Piney Z- A Narrative
General Information:
Lake Piney Z is located in the middle of a chain of lakes called
collectively Lake Lafayette . Lake Piney Z is in the eastern part
of Tallahassee, Florida. It is directly below a new housing subdivision
also called Piney Z. The lake is 193 acres. In the lake there
are a number of dikes or fingers. These were built from the muck
scraped from the bottom of the lake and they will serve as fishing
dikes in the future.
Lake Piney Z has been heavily impacted by man in
the past and continues to be impacted with the newly built Piney
Z subdivision. It will also continue to be affected by man in
the future with the emergence of new subdivisions. In order to
understand the effect of man on Piney Z lake, one must first understand
the concepts of eutrophication,
Karst topography, and the Floridan Aquifer. Eutrophication is
when the plants in a water system die, then decay and settle at
the bottom of the lake. Either the decayed materials going down
a sinkhole or being washed away by the moving water naturally
clean this accumulation at the bottom of the lake. Eutrophication
can continue to accumulate if there is no moving water. It can
be accelerated by outside nutrient runoff such as fertilizer,
sewage discharge, and leaking septic systems. Eutrophication has
been a big problem for Lake Piney Z. This is mostly due to the
chemical runoff from the Piney Z subdivision, also the fact that
Lake Piney Z has been cut off from the Lake Lafayette water system
and therefore has only standing water, no movement.
Karst topography is a landscape characterized by sinkholes, streamless
valleys, and streams that disappear underground. This landscape
is created by groundwater dissolving sedimentary rock such as
limestone. This results in the formation of different landforms
such as sinkholes. Groundwater seeps into and through these landforms.
If this groundwater is polluted, then the landscape is polluted.
When talking about the Floridan Aquifer, one must
understand that the aquifer doesn’t negatively affect Lake
Piney Z but rather that the lake negatively affects the aquifer.
The Florida Aquifer is an underground system of water that purifies
the water above ground. When pesticides from human activity runoff
into the lake they pollute it. Since the Lake Lafayette water
system contains a sinkhole, this polluted water goes down the
sinkhole and directly into the aquifer.
Future of Lake Piney Z:
Lake Piney Z's best hope for recovery is the sinkhole located
in upper Lake Lafayette. Currently the land surrounding this sinkhole
is owned by the planned development Fallchase. Fallchase owns
this land because they plan to build houses on the floodplain
that is Upper Lake Lafayette. What most scientists and researchers
who are monitoring Lake Lafayette want to do is to have taxpayers
purchase the land around the sinkhole. There are no set plans
for this purchase, but hopefully something will be worked out.
Water Testing Parameters:
On our many visits out to Lake Piney Z we tested the lake in various
ways to assess the quality of the water, and its progress. We
tested the water for dissolved oxygen, pH, phosphates, nitrates,
and turbidity.
- Dissolved Oxygen:
Dissolved oxygen analysis measures the amount of gaseous oxygen
(O2) dissolved in an aqueous solution. Oxygen gets into water
by diffusion from the surrounding air, by aeration, and as a waste
product of photosynthesis. An adequate level of dissolved oxygen
is necessary for good water quality. This is so because the amount
of oxygen must be sufficient to support aquatic life. The worry
in Lake Piney Z is that due to excess eutrophication there may
not be enough oxygen left.
- pH:
pH is a measure of the acidic or basic (alkaline) nature of a
solution. The concentration of the hydrogen ion [H+] activity
in a solution determines the pH. PH is a very important factor
to consider in maintaining the water quality of a lake. Runoff
from agricultural, domestic, and industrial areas may contain
iron, aluminum, ammonia, mercury or other elements. The pH of
the water will determine the toxic effects, if any, of these substances.
We tested for it every time. Luckily Lake Piney Z has a very good
level of pH and consistently ranges from 5 to 6. Therefore any
runoff Lake Piney Z encounters has yet to effect the pH.
-Nitrates:
Nitrates are a form of the very abundant element Nitrogen. Nitrogen-containing
compounds act as nutrients in streams and rivers. Nitrate reactions
[NO3-] in fresh water can cause oxygen depletion. If the oxygen
is depleted then the organisms, such as fish, may die. Nitrogen
mainly enters bodies of water through industrial and municipal
wastewater, septic tanks, or animal wastes. Bacteria in water
quickly convert nitrites [NO2-] to nitrates [NO3-]. This can be
potentially detrimental to the fish.
Phosphates:
Phosphates are one of the leading causes of eutrophication. Rainfall
can cause varying amounts of phosphates to wash from farm soils
into nearby waterways. Phosphate will stimulate the growth of
plankton and aquatic plants. If an excess of phosphate enters
the waterway, algae and aquatic plants will grow wildly, choke
up the waterway and use up large amounts of oxygen. The rapid
growth of aquatic vegetation can cause the death and decay of
vegetation and aquatic life because of the decrease in dissolved
oxygen levels.
Turbidity:
Turbidity is basically defined as the clearness of water. If there
is too much unclearness then the particles causing it result in
a scattering of light. If the light is too scattered then it is
unable to reach the plants. This stunts the growth of plants,
which sometimes provides food for fish. It also inhibits photosynthesis,
which creates most of the dissolved oxygen. Obviously light is
very important to the quality of aquatic life. Turbidity is an
important factor to monitor.
