Title: Highlights of Water Management in the Southwest Florida Water Management District
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Title: Highlights of Water Management in the Southwest Florida Water Management District
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Language: English
Publisher: Ground Water
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Spatial Coverage: North America -- United States of America -- Florida
 Notes
Abstract: Highlights of Water Management in the Southwest Florida Water Management District, May-June 1973, Vol 11, No. 3
General Note: Box 10, Folder 12 ( SF Water Rights-Water Crop - 1973, 1976-77 ), Item 2
Funding: Digitized by the Legal Technology Institute in the Levin College of Law at the University of Florida.
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Bibliographic ID: WL00002238
Volume ID: VID00001
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Full Text
JiLUL_


Highlights of Water Management in the

Southwest Florida Water Management District

by Garald G. Parker, C.P.G.


Reprinted from the May-June 1973, Volume 11, Number 3 issue of Ground Water


1 _








Highlights of Water Management in the

Southwest Florida Water Management District


by Garald U. Parker, C.P.G.a


*..


ABSTRACT
The District, comprising 15 counties and nearly
10,000 square miles in central western Florida centering on
the Tampa-St. Petersburg metropolitan area, is one of the
nation's most rapidly growing areas. Water-budget analyses
compared with expected water demands for water by the
burgeoning population indicate that by about 1985, if the
present population growth rates and water-use demands
persist, we will be using as much water as nature supplies us
with on the long-term average annual basis, for once-only
uses. After that, to supply the water needed, we will either
"mine" water on a District-wide scale or bring about other
remedies. Among these are, without attempting to list
them in order of priorities:
1. Reuse water again and again by cleaning it up and
recharging the aquifers with both high-grade sewage effluent
either by land-spreading or by injection through recharge
wells into the aquifers.
2. Engage in desalination of the almost limitless
quantities of brackish ground water, especially in the coastal
areas where salt-water encroachment is occurring on a large
scale.
3. Induce aquifer recharge by creating storage space
in the aquifers in areas that are currently full to overflowing.
In such areas precipitation is now largely rejected as re-
charge and ground-water seepage is lost to evapotrans-
piration.
4. Effect economies of water use by both industry
and agriculture-by far the largest users of water in our
District-by regulation of amounts that may be used for
irrigation and for various other industrial and agricultural
processes.
5. Divert flood waters from direct runoff to the
oceans to temporary flood detention areas from which
water can be drawn off to aquifer recharge facilities.
6. By permit processes regulate the amounts of water
that can be withdrawn for any purpose from either ground-
or surface-water sources in the District thus preventing
overdraft and resultant lowered water levels and, in some
areas additional salt-water encroachment.
7. Eliminate waste of water, particularly the existing
large losses from thousands of existing wild-flowing artesian
wells.


aChief lydrologist and Senior Scientist, Southwest
Florida Water Management District, Brooksville, Florida
33512.
Discussion open until October 1, 1973.


8. Develop new, large well fields upgradient from the
large coastal springs that now are discharging along our
Gulf Coast, a total of about 900 mgd, none of which is now
Used for water supply.
9. Space new well fields for regional water-supply
purposes widely over the District and arrange for organiza-
tion of regional water-disti ibution and use systems.
10. As soon as feasible engage in rainmaking to
augment nature's normal precipitation.
Under nature's irrigation supply-demand pattern and
man's previously unmanaged and all-too-often wasteful
usage growing beyond all previous expectations, the water
supply and the flood-and-drought situation have become
impossible to live with. But with proper management of our
water and land resources the tide can be changed, and it
will be possible to live comfortably within our available
resources. It will cost us more but the increased cost is the
price we must pay to live in an area where demands on the
water resources are rapidly outgrowing nature's provisions.

The Southwest Florida Water Management
District comprises an area of nearly 10,000 square
miles and 15 counties situated in central-western
Florida (Figure 1). In fact, the District is almost as
large as the State of Maryland and is larger than any
of the following States: Connecticut, Delaware,
New Hampshire, New Jersey, Massachusetts, Rhode
Island or Vermont.
"Big" government is loathed in Florida just as
it is generally elsewhere in the United States, and it
took a nearly catastrophic set of weather circum-
stances in 1959 and 1960 to convince citizens of
this region that local government is too small, too
weak and generally too provincial in outlook to
prevent or alleviate such destructive floods as those
that plagued this region in March 1959, and again in
March and September 1960.
As a matter of fact, this region has experienced
alternating flood and drought throughout both
geologic and recorded history. But as long as the
population was sparse and the demands for water
supply were inconsequential, the people could
tolerate the vagaries of nature. For example, the
great flood of September 1933 might have been
even more disastrous than those of 1959 and 1960,




,,il [ 1 i I I1,


Fig. 1. Index map showing the location of the Southwest
Florida Water Management District.


but in 1933 the population was small and homes
and business establishments generally were not
built in flood prone areas. Today the population is
large, expanding rapidly, and much of it is develop-
ing in hazardous, flood prone areas. The counties of
Florida have the authority to enact flood plain
zoning regulations but, with rare exceptions, have
failed to do so.
Historically, this area has experienced.numer-
ous droughts of 1 or 1- to 2-years' duration but
people had always been able "to make out" because
their small needs for water could be met by nearby
sources. Now we are experiencing, generally over
the entire District, a drought of unprecedented
proportions with 10 years of subnormal precipita-
tion out of the last 12, and with an accumulated
rainfall deficiency of about 100 inches or more
(Figure 2). With a long-term average annual pre-
cipitation for the District of about 55 inches, the
deficiency is almost that of 2 years of expected
rainfall. Such conditions of extrenic drought and
flood, complicated by an exploding population
with a vast thirst for water, have created water-
supply and flood protection problems of such large
magnitudes that local governments-village, city
( and county-cannot successfully combat them.
Accordingly "Big Government" in the form of
a regional flood control agency was demanded by
local citizens in 1960. The State Legislature re-


_~


Deportur. From Normal Rainfall For Tompa, Fla.
55AO Ok us WEAMNCR SuaEAU IaECOaOS





O 10 a I515
0 ON PBIROO OF



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.VVLA.T1'! ATURE_
so 4~ E, R .AEC .o- -- 20 3
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Fig. 2. Graph of departure of rainfall for Tampa, Florida.
5. 1-4 301) q ?boor
al an



1 a .el .* a u .a a . .: '

Fig. 2. Graph of departure of rainfall for Tampa, Florida.


Fig. 2. Graph of departure of rainfall for Tampa, Florida.


sponded by enacting Chapter 61-691, Florida
Statutes, which established the Southwest Florida
Water Mafagement District. The Act became law
on July 1, 1961. Its Section 1 states:

"For the purpose defined in Chapter 378, Florida
Statutes, and to facilitate the creation and initial operation
of a district under said Chapter, Southwest Florida Water
Management District is hereby created a public corporation
for carrying out and effectuating the provisions of said
Chapter. Other than as herein provided, Southwest Florida
Water Management District shall operate under and be
governed by the provisions of Chapter 378, Florida Statutes,
as amended from time to time."
Chapter 378, Florida Statutes, is known as the
Flood Control Act. It prescribes rules and regula-
tions governing the establishment of flood control
and water management districts. Among other
things this Act provides for cooperation with
agencies of the federal government to effect flood
control management (378.01) and establishes a
water resources development account (378.03) in
the general revenue fund of the State which is to
provide financial assistance to districts established
under its authority, including the funds as grants-
in-aid to purchase lands required for such purposes
as water storage areas, canal or reservoir sites and
bridges.
The members of the Board of Governors, as




LI-_-_ILLIIIL _L__LL4


provided in Chapter 61-691, were appointed by the
Governor and met for their organizational meeting
on August 28, 1961, at the Capitol in Tallahassee,
Florida. By March 6, 1962, the entire District was
organized into 11 River Basins (Figure 3), each
with its own Basin Board operating at the grass-
roots level to levy taxes, build and operate flood
control and other water management structures
within limits of their river basin boundaries, and to
be responsible for carrying out the provisions of
Chapter 61-691 within their respective boundaries.
Each Basin Board, however, is responsible for its
actions to the 9-member Board of Governors of the
District.
In the meantime, members of the Florida
delegation to the U.S. Congress were busy arranging
through the Committees on Public Works in both
the House and the Senate for aid of the U.S.
government under the provisions of both the River
and Harbor and Flood Control Acts. This resulted
in the establishment of the Four River Basins,
Florida, Project as described in House Document
No. 585, 87th Congress, 2nd Session, 1962 (Figure
4).
Under this authority and with funds provided
by the U.S. Congress, the State of Florida's water
resources development account and local ad valo-
Srem taxes, the U.S. Army Corps of Engineers and
the Southwest Florida Water Management District
began work on the Four River Basins' Project on
October 23, 1962.
The District staff at that time consisted of
Only 3 persons, but additional personnel were added
as work progressed on the flood control aspects of
the Four River Basins' Project. Early in the Project
emphasis was placed on starting construction of the
Tampa Bypass Canal with its system of channels
and water control structures designed to route
damaging floods around the periphery of Tampa
instead of through it; on developing the outdoor
recreation plan to allow and provide for citizen use
of flood control properties and other works of the
District such as reservoirs and flood detention areas
for such activities as hunting, fishing and camping;
beginning work on the Lake Tarpon project to
prevent flooding and to seal off salt water from
access to the lake, thus allowing it eventually to
become a fresh-water lake; to acquire lands within
the 850 square miles of the Green Swamp for flood
detention purposes and, hopefully, either for direct
aquifer recharge or for later downstream release as
water supplies to the rapidly growing coastal urban
areas; to improve navigation and water conservation
on the Withlacoochec River by construction at the


Fig. 3. Map of Southwest Florida Water Management Dis-
trict showing the 11 river basins which comprise the
District.


Fig. 4. Map of Southwest Florida Water Management Dis-
trict showing works of the Four River Basins' Project of
the U.S. Army Corps of Engineers and the Southwest
Florida Water Management District.


*.






0
Wysong Locks and Dam of the inflatable "Fabri-
dam"; on the purchase of a huge flood detention
area in the lower Hillsborough River to serve also
Sas a site for a big, new well field to serve the
increasing needs of the City of Tampa; on the
replacement of an antiquated and worn-out dam on
the Oklawaha at Moss Bluff with a bigger, new
locks and dam;on the construction of the Masaryk-
Stown Bypass Canal to prevent a recurrence of some
of the worst flooding experienced in the District
during the 1960 floods; on the construction of the
Jumper Creek Flood Detention Area and'the Tsala
Apopka Outfall Canal on the Withlacoochee River
in Citrus County; and on numerous other projects
such as the Big Cypress Creek Flood Detention
Area including a regional well field.\
Works such as these, including the building
and occupancy of a new headquarters office and
service center on a beautiful oak and pine forested
site 7 miles south of Brooksvillc (Figure 1) occupied
the chief attention of the staff until early 1969.
At that time, owing to growing pressure on
the District's Governing Board to regulate the drill-
'ing of wells and the uncontrolled development of
ground water, the decision was made to establish a
Ground-Wazcr Hydrology Division for these pur-
poses. This was done in March 1969, but was
( quickly reoriented to a Hydrologic Division when
.'it became understood by the administrative and
executive officers of the District that ground water
and surface water in this District are only different
sides of the same hydrologic coin and must be
managed as a single resource.
Upon the activation of the new Hydrologic
Division, the nucleus was available for the estab-
lishment, under Chapter 373.142, Florida Statutes,
of a Water Regulatory District. This was accom-
plished in July 1969, with the new organization
having the same Board of Governors and the same
District boundaries as the original District. The
staff wrote the di-aft of a proposed regulatory law
and on October 1, 1969, Chapter 357R-1, Florida
Administrative Code, "Orders of the Southwest
.Florida Water Management District (Regulatory)"
became effective. Chapter 357R-1 defined the rules
and regulations for the development, use, control,
and conservation of water and related land re-
sources, with particular reference to ground-water
resources in the District. Its several sections pro-
vided for: (1) Purposes and definitions; (2) Regis-
Stration of well drillers; (3) Construction of wells;
S(4) Inventory of wells and water uses; (5) Civil
action for damages; and (6) Penal provisions.
Under these regulations the registration of all


well drillers and engineering laboratories drilling
holes of 2 inches in diameter or larger was begun
on January. 1, 1970; all drillers of good repute and
adequate experience were "grandfathered" in dur-
ing this first year but any not registered by January
1, 1971, were required to take both a written test
in the office and a demonstration test of drilling
skills using their own rigs'"on the job."
In the office, IBM card systems were set up
for data control, filing, retrieving and processing.
Before many months had passed the staff was
processing an average of nearly 1,000 well permits
and well completion reports each month and to
date have registered 297 well drilling contractors
and 1,107 drillers. A total of 22,939 well drilling
permits have been processed from January 1, 1970
to December 1, 1972.
Owing to unforeseen weaknesses and incom-
plete coverage of our initial rules and regulations
(357R-1), revisions were made and adopted as
Chapter 16CC, Florida Administrative Code, effec-
tive February 3, 1972. Later, on July 1, 1972, the
Hydrologic Division was given broader functions
and entitled the Water Resources Division; simul-
taneously the biologists of the Environmental
Team, previously a unit loosely attached to the
Office of the Executive Director, were made the
nucleus of our newly established Environmental
Department. This rearrangement allows for better
use of personnel, equipment and facilities, and the
organization as needed from time to time of ad hoc
teams of hydrologists, geologists, biologists and
engineers to attack practically any problem of
environmental, water resources, or engineering con-
cern. Currently, a Planning Division is being estab-
lished. Other Divisions, whose titles suggest their
areas of responsibility are: Administrative, Legal
and Office of the Senior Scientist-Chief Hydrol-
ogist, Engineering, Environmental, Field Opera-
tions, Finance and Accounting, Real Estate, Tech-
nical Services and Water Resources.
Although the Four River Basins' Project is still
the largest in terms of money and manpower ex-
pended on District programs, the problems relating
to water supply have taken over the major emphasis
of our present planning. Scarcely a day passes-if
ever-that water or water-related problems some-
where in the District do not make newspaper, TV
and radio headlines. Or saying it another way,
water and water-related problems are always in the
news and by far the most of these relate to water
supply.
In order to find solutions to these water prob-
lems and to manage water adequately, it is neces-


I _


A ll 1 .. I..,1 1. 1,




. 1 1 tll I II ,


sary that we understand the nare and occurrence
of our water resources. Basic to this understanding
is the determination of bow much of what kind of
water is where and how it varies in quantity and
quality, both in space and in time. To gain this
essential knowledge we rely heavily upon a compre-
hensive, cooperative arrangement with the U.S.
Geological Survey to develop.both the systematic
and special basic data needed for management
purposes. This is supplemented by generalized
geologic and hydrologic studies df Florida by the
Florida Department of Natural Resources in co-
operation with the U.S. Geological Survey and the
Southwest Florida Water Management District. The
information supplied as a result of these coopera-
tive agreements covers such areas as: (1) flows and
stages of streams; (2) flows and stages of ground
water; (3) study and description of both the
chemical and biologic quality of ground and surface
waters; (4) investigation and description of lakes,
aquifers and aquicludes; (5) preparation of water
table and potentiometric maps for various places at
different times of the year; (6) evaluation and
description of the water resources of areas of
particular interest, such as for example, the Green
Swamp, the Gulf Coastal zone of salt-water en-
croachment, the "world's biggest orange grove," an
area of 62 square miles in DeSoto County, and the
phosphate-mining district in the upper Peace and
Alafia River basins; and (7) others such as one or
more contiguous counties not previously studied in
detail. Topical cooperative studies include such
subjects as: (1) deep well disposal of waste waters;
(2) the effects of spray irrigation disposal of sewage
effluent; (3) the artificial recharge of aquifers;
(4) salt-water encroachment; (5) the development
of aquifer and river basin digital models; (6) ground-
water-surface-water relationships; and (7) forecast-
ing the formation of sinkholes. This is far from
being a complete list of areas and topics of study
but is fairly representative of the scope of our
cooperative program with the U.S. Geological Sur-
vey. This cooperative arrangement, covering fiscal
years 1963 through 1972, has amounted to a total
of $4,220,300 of which the District has contributed
one half and the Survey the other half. The pro-
gram has steadily grown from its inception and is
now funded (1973 FY) at $607,000 (both sides
included), but it is still inadequate to cover our
needs of data for water management purposes.
To supplement the U.S. Geological Survey
cooperative program, special studies are contracted
with consulting firms of engineers, hydrologists and
environmentalist; and basic to all our field studies


is a program of i ping the District, piece by piece
as funds become available, by photogrammetric
methods. Most mapping is done on a scale of 1 inch
equals 200 feet and with. 1-foot contour intervals.
This mapping is done by contract with firms
specializing in photogrammetry.
In addition to the work done and data
assembled by the U.S. Geological Survey, the
consultants and the photogrammetric firms, the
District staff of 24 water resources professionals
and 9 subprofessionals gathers a vast amount of
field information both personally and from the
well completion reports required by law to be
completed and sent in by the well drillers operating
within the District. Such data are filed, stored and
later retrieved as needed by use of IBM computer
facilities supplemented with standard filing and
storage systems. Special studies of all available
data are combined to make management decisions
on all levels ranging from the regulation of pump-
ing- regimes and quantities of water pumped from
existing wells and well fields to the granting or
denial of a permit for a new well, the plugging and
abandonment of an old one, the taking of water
from any surface-water source, or the dredging,
filling or building of structures in canals or streams
of the District. Likewise, decisions are made re-
garding whether or not a proposed new well field
may be developed and if so-how, where, and when.
Conditions of its drilling, completion and subse-
quent operation are carefully regulated to avoid
overdevelopment of the resource or damage either
to the environment or to existing water-supply
developments.
Additionally, operations of existing well fields
and all other large sources of withdrawal are being
strictly monitored and controlled. This has already
led to orders for the reduction of pumping from
existing well fields of the City of St. Petersburg, of
the County of Pinellas, and specific wells of the
phosphate industry. Orders for reduction of exist-
ing large scale, pumping related to excessive or
inefficient use of industrial and agricultural waters
are now being finalized. Currently our knowledge
of water use and withdrawals largely depends upon
unverified reports from the operators. The new
orders will require the metering of all water from
large capacity wells or other sources, and quarterly
reporting by the operators of their withdrawals and
final disposition of the withdrawn waters. Thus, for
the first time in any large area of Florida, total
measured withdrawals and total consumptive uses
will be .known. Such information is essential for
proper management and eventual allocation of


I


3


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water resources for whatever uses man needs to
make of them.
C Environmental assessment of proposed land
developments, drainage proposals, eutrophication
control schemes for lakes and reservoirs, and many
other similar or related studies are a regular part of
our activities. The staffers making these studies and
management decisions, some of which are in the
form of recommendations for action either to the
District Governing Board or any of th'e 11 District
Basin Boards, consist (as of 12-1-72) of 3 biologists,
11 engineers, 3 geologists, 4 hydrologists, 3 hydro-
geologists, and 9 hydrotechnicians.
The staff also engages in a wide variety of
"people-service" functions. These include such
matters as:
1. Preparation and publication of The Hydro-
scope, the monthly journal printed to keep the
public informed not only of current important
happenings affecting the water resources of the
District but enlightening our nonprofessional read-
ers on interesting or current technical matters (Vol.
1,No. 1 was issued in January 1970). Recent topics
have included articles on salt-water encroachment,
how to interpret and utilize potentiomctric maps,
the meaning and value of hydrographs, the nature
of our water-supply problems and how to use the
water budget approach to determine the adequacy
of our water resources for future population
growth, the size and location of new well fields,
and many others.
2. Participation in meetings of learned and
scientific societies, engineering and professional
associations, public forums, seminars and the giving
of talks or speeches before Boards of County Com-
missioners, City Councils, scholastic groups ranging
from university level to the elementary school, and
active membership in citizen-sponsored a c tion
groups seeking such objectives as new and improved
water treatment and/or sewage treatment plants, or
the end to a drainage scheme or one of land
development that could be damaging to the water
resources or to the environment.
3. Planning for the acquisition of new flood
water detention areas and/or new well fields that
would be integral parts of a regional water-supply
system for selected parts of our urbanizing areas
and their conjunctive use for citizen enjoyment,
S( including camping, fishing, hunting, bird-lore,
school "Outdoor Classrooms," nature trails, canoe-
ing courses, and others.
Now at this point, it may be well to describe


the nature of some of the water-supply problems
we are working on and some of the solutions to
thee problems that are either proposed or have
been determined.
The number one problem relates to how much
water is available for water-supply purposes and
how much water can be withdrawn from what
sources for consumptive use. Currently we can only
derive "ball-park"' values, because, with the" kinds
of basic data available to work with, this is the
best that can be done at the present time.
To quantify the water-supply situation we
make use of the water budget method. However,
we must use the results we obtain with caution,
recognizing that they are only "ball-park" values
because all the factors we plug into our equations
are themselves only approximations. Precipitation,
for example, is measured at widely scattered
stations over the District and most of the records
are short, in the order of 10 years. or less; few
exceed 50 years. Thus, precipitation values are not
nearly as good as needed. The long-term average
rainfall over the District appears to be about 55
inches per year.
Runoff, the discharge measured in surface
streams, is perhaps even less well defined than
precipitation. Runoff records are shorter, few
exceeding 40 years; and, to avoid tidal conditions
in the estuarial sections of our coastal streams,
gaging stations are generally several miles or more
inland from the stream mouths. Thus the runoff
increment in the stretch between the gaging station
and the stream mouth is unmeasured and must be
estimated. Total, long-term average runoff the
District over, is apparently about 15 inches per
year.
Ground-water discharge into the lower, tidal
portions of the streams and into the Gulf of Mexico
via shore zone seeps and submarine springs cannot
be measured directly so must be determined in-
directly. Likewise, storage and flow of ground
water in the aquifers cannot be measured directly
as is streamflow; therefore, such information must
.be derived indirectly from study of pumping test
data that give us approximate values of the co-
efficients of transmissibility, storage, and leakance,
and from potentiometric and water table maps that
provide us with gradients and lengths of flow sec-
tions through the saturated thickness of the
aquifers.
Adding to our quantification problem is the
fact that there is no direct way of measuring evapo-
transpiratioin losses. Generally, evapotranspiration
(Et) values are derived as a residual by subtracting


,r...
L




.l. L l .L, 1


runoff (R) from precipitation all in inches of
Water. This is more reliable the longer the period of
record and should be at least a year long. By
starting and stopping each water budget period at
the same time of.year the annual cycle of wet and
dry periods will be complete, and no accounting
may therefore have to be made of changes in
storage in ground- or surface-water bodies, or in the
soil moisture above the water table. If significant
changes in storage have occurred, these then must
be plugged into the right-hand side of the equation.
Runoff is essentially the measure of the total
potential water crop, but it is only a potential, not
an actual measure of what can be taken for con-
sumptive use. Some water must be left to maintain
the flow in the streams and to prevent lakes,
swamps and marshes from drying out. For once-
only use, as is the common current practice here in
the Southwest Florida Water Management District,
it appears that we'd be lucky indeed if we could
capture and use more than / R. How much would
this be, and how many people would it supply with
the amount of water they will need?
First, let's calculate the yield possible to ob-
tain from the 15 inches of R. One inch of R from
one square mile for one year is approximately 17.4
million gallons. /3 X 15" = 5", the expected water
crop, and 5" X 17.4 mgy/mi2 = 87 mil. gal/mi2/yr.
From 10,000 sq. mi. the "ball-park" value of the
water crop would be 870 billion gallons, or 0.87
tgy (trillion gallons per year).
Current District water use data are still in the
process of being computed and in the absence of
actual values, we shall estimate that the usage is
about 1,000 gpcd (gallons per capital per day). This
compares with U.S. Geological Survey figures for
the 1970 national use at 1,800 gpcd. Our rate of
use here is lower than the national use inasmuch as
we have fewer heavy industries and smaller agricul-
tural uses in the District than in the industrial East
and the irrigated West. Nonetheless, our huge
phosphate and citrus industries are very large users
of water and run the gpcd figures up from around
175-250 gpcd for our larger cities, and 100 gpcd
for village uses, to this higher estimated District-
Swide value.
The population of the District is now about
1.75 million people and it is generally forecast by
demographers that this will double by about 1985.
Given 1.75 million persons and 1,000 gpcd once-
only usages, our current water demand is about
365,000 gpcy (gallons per capital per year). This
totals 638.75 bgy (billion gallons per year) or 0.64
tgy (rounded).


With an c atcd available average annual
water crop of 0.87 tgy and a water use of 0.64
tgy, we currently have a surplus of 0.23 tgy, or
enough water for a population increase of about
630,000 persons. Thus, on the basis of these
estimations, we will be using all of the available
water crop before 1985 and water mining will
begin on a large, increased scale unless ways are
found either to augment the water crop or decrease
usage, or both.
So we have cause for concern, but not for
alarm. Even if before 1985 we use all the annual
water crop, we will not be running out of fresh
water. The great Floridan Aquifer (our huge "water
barrel") underlies the State everywhere and here
ranges in thickness from about a thousand feet to
more than 2000 feet. Totally, under the nearly
10,000 square miles of the District, the Floridan
Aquifer stores far more fresh water than is stored
in all of the Great Lakes combined.
-However, there is a limit to the amount that
we may "mine" from this great aquifer, for much
of its fresh water is in dead storage, a dead storage
imposed by the Ghybcn-Ilerzbcrg principle of salt
water-fresh water relationships. The Floridan pen-
insula is surrounded by ocean water and every-
where, at some depth, it is underlain by salt water
some of which is more than 3 times as salty as the-
ocean.
So, except for relatively short periods of time,
we dare not draw the regional water level down to
or below sea level. Thus we can only safely use
that part of this huge lens of fresh water that is
above sea level and this is a comparatively small
part of the total volume in storage. If we were to
manage our ground-water withdrawals so poorly as
to deplete the top storage (the part above sea level),
the bottom storage (the part below sea level) will
slowly shrink in direct proportion to top-storage
depletion and as a consequence salt water would
move both inland from the Gulf and upward from
below. Once this happens it would be practically
impossible to get the salt water pushed back out.
-However, even salt-water encroachment is not
all bad, for it furnishes us with an abundant supply
of brackish water that can be sweetened for water-
supply purposes. Recent breakthroughs in the
reverse osmosis (RO) method have apparently made
this method competitive with development and
transport of fresh-water supplies via pipelines from
distant well fields. The newest, and probably the
most efficient desalination plant in the U.S., is th'l
500.000 gpd RO plant at Rotunda West on Char-
lotte County's Placida Peninsula, about 20 miles




- lL~ IL JL.I ,I
. & a -


west of Punta Gorda. This hew plant was installed
in 1972 at-a cost of $385,000, including pumps,
wells and treatment plant. Rotunda plans to expand
this plant to 2 mgd in the near future. Cost of
treating brackish water from wells at the site and
reducing the 7,000 ppm chloride in the untreated
well water to less than- 250 ppm with only one
pass through the exchange medium is expected to
be about 50 cents per thousand gallons. Rotunda's
-engineers calculate that such water can be profit-
: ably delivered to their consumers at 85 'cents per
thousand gallons. The salty waste water produced
is piped to the nearby Gulf of Mexico where it is
swept away by the tides to mingle harmlessly with
the vast salty waters of the Gulf. \
In summary, water management controls are
needed to prevent this region and our District from
becoming hydrologically bankrupt. It appears that
by about 1985 we will be using all of the average
annual water crop and, as a consequence, unless
action is taken in time to forestall it, we will be
mining water on an increasing scale. Water is
already. being mined on a large scale in the phos-
phate field of the upper Peace River basin where
the potentiomctric surface of the artesian water in
the Floridan Aquifer has dropped 20 to 60 feet
over an area in excess of 1,000 square miles during
- the. last 20 years. Some of the preventative and
conservation measures we may employ include:


A. Reduce R (runoff) losses to the Atlantic Ocean
and the Gulf of Mexico.
1. Establish and utilize additional flood reten-
tion reservoirs.
2. Create recharge facilities in association with
such reservoirs to hurry flood waters into
aquifer storage.
3. Establish salt-water control dams on tidal
canals and. streams and place these dams as
near the shoreline as feasible. Hold a fresh-
water head behind each dam at least 21 feet.
above mean sea level and higher if possible.
These water control structures will not only
prevent bleeding off of fresh water, but will
prevent salt-water encroachment both in the
dammed-off section of the canals and streams
and also in the aquifer at depths directly
related to the height to which the fresh-water.
head can be held above msl (mean sea level).
This is in accordance with the Ghyben-
Herzberg principle which states that, for each
foot of fresh-water head above msl, the under-
lying salt water is depressed about 40 feet.


B. Reduce Et evapotranspirationn) losses.
1. Evapotranspiration loss reductions can best
be accomplished by lowering the water table
in swampy and marshy places below the reach
of water wasting plants. Choices of areas and
plants that must be preserved and protected
against greatly lowered water levels will have
to be made in order to decide what areas can
be utilized and what ones cannot. Some areas
must be saved from lowering the water level
in order to preserve natural forest and swamp
environments for esthetic purposes as well as
for wildlife sanctuaries and human enjoyment.


C. Reduce waste of water.
1. Increase charges for water, particularly for
the large users, who now, for the most part,
pay for their water at a rate which declines as
the water used increases. Possibly water sever-
ance taxes should be utilized for large, non-
public users, so as to obtain the joint benefits
'of augmenting District income (needed to pay
for increased costs of water supply and man-
agement) and causing water users to be con-
cerned with wasting. The more costly the
water, the less the users are likely to waste it.
2. Require reuse of water for those municipal,
commercial, industrial and agricultural efflu-
ents that are practicably reusable. Once
through the mill and then discharge to the
ocean is a wasteful luxury that no longer can
be tolerated.
3. Many irrigators now put far too much water
on their crops. Irrigators should be educated
to use only as much water as is actually
required. Some advantageous economies could
be effected by using, whenever possible, high-
grade sewage effluent, including its load of
nutrients (N, P and C) instead of pumping
.additional raw water from wells. Use of such
enriched water would save the farmer, or
rancher or golf course irrigator from having to
apply artificial fertilizers and thus save him
money while at the same time reducing nutri-
ent runoff to the streams. A gallon of such
water used in this manner saves an additional
gallon from being pumped from the aquifer
thus extending our water crop.
4. Numerous abandoned artesian wells are now .
flowing to waste, depicting the aquifers and
causing salt-water encroachment in the coastal
areas and lowered water levels inland. Each of
these wells should be plugged securely from


L.







bottom to top to effectively stop this senseless
waste of water.

D. Augment present supplies.
1. Reuse of. water (C-2 and C-3 above) is a
means of augmenting current supplies.
2. Preventing salt-water encroachment is an aug-
mentation of existing supplies.
3. Recycling cleaned-up sewage wastes is one of
our biggest sources of "new" water. Most
municipal sewage is 99% reusable water. Being
run through "tertiary" (extended secondary)
treatment to reduce impurities of all kinds and
result in a product that is at least as good as
water naturally available in the aquifers and
streams of the area, would make such water
available for human reuse after being artifi-
cially recharged to our aquifers or mixed with
streamflow. Just one reuse of a year's water
crop would allow the water crop to go twice
.as far. Or, saying it another way, it would
serve twice as many people. This can be done,
but at a cost. It is a cost that, eventually, we
must pay. The question isn't if we should do
it, the question is only when and how shall we
do it?
4. Capture as much flood flow as we can and
Inject it into the only available large storage
reservoir-the Floridan Aquifer. This can be
accomplished best by developing flood de-
tention reservoirs with discharge works lead-
ing to those parts of the District where large
drawdowns of water level have created billions
or trillions of gallons of available storage
volume. Some such large storage capacity
exists in the areas of pumping influence that
surround every large well field in the District,
but the largest potential storage is in the areas
of large drawdown around the phosphate and
citrus production areas, mostly in Polk, eastern
Hillsborough and eastern Manatee Counties
where, over more than a thousand square
miles, water levels in the Floridan Aquifer
have declined 20 to 60 feet or more in the
last 20 years.
5. Locate and operate regional well fields and
recharge facilities so as to manage withdrawals
and replacements (recharge) scientifically. Well
fields should be hooked up into regional
systems much as the electrical industry has
done their generator plants and power distri-
bution systems.
6. In areas where water is now being "mined,"
that is pumped out at a rate faster than nature


replaces it, allow no more large-scale water
developments and work to eliminate waste
and extravagant uses of water supplies in such
areas.
7. In the shore zone region which has been
invaded by salt-water encroachment and in
some inland areas containing brackish ground
water, immense supplies of brackish water are
available, particularly in the upper parts of the
Floridan Aquifer of southern Florida. This
water ranges from nearly as salty as the ocean
to only slightly more salty than normal ground
water. Much of it a mile or so inland is only
mildly saline (1,000 to 7,000 mg/1) and can
be economically reclaimed for use. This will
be more costly than use of fresh water (if it
were locally available), but is comparable to
the cost of developing and transporting fresh
water from distant well fields. Some day we
will do this on a large scale, and it may not
be far off, particularly if the coastal counties
cannot import the fresh water they will need
to obtain from outside their county bound-
aries. We must remember that the coastal
counties are at the downstream end of nature's
pipeline; the upstream end is in those inland
counties mostly to the cast, and is included
within the boundaries of the Southwest Flor-
ida Water Management District.
8. Import water from distances up to several
hundred miles, such as from the aquifer up-
gradient from Weekiwachee Springs, Chassa-
howitzka Springs, Homosassa Springs, Crystal
River Springs and others, or even farther,
from such large north Florida streams as the
Suwannee or Apalachicola. But this will be
costly, probably much more costly than any
other means previously mentioned. Nonethe-

less, it has been done elsewhere in places
such as Boston, New York, Los Angeles, San
Francisco and Denver; it could also be done
here. Hydrologic and engineering studies will
have to be made by the District to evaluate
just how much these alternatives will cost.
Then, with such knowledge, the taxpayers
will be in a position to make the necessary
choices.

E. Mine the aquifers. The Floridan Aquifer and its
overlying shallow system of water table and low
pressure artesian zones contain far more water in
storage than all the Great Lakes combined. In
the District, for example, the upper 1,000 feet
or more is generally filled with fresh water inland


-(__ --------- ,*.-- ----- .-AL- ----1 --4m -L_.


-~ --LLu*u~Yi,,d~Li~--C-l__ri I






from the 25-foot contour on the p ,ntiometric
surface. However, salt water undcrli*s this aqui-
fer system everywhere and boundS it on the
C west all along the shore. If the aquifer is over-
pumped, salt-water -encroachment slowly but
eventually follows. Tampa and St. Petersburg,
to name only 2 large users, lost their original
coastal zone well fields to salt-water encroach-
ment in the 1920's; now other coastal cities,
0 such as New Port Richcy, are undergoing the
same loss. Additionally, thousands of private
wells in the shore zone that extends generally
inland from the Gulf of Mexico to about the
10-foot contour on the potentiometric surface
either have been ruined by salt-water encroach-
ment or are in imminent danger of the same
fate. And this is extremely serious because this


zone includes mosof our rapidly urbanizing
area where the largest amounts of water will be
needed to supply its burgeoning population.
Great care must be taken that the aquifer not
be mined of its fresh water with resultant salt-
water encroachment. Detailed research is cur-
rently underway to develop better knowledge of
the aquifer's hydrologic characteristics so that
realistic, effective management decisions can be
reached.

Right now we have considerable generalized
and some specific information and hydrologic
understandings that will serve to guide us until
better and more detailed data are available: We can
make do, then, for awhile. But, we can't afford to
dally. The situation is upon us now.


__ __


I ., I- I'll "1 11, 1 i 1. 11 4 1., 4L I




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