Cole (1942, 1944). Vernon (1951, p. 99) indicates
that the Avon Park Limestone is separated from older and younger
formations by erosional unconformities.
Cooke (1945, p. 51-52) states, "The Avon Park limestone was
deposited in an open ocean that received little sand or clay. The
REPORT OF INVESTIGATIONS No. 37 17
B R HENDRY COUNTY I GLADES COUNTY
D o(- t B-
B a
200 M M W 200
aj _j J
0 MSL ML
SMSL TAMIAM FORMAT -f----f..-- MSLO
-200 HAWTHORN FORMATION -200
.400 TA--PA--.F -400
TAMPA FORMATION
-600 -600
SUWANNEE LIMESTONE
--8oo00 -8oo
-1000 -I00&
OCALA GROUP
-1200 -1200
-1400 AVON PARK LIMESTONE -1400
-1600 -- -1600
-- FORMATION CONTACTS DASHED
ST WHEREINFERRED
S LAKE CITY LIMESTONE SCALE IN MILES
2 0 2 4 6 a
Figure 6. South-north geologic section B-B' through Glades and Hendry
counties.
entire Floridan Plateau was probably submerged, but the location
of the shore line is unknown." Vernon (1951, p. 97) states, "The
fauna of the Avon Park limestone ranges from a shallow-water
marine beach to only slightly deeper marine facies. The environ-
ments favorable for such deposits are shallow coastal bays,
beaches, and marine shelves where almost no plastic material was
being deposited." Vernon found in Polk County that the Avin
Park Limestone resembled a beach-type deposit, and in -the:-:
encircling area the limestone is a shallow-water marine deposit. It
seems likely that in Glades and Hendry counties the Avon Park
Limestone is mainly a shallow-water marine-shelf deposit.
The formation is an important component of the Floridan
aquifer and will yield water to flowing wells in most areas. In much
of Glades and Hendry counties the water is highly mineralized.
FLORIDA GEOLOGICAL SURVEY
C
200 <
0MSL
-200
-400
-600
-800
-1000
-1200
-1400
-1600
TAMPA FORMATION
-600 -600
HENDRY COUNTY
-- TAMIAMI lIOCENE
__ _-_ TIAMI FORMATION
HAWTHORN FORMATION
C'
200
MSLO
-200
-400
-600
-800
-1000
-1200
SUWANNEE
LIMESTONE
OGALA GROUP
AVON PARK
-
LIMESTONE
FORMATION CONTACTS DASHED
WHERE INFERRED
SCALE IN MILES
U 468
-1400
Figure 7. West-east geologic section C-C' through Hendry County.
OCALA GROUP
Cooke (1915, p. 117; 1945, p. 53) defined the Ocala as limestone
of Jackson age. Applin and Applin (1944, p. 1683-1685) and Applin
and Jordan (1945, p. 130) determined that the Ocala could be
differentiated into a lower and an upper unit. Vernon (1951, p. 115)
correlated the basal 80 feet of the Ocala Limestone of Cooke (1945,
p. 53-73) at the outcrop area in Citrus and Levy counties with
the Moodys Branch Formation of early Jackson age in Alabama.
By separating this basal part, to which he applied the name Moodys
Branch Formation, Vernon (1951, p. 156) restricted the Ocala
Limestone to beds of late Jackson age. He described the Moodys
Branch Formation in Florida as a marine, fossiliferous limestone
REPORT OF INVESTIGATIONS NO. 37
Figure 8. South-north geologic section D-D' along the western shore of Lake
Okeechobee.
composed of the camerinid-rich Williston Member at the top, and
the echinoid-rich Inglis Member at the base. The Ocala Limestone
of Cooke was raised to group rank by Puri (1953, p. 130), who
subdivided it into three formations as follows: the Crystal River
Formation, equivalent to Vernon's Ocala Limestone (restricted);
the Williston Formation, equivalent to the upper part of the Moodys
Branch Formation; and the Inglis Formation, equivalent to the
lower part of the Moodys Branch Formation.
Limestones of the Ocala Group range in thickness from about
150 feet to 390 feet and appear to thicken in a southwesterly
direction within Glades and Hendry counties. In general they are
cream-colored, soft and chalky, and in many places are composed
of a foraminiferal coquina. The lowermost part of the Ocala Group
is unconformable with the Avon Park Limestone. The top of the
Ocala is an eroded surface and, according to Cooke (1945, p:' 56)4,
the oldest outcropping rocks overlying it are those of the Mariannai
Limestone of middle Oligocene age in northwestern Florida. Cooke
(1945, p. 57) suggests that during the deposition of the Ocala
Group the shoreline was in Alabama and Georgia and that the
sea was open and fairly shallow. Vernon (1951, p. 57) seems to
agree with this concept, as he found some detrital, crossbedded
limestone in his Inglis Member.
FLORIDA GEOLOGICAL SURVEY
Bishop (1956, p. 23) states that the limestones of the Ocala
Group are not important units in the Floridan aquifer beneath
the ridge area of Highlands County. In Glades and Hendry
counties, however, they are fairly permeable and yield appreciable
amounts of water to wells penetrating the aquifer. These lime-
stones contain relatively salty water in most parts of the two
counties.
OLIGOCENE SERIES
Cooke (1945, p. 75) states, "The Oligocene series, as interpreted
by the United States Geological Survey, is divided into three parts.
The lowest, which includes the Red Bluff clay and the Forest Hill
sand of Mississippi, is not known to be represented in Florida. The
Marianna limestone and the overlying Byram limestone together
comprise the middle part to which the name Vicksburg group is
now restricted. The Suwannee limestone and its littoral equivalent,
the Flint River formation, are of late Oligocene age." The
Suwannee Limestone apparently is the only formation of Oligocene
age in Glades and Hendry counties.
SUWANNEE LIMESTONE
The name Suwannee Limestone was proposed by Cooke and
Mansfield (1936, p. 71) for the yellowish limestone exposed along
the Suwannee River in Hamilton and Suwannee counties, in
northern Florida. The formation includes all the beds lying below
the Tampa Formation and above the Byram Formation or older
beds. The definition is the same as that used by MacNeil (1944,
p. 1313-1318).
The Suwannee Limestone underlies all of Glades and Hendry
counties except an area in the northeastern part of Glades County.
The formation thickens from north to south and apparently from
east to west, and reaches a maximum thickness of about 570 feet
(fig. 5-7).
The distribution of Oligocene rocks in Florida indicates that
erosion prevailed over large areas during the Oligocene Epoch. The
sea that transgressed during the middle Oligocene Epoch deposited
the Marianna and Byram Formations in western Florida, but Glades
and Hendry counties probably were above sea level during early
and middle Oligocene time and limestone of the Ocala Group was
undergoing considerable erosion. It appears that the only time
Glades and Hendry counties were covered by Oligocene seas was
during deposition of the Suwannee Limestone.
REPORT OF INVESTIGATIONS NO. 37
The Suwannee Limestone is a white, finely porous limestone,
somewhat crystalline and partly dolomitized. It is moderately
permeable and yields artesian water to deep wells that penetrate
the Floridan aquifer; however, the water contained in the Suwannee
Limestone is brackish in most of Glades and Hendry counties.
MIOCENE SERIES
Cooke (1945, p. 109-111) recognized three divisions of the
Miocene which, in the Florida Peninsula, are represented by the
Tampa Formation (lower Miocene), Hawthorn Formation (middle
Miocene), and Duplin Marl. Puri (1953, p. 38-41) recognized three
divisions of the Miocene in the Florida Panhandle: Tampa Stage
(lower Miocene), the Alum Bluff Stage (middle Miocene), and the
Choctawhatchee Stage (upper Miocene). In southern Florida the
Miocene Series is represented by the Tampa Formation, the Haw-
thorn Formation, and the Tamiami Formation in ascending order.
TAMPA FORMATION
The Tampa Formation of this report refers to the sandy lime-
stone, of Miocene age, that lies above the Suwannee Limestone and
beneath the predominantly plastic beds of the Hawthorn Formation.
The Tampa Formation, which crops out in the vicinity of Tampa
Bay, was originally described by Johnson (1888) and Dall (1892).
The formation probably underlies all of Glades and Hendry
counties, but in northeastern Glades County it is very thin. It
gradually increases in thickness from 15 feet in northeastern Glades
County to about 190 feet in southern Hendry County. It is composed
of porous, highly permeable limestone, friable calcareous sandstone,
and a few beds of white chalky marl. Because of solution by
ground-water movement, fossils are preserved mainly as molds.
This solvent action has produced the very porous and permeable
zones within the formation.
The Tampa Formation overlies the Suwannee Limestone
unconformably. Puri (1953, p. 38) indicates that the Tampa is
unconformably overlain by the Hawthorn Formation and its
equivalents in western Florida. Some of the field studies of Cooke
(1945, p. 115) suggest that it may grade vertically upward into the
Hawthorn Formation. This gradational relationship may pertain
in Glades and Hendry counties.
The Tampa Formation is very permeable, and together with
the limestones of the lower part of the Hawthorn Formation
FLORIDA GEOLOGICAL SURVEY
furnishes most of the artesian water used in Glades and Hendry
counties.
HAWTHORN FORMATION
The Hawthorn Formation of this report is defined as beds
younger than the Tampa Formation and older than the upper
Miocene sediments. This is essentially the definition of Cooke
(1945, p. 44) and of Vernon (1951, p. 186-187). The Hawthorn
Formation underlies all of Glades and Hendry counties and ranges
in thickness from about 300 feet in southern Hendry County to
about 500 feet in northern Glades County.
The Hawthorn Formation is composed of light-green to greenish-
gray sandy marl, green and white plastic clay, finely crystalline
permeable limestone, silty sands, and quartz pebbles. These
sediments commonly contain small grains of phosphorite and
occasionally contain phosphate pebbles. The coarse sand and pebbles
occur in the beds near the top of the formation and the limestone
beds usually occur near the base. Sandy and clayey marls are the
predominant sediments of the Hawthorn Formation.
Puri (1953, p. 38-39) had indicated that in western Florida the
Hawthorn Formation and its equivalents overlie the Tampa Forma-
tion unconformably and underlie the upper Miocene sediments
unconformably. Cooke (1945, p. 145) also reports that the upper
Miocene beds overlie the Hawthorn plastics unconformably.
Lithologic and foraminiferal studies of cuttings from wells located
west and southeast of Glades and Hendry counties suggest that
the Tamiami Formation (upper Miocene) may overlie the Hawthorn
Formation conformably. The Hawthorn Formation probably is
early and middle Miocene in age.
The Hawthorn Formation, as examined from well cuttings in
Glades and Hendry counties, is apparently of marine origin. Bishop
(1956, p. 26) has found that the ridge area in Highlands County
is underlain by deltaic sediments containing sand, quartz pebbles,
phosphorite, mica, and kaolinite, which overlie typical marine marl
and clay of the Hawthorn Formation. The upper Miocene beds
appear to wedge out against these deltaic deposits on both flanks
of the ridge. The deposits probably are of late Hawthorn age and
apparently extend southward into Glades County in the vicinity
of U. S. Highway 27.
According to reports from well drillers, a gravelly bed occurs
in northeastern Glades County and extends southward into Hendry
County. It has been recognized in some of the wells for which
lithologic logs have been prepared. In well 4, west of Clewiston in
REPORT OF INVESTIGATIONS NO. 37
Hendry County, the gravel between 91 and 127 feet below the land
surface could be interpreted as the basal part of the Tamiami
Formation; however, the authors believe that it is part of the
Hawthorn Formation and is a southward extension of the ridge
deltaic deposits. Quartz pebbles also have been penetrated within
the Hawthorn Formation in a well on Marco Island, Collier County,
a well in Dade County near the Collier-Monroe County line, and a
well on Cape Sable in the Everglades National Park. Bishop (1956,
p. 27) also reports that quartz pebbles have been found in the
Hawthorn Formation- underlying the Bone Valley Formation
(Pliocene) in Polk County. Well drillers report that in Glades and
Hendry counties the gravels are usually isolated masses and are of
irregular thickness. These occurrences tend to substantiate the
fact that a delta tongue extended southward from Highlands County
during late Hawthorn time.
Glades and Hendry counties were submerged during early
Hawthorn time and the shoreline probably extended as far north
as the Ocala uplift, as suggested by Vernon (1951, p. 181-184).
Before the end of Hawthorn time a finger of a delta progressed
southward across Highlands County and the final frontal slope
formed near Venus (Highlands County). It is presumed that only
bottomset deltaic beds were deposited in Glades and Hendry
counties. The sea withdrew from most of Florida at the end of
Hawthorn time, but there is a possibility that all of southern
Florida may have been receiving continuous deposition during the
middle and late Miocene time, and the contact between the Haw-
thorn Formation and the Tamiami Formation may be conformable.
Local occurrences of gravel, thin limestone beds, and shell beds
in the upper part of the Hawthorn Formation form moderately
productive aquifers in an area about 5 miles west of Moore Haven
in Glades County, in an area north of the Devil's Garden in Hendry
County, and in the vicinity of LaBelle. Wells that penetrate
these aquifers range in depth from about 100 to 175 feet.
The limestone beds in the lower part of the Hawthorn Forma-
tion are fairly widespread and may form a hydrologic unit with
the underlying more permeable limestones of the Floridan aquifer.
The beds by themselves do not yield sufficient quantities of water
for most irrigation needs, and wells are generally drilled into one
or more of the underlying limestones. In most places, the clay
and marl of the Hawthorn Formation form the confining unit for
the Floridan aquifer; upward leakage through these materials is
small.
FLORIDA GEOLOGICAL SURVEY
TAMIAMI FORMATION
The Tamiami Formation, as redefined by Parker (1951, p. 823),
includes all upper Miocene deposits in southern Florida. The
Tamiami Formation underlies all of Glades and Hendry counties.
The deposition of sediments in Glades and Hendry counties
during Tamiami time probably was controlled by the southward
extension of the Hawthorn deltaic plastic materials which formed
a topographic high. In the western half of Glades and Hendry
counties and in Lee and Charlotte counties .the Hawthorn deltaics
occur at a higher altitude than the Hawthorn plastic sediments to
the east (fig. 7). Consequently, the overlying sediments of Tamiami
age in the western parts of the counties are thinner than those in
the eastern parts of the counties and probably do not exceed 80
feet in thickness (fig. 7). They are composed chiefly of fine and
medium sand, silt, marl, and lenses or thin beds of shells. These
sediments appear to be reworked Hawthorn deltaic deposits.
In much of the eastern part of Hendry County the Tamiami
Formation contains limestone that dips to the east and southeast.
Limestone in the Tamiami Formation is continuous and widespread
over an area exceeding 400 square miles. At the Collier-Hendry
County boundary, directly east of Immokalee, limestone occurs at
a depth of 22 feet below the land surface and extends to a depth of
at least 55 feet. This limestone layer presumably dips eastward
to a depth of about 90 feet in an area 8 miles east of the county
boundary, and to a depth of 120 feet in an area about 20 miles east
of the county line. The limestone wedges out 3 to 5 miles east of
Immokalee, and no shallow limestone beds are reported in the
immediate vicinity of Immokalee.
The Tamiami Formation differs in composition from shelly
marl to soft, silty, fossiliferous limestone in different localities. The
formation crops out locally along the Caloosahatchee River in
Glades and Hendry counties where it is a greenish-gray sandy
clay. DuBar (1958, p. 34) suggests that the Tamiami Formation
along the Caloosahatchee River reaches a maximum thickness of
at least 60 feet. Throughout Glades County and northern and
western Hendry County the Tamiami Formation is composed
chiefly of sand, marl, and shells.
In most of southern and eastern Hendry County the limestone
beds of the Tamiami Formation are highly permeable and yield
large quantities of water to relatively shallow irrigation wells.
In the remainder of Hendry County and in Glades County local
shell beds and lenses will yield moderate quantities of water to
REPORT OF INVESTIGATIONS NO. 37
domestic wells or small irrigation wells. Some shell beds in the
vicinity of LaBelle and the area bordering Lake Okeechobee yield
water of relatively high mineral content.
PLIOCENE SERIES
The Caloosahatchee Marl is the only formation of Pliocene age
recognized in southern Florida. Although there is some uncertainty
about the age of the Caloosahatchee Marl, the authors tentatively
are retaining it in the Pliocene. DuBar (1958, p. 35) assigned the
Caloosahatchee Marl to the Pleistocene, primarily on the basis of
vertebrate fossils, and to a lesser extent on mollusks and strati-
graphic relationship.
CALOOSAHATCHEE MARL
The shell beds exposed along the upper reaches of the
Caloosahatchee River were classified by Heilprin (1887) as Pliocene
in age. Matson and Clapp (1909, p. 123) adopted the name
Caloosahatchee Marl for these beds and their definition has been
in general use since that time. The formation as used in this report
comprises the sediments that contain a molluscan fauna considered
as diagnostic of the Caloosahatchee Marl.
The distribution and areal extent of the Caloosahatchee Marl
are not well known. It is exposed along the Caloosahatchee River
and has been penetrated in wells near the river and along the
margin of Lake Okeechobee (fig. 8). Shelly material dredged from
drainage canals a few miles southeast of Lake Okeechobee closely
resembles the material along the Caloosahatchee River. DuBar
(1958, p. 85, fig. 29) indicates that the Caloosahatchee Marl ranges
in thickness from 5 to 25 feet in areas adjacent to the river and
downstream from LaBelle. Upstream from LaBelle test wells
penetrated 45 to 65 feet of the formation, but did not reach the
bottom. Generally, the Caloosahatchee Marl ranges in thickness
from 15 to 30 feet, although thicknesses of 60 feet have been noted.
The formation appears to be a discontinuous deposit, occurring as
erosional remnants filling depressions in the older eroded surface
of the Tamiami Formation.
The Caloosahatchee Marl consists predominantly of unconsoli-
dated sand and sandy marl that contain abundant marine mollusks.
In addition to the profusion of mollusks, one of the outstanding
features of the formation along the banks of the Caloosahatchee
River is a 2-foot layer of hard, solution-riddled marine limestone
FLORIDA GEOLOGICAL SURVEY
which Dubar (1958, p. 58) calls the Bee Branch Member. About
21' miles upstream from LaBelle the Bee Branch Member of DuBar
dips beneath the waterline. Schroeder and Klein (1954, p. 5)
indicate that in eastern Hendry County a greenish silty sand and
sandy marl, derived from erosion of green clay marl of the Tamiami
Formation, composed a part of the Caloosahatchee Marl. These
greenish sediments appear to be restricted to the flanks of the
hills of the eroded Tamiami Formation.
In general, the Caloosahatchee Marl has low permeability and
is a relatively unimportant source of ground water. Small yields
can be obtained from shell beds and lenses, but in areas adjacent
to the Caloosahatchee River where the Bee Branch Member of
DuBar is best developed in the subsurface, the formation may
yield fairly large quantities of water by infiltration from the river.
In the area along the west shore of Lake Okeechobee the water is
usually highly mineralized.
PLEISTOCENE SERIES
Formations of Pleistocene age in southern Florida are the sands
of the marine terraces, the Anastasia and Fort Thompson
Formations, the Key Largo Limestone, and the Miami Oolite. The
higher terraces of early Pleistocene age, the Miami Oolite, and
Key Largo Limestone do not occur in Glades and Hendry counties.
The Anastasia Formation and the terrace sands are of marine
origin and the Fort Thompson Formation is a succession of marine
and fresh-water beds.
The different elevations of the Pleistocene shorelines and the
alternation of marine and fresh-water beds in the Fort Thompson
Formation give a record of the oscillation of sea level during the
ice age. Although the maximum advances of ice sheets were far
to the north, their advances and retreats affected Florida by
alternately lowering and raising the level of the sea as water was
being frozen or melted and consequently was being withdrawn from
or added to the ocean.
The Pleistocene deposits in Glades and Hendry counties are
chiefly quartz sands, shell beds, limestone, and marl.
ANASTASIA FORMATION
The Anastasia Formation was named by Sellards (1912) for
outcrops of coquina on Anastasia Island, near St. Augustine,
Florida. Cooke and Mossom (1929, p. 199) expanded this definition
to include all the marine deposits of Pleistocene age underlying the
REPORT OF INVESTIGATIONS No. 37
lowest plain bordering the east coast of Florida, excluding the
Key Largo Limestone and Miami Oolite in southeastern Florida.
Parker and Cooke (1944, p. 66) defined the formation as follows:
"The Anastasia formation as here defined includes the coquina,
sand, sandy limestone, and shelly marl of pre-Pamlico Pleistocene
age that lies along both the Florida east and west coast."
The exact distribution of the Anastasia Formation is not known.
It probably is present beneath all of Glades and Hendry counties
excluding the Everglades area in eastern Hendry County, a 5-mile
strip on either side of the Caloosahatchee River, and a strip 5 to
10 miles wide along the west shore of Lake Okeechobee. The
thickness of the formation is commonly about 2 to 3 feet and
probably does not exceed 15 feet.
The coquina limestone found at the type locality of the
Anastasia Formation does not occur in Glades and Hendry counties.
Sand, shell, and marl form most of the formation in Glades and
Hendry counties. A thin marine sandstone is the most prominent
bed in the formation. The beds in eastern Hendry County that
have been assigned tentatively to the Fort Thompson Formation
by Schroeder and Klein (1954, p. 5) are apparently transitional
between the Fort Thompson and Anastasia Formations. The
formation is overlain unconformably by the Pamlico Sand and
underlain unconformably by the Caloosahatchee Marl.
A few wells for domestic supplies and numerous wells for
watering stock derive water from the Anastasia Formation. The
water is generally colored and high in iron content.
FORT THOMPSON FORMATION
The alternating fresh-water and marine limestones exposed
along the Caloosahatchee River at Fort Thompson, about 2 miles
east of LaBelle, were initially named the Fort Thompson beds by
Sellards (1919, p. 71-72). Cooke and Mossom (1929, p. 211-215)
later named this sequence the Fort Thompson Formation and
indicated that the beds lie unconformably on the Caloosahatchee
Marl and are overlain by the Lake Flirt Marl of Recent age.
The Fort Thompson Formation in Glades and Hendry counties
has its maximum thickness in the southern part of the Everglades
basin. It extends in a strip about 5 miles wide near the eastern
border of Hendry County, in a strip about 5 miles on either side of
the Caloosahatchee River upstream from LaBelle, and in a strip 5
to 10 miles wide along the west shore of Lake Okeechobee. The
formation ranges in thickness from 2 to 15 feet.
The typical development at old Fort Thompson shows alter-
FLORIDA GEOLOGICAL SURVEY
nating beds of marine shells and fresh-water limestones. The
limestones apparently are case-hardened marl.
The Fort Thompson Formation lies unconformably upon the
Caloosahatchee Marl and is overlain unconformably by the Pamlico
Sand or Recent soil and marl. Parker and Cooke (1944, p. 89-96)
correlated the beds at old Fort Thompson with the inferred
fluctuations of sea level during the Pleistocene Epoch. They
considered the Pamlico Sand to be of mid-Wisconsin age, but later,
Cooke (1952, p. 51) referred it to the Sangamon Interglaciation.
The beds along the river downstream from the Ortona Lock,
in the vicinity of station 343 of Parker and Cooke (1944, p. 93),
have been studied in detail by the authors. At that locality the
Fort Thompson Formation is 6 to 7 feet thick and is described
as follows:
Thickness
Description (feet)
Fort Thompson Formation:
10. Shell beds, marine (Coffee Mill Hammock Marl Member) -- 1 -2
Diastem
9. Marl, sandy, containing marine shells in lower part-------- 0 -2
Diastem
8. Marl, fresh-water -----..--.-.-----------------------...................... ... .
7. Shell marl, marine, silty .... ..----.--. -- --.......-.................. -1
Diastem
6. Limestone, fresh-water ...--- .... ------...... ....... --........-----....---. .. 0 -
5. Shell marl, marine, silty ---- --....------................................. 1 -2
Diastem
4. Limestone, fresh-water .... ...-------------...---........... .... 0 %
3. Shell marl, marine, Vermnicularia bed .---------... --.--------........... 1 -2
Diastem
2. Limestone, sandy, fresh-water ....-----------.. ..............-....-. -1%
Diastem
Caloosahatchee Marl:
1. Shell marl, marine
Parker and Cooke included beds 2 and 3 of the section in the
Caloosahatchee Marl. However, fresh-water gastropods were
abundant in bed 2 for 1,700 and 800 feet, respectively, on the left
and right banks of the river. Therefore, the top of the Caloosa-
hatchee Marl is placed tentatively below bed 2. Typical
Caloosahatchee shells were not found in bed 3. In this area, as
noted, the four fresh-water beds (beds 2, 4, 6, and 8) may indicate
glaciations, and the six diastems suggest short periods of lowered
sea levels and breaks in sedimentation.
The deposition of the Anastasia and Fort Thompson Formations
and the terrace deposits was the result of the oscillation of sea
REPORT OF INVESTIGATIONS NO. 37
level during the Pleistocene. During the interglacial stages the
high-level seas covered the area, and during the glacial stages,
when the sea levels were below present levels, most of the area
was being eroded but fresh-water marls were being deposited in
shallow depressions. The Lake Okeechobee-Everglades Basin and
a subsidiary basin in the Caloosahatchee River valley probably
were lakes or swamps during a part of each glacial period. It
appears that a drainageway from the Lake Okeechobee area toward
the Gulf of Mexico existed during the glacial periods and conditions
were somewhat similar to those prior to the dredging of the
Caloosahatchee River.
The Fort Thompson Formation generally does not yield large
quantities of water in Glades and Hendry counties because the
limestones are usually of low permeability and the shell beds
contain silt and clay. Small supplies can be obtained from shell
beds by jetting and removing the fine materials from the zone
surrounding the bottom of well casings.
TERRACE DEPOSITS
The terrace deposits in Glades and Hendry counties are
composed of quartz sand referred by Parker and Cooke (1944, p.
74-77) to the Pamlico, Talbot, and Penholoway terraces. The old
shorelines of these deposits occur at about 25 feet, 42 feet, and 70
feet above sea level, respectively, and are associated with glacial
control of sea level during the Pleistocene Epoch.
Terrace sands mantle all of Glades and Hendry counties, except
the areas covered by Recent organic soils and marls in the Ever-
glades, and the Lake Flirt basin along the Caloosahatchee River.
Usually the sands are 2 to 3 feet thick, but where they overlie old
depressions they may be as much as 15 feet thick. The terrace
sands lie unconformably upon the Fort Thompson or Anastasia
Formations of Pleistocene age, the Caloosahatchee Marl of Pliocene
age, and the Tamiami Formation of late Miocene age, and are
overlain unconformably by the Lake Flirt Marl and deposits of
Recent age.
Wells developed in the terrace sands are generally driven
sandpoints. Well 237 in northwestern Glades County is a dug well
and holds its form because it penetrates iron-cemented "hardpan."
The water from this well is undesirable for domestic use because
it is high in color and has a high iron content.
FLORIDA GEOLOGICAL SURVEY
RECENT SERIES
The deposits of Recent age in Glades and Hendry counties
include the organic soils of the Everglades and the Lake Flirt
Marl. The marl and the parent material for most of the organic
soils accumulated in a fresh-water environment.
LAKE FLIRT MARL
The Lake Flirt Marl was the name applied by Sellards (1919,
p. 73-74) to the fresh-water deposits overlying the Fort Thompson
Formation and the Pamlico Sand in the now-drained Lake Flirt
area east of LaBelle. The approximate extent of these fresh-water
deposits is shown in figure 2.
The maximum thickness of the formation along the banks of
the Caloosahatchee River is 6 to 8 feet. In addition to gray and
brown marl containing fresh-water gastropods, the formation is
composed of dark sticky muck, sandy marl, and carbonaceous sand.
The low permeability of the Lake Flirt Marl precludes its develop-
ment as an aquifer.
ORGANIC SOILS
After the close of the Pleistocene Epoch, organic soils began
to accumulate in the Lake Okeechobee-Everglades Basin and in
shallow ponds, lakes and swamps. The maximum thickness of the
organic soils is about 8 feet in eastern Hendry County. They are
composed of brown to black peat and muck. Along the western
edge of the Everglades, quartz sand from the terrace deposits was
reworked and mixed with the organic material.
Several samples of peat, collected from the lowermost 6 inches
of organic soil that immediately overlie the rock floor of the
Everglades, have been dated by radioactive carbon determinations.
The age of the peat was determined as follows: mucky peat at the
Everglades Experiment Station near Belle Glade in Palm Beach
County, 4900 years 200 years; fibrous peat near the same loca-
tion, 3,800 years 200 years; and peat from the vicinity of U. S.
Highway 27, 10 miles south of Lake Okeechobee in Palm Beach
County, 5,050 years 200 years.
Peat is considered to be resistant to the lateral seepage of water.
This characteristic and the low permeability of the materials
underlying the organic soils make flood control and water control
feasible in the Everglades area of Glades and Hendry counties
REPORT OF INVESTIGATIONS No. 37
through the use of canals, pumps, and levees. The high organic
content of the soils makes the ground water contained in the soils
undesirable for domestic use.
GROUND WATER
OCCURRENCE AND MOVEMENT
The basic principles that govern the occurrence and movement
of ground water have been thoroughly described by Meinzer (1923).
Following is a summary of these principles as they relate to Glades
and Hendry counties and most areas of southern Florida.
The chief source of ground-water recharge in Glades and Hendry
counties is rainfall. Part of the rainfall evaporates, a part is
absorbed by plants and transpired into the atmosphere, and a part
is lost by surface runoff. The remainder infiltrates downward
through the surface materials until it reaches the zone of satura-
tion to become part of the body of ground water. The upper
surface of the saturated zone where not confined by an impermeable
bed is the water table.
Ground water is stored in the openings, solution cavities, and
pore spaces within the consolidated and unconsolidated materials of
the earth's crust. The amount of water that can be stored in
water-bearing materials is determined by the porosity of the
materials. Porosity is controlled by such factors as the shape,
arrangement and assortment of the components, the amount of
cementing material in the interstices, and the degree of compaction
of the sediments.
The permeability of a water-bearing stratum is its ability to
transmit water under a hydraulic gradient. Clay, marl, and fine
sand, although highly porous, are of low permeability, but coarse
sand, gravel, and cavernous limestone are highly permeable because
the interstices are large and interconnected. A formation, group of
formations, or part of a formation that transmits appreciable
quantities of water to wells and springs is called an aquifer.
The water table is an undulating surface that conforms in a
general way to the topography of the land. It fluctuates seasonally
in southern Florida, rising during rainy seasons and declining
during dry periods, and responds to such forces as evaporation,
transpiration, and pumping from wells. Ground water moves down-
gradient from areas of recharge to areas of discharge.
The gradient of the water table depends upon the thickness and
FLORIDA GEOLOGICAL SURVEY
permeability of the aquifer and the quantity of water moving
through the aquifer. A steeper gradient is required to move a
given amount of water through an aquifer of low permeability than
through an aquifer of high permeability.
An aquifer where the upper surface of the zone of saturation
is not confined by impermeable material contains water under
nonartesian (or water-table) conditions. The water level in a well
penetrating the saturated zone of an unconfined aquifer is a
measure of the altitude of the water table.
Where ground water has moved laterally into permeable
material that is overlain by an impermeable layer and it is under
sufficient pressure to rise above the top of the material containing
it, it is said to occur under artesian (confined) conditions. The
water level in a well penetrating an artesian aquifer will rise
above the top of the aquifer to a point that is the approximate
measurement of the pressure head. The pressure head is due to the
weight of the water in upgradient areas of the aquifer.
Glades and Hendry counties are underlain by an artesian
system that extends beneath Florida and southeastern Georgia.
The system will yield flowing water to deep wells in all Hendry
County and all but northwestern Glades County. Glades and
Hendry counties are underlain at shallow depth by less extensive
aquifers which exhibit both nonartesian and artesian character-
istics. Water levels in wells penetrating these aquifers respond
to local recharge by rainfall and to evapotranspiration, but also are
affected by changes in barometric pressure and by earthquakes.
Figures 9-12 show the locations of deep and shallow wells
inventoried in Glades and Hendry counties.
FLORIDAN AQUIFER
The principal artesian aquifer beneath Florida was described
by Stringfield (1936) and was named the Floridan aquifer by
Parker (1951, p. 819). The part of the Floridan aquifer penetrated
by deep artesian wells in Glades and Hendry counties consists of
water-bearing limestones that range in age from middle Miocene to
Eocene. The depth of the base of the Floridan aquifer is not
known, but rocks older than Eocene probably contain highly
mineralized water in most of Glades and Hendry counties. The
aquifer is overlain by clay, sandy clay, and marl of the Hawthorn
Formation, which form a relatively impermeable confining layer.
The clay and marl in the lower part of the Hawthorn Formation
are interbedded with water-bearing limestones. These limestones.
... A-- 34E 0.
-- 6 S5.5JNT e
S OLADES COUNTY \ o
c r OKEF H2O. pE
1 Ua. In ,
IN, \41 : JUU
EXPLANATION Pi4! 1i3 I5
sIONFLOWI, WELL O 3r A E" c -r
S....... .....1 1 G C T .
A NUMB ER r \ -. -
.1., VA '.,. 'a9 v
A M
\r"\r 3
HIGHLANDS COUNTY 95. I4
GLADES COUNTY
*13 z
S 76 i6Is 4
o IIW 0
4,1 ou '*'. ''U
P 70. ,L A AU. :
.,......-...-.-.-...-' COQ I.
M.4hOR* COUNTY
Figure 9. Glades County showing the locations of wells
~~~~A' ~ ~ ~ 2 *:. 1 5 C1 MO GNA'U 4
34 FLORIDA GEOLOGICAL SURVEY
~ Z [NON couNF l1"= C .
"" -i i Mi" -^ ^ ,
I I
Figure 10. Hendry County showing the locations of wells.
which usually occur at depths ranging from 300 to 400 feet, are
not as productive as the deeper limestones; therefore, most of the
artesian wells in Glades and Hendry counties are bottomed in the
highly permeable Tampa Formation or the Suwannee Limestone.
The limestones of the Floridan aquifer in Glades and Hendry
counties are not homogenous, and in many cases, most of the yield
of a given well may be contributed by two or three thin, highly
permeable zones. One of the highly productive parts of the aquifer
is at the top of the Tampa Formation. The limestones in the lower
part of the Hawthorn Formation are included as part of the aquifer
unit; however, the artesian pressure in these layers is much lower
than it is in the Tampa Formation, which suggests that they ma3
constitute a separate aquifer.
In table 4 (Bishop, 1956, p. 113) the artesian pressure an6
the yield of well 22, Glades County, increased sharply between
depths of 573 feet and 610 feet, below the land surface as the.
well passed from the Hawthorn Formation into the Tampi
...I ,,'L :
artesian wells in Glades and Hendry counties are bottomed in the
counties are not homogenous, and in many cases, most of the yield
of a given well may be contributed by two orthe th thin, highly
permeable zones. One of the highly productive parts of the aquifer
is at the top of the Tampa Formation. The limestone in the lower
part of the Hawthorn Formation are included as part of the aquifer
unit; however, the artesian pressure in these layers is much lower
than it is in the Tampa Formation, which suggests that they rna;
constitute a separate aquifer.
In table 4 (Bishop, 1956, p. 113) the artesian pressure and
the yield of well 22, Glades County, increased sharply between
depths of 573 feet and 610 feet, below the land surface as the
well passed from the Hawthorn Formation into the TampdL
REPORT OF INVESTIGATIONS No. 37
I __11_ 174 ____
Figure 11. LaBelle and vicinity showing the locations of wells.
Formation. After the first major flow (200 gpm) was obtained at
610 feet, the yield from the remainder of the hole (610 to 1,215
feet) increased at an irregular rate to 585 gpm. The data indicate
that the interval between 610 and 616 feet in the upper part of
the Tampa Formation is the zone of the highest permeability at
this site.
FLORIDA GEOLOGICAL SURVEY
EXPLANATION LINE
*229
Nonfl oing well 1 '196
ind number I
SCA:_E IN MILES '230
Figure 12. Clewiston and vicinity showing the locations of wells.
Several flowing wells are used to irrigate pastures and farmland
north of the Caloosahatchee River, about 6 miles northeast of
LaBelle. Fairly good geologic and hydrologic data and accurate
well construction information are available on wells 201, 238, and
239 in this area of Glades County.
Wells 201 and 238 were cased to a depth of 203 feet, but the
original drilled depths of the wells differed by 142 feet (well 201,
642 feet; well 238, 500 feet). When the wells were completed, well
201 yielded 385 gpm and well 238 yielded 730 gpm. Well 239, 1
mile to the northeast, was cased to a depth of 254 feet, and was
completed at a depth of 716 feet; its initial yield was 310 gpm. The
TABLE 4.1 Water-level and Flow Measurements Made During Drilling of Well
22, Glades County
I Casing seated at 432 feet]
Depth of
well below Water level Average increase
land surface above land Yield by in yield per foot Geologic
Date ( feet) surface (feet) flow (gpm) of interval (gpm) formation
1951
Feb. 24 500 __ Trace Hawthorn
Feb. 27 515 6.0 Do.
Feb. 23 573 6.0 Do.
Mar. 1 610 30.0 200 Tampa
Mar. 1 616 290 15.0 Do.
Mar. 1 632 32.0 Ocala
Mar. 1 667 310 0.4 Do.
Mar. 1 677 340 3.0 Do.
Mar. 1 670 31.0 Do.
Mar. 2 854 395 0.3 Do.
Mar. 5 1.119 420 .1 Avon Park
Mar. 5 1,134 445 1.7 Do.
Mar. 5 1,164 480 1.2 Lake City
Mar. 6 1,190 30.0 565 3.3 Do.
Mar. 6 1.215 31.0 585 .8 Do.
iTable condensed from Bishop, 1956 (p. 113).
REPORT OF INVESTIGATIONS NO. 37
relatively large differences in the amount of casing in the wells,
the amount of aquifer penetration needed to obtain substantial
yields, and the differences in the individual well yields indicate
that the confining beds of the Hawthorn Formation in this general
area are of nonuniform thickness and lithology, and that the
water-yielding properties of the limestones composing the aquifer
differ both laterally and vertically.
Two months after these wells were drilled additional measure-
ments of -depth and flow were made, and traverses with a deep
well current meter were made in wells 201 and 238 to measure the
velocity of flow through the well bores at different depths. The
measurements showed that the depth and yield of well 238 were
the same as originally determined, but that the open-hole part of
well 201 had filled in 38 feet and the yield had been reduced by
35 gpm. Data obtained from the current-meter traverses in these
wells are shown in figure 13. The graphs show the relative velocity
of the ground water moving upward at different depths in the
wells and presents the percentage of the total flow that enters
the well bores from different intervals. About 40 percent of the
total yield of well 201 was contributed by the limestone section
between 510-520 feet; nearly 40 percent of the total flow of well
238 was contributed by the 5-foot section at the bottom of the
well. Flow measurements made in these wells in May 1958 showed
that the yield of well 238 had declined from 730 to 650 gpm, and
that of well 239 had declined from 310 to 230 gpm.
Similar studies were made on two 8-inch flowing wells in
Hendry County (wells 278 and 279), about 9 miles southwest of
LaBelle. The yield of well 279 diminished from 500 gpm in
August 1953 to 200 gpm in March 1954. The graph of the results
of the current-meter traverse of well 279 (fig. 13) shows that 40
percent of the yield was contributed from the interval between
440 and 460 feet. Flow data obtained in May 1958 indicate that
the yield of well 279 had not changed from the 200 gpm rate of
March 1954.
Well 278, a quarter of a mile south of well 279, yielded 760
gpm when it was completed in July 1953, but by March 1954 the
discharge had diminished to 400 gpm, and by May 1958 it was
320 gpm. The well has 8-inch casing from the land surface to a
depth of 290 feet and 6-inch casing between 378 and 520 feet,
leaving an open hole between 290 and 378 feet and between 520
feet and the bottom of the well, at 790 feet. Some yield was
obtained from the zone between 290 and 378 feet, but the source
of most of the water apparently was the zone below the bottom
FLORIDA GEOLOGICAL SURVEY
I DEPTHIN FEET BELOW LAND SURFACE I
Figure 13. Graphs showing the distribution of flow in selected wells in Glades
and Hendry counties.
of the lower casing. Water samples collected at 340 and 377 feet
(upper open-hole part) contained 1,000 ppm of chloride, practically
the same concentration as in samples obtained from the lower
open-hole section and also from the discharge outlet. However, a
water sample taken at a depth of 400 feet in well 279, to the north,
contained 665 ppm of chloride. This suggests that the 400-foot
zone, which had been cased off in well 278, contains relatively
fresh water, and that the major part of the yield is from the deeper
saline zones.
If the open-hole part of a flowing well is of uniform diameter
and the aquifer has uniform pressure, the water velocity should
increase from the bottom of the hole upward. The flow distribution
in well 279 (fig. 13) indicates that the size of the hole is not
uniform. Where the hole is enlarged opposite sections of the
aquifer consisting of soft material, the velocity of the water
decreases because of the larger cross-sectional area. Possibly some
decrease in flow may result from loss of water into sections of the
GLADES COUNTY
WELL 201
DEPTH 604 Fl
CASED 203 Fl
FLOW 350 GPM
REPORT OF INVESTIGATIONS NO. 37
borehole where the pressure is lower than the pressure in the
main yielding zones.
PIEZOMETRIC SURFACE
The piezometric surface is an imaginary surface representing
the pressure head of water confined in an artesian aquifer. It is
defined by the height to which water will rise in tightly cased wells
that penetrate the aquifer. Where the piezometric surface is
higher than the land surface, wells tapping the artesian aquifer
will flow.
In peninsular Florida the piezometric surface is highest in
central Polk County where the aquifer is recharged, and lowest
in coastal areas where discharge takes place. Over much of south
central Florida the piezometric surface is relatively flat and has a
general southeasterly slope.
The configuration of the piezometric surface in Glades and
Hendry counties is shown in figure 14, by contours which indicate
that artesian water in the Floridan aquifer is flowing generally
southeastward from the Highlands Ridge area into Glades County.
A mound in the piezometric surface in eastern Hendry County and
southwestern Palm Beach County (fig. 14) indicates that ground
water is flowing outward in all directions from that generally high
area. This suggests that the Floridan aquifer is being recharged
in that area; however, the height of the piezometric surface there
is 30 feet or more above the land surface, and thus there is no
possibility of local downward recharge. This piezometric high
probably is a residual mound that has resulted from the discharge
of flowing wells in the areas to the northwest.
RECHARGE
At some places in north, central, and northwestern Florida the
Floridan aquifer is exposed at the surface, but throughout the
remainder of Florida the aquifer dips beneath the surface and is
covered by layers of sand and clay of low permeability which form
a confining unit. At the outcrop area the aquifer is recharged
directly by rainfall. Recharge to the Floridan aquifer occurs also
in the high areas of central Florida where the water table is
perennially higher than the piezometric surface of the aquifer;
replenishment occurs by downward infiltration through semi-
permeable layers of the Hawthorn Formation. According to
Stringfield (1936, p. 148) the artesian aquifer in parts of central
FLORIDA GEOLOGICAL SURVEY
i OKEECHOBEE
4- OORE HAVEN
/ .56
M 6 E END COUNTY
A ELLE .- L
.52 CLEWISTON
0 / \
53 7
I .9 / IC
56
54 5 61
s COuLIER feet above0
55mean sea level in 1958;
Well and water leveling feet
Line showing approximate (fig.
altitude ofthe piezometric
surf ace, in feet above
mean sea level in 1958;
dashed where inferred ._X _. HE\aY_ COUN_ _____CJ"
*59 \ '--' -''OLL5 R COUNTY
Well and water level,in feet
A-----A'
Line of water-level profile(fig.15)
SCALE IN MILES
2 0 2 4 6 8 10 54
Figure 14. Glades and Hendry counties showing the configuration of the
piezometric surface of the Floridan aquifer, 1958.
REPORT OF INVESTIGATIONS NO. 37
Florida is blanketed by permeable material, thus permitting ready
recharge to the aquifer.
It is probable that replenishment to the Floridan aquifer by
downward infiltration occurs in much of the Highlands Ridge area
of central Florida. Water-level measurements by Bishop (1956, p.
46-48), during the drilling of a deep well in southern Highlands
County, substantiate the theory that recharge to the Floridan
aquifer occurs as far south as the town of Venus in southern
Highlands County. The water in the Floridan aquifer beneath
Glades and Hendry counties moves southward beneath the con-
fining layers of the Hawthorn Formation in a general direction
normal to the piezometric contours shown in figure 14.
DISCHARGE
Most of the discharge from the Floridan aquifer in Glades
and Hendry counties probably occurs through artesian wells used
to irrigate winter vegetable crops and pastureland. The total water
discharged during the seasons of heavy irrigation is about 10 mgd
(million gallons per day). Hendry (1957, p. 19) estimated that
about 50 wild, flowing wells in the two counties discharge water
at a total rate of approximately 3 mgd. Many of these wells are
west and southwest of LaBelle.
The layers and lenses of clay, sandy clay, and fine sand of low
permeability that compose the middle and upper parts of the
Hawthorn Formation in the two counties tend to prevent upward
leakage from the Floridan aquifer. However, where sand is the
chief component of the confining unit or where the Hawthorn
Formation is thin (figs. 6, 7), upward leakage may occur because
of the high pressure differential (30-40 feet) between the
piezometric surface and the water table.
WATER-LEVEL FLUCTUATIONS
The water levels in an artesian aquifer fluctuate in response to
recharge by rainfall, discharge, earthquakes, and variations of
barometric pressure. Fluctuations due to rainfall are most apparent
in the vicinity of the recharge area. However, water levels in
deep wells in Glades and Hendry counties are only slightly
affected by seasonal rainfall because the wells are a great distance
'rom the recharge area. Large fluctuations of the piezometric
surface are due to discharge from wells during periods of irrigation.
FLORIDA GEOLOGICAL SURVEY
Figures 9, 10, and 11 show the locations of inventoried flowing
wells in Glades and Hendry counties, though they do not show all
the flowing wells in the area. The concentration of wells is greatest
along the Caloosahatchee River from Ortona westward to the Lee
County boundary. The cones of depression in the piezometric
surface (fig. 14) are evidence of the heavy discharge from the
Floridan aquifer in this area where many wells have been in use
for 50 years or more. It is estimated that 50 percent of them are
no longer maintained and are leaking through corroded casings or
are flowing wild. Such heavy discharge over a long period of time
is responsible for the overall decline in pressure in that area, and
this may have caused the quality of the water to deteriorate.
Probably the quality of the water derived from the Floridan aquifer
in the vicinity of LaBelle during the early days of the development
was superior to the quality in 1958.
A second area of heavy water use is in northeastern Glades
County and the adjoining part of Okeechobee County, where crops
and pastures are frequently irrigated. The lowering of the
piezometric surface caused by this discharge is shown in figure
14. The lowered pressure in this area and the lowered pressure
caused by discharging wells north of Lakeport and in the vicinity
of Palmdale have produced the northeastward-trending trough in
the piezometric surface in Glades County.
Few, if any, artesian wells have been drilled to the Floridan
aquifer in the Everglades south of Lake Okeechobee, and the
piezometric surface in this area has remained at its approximate
original level. Artesian water is moving downgradient from this
area of high pressure and as the mound is not being recharged, a
slow decline of pressure can be expected until a new gradient from
the recharge area is established. It may be many years before
this gradient adjustment is completed.
Figure 15 is a series of water-level profiles of the Floridan
aquifer in Glades and Hendry counties. These profiles show the
effect that the discharging wells have on the piezometric surface.
Profile A-A' shows that recharging water moves downgradient
from the high areas in Highlands County toward the cone of
depression in the vicinity of LaBelle. Profile B-B' crosses from the
high water level in Highlands County southeastward through the
saddle-shaped depression in the vicinity of Palmdale to the residual
high-pressure area in eastern Hendry County. Profile C-C'
shows a relatively steep gradient from Highlands County southeast-
ward to the area of heavy withdrawals near lake Okeechobee.
REPORT OF INVESTIGATIONS NO. 37
I B B'
S HIGHLANDS z GLADES HENRY
COUNTY COUNTY COUNTY
M<6 I W I . .
=50
_j
G> C HIGHLANDS GLADES coW
60 COUNTY I COUNTY
--J
Ar NML
t- 0 P See figure 14 for location of profiles
Figure 15. Profiles of the piezometric surface of the Floridan aquifer in
Glades and Hendry counties, 1958.
SHALLOW AQUIFERS
The shallow aquifers in Glades and Hendry counties range in
age from middle Miocene to Pleistocene. Permeable beds of shell,
limestone, or mixtures of sand and gravel in the Tamiami
Formation and the upper part of the Hawthorn Formation are the
principal sources of ground water for shallow wells. Wells tapping
these aquifers range in depth from about 10 feet to more than 300
feet. The shallower wells generally penetrate shell beds or lime-
stone in the Tamiami Formation. They are finished with a few feet
of open hole and yield relatively small amounts of water in Glades
County and most of northern and western Hendry County. In
1953 few irrigation wells produced water from the shallow aquifers
in Glades County because the Floridan aquifer, in most areas
yielded usable water in large quantities without the use of pumps.
In Hendry County the Floridan aquifer yields water that is
generally unsuitable for irrigation, and farmers must depend on
the shallow aquifers for fresh-water supplies. Truck-crop farmers
FLORIDA GEOLOGICAL SURVEY
in the Devil's Garden, the Big Cypress Swamp, and the Everglades
areas irrigate with wells that range in depth from about 50 feet
to more than 300 feet. The deepest of these is well 194, 6 miles
northeast of Felda (fig. 10); it was drilled to a depth of 326 feet,
and was reported to tap one of the gravel beds within the Hawthorn
Formation.
The principal shallow aquifer in the area is in the southern
and central parts of Hendry County, and is composed of highly
permeable limestone of the Tamiami Formation. Geologic
information obtained from well 131 in Collier County, due east of
Immokalee at the Hendry County boundary, shows the top of the
aquifer to be at a depth of 22 feet, and that permeable limestone
extends to a depth of at least 54 feet. In this area the aquifer is
overlain by 5 feet of surficial, medium-grained sand and 17 feet of
sandy, shelly clay of low permeability. The clay retards the down-
ward infiltration of water to the aquifer.
Further information indicates that the aquifer thins out 3 to
5 miles west of well 131 in Collier County. The increase in the
depth of wells eastward from well 131 suggests that the highly
permeable limestone in the aquifer dips to the east. The depth to
the top of the limestone in the Devil's Garden area (fig. 2) is about
120 feet. Eight miles north of well 131 the aquifer probably is
thinner, as indicated by the shallow depth of irrigation wells in
that area. The greatest extent of the aquifer is southward, where
it probably underlies all of southern Hendry County and most of
Collier County. Similar permeable limestone was noted in rockpits
as far south as southern Collier County.
Data from well 4, 9 miles west of Clewiston, in Hendry County,
indicate that the top of a shallow aquifer in that area occurs at
96 feet below the land surface. This aquifer extends to 127 feet
and is reported to be composed of fine to coarse gray sand mixed
with well rounded pebbles. The aquifer may be the basal part of
the Tamiami Formation or possibly one of the pebble beds of the
Hawthorn Formation. The well is finished with 5 feet of slotted
casing, is gravel packed, and is reported to yield 180 gpm. The
overlying material is composed of sandy, shelly marl of low
permeability.
Wells penetrating the shallow permeable layers in LaBelle and
vicinity range in depth from about 60 to 175 feet, but most are
between 20 and 100 feet deep. A study of rock cuttings taken
during the drilling of well 277, in the southern part of Labelle,
shows that layers of clay, shelly marl, and fine sand are interbedded
with layers of limestone to a depth of 170 feet. The clay and
REPORT OF INVESTIGATIONS NO. 37
shelly marl are of low permeability and tend to retard ground-water
movement between the thin sections of higher permeability. The
sediments in general are poorly sorted and grade laterally as well
as vertically into material of different composition.
The shallow sediments in Glades County generally have low to
moderate permeability, and most large capacity wells penetrate the
Floridan aquifer even though the quality of the water is usually
poorer. The shallow aquifers in Glades County are composed of
sand and pebble beds or discontinuous limestone beds of the Haw-
thorn Formation. The yield from shallow aquifers in Glades County
generally is lower than that from shallow aquifers in Hendry
County.
WATER-LEVEL FLUCTUATIONS
Water levels in wells that tap shallow aquifers in Glades and
Hendry counties normally are within a few feet of the land surface.
However, during rainy seasons the water levels in wells in many
areas rise above the land surface. Well 128, 3 miles west of LaBelle
and south of the Caloosahatchee River in Hendry County, flows
throughout most of the year. The well was reported to penetrate
a permeable shell bed at a depth of 76 feet.
Records of fluctuations of water levels in shallow observation
wells in and adjacent to Hendry County have been obtained since
1950. Automatic gages provide a continuous record of the daily
changes and the seasonal trends of the water levels. Hydrographs
of wells 3 and 5, in Hendry County south of Clewiston, and well 131,
in Collier County east of Immokalee, are shown in figure 16. They
reveal ground-water levels are usually at low stage during winter
and spring and are high during and immediately after the rainy
season in summer and early fall. The maximum range of fluctuation
is about 5 feet.
The greatest rise in water level accompanies the first heavy
rainfall of the wet season. The surface materials become saturated
nearly to the land surface and subsequent rainfall causes inter-
mittent flooding. The hydrograph for well 3, 30 miles south of
Clewiston, shows that the flooding had occurred in that area many
times during each rainy season and that the area was flooded
nearly the entire year of 1958.
Evapotranspiration is another cause of water-level fluctuations
in shallow observation wells. The decline of water levels caused
by evapotranspiration ranges from 0.05 to 0.15 foot per day. When
overland runoff stops after the rainy season, the persistent decline
N Wi
WELL 3, HENDRY COUNTY
30 miles south of Clewiston
wo +SpvyF VT1 111111[m il TF
,WELL 5 HENRY COUNTY I I I II Iij` 1
S 15 miles southwest of Clowiston 1
3-0
W
g21 WELL 131, COLLIER COUNTY N\ Il1
:1 m i iiia ii i H l I I 2ImLLIII Ii1 mileseastof I II 'oj 11. II I LI LLY* 14A I 1l It 1 1!i Jill J 11 1 JJI Kr'F41
Figure 16. Hydrographs of wells 3 and 5 in Hendry County and well 131 in
Collier County.
0
161A
isg&
i lll i
ri
REPORT OF INVESTIGATIONS No. 37
of water levels throughout the area is the result of the relatively
high rate of evapotranspiration.
A water-level recording gage was installed on well 234 in
LaBelle to determine the relation between the stage of the
Caloosahatchee River and the water table adjacent to the river
during 1953-54. This relation is shown in the hydrographs of
figure 17. The daily rainfall at LaBelle is included also. The
hydrograph shows the daily-average stage of the Caloosahatchee
River at LaBelle and is probably indicative of the fluctuations as
far upstream as the Ortona Lock, one of the regulatory structures
which control the water level of Lake Okeechobee. Fluctuations of
river stage at LaBelle are caused by boat-lock operation, by
variations of discharge from Lake Okeechobee through the locks
at Ortona, and by gulf tides.
The large fluctuations in figure 17 are caused by changes in the
rate of discharge through the structure at Ortona. During the
period from early February to late May 1953 the locks were open
and the average river stage at LaBelle was between 3.0 and 3.5
feet above msl. On May 22, 1953, the locks were closed and the
river stage at LaBelle declined to 0.5 foot above msl. Figure 17
shows that the 2.5-foot drop in stage had no influence on the water
level in well 234, less than 1,000 feet from the river. Similarly
the large changes in river stage that occurred during September
and October 1954 produced no corresponding changes in water level
in well 234.
Lithologic information obtained from well 234 and from out-
crops along the riverbanks at LaBelle shows that sandy and shelly
material of moderate permeability extends from the land surface
to about 6 feet above sea level. These are underlain by about 6
feet of sandy marl of low permeability. A relatively impermeable
layer of silty clay of the Tamiami Formation forms the base of the
riverbank at an elevation of about 1 foot above sea level.
Apparently, the sediments of predominantly low permeability tend
to minimize the effect on ground-water levels produced by rapid
stage changes in the Caloosahatchee River, so that the effect
extends less than 1,000 feet from the river.
RECHARGE AND DISCHARGE
The water that replenishes the shallow aquifers in Glades and
Hendry counties is derived from local rainfall. The terrain is
essentially flat and covered by moderately permeable sand, which
permits rapid infiltration to the water table. As the water table
o 9 I 1c. a upl9 a o p 195 a
I P AI ---- --tii--- --
An -
AT LA BELLE
& A~ ABU \1 --- --- --- --- ---- --- --- -------- -- --
SAILY AVERAGE N o \. W
SI II
I OJ-^i-Ll l..LL[ td.ll J L I.,I __ I. ..I I, s I h. l ,..,, l. ,1
Ro slar
Figure 17. Hydrographs of well 234 and the Caloosahatchee River at LaBelle
compared with rainfall for the period 1953-54.
0
REPORT OF INVESTIGATIONS NO. 37
throughout the area is never more than a few feet below the land
surface, the shallow sands quickly become saturated early in the
rainy season. As a result, ponding is widespread and slow overland
flow occurs. Thin layers of fine sand, marl, or clay of low
permeability that overlie shallow, aquifers tend to impede down-
ward infiltration.
Discharge of ground water occurs by outflow to the Caloosa-
hatchee River, Fisheating Creek, numerous drainage canals, and
Lake Okeechobee; by evapotranspiration; and by pumping from
wells. Ground-water losses by outflow along the uncontrolled reach
of the Caloosahatchee River probably are small because of the
general low permeability of the shallow sediments (see discussion
of water-level fluctuations). Evapotranspiration is responsible for
the largest losses of ground water from storage, because the water
table is near the surface throughout the year. The quantity of
water discharged by wells is negligible compared to natural
discharge.
HYDRAULIC CHARACTERISTICS
The ability of an aquifer to transmit water is expressed by the
coefficient of transmissibility. The coefficient. of transmissibility
is defined as the quantity of water, in gallons per day, that will
move through a vertical section of the aquifer 1 foot wide and
extending the full height of the aquifer, under a unit hydraulic
gradient at the prevailing temperature of the water (Theis, 1938,
p. 894). The coefficient of storage is a measure of the capacity of
the aquifer to store water, and is defined as the volume of water
released from or taken into storage per unit surface of the aquifer
per unit change in the component of head normal to that surface.
The leakage coefficient (Hantush, 1956, p. 702) characterizes the
ability of semiconfining layers above or below an aquifer to transmit
water. It is the quantity of water that crosses a unit area of the
interface between the permeable section and its confining layer
with a unit hydraulic gradient between the head in the permeable
section and the section supplying the leakage.
The coefficients of transmissibility, storage, and leakage that
pertain to shallow aquifers in Glades and Hendry counties were
determined by aquifer tests at seven sites (fig. 18). During each
test, the changes in water level were measured in observation wells
located at different distances from the pumped well. Figure 19
is a semilogarithmic graph of water-level drawdowns in observation
wells versus the distance from the pumping wells at five of the
FLORIDA GEOLOGICAL SURVEY
HIGHLAN S COUNTY
GLADES COUNTY
SLAKE
OKEECHOBEE
= sT=J 10.000
S:=.00025 OD OOREHAVEN
---LADES COUNTY
a...sLA BELLE HENRY COUNTY V
--""i
CLEWISTON.
T= M.0001
* io
C c T= 115.000
S=.O0025
BT=T 120,00 0 0
S=.0012 Iz
COLLIER COUNTY I ic
I
* EXPLANATION IE
B=TEST AREA
T=COEFFICIENT OF
TRANSMISSIBILITY,GPD PER FT.
S=COEFFICIENT OF STORAGE
I
1 0 2 4 6 1 10
T=96OLO
S:.00031
0 T =505.000
FS=-00016
OG
T= 250.000
S=: .00045
i HENRY COUNTY j
Figure 18. Coefficients of transmissibility and storage determined at test sites
in Glades, Hendry, and Collier counties in shallow aquifers.
REPORT OF INVESTIGATIONS NO. 37 51
DISTANCE, IN FEET FROM PUMPING WELL
2.5
8 08 8 8 s o 8 8 oi I- t r
/2
LL .5/ A -
Figure 19. Composite of semilogarithhic distance-drawdown graphs of five
indicates the approximate drawdown that would be expected at a
given distance from a well pumped at the indicated rate. There-
fore the graph can be used to determine the optimum pumping
rates and proper spacing for wells.
The field data obtained during the aquifer tests .are shown in
figure 20. The time-drawdown graphs for each test area are
accompanied by a sketch showing the location of the wells used in
the tests. The natural fluctuations of the water-level were recorded
for periods of 24 hours both before and after each test to determine
the fluctuations caused by factors other than pumping, such as
changes in atmospheric pressure and evapotranspiration. These
TEST G 6400 pm
8 4
.....................I
Figure 20. Time-drawdown graphs of water levels in observation wells, and
sketches showing locations of wells used in aquifer tests.
TEST A
310 gpm
I.-- I.---
REPORT OF INVESTIGATIONS NO. 37
corrections were subtracted, and the corrected drawdowns shown
are the result of pumping only. The amount of correction in some
cases is very significant, as indicated by the graphs of well 285 in
test E (fig. 20).
The corrected water-level drawdowns, in feet, were plotted (on
logarithmic paper) against time, in minutes, since pumping started
and divided by the square of the distance, in feet, between the
pumping well and the observation well (t/r2). The resulting curve
for each observation well was matched to a family of leaky-aquifer
type curves developed by H. H. Cooper, Jr., of the U. S. Geological
Survey, from the equations developed by Hantush and Jacob
(1955). By superposition, match points were established for the
best fit of the corrected data to the type curves, and the
coefficients of transmissibility, storage, and leakage were calculated
from the match points. Table 5 gives the results of these computa-
tions for the seven aquifer tests. The coefficients of transmissibility
and storage shown on the map of figure 18 represent the average
values for each test.
The calculated values indicate that the aquifer composed of
limestone of the Tamiami Formation that underlies the area east
of Immokalee (test E) has the highest transmissibility. The
results of tests F and G show a decrease in the coefficient of
transmissibility to the east. This confirms information reported
by well drillers that limestone layers become thinner in the
vicinity of test G and much of the material is composed of fine and
medium sand. A marked decrease in the coefficient of trans-
missibility is shown also to the north in test sites B and C. In
these areas the aquifer is probably thin or the limestone section
grades to a marly, partly consolidated shell bed.
A basic assumption of the leaky-aquifer method of analysis is
that the water level in the material supplying the leakage does not
decline during the period of pumping. Under this condition, when
the cone of depression (which forms around the pumped well) has
expanded to the extent that the total rate of downward leakage is
equal to the rate of withdrawal no further appreciable drawdown
will take place in the aquifer as a result of pumping. This
condition is closely approximated when an area is flooded or where
an area is dissected by a network of canals in which water can be
maintained at a constant level.
On the other hand, where there is no source of water to maintain
downward leakage at a constant rate, the water table will begin
to decline after prolonged pumping. As the water table declines,
the rate of downward leakage is reduced because of the reduction
TABLE 5, Coefficients of Transmissibility, Storage, and Leakage in Glades, Hendry and Eastern Collier Counties
Well no.' Depth of well
(feet)
.. _. n. .
A 5.20.58 HE 813 HE 312 125 125 1,850 310 70,000 6.05x10-- 2.77x10--J0 8/ .81
B 7-80-58 HE 820 HE 822 84 84 165 700 100,000 1.38x10-3 4.80x10-0 28 8.67
B 7-80-58 HE 820 HE 828 84 28 2,400 700 140,000 0.20x10-4 1.44x10-o 28 .66
C 6-20-58 HE 800 HE 299 97 72 015 840 110,000 2.78x10-4 1.08x10-6 24 8.05
C 6-20-58 HE 800 HE 801 97 98 2,800 840 120,000 2.30x10-- 1.03x10-- 24 1.12
D 8-14-58 GL 260 GL 258 80 78 3,200 340 115,000 2.95x10-1- 1.65x10-7 1111 .51
D 8-14-58 GL 260 GL 250 80 82 855 340 105,000 2.06x10-,4 1.81x10-7 11 1, 1.57
E 6-17-58 HE 286 HE 285 40 40 1,380 1,800 085,000 2.98x10-- 2.33x10-7 25 .63
E 6-17-58 HE 286 HE 287 40 51 3,220 1,300 1,070,000 1.98x10-4 5.47x10-7 25 .40
E 0-17-58 HE 280 HE 288 40 40 3,580 1,800 905,000 2.73x10-4 1.08x10-o 26 .82
E 6-17-58 HE 286 HE 806 40 41 140 1,800 085,000 4.16x10-4 2.05x10-- 25 1.28
E 6-17-58 HE 286 C 181 40 54 2,750 1,800 995,000 2.76x10-4 1.10x10-0 25 .41
E 6-17-58 E 286 C 1065 40 51 5,550 1,800 880,000 8.85x10-4 1.60x10- 25 .21
F 6-18-58 HE 289 HE 290 70 80 1,800 1,570 500,000 1.63x10-4 2.80x10-7 14 1.41
F 6-18-58 HE 289 HE 291 70 92 2,800 1,570 515,000 1.49x10-4 8.60x10-7 14 1.21
G 6- 3-58 HE 808 HE 802 120 121 600 1,400 280,000 6.00x10-4 5.00x10-7 48 8.80
G 6-. 8-58 HE 808 HE 304 120 122 1,415 1,400 265,000 2.97x10-4 1.23x10-7 43 2.68
'C-Collier County, GL-Glades County, HE-Hendry County.
"Gpd per square foot per foot of vertical head; Hantush, 1956, p. 706.
REPORT OF INVESTIGATIONS NO. 37
of head differential between the water table and the piezometric
(pressure) surface of the highly permeable section of the aquifer.
The cone of depression then must expand to intercept additional
water to supply the pumping well.
After a long period of pumping and no replenishment to the
shallow aquifer, the water table will lower gradually and tend to
coincide with the piezometric surface. The entire system will then
behave as an unconfined unit.
These drawdown conditions are pictured in figure 21, which
shows semilogarithmic time-drawdown graphs of four of the
observation wells used in test E. In addition to the corrected draw-
down information obtained during the test, the graphs show the
drawdowns that would have occurred, theoretically, if the aquifer
were (1) artesian, curve A, (2) unconfined, curve B, (3) leaky with
an unlimited source of downward leakage, curve C, (4) leaky
with a limited source of downward leakage, curve D.
Curve A was plotted by using the coefficients of transmissibility
and storage of the highly permeable section of the aquifer, as
determined by the leaky-aquifer method. For this case it was
assumed that the aquifer is infinite, is bounded above and below
by impermeable materials, and receives no recharge during the
pumping period. Curve B was constructed by using a coefficient
of transmissibility 10 per cent higher than the average coefficient of
the test area, as determined by the leaky-aquifer method, and
assigning a storage coefficient of 0.15 (a typical value for unconfined
aquifers). Curve C is a plot of the corrected drawdowns obtained
during the test (solid circles) with the plots extended (open circles)
to conform with ideal leaky-aquifer conditions, which assume that
an unlimited source of supply is available at the surface, and that
no further drawdown occurs after equilibrium is reached. Curve
D is transitional between ideal leaky-aquifer conditions and leaky-
aquifer conditions that prevail in the field, where actual unwatering
of the aquifer occurs. This curve predicts the water-level draw-
downs caused by constant prolonged pumping and no recharge by
rainfall. The graphs in figure 22 show similar drawdown
information for test areas B in Hendry County and D in Glades
County (fig. 18).
In Glades and Hendry counties ground-water levels fluctuate
seasonally, but the average yearly water levels are reasonably
constant (fig. 16). Even in agricultural areas where irrigation is
heavy, the wide cones of depression developed by pumping do not
cause large changes in water levels from year to year. This is due
to the fact that under existing rates of pumping complete
Figure 21. Semilogarithmic time-drawdown graphs of four observation wells
in test area E.
0-0 000--,, -00. 0000 -'000000
URVE D-
WELL 259 CURVE A
GLADES COUNTY
0 --"% --o- v -
ICURVE B
00 0 _110 00 0 00000 00 O OO 00
CURERVE C
1.0 EXPLANATION O--VI
Theoretical drawown, arteson conditions 0 CURVE D
S(no recharge)
CU RVE B
Theoretical draw wn, unconfined conditions CURVE A
2.0 (no recharge)
CURVE C WELL 258
Drowdown,leoky-aqu for conditions GLA C NTY
0 GLADES COUNTY
2.5 Observed draWdown
Theoretical drawdown,constant leakage
3.0 CURVE O
Theoretical drawdown,leaky-aqulfer conditions
5.. (limited leakage)
0
I-
1--f
0
z
O2
"-1
Figure 22. Semilogarithmic time-drawdown graphs of observation wells in
test areas B and D.
FLORIDA GEOLOGICAL SURVEY
replenishment of the aquifers occurs during each rainy season.
Large local drawdowns do not occur, because a large amount of
surface water and shallow ground water is salvaged as a result of
reduction in runoff and evapotranspiration in the areas affected by
pumping.
During dry seasons, 2 or 3 months may elapse without an
appreciable rainfall in Glades and Hendry counties. These rainless
periods may be further prolonged during severe droughts. It is
important, therefore, to estimate the combined effect that long
rainless periods and prolonged, constant pumping would have on
the water level in a given area. A 6-month period was selected as
the maximum duration of such a rainless interval.
Figure 23 shows the maximum drawdowns that would occur
at the end of 6 months, at different distances from a well pumped
at selected rates in each of six test areas. It was assumed that
nonartesian conditions prevailed in each area after 6 months of
pumping; therefore, the graphs were drawn in accordance with
the coefficients of transmissibility shown in table 5, but increased
by 10 percent to include the transmissibility of the semiconfining
beds, and as assumed coefficient of storage of 0.15. If the
coefficient of storage in a given area is less than 0.15, the predicted
drawdowns will be greater than those indicated in figure 23.
When several wells in a large tract are pumped continuously,
the composite drawdown at a particular point can be predicted by
summing the effects that each pumping well would have at that
time. Because drawdown is approximately proportional to the rate
of pumping, the effect of any selected pumping rate can be
interpolated from figure 23.
QUALITY OF WATER
All ground water contains dissolved minerals as a result of the
solvent action of the water as it moves through the rocks. The
character and the quantity of the constituents in the water are
determined by the following: (1) the rate of ground-water flow;
(2) the composition of the materials through which the water
moves; (3) the temperature and pressure of the water; and (4)
the presence of other materials in solution or suspension.
Table 6 is a compilation of complete chemical analyses of water
samples from 23 wells in Glades and Hendry counties. Five wells
penetrate the Floridan aquifer and the rest penetrate shallow
aquifers. Also included are analyses of samples collected at
REPORT OF INVESTIGATIONS NO. 37 59
DISTANCE.IN FEETFROM DISCHARGING WELL
0-- --n----10.X1-..0--- i ,o -0 0 1oooo 3oOo0
C
TEST B TEST E
Computation based on: Computation based on:
T. 130,000 gpd per foot T. 1,055,000 gpd per foot
SS-0.15 S-0.15
t 6 months of pumping t=6 months of pumping
'4--I--- -- 4--- ___ __ _
W TEST C TEST F
SComputation based on: Computation based on:
67 T-125,000 gpd per foot T.555000 gpd per foot
SS-0.15 S-0.15
t-6months of pumping t=6 months of pumping
TESTD TEST G
Computation based on: 5 Computation based on:
T-.120,000 gpd per foot T /275,000 gpd per foot
S-0.15 / .015
St-6 months of pumping / -6 months of pumping
Figure 23. Graphs showing drawdowns expected at different distances from
a well pumped at selected rates in each of six test areas.
multiple depths in a few wells, which indicate the change in quality
of water at different depths in certain aquifers.
In Glades and Hendry counties the water from the Floridan
aquifer generally is highly mineralized, except in northwestern
Glades County. Most of the mineralization is due to chloride salts,
which suggests seawater contamination. The amount of mineraliza-
tion differs with the depth of well, the well construction, and the
location of the well. Some zones in the Floridan aquifer contain
fresher water than others, but in general the deep parts of the
aquifer yield water that is more saline than the shallow zones.
TABLE 0. Analyses Of Water From Wells In Glades And Hendry Counties
(Analymes by U. S. Geological Survey. Chemical constituent. are expressed in part per million,)
GLADES COUNTY
Hardnees
as CaCO,
22 11 667 ...... ...... ...... 118 108 265 .. 848 250 1880 7.7 ..
8-. -51 814 .. -.... ...... 115 172 258 .- -.. 846 252 1,820 7.8 -.
8- 8-51 922 ..115 1 72.25....... 610 170 241 2 UB 48 1,80 7.6 _.
8- 4-561 1,071 .. .. ..... ..... ...... 118 172 280 ... 8. 2 284 1,250 7.6
8- 5-5.61 1,190 ... 18 0.01 741 4.7 111 172 280 0.2 d: 880 832 24 1,40o 7.8 6
28 2-27-51 110 24 .40 ..... 129 18 140 5.5 890 56 218 .6 .9 884 885 66 1,880 7.2 20
27 7.-21-48 85 .......- .02 184 83 166 534 118 195 .- .2 004 470 32 1,540 7.8 80
7-22-48 75 .*... .10 108 40 241 528 129 268 ... .0 1,041 422 0 1,790 7.7 45
28 8-28-48 17 ...- .... .08 156 18 06 484 79 75 .- 8.8 681 448 46 1,090 7.4 65
8-28-48 47 .. .... .05 144 12 175 468 10 280 ..- 852 409 26 954 7.0 90
8-28-48 63 ... .1. .0156 17 88 476 88 112 ... 02 691 460 70 1,150 7.1 42
29 8-81-48 4 .06 ..... 174 1 185 464 154 *218 _- 9.6 950 562 180 1,610 7.8 00
9- 1-48 51 .... .07 78 86 201 884 98 258 ... 1 868 842 28 1,580 7.4 20
9- 1-48 75 ...... .. ...... ... ..... ........... 3874 .. 270 -- ... 1,600 7.4 -
98 12-10-58 86 76 28 .20 0.97 49 12 9.2 1.2 218 4.5 11 .1 .1 227 172 0 864 7.0 7
201 11-25-58 642 79 11 .00 .27 50 40 820 12 166 298 888 1.5 .0 1,260 290 154 2,070 7.7 4
212 10-12-58 87 .... 12 ...... 1.5 148 6.2 81 1.8 358 87 50 .4 2.8 661 895 102 812 7.2 90
227 12-10-58 45 78 88 .04 .14 89 120 514 29 802 140 1,040 .1 .8 2,800 716 468 3,890 7.4 8
TABLE 6. (Continued)
HENDRY COUNTY
8 12-10-53 10 77 6.1 0.06 1.3 123 1.2 21 1.2 880 12 33 0.1 0.1 410 312 0 687 7.5 84
4 4-28-48 90 .... .0 144 10 62 512 17 80 .4 -_ 566 488 18 .- 7.1 22
4-28-48 107 78 .94 .94 144 23 49 540 2.8 78 .4 -- 566 454 6 .. 7.1 15
5 12-10-58 9 75 6.4 .92 1.8 45 2.4 28 1.8 162 12 28 .1 .1 297 122 0 886 6.8 460
14 4-24-48 815 .. .28 66. 88 242 860 126 282 .0 926 298 8 7.5 12
17 8-22-48 601 ... .... .0 70 51 852 122 3851 480 2.4 1.2 1,870 884 284 2,800 7.1 8
20 6-16-42 50 79 ... ... ...... 122 11 45 440 2.9 59 ..- .1 457 860 0 888 -
21 6-17-42 46 .. -- -.. ...... 126 .12 89 466 1 47 -- .1 455 864 0 828 .. -
61 11-24-68 80 77 20 .21 .40 84 80 88 1.0 406 4.0 54 .8 .0 468 888 0 761 7.6 28
156 11-24-58 90 77 14 .01 .24 62 49 880 1.8 188 292 472 1.2 .0 1,400 856 248 2,260 7.6 4
168 11-24-658 68 77 52 .84 .44 108 12 40 8.7 424 16 85 .8 .0 710 819 0 747 7.6 18
200 12-10-58 70 75 26 .07 .21 100 15 89 2.2 416 14 40 .1 .1 470 811 0 747 7.5 45
276 11-24-58 44 78 21 .04 .16 174 12 85 1.6 568 85 128 .0 .1 798 484 22 1,250 7.1 80
278 12-10-58 790 88 14 .03 .11 118 95 514 16 150 245 1,080 1.8 .2 2,800 685 562 8,820 7.5 4
solution at time of analysis.
FLORIDA GEOLOGICAL SURVEY
The water in shallow aquifers in Glades and Hendry counties
is generally of better quality than water in the Floridan aquifer,
except near Lake Okeechobee, in the vicinity of LaBelle, and in the
Devil's Garden area about 18 miles southwest of Clewiston. The
concentrations of calcium and bicarbonate in the shallow aquifers
are usually higher than in the artesian water, but the concen-
trations of sodium, magnesium, sulfate, and chloride are usually
lower.
When the inventory of wells in the counties was made during
1952-53 and 1958-59, samples of water from most of the wells were
analyzed for chloride content. Selected wells were resampled for
partial chemical analysis, which included color, specific conductance,
and total hardness. The results of the partial analyses of water
samples from 205 wells are given in table 7; the results of the
chloride-content analyses are listed in table 8.
HARDNESS
Hardness of ground water is due chiefly to dissolved calcium and
magnesium salts. Water samples from the shallow aquifers in
Glades and Hendry counties range from 13 to 755 ppm in total
hardness. Samples from the Floridan aquifer range from 68 to
1,620 in hardness. Hardness values of more than 120 ppm denote
hard water that usually requires some softening for general use.
Most of the samples of extremely hard water also contain large
amounts of sulfates and chlorides. Tables 6 and 7 show the total
hardness as CaCO, in water samples from wells in the two counties.
TOTAL DISSOLVED SOLIDS
The mineral matter that remains after a quantity of water
is evaporated is approximately equal to the total dissolved solids
in the water. Water from the Floridan aquifer generally contains
more dissolved solids than water from shallow aquifers. The total
dissolved-solids content in ground water in Glades and Hendry
counties ranges from 41 to 4,100 ppm in the shallow aquifers and
from 340 to 5,300 ppm in the Floridan aquifer. Total solids should
be below 500 ppm to meet U. S. Public Health Service standards
(1946). Water containing more than 1,000 ppm probably contains
enough objectionable constituents to impart a noticeable taste and
make the water unsuitable for many purposes.
REPORT OF INVESTIGATIONS NO. 37 63
TABLE 7. Partial Analyses of Water from Wells in Glades and Hendry
Counties
GLADES COUNTY
1 5- 6-53 120 860 430 1,4300 60
0
3 5- 6-53 48 1;300 255 2,240 90
S5 30 26 63
S 4-29-53 96 77 610 288 1,020 24
0 4-29-53 173 320 284 540 25
S1 5 5 1
5- -3 35 38 3 3
2 5- 8-53 804 12,400 645 4,020 9
12 5- 6-53 120 81 860 430 1,430 60
13 5- 6-53 48 80 1;,00 255 2,240 90
26 4-29-53 120 380 276 633 19
37 4-29-53 96 77 610 288 1,020 24
40 4-29-53 173 320 284 540 25
42 4-29-53 102 75 350 232 579 19
45 4-29-53 112 76 570 330 950 35
47 4-29-53 106 79 200 159 331 25
48 5- 1-53 325 77 380 236 630 22
49 5- 1-53 500 79 1,100 380 1,850 20
50' 1-53 85 76 310 186 511 30
52 5- 1-53 491 81 1,100 310 1,780 110
53 5- 1-53 495 80 1200 330 2,010 55
55 5- 1-53 62 -7 430 146 722 11
56 4-30-53 700 79 410 170 688 28
57 4-30-53 22 73 130 86 216 18
58 4-30-53 608 76 340 156 562 30
59 5- 1-53 593 400 180 670 45
60 5- 1-53 30 0 14 69 50
66 5- 1-53 25 200 134 339 65
71 4-29-53 34 75 690 300 1,150 28
73 4-29-53 22 76 450 228 754 20
76 4-29-53 410 76 430 266 722 18
77 4-29-53 21 75 45 14 78 99
79 5-13-53 70 74 80 40 136 75
s0 4-29-53 25 765 381 111 10
83 7- 8-53 618 7 350 68 580 7
85 5- 1-53 47 1 45 13 77 55
86 5- 1-53 300 76 340 210 568 25
90 5- 1-53 35 380 186 625 25
93 5- 1-53 86 2200 180 368 20
94 5- 1-53 46 75 340 308 569 14
98 5- 1-53 55 350 276 575 34
102 5- 1-53 41 380 190 636 55
106 5- 1-53 25 77 350 102 585 110
109 5- 1-53 5006 870 205 1,450 10
110 5- 1-53 508 78 1,100 160 1,800 19
112 5- 1-53 50 74 400 204 662 60
116 5- 1-53 750 -_ 1.300 545 2,250 22
118 5- 1-53 17 75 240 190 404 220
122 5- 1-53 70 380 132 634 110
123 5- 1-53 1,200 5,300 725 8,780 25
126 5- 1-53 25 75 320 228 534 180
128 5- 1-53 100 75 540 364 893 90
130 5-13-53 162 74 520 210 873 45
136 5- 6-53 85 74 1,500 240 2,510 45
139 5- 6-53 86 75 810 185 1,350 55
FLORIDA GEOLOGICAL SURVEY
TABLE 7. (Continued)
5- 6-53
5- 6-53
5- 6-53
5- 6-53
5- 6-53
5- 6-53
5- 6-53
5- 6-53
5- 6-53
5- 6-53
5- 6-53
5- 6-53
5- 6-53
5- 6-53
5- 6-53
5- 6-53
5- 6-53
5- 6-53
5- 6-53
4-30-53
4-30-53
5- 6-53
4-29-53
5-13-53
5-13-53
5-13-53
5- 6-53
5- 6-53
5-13-53
5-13-53
5- 8-53
5-13-53
5- 8-53
5- 8-53
5- 8-53
5- 8-53
5- 8-53
4-29-53
4-29-53
50
40
e00
32
56
600
48
30
6
20
102
26
52
40
105
110
101
100
73
186
68
68
850
642
65
65
40
1,500
1,250
44
20
26
100
42
45
53
500
5
0
o .0
s" S
C.
0-
E g
> E IW
0 3.,
n a a
80
79
74
77
81
79
79
86
81
__
76
79
75
80
72
920
1,600
2,500
430
4,100
870
1,100
2,200
620
960
3.400
640
950
970
1,100
790
1,100
3,100
1,500
430
440
660
1.400
1,200
540
1,200
3,800
550
4.800
1.100
470
570
240
2.600
360
1,000
1,600
1,500
65
360
245
685
144
550
305
755
570
340
485
460
374
345
375
260
210
310
350
230
338
340
226
470
290
476
450
730
380
1,620
435
352
426
158
730
242
475
575
430
22
,u 0
1,40
1,760
3,70
go
070
C .O
1,540
2.640
4,110
723
6.770
1,450
1,760
3,750
1.030
1,600
5,650
1,070
1,580
1,610
1,800
1,310
1,830
5,110
2,500
716
726
1,100
2,390
2.000
894
1,960
6,400
928
7,980
1,760
776
947
402
4.300
598
1,660
2,610
2,440
107
0
45
35
19
220
60
30
110
45
75
60
45
40
60
75
50
40
55
90
60
50
40
65
40
12
200
110
15
65
20
5
100
110
75
30
70
45
90
10
60
HENDRY COUNTY
2 4-30-53 650 80 1.300 330 2,210 7
12 5- 8-53 105 _. 670 394 1,120 60
15 5- 8-53 130 370 214 624 45
17 4-30-53 601 81 1,300 370 2,230 14
19 5- 7-53 80 590 336 979 50
REPORT OF INVESTIGATIONS No. 37 65
TABLE 7. (Continued)
u
o o
0
2Y u u
a fa ao 0w -
*w o? .^
w 00
_ Ei __ 0B
t~~7 S 14;
o '8 ^ iE
a Q Q i p __
46
51
52
54
55
58
60
62
63
66
71
72
74
75
77
79
80
81
83
84
85
87
88
89
90
92
97
103
105
106
107
108
111
112
114
115
116
119
120
121
127
128
131
136
140
141
142
145
149
5- 7-53
5- 7-53
5- 7-53
5- 1-53
5- 7-53
5- 7-53
5- 7-53
4-29-53
4-29-53
4-29-53
5- 1-53
5- 1-53
5- 1-53
5- 1-53
5- 1-53
5- 1-53
4-29-53
4-29-53
4-29-53
5- 1-53
4-29-53
4-30-53
4-29-53
5- 1-53
4-29-53
4-29-53
4-29-53
4-29-53
4-29-53
4-29-53
4-29-53
4-29-53
5- 1-53
5- 1-53
5- 1-53
5- 1-53
5- 1-53
5- 1-53
5- 1-53
5- 7-53
5- 1-53
5- 1-53
4-30-53
4-30-53
4-30-53
4-30-53
4-30-53
4-30-53
4-30-53
1,465
68
1,300
100
50
995
123
580
115
300
715
820
125
85
250
750
90
700
1,536
30
390
69
117
95
664
800
208
122
45
60
800
700
137
26
700
46
76
100
100
68
74
80
80
83
83
79
84
82
79
82
79
76
84
84
80
76
79
83
79
78
80
87
78
78
76
78
78
82
81
78
84
86
76
80
79
78
75
81
76
2,300
2,400
290
2,900
920
660
2,300
430
1,000
470
730
1,800
1,900
1,100
2,200
640
500
2,400
2,400
2,300
2,700
1,400
1,400
2,600
520
490
340
1,300
1,300
1,100
1,100
470
2,100
1,700
1,600
2,200
2,800
810
310
2,600
500
1,300
600
1,200
1,400
1,300
1,100
570
570
760
767
200
920
395
310
795
260
270
202
338
425
485
455
795
290
262
510
550
720
455
370
390
995
280
142
260
235
365
255
245
264
740
635
640
890
1,030
355
250
715
188
475
226
345
355
360
345
232
262
3,840
3,970
477
4,880
1,540
1,070
3,760
716
1,720
790
1,220
2,940
3,090
1,870
3,580
1,060
829
4,010
4,060
3,910
4,500
2,250
2,250
4,320
871
823
562
2,200
2,200
1,870
1,790
789
3,450
2,800
2,590
3,740
4,600
1,350
509
4,260
837
2,240
1,000
1,960
2,310
2,160
1,860
947
947
FLORIDA GEOLOGICAL SURVEY
TABLE 7. (Continued)
0
1
I~~ .2 I 6
-4 0
> E Q
2S 2. 0 0 B
0 >2 o Ei ^
0 60
S20 c |6
6. 0ca]
__ a cj Q
^~C Q Q i Q
150
151
152
154
155
156
159
161
166
167
170
171
172
175
176
177
180
181
182
184
185
186
187
188
190
194
197
198
199
201
203
204
205
206
207
210
211
212
214
215
216
220
221
223.
224
225
227
236
241
4-30-53
4-30-53
4-20-53
4-30-53
4-30-53
4-30-53
4-30-53
4-30-53
4-30-53
4-30-53
4-30-53
4-30-52
4-30-53
4-30-53
5- 1-53
4-30-53
4-30-53
4-30-53
4-30-53
4-30-53
4-30-53
4-30-53
4-30-53
4-30-53
3-11-53
5- 7-53
5- 8-53
5- 8-53
4-30-53
4-30-53
5- 7-53
5- 7-53
5- 7-53
5- 7-53
5- 7-53
5- 7-53
5- 7-53
5- 7-53
5-12-53
5- 7-53
5- 7-53
5- 7-53
5-13-53
5- 8-53
5- 8-53
5- 8-53
5-13-53
5- 8-53
5-13-53
30
28
22
18
80
90
744
84
80
80
98
40
145
140
135
18
20
92
60
180
99
78
100
48
326
45
47
90
180
15
112
90
160
100
100
26
42
140
45
244
328
112
12
40
15
36
115
38
78
78
78
75
77
76
74
76
--.
74
75
72
77
75
310
500
680
1,300
1,300
1,300
1,900
470
540
1,300
790
540
830
570
650
1,600
360
290
740
620
590
430
370
520
390
920
590
570
470
460
430
430
670
310
820
1,000
1,400
400
1,800
2,900
1,700
1,000
1,100
590
640
470
650
490
610
168
296
220
445
370
365
330
206
242
350
355
132
330
236
180
345
252
218
285
244
114
290
202
296
88
165
276
248
412
224
212
152
292
248
200
420
530
208
260
610
250
160
180
316
172
200
156
156
148
508
846
1,130
2,230
2,220
2,160
3,100
790
907
2,090
1,320
907
1,390
941
1,090
2,700
596
485
1,230
1,020
977
723
613
873
654
1,540
980
947
787
771
711
713
1,110
523
1,360
1,680
2,390
673
3,000
4,850
2,750
1,590
1,870
987
1,070
775
1,090
823
1,020
19
22
15
16
15
6
22
27
21
16
25
65
20
15
35
45
110
25
27
50
21
27
40
100
45
45
55
100
70
120
55
120
60
55
65
100
30
45
40
50
55
55
220
50
80
55
100
45
REPORT OF INVESTIGATIONS NO. 37
TABLE 7. (Continued)
248
250
252
258
263
265
268
269
270
271
272
273
274
275
278
5- 8-53
5- 8-53
5- 8-53
5-12-53
5-12-53
5-12-53
4-30-53
4-30-53
5- 7-53
5-12-53
5- 7-53
5- 8-53
5-13-53
5- 1-53
7- 7-53
.6
0.
'0
.0 C:
o,
II
A
4 -
>B
M
gg
610
740
580
550
1,200
700
430
1,900
520
470
1,700
1,700
580
1,700
2,200
0
cu
'6) 0
gEh
0
Cn
0.
E2
a
m
1,010
1,230
972
914
1,990
1,170
708
3,170
860
774
2,800
2,850
962
2,850
3,700
SPECIFIC CONDUCTANCE
Specific conductance is a measure of the ability of water to
conduct an electric current. Water containing a low mineral content
is resistant to the flow of electricity, whereas highly mineralized
water conducts an electric current with relative ease. Therefore,
the values for specific conductance can be used to estimate the
concentration of dissolved solids in water. Figure 24 shows the
relation of total dissolved solids in water samples to specific
conductance where both values have been determined in the
laboratory. The data show that the dissolved solids can be approxi-
mated by multiplying the specific conductance by 0.6. Specific
conductance is .usually higher in the deep -artesian water than in
the water from the shallow aquifers; it reaches a maximum of more
than 8,700 micromhos in well 123 in Glades County. In table 7 the
values for total dissolved solids were estimated from specific
conductance by multiplying by the 0.6 factor.
68 FLORIDA GEOLOGICAL SURVEY
EXPLANATION
SI a I J I
DEEP ARTESIAN WELL
WELL IN SHALLOW AOUIFER
*/-
4oo-i--i--i--i---- -- --- ---- -: -- -7
o 1000 .000 0-00 4.000 5,00
SPECIFIC CONDUCTANCE (MICRO.HOSAT 25C)
Figure 24. Graph showing the relation between specific conductance and total
dissolved solids in water samples from Glades and Hendry counties.
,1000,000 -0 4-000 5-000
HYDROGEN-ION CONCENTRATION (pH)
The pH is a measure of the hydrogen-ion concentration and
indicates whether the water is acid or alkaline. On a scale of 0 to
14, pH values higher than 7.0 indicate alkalinity and values lower
than 7.0 indicate acidity. All samples analyzed, except one, had
pH values of 7.0 or greater; the sample from well 22 in Glades
County had a pH of 6.9. The measured pH values are shown in
table 6.
IRON (Fe)
Water containing more than 0.3 ppm of iron will stain plumbing
fixtures, clothes, and other objects with which it comes in contact.
High concentrations of iron also cause the water to have a
disagreeable taste. Iron in a clear ground-water solution is in the
ferrous state until the water is exposed to the oxygen in the
atmosphere, then the iron is oxidized to the ferric state and
precipitates as the insoluble hydroxide or oxide of iron. The iron
precipitate may then be removed by filtration. Water samples from
the artesian aquifer contained less than 0.3 ppm of iron. The iron
content of water from the shallow aquifers differs from place to
place and at different depths within the aquifer. It ranged from
0.11 to 1.5 ppm (table 6).
REPORT OF INVESTIGATIONS NO. 37
CALCIUM (Ca) AND MAGNESIUM (Mg)
Dissolved calcium and magnesium salts are responsible for
most of the hardness of water. Much of the water-bearing material
underlying Glades and Hendry counties is composed of limestone
and a lesser amount of dolomite. These carbonate rocks are the
sources of calcium and magnesium in the ground water in the area.
The concentration of calcium ranged from 42 to 136 ppm in water
samples from the Floridan aquifer and from 49 to 174 ppm in water
samples from the shallow aquifers. The concentration of magnesium
ranged from 36 to 105 ppm in the Floridan aquifer and from 1.2
to 120 ppm in the shallow aquifers.
The shallow ground water usually contains less magnesium than
the artesian water and the amount of magnesium is usually less
than the calcium. An exception is shown in the analyses of water
from well 227 in Glades County northwest of Clewiston and from
well 276 in Hendry County in Clewiston (table 6). The wells are
about 4 miles apart and about 45 feet deep. The chemical analyses
of the samples show wide differences in chloride content, total
dissolved solids, sodium, calcium, and magnesium. The ratio of
magnesium to calcium in well 227 is of interest; the content of
magnesium is considerably higher than that of calcium, unlike other
samples from the shallow aquifer. As sea water contains more
magnesium than calcium, this may indicate the presence of sea
water which was trapped in the aquifer during high stands of the
sea in Pleistocene time. No dolomitic limestones are known to
occur in the shallow materials, thus discounting the solvent action
of ground water on the shallow materials as the source of
magnesium. The high chloride content of water is further
indication of contamination by sea water.
SODIUM (Na) AND POTASSIUM (K)
The quantity of sodium plus potassium in ground water in
Glades and Hendry counties ranges from 10.4 to 543 ppm in the
shallow aquifers and from 145.5 to 530 ppm in the Floridan
aquifer; the concentration of sodium greatly exceeds that of
potassium. Moderate amounts of these constituents have no effect
on the palatability of drinking water, but large amounts render
the water unsuitable for most uses. The ratio of the quantity of
sodium to the total quantity of sodium, calcium, and magnesium
is important when the water is to be used for irrigation. Large
FLORIDA GEOLOGICAL SURVEY
quantities of sodium tend to decrease the permeability of soils, and
water containing more than 50 percent sodium may injure the soil
and crops.
Figure 25 shows the suitability of water for irrigation, as
determined by Wilcox (1948, p. 25-26) and utilized by Visher (1952,
p. 15-17) in an arid area. Most of the water samples from the
shallow aquifers are in the range from excellent to permissible,
but many of the samples from the Floridan aquifer are in the
doubtful or unsuitable range. However, the chart assumes little or
no flushing of the soil by rainfall. In an area of plentiful rainfall,
such as south Florida, the sodium content of the soil probably
would not accumulate in quantities harmful to most crops.
BICARBONATE (HCO,)
The amount of bicarbonate in the ground water in Glades and
Hendry counties ranges from 138 to 563 ppm in the shallow
aquifers and from 109 to 166 ppm in the Floridan aquifer. The
bicarbonate results from the solvent action of ground water
containing carbon dioxide gas on carbonate rocks. Much of the
bicarbonate can be readily removed by relatively simple water
treatment.
SULFATE (SO,)
Concentrations of sulfate in ground water in Glades and Hendry
counties range from 1 to 292 ppm in the shallow aquifers and from
126 to 351 ppm in the Floridan aquifer. The sulfate radical is not
very important in domestic water supplies unless it exceeds 500
ppm, in which case it may have a laxative effect. The U. S. Public
Health Service recommends that public water supplies contain
not more than 250 ppm of sulfate. Some sulfate compounds in
water cause hardness that is difficult to reduce by treatment.
CHLORIDE (Cl)
Water containing chloride in excess of 250 ppm is considered by
the U. S. Public Health Service to be unsuitable for public drinking
supplies, except in areas where better quality water is not available.
Water containing more than 750 ppm of chloride may damage
many plants and shrubs. Chloride concentrations in ground water
in Glades and Hendry counties range from 7 to 2,280 ppm in the
shallow aquifers and from 34 to 4,240 ppm in the Floridan aquifer.
REPORT OF INVESTIGATIONS NO. 37
HE HENDRY
EXCELLENT GOOD DOUBTFUL UNSUITABLE
0 500 1,000 1,500 2,000 2,500 3,000 3,500 4,000
SPECIFIC CONDUCTANCE (MICROMHOS, AT 25C)
Figure 25. Graph showing the suitability of ground water for irrigation.
(after Wilcox 1948, p. 25-23)
High-chloride water is corrosive and may rust holes in the casing
through which subsurface leakage from artesian wells can occur.
Chloride cannot be removed by ordinary water treatment.
Water samples for chloride-content analysis were obtained from
most of the wells inventoried in the two counties, and the analytical
results are listed in table 8. Figure 26 shows the chloride content
FLORIDA GEOLOGICAL SURVEY
I 278
S
8i5 *872
4 29E R 29E R0OE-
EXPLANATION
Chloride content 4
0 O (ports per million)
O I
No. 0-100
e epth,in feet 3
101-250
T
47-
251-500 s
O
501-1000 _
1001-2000 T I
+ TI
More than 2000 sI
SCALE IN MILES ._
2 0 2 4 6 8 10 R31E
DORE HAVEN
QDES COUI
UNTY
*1039
HENRY J. COUNTY
R32E R33E
Figure 26. Glades and Hendry counties showing the chloride content of water
samples from wells tapping the Floridan aquifer, 1952-53, 1958.
LAKE
ECHOBEE
S
4I
CLE'WSTON
R34E
v
REPORT OF INVESTIGATIONS NO. 37 73
of water samples from wells tapping the Floridan aquifer in these
counties. Most of the data shown were obtained during 1952-53;
additional information was obtained during 1958 in more recently
established agricultural and grazing lands.
The data in figure 26 suggest that the deeper wells generally
yield the water of poorest quality. Potable water is available from
the Floridan aquifer in central Glades County in the vicinity of
Palmdale, and good-quality water can be expected northward and
northwestward from central Glades County into Highlands County.
Also, wells reportedly ranging in depth from 390 to 450 feet
immediately north of LaBelle yield potable water. These wells
probably tap the uppermost limestone layers of the Floridan
aquifer. A group of artesian wells 8 miles east of LaBelle and
three wells near the northern boundary of Glades County yield
water that contains less than 250 ppm of chloride. It is possible,
however, that increased use of water in those areas may cause a
slow deterioration of the quality as a result of upward movement
of water of higher chloride content within the aquifer.
The data shown in figure 27 indicate that the shallow aquifers
in Glades County yield water of low chloride content except in areas
adjacent to Lake Okeechobee. Figure 28 shows chloride data for
EXPLANATION I
2510-00 S "ENU. I
So L
romwels t g s w uirs, 1
501 000 .. .. ..... .. .
o......... .3. -- -
oOS COT !o sfA- 1.31
40. 1 .. ... .. .
i I o '^
,' : o. w ,*S ........
.,d~~f~b~ib~t., / f A %rA
from wells tapping shallow aquifers, 1952-53.
FLORIDA GEOLOGICAL SURVEY
Figure 28. Part of eastern Glades County showing the chloride content of
water samples from wells tapping shallow aquifers, 1952-53, 1959.
the area north of Lakeport where there is a large concentration of
shallow wells. It is apparent that most of the shallow water in
the Lakeport area does not meet the standards for public supplies.
Figure 29 is a map of Hendry County showing the chloride
content of water samples from wells tapping shallow aquifers.
The distribution of the chlorides suggests isolated sources of con-
tamination by salty water. Figure 30 shows the chloride content of
water from selected wells in the Clewiston area.
FLUORIDE (F)
The fluoride concentration in ground water in Glades and Hendry
counties ranges from 0 to 1.2 ppm in the shallow aquifers and from
0.2 to 2.4 ppm in the Floridan aquifer. Minor quantities of fluoride
in drinking water are beneficial in decreasing tooth decay among
children (Black and Brown, 1951, p. 15). However, quantities in
excess of 1.5 ppm may result in a condition known as dental
fluorosis, a mottling of the tooth enamel in chlidren.
SILICA (SiO,)
The amount of silica in ground water in Glades and Hendry
counties ranges from 6.1 to 56 ppm in the shallow aquifers and from
11 to 14 ppm in the Floridan aquifer. Silica content is of relatively
REPORT OF INVESTIGATIONS No. 37 75
r-GLADES COUNTY
-
. f ,i I
Figure 29. Henry County showing the chloride content of water samples
the shallow aquifer. A concentration above 50 ppm is very
undesirable in drinking water, because it may cause cyanosis in
Hydrogen sulfide is found in much of the shallow water and all
I i4
the deep artesian water of the area. Hydrog en sulfide causes a
distinct taste and odor which has given the water the name "sulfur
water." Hydrogen sulfide is not generally analyzed because it is a
H e ulfu f e s o we
B r -i COUNTYR30ER COUNT _; _
e EXPLA" TION in y
Figure 29. Hendry County showing the chloride content of water samples
from wells tapping shallow aquifers, 1952-53, 1958.
little importance except in the formation of boiler scale, and was
not determined in most analyses.
NITRATE (NO.)
Nitrate concentrations range from o to 1.2 ppm in the water
from the artesian aquifer, and from 0 to 9.6 ppm in the water from
distinct taste and odor which has given the water the name "sulfur
water." Hydrogen sulfide is not generally analyzed because it is. a
FLORIDA GEOLOGICAL SURVEY
i ---- ~ ---- 1- ^ ^, ^
e 1 -261 262 1
250 4246 244 240 l 3
2 r, s 3 22 25
) 253 5 225
Figure 30. Clewiston area showing the chloride content of water samples
from wells tapping the shallow aquifers, 1952-53.
volatile gas held in solution and much of it escapes upon exposure
to air. Most of the gas can be removed by aeration.
SALT-WATER CONTAMINATION
In southern Florida the major causes of soal-water contami-
gre Colewstn area htoewin the Grulf t of M water msamles
nation of aquifers are as follows: (1) direct encroachment from
surface salt-water bodies along coastal areas where the fresh-water
head is not sufficient to retard encroachment; (2) upward leakage
of relatively salty artesian water, under high pressure, through
open well bores or across semiconfining layers; and (3) incomplete
flushing of sea water that entered the aquifers during high-sea-level
intervals of the Pleistocene Epoch when southern Florida was
covered by the ocean.
Direct encroachment: The only possible source of direct sea-
water encroachment in Glades and Hendry counties is the
Caloosahatchee River. The Ortona Lock is closed during extended
dry periods and sea water from the Gulf of Mexico may move
inland to the downstream side of the lock. However, the banks and
the riverbed along most of the reach downstream from Ortona
are composed of relatively impermeable clay and marl, which tend
to prevent lateral or downward seepage from the channel. Also,
ground-water levels adjacent to the river usually are considerably
higher than the river stage (fig. 17), and the normal direction of
ground-water flow is toward the river. Therefore, direct sea-water
encroachment into aquifers in Glades and Hendry counties is
negligible.
Upward leakage: In most of Glades and Hendry counties the
deep parts of the Floridan aquifer contain water that is saltier
than water in the shallow parts. In some places thin zones
REPORT OF INVESTIGATIONS NO. 37
containing fairly fresh water may underlie salty zones, but if the
open-hole section of the well is deepened, additional zones containing
salty water will be tapped (see table 4).
In most areas of the two counties the pressure in the deep zones
of the aquifer is greater than that in shallow zones. If a well is
so constructed that its open bore section penetrates upper fresh
zones and deeper salty zones, the deep salty water under high
pressure can move upward through the well bore and enter the
shallow fresh-water zone. The amount of interchange of water will
depend upon the permeability of the rock and the pressure
differential between the two zones. It appears, therefore, that well
construction is an important factor in the quality of the water
yielded by a well in the Floridan aquifer.
Contamination by upward leakage within the Floridan aquifer
probably is accelerated where the piezometric surface is
lowered as a result of heavy discharge by wells. High pressure
in deep zones will cause saline water to move upward into zones
of fresh water that are tapped by wells. The high mineralization
of the water from artesian wells in LaBelle and southwest of
LaBelle shown in figure 31 may be due, in part, to the decline of
the piezometric surface in this general area, as shown in figure
14. It is possible that the initial flowing wells drilled in this area
yielded fresher water than that shown in figure 31.
--------
I HENRY COUNTY
soL BELLE
s Sijr* j/,-.
I
I 327
75 EXPLANATION
S3 t5 o na Chloride content
318 319 O s 76 (parts per million)
45115 89 292
ST Well No, 0
T Depthin feet 0o100
2 321 10 101 250
251-500
501-1000
ISCAL IN MILES 0
0 I 2 More than 1000
Figure 31. Part of northwestern Hendry County showing the chloride content
of water samples from wells tapping deep and shallow aquifers, 1952-53, 1958.
FLORIDA GEOLOGICAL SURVEY
The salt-water contamination in the shallow aquifer in LaBelle
was probably caused by upward and lateral leakage in the vicinity
of wells penetrating the Floridan aquifer. Figure 32 shows the
chloride content of water from shallow wells in and adjacent to
LaBelle. Most of the shallow wells in LaBelle range in depth from
60 to 120 feet below the land surface and are developed in shelly
limestone layers.
The seven deep artesian wells within the populated area south
of the Caloosahatchee River probably were drilled before 1930
(fig. 11). It was reported that casings in most of these wells were
seated in a limestone layer at a depth of about 80 feet and that
an open bore was drilled to 600-800 feet. The piezometric surface
in these wells is at least 25 feet above the land surface, whereas
the water level in the shallow wells is below the land surface.
Therefore, direct connection probably exists between the open bore
of the deep wells and the limestones below 80 feet in the shallow
aquifer. Most of the deep wells in LaBelle are not in use or are
used sparingly, so that the discharge valves are cut off for long
periods. As a result, the pressure differential between the deep
well bores and the shallow limestones is consistently high, and
upward discharge into the shallow limestone occurs at a constant
rate.
Well 17 in LaBelle, immediately south of the Caloosahatchee
River, taps the Floridan aquifer, and for many years was used as
the central water supply for the town. Distribution lines extend
from the well probably as far south as State Highway 80. These
distribution lines are known to have developed leaks and the entire
system is a probable source of local contamination of the shallow
aquifer. The pattern of the chloride contours shown in figure 33
suggests that the five deep artesian wells (within the 400-ppm
contour line) between the Caloosahatchee River and State Highway
80 and the subsurface water-distribution system from well 17 may
be the principal sources of contamination. Further evidence to
support this is shown by a comparison of the analyses of water
samples from well 17 (602 feet deep) and well 156 (90 feet deep),
170 feet south of well 17, as shown in table 6. The analyses are
nearly identical.
The pattern of the distribution of the chloride contents and
isochlor contours in figure 33 negates the possibility that the
Caloosahatchee River is the source of contamination. The contour
pattern shows that contamination extends beneath and across the
river and further substantiates the conclusion that the river does
not appreciably affect the drainage of the shallow aquifer.
REPORT OF INVESTIGATIONS No. 37
Figure 32. LaBelle showing the chloride content of water samples from wells
tapping the shallow aquifer, 1952-53.
Much of the salt-water contamination in the shallow aquifer
along the Caloosahatchee River west and southwest of LaBelle may
be caused by conditions similar to those causing the contamination
in LaBelle. The water level of well 112, a 45-foot well near the
Lee County boundary, was 7.5 feet above the land surface in May
FLORIDA GEOLOGICAL SURVEY
I II LA BELLE II CITY LIMITS II I
Figure 33. LaBelle showing (by isochlor lines) areas of equal chloride content
of water from the shallow aquifer, 1952-53.
1958. This high water level is probably due to upward and lateral
leakage from immediately adjacent artesian wells which have been
capped at the surface and abandoned.
Incomplete flushing: The high mineralization of. the water
contained in the Floridan aquifer in southern Florida probably is
due to connate sea water which remained in the materials when
they were deposited, or to sea water that entered the aquifer when
REPORT OF INVESTIGATIONS NO. 37
much of peninsular Florida was covered by the ocean during the
Pleistocene Epoch. The shallow aquifers in Glades and Hendry
counties also were filled with sea water when the area was last
covered by the ocean, but since the seas receded rainfall has been
flushing salts from the shallow aquifers. Flushing has been more
extensive in the shallow materials than in the Floridan aquifer,
but Love (Parker and others, 1955, p. 818) indicated that saline
water and the residual salts have never been completely flushed
in most of the Everglades, particularly near the borders of Lake
Okeechobee. Figures 27 and 28 show the high salinity of the
shallow ground water adjacent to Lake Okeechobee.
Flushing of salts would be most rapid where the infiltration of
rainfall is rapid and where ground-water movement is not impeded.
The rather uniformly low permeability of the shallow sediments
may be one of the chief reasons for the saline ground water along
the borders of Lake Okeechobee. Also, the low ground-water
gradient throughout the area may be an important factor in the
slow flushing process. Most of the potential aquifer recharge by
rainfall in the area probably is lost by sheet flow and evapo-
transpiration, and apparently only minor quantities can infiltrate
to the permeable sections. Differences in permeability may partly
account for the variations of chloride content in areas where
upward leakage from the Floridan aquifer is not a factor.
UTILIZATION OF GROUND WATER
Ground water in Glades and Hendry counties is used for irriga-
tion, public and domestic supplies, stock watering, and, to lesser
extent, industries and air conditioning.
IRRIGATION
The quantity of ground water used for irrigation in Glades and
Hendry counties far exceeds that used for other purposes. In
addition to the huge sugar plantations that border Lake Okeechobee
near Clewiston, large areas are devoted to the production of truck
crops grown during late fall, winter, and spring. In areas near
surface-water bodies irrigation is practiced by use of shallow
ditches from the surface sources. Other areas, however, depend
on ground-water sources.
Water for irrigation is obtained from the Floridan aquifer
and the shallow aquifers. The source used depends on the crops
to be grown. Tomatoes and cucumbers will tolerate water with a
FLORIDA GEOLOGICAL SURVEY
fairly high concentration of dissolved solids, whereas beans and
some other crops will not. Irrigation by use of shallow wells is a
fairly recent development in the area and will probably increase.
The largest increase in the use of irrigation water has taken place
in Hendry County, south of LaBelle, and in the Big Cypress Swamp-
Devil's Garden area.
MUNICIPAL SUPPLIES
LaBelle and Moore Haven are the only municipalities in the two
counties that used ground water for public supplies in 1959. The
supply for LaBelle was obtained from well 17, which penetrates
the Floridan aquifer. The water was piped directly from the well
through distribution lines to the consumers and received no treat-
ment. The quality of the water is poor and most of the residents
have resorted to drilling individual shallow wells. In the central
part of LaBelle the shallow aquifer does not produce water of
acceptable quality because of salt-water contamination (fig. 33).
Chemical analyses of water samples in the LaBelle area indicate
that ground water of good quality can be obtained away from the
central part of the town, where the shallow water is low in
chloride, relatively low in total dissolved solids, but high in
hardness. The hardness can be reduced by treatment, and aeration
and filtration will remove much of the iron and hydrogen sulfide
present in solution. In 1959 the residents of LaBelle authorized
a study to develop a public water supply from the shallow aquifer
south of town.
Moore Haven obtains its water supply from an 8-inch well
drilled to a depth of 87 feet. A 5-horsepower deep-well turbine
pump is capable of withdrawing 285 gpm from the well.
Approximately 85,000 to 100,000 gallons of water are used daily
by the town. This includes water for household use, industrial
use, and lawn irrigation. Water treatment consists of aeration,
reduction of hardness, and chlorination.
None of the other communities in the area are supplied by
public ground-water systems. In agricultural areas and small
population centers such as Palmdale, Lakeport, and the outskirts
of LaBelle, nearly every home has its individual water supply. A
similar situation exists in suburban areas west and southeast of
Clewiston. The city of Clewiston obtains its municipal supply from
Lake Okeechobee.
REPORT OF INVESTIGATIONS NO. 37
OTHER USES
A small quantity of ground water is used for industrial and
cooling processes, and a few commercial establishments in Clewiston
operate wells for air conditioning. A shallow well is used in running
condensers at the ice plant at Moore Haven. Several packing
houses in the farming areas use a considerable quantity of ground
water in the washing, processing, and packing of truck crops.
These wells are operated for only a few weeks during the year.
Ground water is used also for stock watering.
SUMMARY
The most productive aquifer in Glades and Hendry counties is
the Floridan aquifer, which yields water by natural flow to most
parts of the area. Wells penetrating this aquifer range in depth
from 400 feet to more than 1,200 feet and generally yield 200 gpm
or more.
The chloride concentration in water from wells tapping the
artesian aquifer at depths of 400 to 700 feet ranges from 40 ppm
to more than 2,000 ppm. The aquifer underlying Glades County
in the vicinity of Lake Okeechobee yields water with a chloride
content ranging from 700 to more than 1,200 ppm. Artesian water
containing less than 100 ppm of chloride, can be obtained in north-
western and northern Glades County. In general, the chloride
content of the water increases southward and southeastward.
Permeable zones in the aquifer occur down to more than 1,200
feet. Throughout most of the area the lower limestones yield highly
mineralized water, except in northwestern and northern Glades,
County where relatively fresh water can be obtained in the deep
part of the aquifer.
Shallow sources of ground water are being developed in both
Glades and Hendry counties, especially in those areas where the
artesian water is highly mineralized. Wells penetrating shallow
aquifers generally range in depth from 50 feet to more than 300
feet.
The permeable limestone of the Tamiami Formation in southern
Hendry County is the most productive shallow aquifer in the area.
Wells penetrating this aquifer range in depth from about 40 feet in
areas a few miles east of Immokalee to about 120 feet or more
south of the Devil's Garden. The lateral extent and the total
thickness of this aquifer cannot be determined with present data;
however, the aquifer is known to extend as far north as the Felda
FLORIDA GEOLOGICAL SURVEY
area, but has not been noted in wells in the immediate Immokalee
area. The aquifer apparently dips to the east and to the south.
Six-inch wells penetrating this limestone aquifer yield good
quality water at a rate of more than 1,000 gpm with little draw-
down. Water levels are within a few feet of the land surface, and
pumping costs are relatively low.
In central and northern Hendry County and in Glades County
the shallow aquifers are composed of thin local limestones and
shell beds in the Tamiami and Hawthorn Formations. These
aquifers range in depth from 50 feet to about 175 feet and yield
moderate amounts of water. The water usually contains less than
400 ppm of chloride, except in areas adjacent to Lake Okeechobee
and along the Caloosahatchee River westward from LaBelle. In
and southwest of LaBelle the shallow aquifer is contaminated by
artesian water under high pressure leaking upward along open-well
bores and laterally into permeable beds of low pressure.
Quantitative tests show that the coefficient of transmissibility
of the shallow aquifers ranges from 70,000 gpd/ft to 1,070,000
gpd/ft, and that the coefficient of storage ranges from 0.00015 to
0.0014.
REPORT OF INVESTIGATIONS NO. 37
REFERENCES
Applin, E. R. (also see Applin, P. L.)
1945 (and Jordan, Louise) Diagnostic Foraminifera from subsurface
formations in Florida: Jour. Paleontology, v. 19, no. 2, p. 129-148.
Applin, P. L.
1944 (and Applin, E. R.) Regional subsurface stratigraphy and struc-
ture of Florida and southern Georgia: Am. Assoc. Petroleum
Geologists Bull., v. 28, no. 12, p. 1673-1753.
1951 Preliminary report on buried pre-Mesozoic rocks in Florida and
adjacent states: U. S. Geol. Survey Circ. 91.
Bishop, E. W.
1956 Geology and ground-water resources of Highlands County,
Florida: Florida Geol. Survey Rept. Inv. 15.
Black, A. P.
1951 (and Brown, Eugene) Chemical character of Florida's waters:
Florida State Board Cons., Div. Water Survey and Research
Paper 6.
Brown, Eugene (see Black, A. P.)
Clapp, F. G. (see Matson, G. C.)
Cole, W. S.
1942 Stratigraphic and paleontologic studies of wells in Florida:
Florida Geol. Survey Bull. 19.
1944 Stratigraphic and paleontologic studies of wells in Florida:
Florida Geol. Survey Bull. 20.
Cooke, C. W. (also see Parker, G. C.)
1915 The age of the Ocala limestone: U. S. Geol. Survey Prof. Paper
95-I, p. 107-117.
1929 (and Mossom, Stuart) Geology of Florida: Florida Geol. Survey
20th Ann. Rept., p. 29-227.
1936 (and Mansfield, W. C.) Suwannee limestone of Florida (ab-
stract): Geol. Soc. America Proc. (1935), p. 71-72.
1945 Geology of Florida: Florida Geol. Survey Bull. 29.
1952 Sedimentary deposits of Prince Georges County, Maryland, and
the District of Columbia: Maryland Dept. Geology, Mines and
Water Resources Bull. 10.
Dall, W. H.
1892 Contributions to the Tertiary fauna of Florida, with special
reference to the Miocene silex beds of Tampa and the Pliocene
beds of the Caloosahatchee River: Wagner Free Inst. Sci. Trans.,
v. 3, pt. 2.
Davis, J. H., Jr.
1943 The natural features of southern Florida, especially the vegeta-
tion, and the Everglades: Florida Geol. Survey Bull. 25.
FLORIDA GEOLOGICAL SURVEY
DuBar, J. R.
1958 Stratigraphy and paleontology of the late Neogene strata of the
Caloosahatchee River area of southern Florida: Florida Geol.
Survey Bull. 40.
Ferguson, G. E. (see Parker, G. G.)
Hantush, M. C.
1955 (and Jacob, C. E.) Nonsteady radial flow in an infinite leaky
aquifer: Am. Geophys. Union Trans., v. 36, no. 1, p. 95-100.
1956 Analysis of data from pumping tests in a leaky aquifer: Am.
Geophys. Union Trans., v. 37, no. 6, p. 702-714.
Heilprin, Angelo
1887 Explorations on the west coast of Florida and in the Okeechobee
wilderness: Wagner Free Inst. Sci. Trans., v. 1.
Hendry, C. W., Jr.
1957 (and Lavender, J. A.) Interim report on the progress of an
inventory of artesian wells in Florida: Florida Geol. Survey
Inf. Circ. 10.
Jacob, C. E. (see Hantush, M. C.)
Johnson, L. C.
1888 The structure of Florida: Am. Jour. Sci., ser. 3, v. 36, p. 230-236.
Jordan, Louise (see Applin, E. R.)
Klein, Howard (see Schroeder, M. C.)
Lavender, J. A. (see Hendry, C. W., Jr.)
Love, S. K. (see Parker, G. G.)
MacNeil, F. S.
1944 Oligocene stratigraphy of southeastern United States: Am.
Assoc. Petroleum Geologists Bull., v. 28, no. 9, p. 1313-1354.
Mansfield, W. C. (see Cooke, C. W.)
Matson, G. C.
1909 (and Clapp, F. G.) A preliminary report on the geology of
Florida: Florida Geol. Survey 2d Ann. Rept., p. 25-173.
1913 (and Sanford, Samuel) Geology and ground waters of Florida:
U. S. Geol. Survey Water-Supply Paper 319.
Meinzer, O. E.
1923 The occurrence of ground water in the United States, with a
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489.
Mossom, Stuart (see Cooke, C. W.)
REPORT OF INVESTIGATIONS No. 37
Parker, G. G.
1944 (and Cooke, C. W.) Late Cenozoic geology of southern Florida,
with a discussion of the ground water: Florida Geol. Survey
Bull. 27.
1951 Geologic and hydrologic factors in the perennial yield of the
Biscayne aquifer: Am. Water Works Assoc. Jour., v. 43, no. 10,
p. 817-834.
1955 (and Ferguson, G. E., Love, S. K., and others) Water resources
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Supply Paper 1255.
Puri, H. S.,
1953
Contributions to the study of the Miocene of the Florida
Panhandle: Florida Geol. Survey Bull. 36.
Richards, H. G.
1945 Correlation of Atlantic Coastal Plain Cenozoic formations; a
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Sanford, Samuel (see Matson, G. C.)
Schroeder, M. C.
1954 (and Klein, Howard) Geology of the western Everglades area,
southern Florida: U. S. Geol. Survey Circ. 314.
Sellards, E. H.
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1919 Geologic section across the Everglades, Florida: Florida Geol.
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Stringfield, V. T.
1936 Artesian water in the Florida peninsula: U. S. Geol. Survey
Water-Supply Paper 773-C, p. 115-195.
Theis, C. V.
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U. S. Public Health Service
1946 Public health reports, reprint 2697.
Vernon, R. O.
1951 Geology of Citrus and Levy counties, Florida: Florida Geol Sur-
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Visher, F. N.
1952 Reconnaissance of the geology and ground-water resources of the
Pass Creek Flats area, Carbon County, Wyoming, with a section
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Wilcox, L. V.
1948 The quality of water for irrigation use: U. S. Dept. Agriculture
Tech. Bull. 962.
FLORIDA GEOLOGICAL SURVEY
WELL LOGS
Glades County
WELL 22
NWYNW% sec. 29, T. 38 S., R. 34 E.
Depth, in feet,-
Material below land surface
No samples _-- __--- 0- 65
Tamiami Formation
Marl, gray, sandy, phosphatic; fragments of echinoids
and Pecten ---__-__ 65 110
No samples --._--.__.__ ._-- .... ___ --_ .....- 110- 188
Hawthorn Formation
Clay, dark-green, plastic; mollusk fragments ----------- 188
Clay, dark-green, sandy (coarse), phosphatic; pelecypods
numerous, mostly Pecten and Area -_.---__ 188 -314
Clay, olive-drab, sandy, shelly, phosphatic ___.. --__... 314- 337
No samples ____ _______ 337 346
Clay, light-green, shelly, plastic; and olive-drab sandy,
phosphatic, shelly clay marl -__ .- -._...-- ... 346 418
Clay, dark-green, plastic; phosphorite pebbles and
mollusk fragments __ 418 465
Clay, gray, phosphatic; mollusk fragments ...--_- 465-480
Limestone, white, hard, dense, phosphatic; mollusk
fragments .__ _____ 480 505
Gravel; phosphorite pebbles, brown, up to 8 mm in
diameter; some limestone as above 505- 516
Clay, tan, plastic; many small particles of dark phos-
phorite _____ __516 537
Clay, tan, plastic; many small particles of phosphorite --. 537- 575
Clay, dark-green, quartz sand, phosphorite pebbles; some
gray sandy, phosphatic limestone ...__ __ _..._.. 575- 605
Tampa (?) Formation
Limestone, cream, hard, porous, granular, slightly phos-
phatic, and some sand ______ 605 620
Ocala Group
Limestone, cream, foraminiferal coquina, soft, porous,
chalky; Lepidocyclina ocalana __ 620 667
Limestone, cream, foraminiferal coquina, soft, porous,.
granular; Operculinoides _- 667-814
Limestone as above but fewer foraminifers __ 814- 854
Avon Park Limestone
Limestone, tan, hard, porous; numerous echinoids of
Peronella type 854-888
REPORT OF INVESTIGATIONS NO. 37
Limestone, light-tan, hard, porous, granular; Dictyoconus
cookei, Coskinolina floridana, and Peronella_ 888- 958
Limestone, tan, hard, granular, porous; some white, soft,
chalky limestone; Spirolina coryensis ..___ ---- --.-- -... 958- 1022
Limestone, tan, hard, granular; numerous Coskinolina
floridana ______. ..____...___ ----.......___.__. 1022- 1134
Lake City Limestone
Limestone, light-brown, hard, calcitic, granular,
porous; some gray dense limestone and brown porous,
finely crystalline, dolomitic limestone ...__._.__ 1134- 1215
WELL 27
NEYNW% sec. 25, T. 39 S., R. 33 E.
Depth, in feet,
Material below land surface
Pamlico Sand
Sand, gray, quartz _......_-- ..- _______ 0- 3
Fort Thompson Formation
Shell bed, marine ... ___------......--_ .._-- .._____ 3- 7
Sand, light-gray, marly ---.... --_. ---.__- __ 7- 18
Caloosahatchee Marl
Marl, dark-gray, very sandy, somewhat shelly 18- 30
Shell bed, dark-gray, sandy (shell marl) ._-------------- 30- 44
Tamiami Formation
Shell marl, light-gray, sandy --..-..-...-- _..._-- 44- 54
Marl, light-green, clayey, sandy _--..--_-_.._ .--- 54- 75
WELL 28
NW%/SE% sec. 11, T. 42 S., R. 32 E.
Depth, in feet,
Material below land surface
Recent soils
Peat __--__ --___----_____ 0 3
Pamlico Sand
Sand, gray, quartz -_- _--_ ___-__ 3- 10
Caloosahatchee Marl
Shell bed containing quartz sand and the following mol-
lusks: ___ 10- 14
Pseudomiltha anodonta (Say)
Transennella caloosana Dall
Chione cancellata (Linnaeus)
Anomalocardia caloosana (Dall)
Turritella sp.
Nassarius vibex (Say)
FLORIDA GEOLOGICAL SURVEY
Olivella mutica (Say)
Marginella sp.
Sand, gray, quartz, and shells containing the following: 14- 17
Phaeoides pensylvanicus (Linnaeus)
Laevicardium serratum (Linnaeus)
Transenella caloosana Dall
Chione cancellata (Linnaeus)
Anomalocardia caloosana (Dall)
Tellina (Merisca) dinomera Dall
Corbula caloosae Dall
Fissuridea carditella Dall
Cerithium sp. cf. C. glaphyrea litharium Dall
Turritella perattenuata Heilprin
Nassarius sp. ind.
Marginella gravida Dall?
Olivella mutica (Say)
Terebra dislocata Say
Sand, white, quartz ___ __--___ --- 17- 55
Tamiami Formation
Sand, gray, coarse, quartz, shelly .... ..----.------... 55- 63
WELL 29
SW4 SWU sec. 22, T. 40 S., R. 32 E.
Depth, in feet,
Material below land surface
Recent sand and soils
Sand, quartz __ ----- -- ------ 0- 4
Muck, peat, black 4____-.. -----_------~--- -.. ..-- 4- 8
Fort Thompson Formation
Sand, gray, quartz, marly ___8 .......--..-------.. 8- 11
Caloosahatchee Marl
Marl, gray, sandy, with a few shells ... -- ---------------- 11 15
Marl, gray -___-__-__ ---------------------- 15- 20
Marl, gray, sandy, very shelly ____......... .....--------- 20- 27
Marl, gray, sandy, slightly shelly -----___- ... .--- --- 27- 34
Tamiami Formation
Shell marl, light-gray, very sandy _...------------- 34- 38
Shell marl, light-gray, sandy 38- 42
Sand, light-gray, quartz, slightly shelly --_-__._-- 42- 48
Marl, grayish-green, sandy, shelly -___- .... 48- 56
Marl, greenish-gray, silty, plastic _.___-_-___-- 56 62
Marl, gray, sandy, very shelly 62 75
REPORT OF INVESTIGATIONS No. 37
WELL 201
NW' SW% sec. 20, T. 42 S., R. 30 E.
Depth, in feet,
Material below land surface
Lake Flirt Marl
Sand, black, quartz, carbonaceous .--.....---.. __.- __-- 0- 1
Marl, gray, fresh-water, and quartz sand --1 5
Fort Thompson Formation
Marl, tan, sandy, and hard brown fresh-water limestone 5 20
Caloosahatchee(?) Marl
Marl, tan-gray, sandy, shelly ___--_- --- 20- 38
Tamiami (?) Formation
Marl, green, sandy (medium to granule-size quartz),
slightly shelly .. .. .--......._-- ....-..__ --- __ 38- 57
Hawthorn (?) Formation
Marl, green, very sandy --..__ --..- ..- _--------__ --_ -- 57- 180
Marl, green, clayey, and some phosphorite granules and
small pebbles --... ___---- _- ..-... _-__. -- 180 220
Marl, green, sandy, phosphatic --_- -------____- ..... ____ 220- 240
Marl, white, clay, very shelly, phosphatic ------ 240- 261
Marl, white, phosphatic, interbedded with white crypto-
crystalline limestone -_ ___---___ 261 282
Marl, green, clay, phosphatic, shelly _- ____. 282- 290
Limestone, white to light-gray, finely crystalline, and
light-gray phosphatic shelly marl .-----.------ 290- 356
Marl, green, clay, shelly _--_--.----- -- -- -----356- 374
Marl, greenish-gray, and gray, finely crystalline limestone 374- 384
Limestone, finely crystalline, and some light-green marl --. 384- 400
Tampa Formation and Suwannee Limestone, undifferentiated
Limestone, white and light-tan, crystalline, porous, perme-
able, fossiliferous -____ ____-- -_.. -..._..._.. ...--400 430
Limestone, white; Robulus americanus? --__- ___-- ---. 430- 475
Limestone, white and tan, finely crystalline, and light-
gray friable fine-grained quartz sandstone --_-- -- 475 619
Limestone, tan and white, and dark-green sandy marl ---- 619- 634
Marl, olive-green, sandy ___-- ...---.---- -------- 634 642
WELL 238
NE~4SW4 sec. 19, T. 42 S., R. 30 E.
Depth, in feet,
Material below land surface
No samples ......-- __-- _-_---....- --- ---- ---- -.---- 0- 20
Caloosahatchee (?) Marl
Marl, tan-gray, very sandy .----------------- ----- .20- 30
Tamiami(?) Formation
Marl, olive-green, sandy --- -------- 30- 60
FLORIDA GEOLOGICAL SURVEY
Hawthorn Formation
Marl, green, micaceous _____ 60-110
Marl, green, clay, phosphatic 110 126
Marl, dark-green, sandy, micaceous, phosphatic, with
Bulimina gracilis and B. gracilis, var spinosus 126 -185
Marl, greenish-gray, phosphatic 185- 200
No samples 200 -226
Marl, greenish-gray, phosphatic, and crystalline lime-
stone __ 226-260
Marl, white, phosphatic, and finely crystalline limestone 260 300
Marl, grayish-green, clayey, shelly, slightly phosphatic 300- 325
Limestone, white, finely crystalline 325 390
Tampa Formation
Limestone, white, finely crystalline, and light-gray friable,
fine-grained quartz sandstone -___ 390-430
Limestone, tan, finely crystalline, and light-gray friable
medium-grained quartz sandstone ___ 430 500
WELL 240
SENW4 sec. 25, T. 42 S., R. 33 E.
Depth, in feet,
Material below land surface
No sample ___ 0- 10
Fort Thompson Formation and Caloosahatchee Marl,
undifferentiated
Sand, cream, quartz, very shelly (Chione cancellata) 10- 50
Caloosahatchee Marl and Tamiami Formation, undifferentiated
Sandstone, quartz, friable, shelly, and coarse quartz sand,
with a few small phosphate pebbles ___ 50- 90
Tamiami Formation
Marl, white, sandy, with quartz and phosphate pebbles,
and coarse friable sandstone 90- 100
Limestone, cream, sandy, silty, and coarse white shelly
sandstone 100 140
Marl, cream, silty, micaceous __ 140 160
Hawthorn Formation
Marl, sandy, silty, micaceous, and dark-green clay 160- 220
Clay, green 220 240
Marl, sandy, and green clay 240- 270
Marl, light-green, silty, and coarse quartz and phosphatic
sand; some light-green siltstone 270 350
Limestone, green, silty 350- 370
Marl, dark-green, sandy, phosphatic, shelly 370- 420
Marl, green, clayey, shelly 420- 490
Marl, light-green, phosphatic, and white phosphatic lime-
stone and green clay __ 490- 530