IMPORTANT FACTS ON THE
FLORIDA POWER AND LIGHT REQUEST
TO DIVERT WATER FROM THE
LITTLE MANATEE RIVER
Site. The Florida 'Power and Light Company is requesting
permission to divert water from the Little Manatee River down-
stream from U. S. Highway 301 to a cooling water reservoir
required for a proposed oil fueled 3400 MW steam electric
power generating plant. Although the Company plans initially
to construct only two 850 MW plants, for a total of 1700 MW
at this site, application is made for the maximum average
diversion rate of 60 cfs required by a 3400 MW plant. The
commitment of this maximum flow to Florida Power and Light
wil-1 enable the Company ultimately to develop this site for
the larger plant, if this should become necessary. The
attached map shows the location of the proposed plant and
Reservoir. The proposed reservoir will be created by an
earth embankment and will cover approximately 6,500 acres at
an average depth of approximately 16 feet. The reservoir's
design will provide 1-1/2 years of water storage capacity to
accommodate periods during which the flow in the river is not
sufficient to permit diversion. Approximately 500 acres of
the lake will be in Hillsborough County with the remaining
6,000 acres lying in Manatee County.
Diversion Structure. Construction at the river will
consist of an open channel approximately 1,000 feet long through
which the water diverted from the river will be conveyed to a
Pump Station. The pumping station will be a "scalping"
Type, which will divert water directly from the river without
an impoundment or dam on the river. The station will take
water from the river only when the flow exceeds the "average
minimum flow" as defined by Florida Statutes. The station
will have pumping capacity of approximately 330 cfs but will
I divert whter at this rate only when the river's flow is
sufficient. Based on the river's historical flows, the pumps
will be inoperative approximately 25 per cent of the time.
The total average flow in the river at the point of diver-
sion is 200 cfs based on the 1939 to 1971 record. The "average
*minimum flow" in the river is approximately 40 cfs or 20 per
\cent of the long term average flow. The net amount diverted
, to the reservoir, by the pumping station, will be 38 cfs or
19 per cent of the long term average flow at the diversion point.
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i The gross amount diverted from the river by the pumping station
will be 57 cfs or 28.5 per cent of the long term average flow
of the river at the .point of diversion. The difference between
the gross amount diverted (57 cfs) and the net amount diverted
(38 cfs) will be returned to the river or groundwater as seepage
and spills from the reservoir. Spills will result from rainfall
on the reservoir. The spills will return to the river by way
of Curiosity Creek.
Vegetation. The proposed reservoir will replace the
approximately 6,500 acres of existing vegetation with a fresh i
water eco-system. The most ecologically desirable plants
which will be lost are an estimated 500 acres of Oak-Cabbage
Palm woodlands located in the northern portion of the state.
Animals, Birds, Reptiles. Approximately 129 species
of, animals, birds and reptiles inhabit the 6,500 acre site.
The creation of the reservoir will force many of these
creatures to move into surrounding areas. This migration
will increase the animal density on the nearby areas and
thereby cause some loss of life due to increased competitive
pressures. The only endangered species in the site area is
the American alligator.
Weather. Generally the weather in the Tampa area is
characterized by relatively strong winds, a high mean mixing
depth, air flows which tend to be away from populous areas
during poor diffusion periods and rare instances of prolonged
air stagnation. The only adverse weather condition is a
relatively high but short duration occurrence of winds toward
areas southwest of the site, across Manatee County. The only
effect on the weather which the proposed plant might have
would be a slight increase in heavy fog in the local area.
No significant effect upon precipitation in the area is
Little Manatee River Ecology. The Florida Power and
Light Company does not anticipate that the proposed with-
drawals will increase the existing degree of salt water
intrusion into the river.
Under the diversion provisions of Florida law, the
proposed pumping will never lower the level of water in the
river below what will occur under natural annually varying
conditions and should, therefore, have no effect on fish
spawning beds that may be located in shallow areas of the
river. The intake channel itself will be constructed where
the river is relatively deep so it should not affect fish
reproduction cycles. In addition, the rate of flow of
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water to the pumping station will be sufficiently lvow thilct.
actively swimming organisms will be able to avoid entraijn:.ornt
and damage a't the pump station. Lastly, no adverse effect
on fish populations will occur due to the decreased water
volume below the facility since the species of fish found
in this geographical area can survive and reproduce equally
well in fast flowing or sluggish waters.
Regional Water Supply. Although it can be anticipated that
surface water from the Little Manatee will be used in the
future to supply fresh water to the nearby population, the
net amount diverted into the proposed reservoir will only be
19 per cent of the long term average flow of the river; and
this amount seems to be a reasonable allocation of this
resource in view of the vital role which the electric power
generated at the site will play in the life of the nearby
Groundwater. Construction of the proposed reservoir,
diversion structures and power plant is not expected to have
any significant effects on area groundwater. After construc-
tion, the quality of any water released from the cooling lake
will meet the water quality standards of the State of Florida.
Recreation Area. Florida Power and Light anticipates
that portions of the proposed reservoir may offer opportuni-
ties for recreational development by Hillsborough and Manatee
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