Lake
Jackson Photo Gallery
On September 16, 1999, much of the central portion
of Lake Jackson, a large lake on Tallahassee’s
northern side, drained down an
eight-foot-diameter sinkhole known as Porter
Hole. Sinkholes in Lake Jackson open and drain
portions of the lake approximately every 25
years. Following the September 1999 event, the FGS, in cooperation with the Northwest Florida
Water Management District, Leon County, and the
Florida State University Department of Geological
Sciences began investigating this phenomenon.
This investigation will improve our understanding
of the connection between Lake Jackson and the
Floridan aquifer system, which provides most of
the area’s drinking water.
Shallow push cores in the vicinity of Porter Hole have
been collected and are undergoing analysis, a
general map of greater Lake Jackson has been
compiled showing conditions resulting from the
natural draw down event, and the Porter Hole area
has been surveyed and mapped. Tom Scott (FGS) has
explored Porter Hole Sink with a variety of
scientists, state and local officials, and media
representatives, affording the opportunity for
down hole measurements and photography. The sink,
which occurs in a 15 feet deep depression in the
lake bed, is approximately eight feet in diameter
at its top and is about 50 feet deep, below the
average lake bed. The sink consists of a series
of convoluted passages through the limestone,
with various conduits intersecting the main sink.
The FGS has drilled four vertical core holes to
depths from 105 feet to 119 feet below the
lakebed. Interpretation and analysis of the cores
continues and will be published by the FGS upon
completion.
Lake Jackson photo gallery includes a collection
of interior and exterior images of the sinkhole
taken by Tom Scott (FGS) during the investigation of the drawdown.
