Hydrogeology and Groundwater Quality of Highlands ... - USGS

24 Hydrogeology and Groundwater Quality of Highlands County, Florida
27°30’
27°15’
27°00’
HARDEE
COUNTY
DESOTO
COUNTY
CHARLOTTE
COUNTY
Figure 18. Generalized thickness of the surficial aquifer.
are common, but can exceed 50 ft below land surface along
some parts of the Lake Wales Ridge in Highlands County.
In the low-lying, poorly drained areas, the water table generally
is at or within a few feet of the land surface.
The altitude of the water table fluctuates in response to
the net rate at which water in the surficial aquifer is recharged
or discharged. The principal factors controlling the rate
and magnitude of fluctuations in water levels are related to
changes in precipitation, evapotranspiration, and local and
regional pumping from the surficial aquifer, and to a lesser
degree, groundwater withdrawals from the intermediate and
Floridan aquifer systems. Groundwater levels in the surficial
aquifer fluctuate seasonally and generally reach an annual
250
200
81°30’ 81°15’
81°00’
100
50
Avon
Park
100
50
200
Sebring
POLK
COUNTY
Kuhlman
200
HIGHLANDS
COUNTY
Lake
Placid
300
250
Base modified from U.S. Geological Survey digital data, 1:100,000, 1985
Albers NAD projection 1983
0
0
100
Hicoria
Venus
Lake
Istokpoga
Lorida
50
Archbold
Biological
Station
ROMP 14
5 10MILES
5 10KILOMETERS
Kissimmee
100
River
Brighton
50
Cornwell
100
OKEECHOBEE
COUNTY
GLADES
COUNTY
OSCEOLA
COUNTY
EXPLANATION
LINE OF EQUAL THICKNESS–Shows
thickness of surficial aquifer. Dashed
where approximate. Contour intervals
are variable, in feet.
WELL CONTROL POINT
maximum in September or October (near the end of the wet
season) and decline to a minimum in April or May (near the
end of the dry season). Spring water levels usually are lower
than fall water levels because only about 30 percent of the
total yearly rainfall occurs from November through April.
Seasonal recharge by infiltration of precipitation causes water
levels to rise in the summer months when rainfall totals are
normal or above normal. Drier climatic conditions cause
water levels to decline within a relatively short period of time
following seasonal-high water levels in the summer. Although
the magnitude of the water-level fluctuation in wells varies
across the county, hydrographs show seasonal fluctuations of
water levels ranging from about 1 to 5 ft (fig. 20).