The construction design relies on fixed spillway elevations to be located
at the
southern ends of Ditch 1 and 2, and adjacent to the southeast corners of
Ponds 3
and 4. Ditch 1 is designed to contribute surface flow into the north section
of Pond
B. Ditch 2 is designed to combine with surface flow from Pond 3, which will
ultimately discharge into Area G. Pond 4 is designed to discharge surface
flow into
Area F. Figure 7 represents periods of time when spillover into these structures
would occur based on the proposed design elevations. The zero line represents
the
proposed spillway elevation of these structures. Each bar represents the
volume of
water available for hydration. During the Winter Storm months of February,
March,
April, and May excess water volumes were predicted to occur as spillover
from the
combined flows out of Ditch 2 and Pond 3 into Area G, and out of Pond 4 into
Area
F. The volumes of water supplied to Area G are inconsequential, since plants
are
dormant during these months. Surface water elevations fell below the designed
inverts during the critical window representing the growing season (May through
November), and during the dry season period (December through March 1994),
with
the exception of spill occurring out of Ditch 2 during September, November,
and
January 1994.
Figure 8 represents the predicted pore space volume results for the proposed
bank
site. The zero line represents the average topographic elevation of the site.
During
the first quarter of 1993, flooding conditions attributed to the Winter Storm
months
were predicted to occur for Areas E and F. Flooding events were also predicted
to
occur within Area E for the months of September 1993, and January 1994. The
remaining areas show significant declines in the water table which will require
large
volumes of water to completely fill the pore space reservoir. Model predictions
suggest resulting water table declines will produce drier soil moisture conditions,
thus promoting invasion of undesirable nuisance and exotic species during
the
growing season.
CONCLUSION
Analyses of the water balance model suggest that declining precipitation
patterns
are influencing  surface and  groundwater declines.  Evaporation  and
evapotranspiration losses from the system exceeded the gains from precipitation,
recharge, and groundwater flow. The existing cypress domes and borrow ponds
located within Area B appear to be storing greater quantities of water than
are being
recharged back into the water table. Evaporation from surface water bodies,
evapotranspiration from dense vegetation, and pond storage effects are contributing
towards the observed declines in the water table south of the TECO easement,
across the proposed bank site.


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