Title: Water Crop, Draft
Full Citation
Permanent Link: http://ufdc.ufl.edu/WL00002241/00001
 Material Information
Title: Water Crop, Draft
Physical Description: Book
Language: English
Publisher: SWFWMD
Spatial Coverage: North America -- United States of America -- Florida
Abstract: Water Crop, Draft
General Note: Box 10, Folder 12 ( SF Water Rights-Water Crop - 1973, 1976-77 ), Item 5
Funding: Digitized by the Legal Technology Institute in the Levin College of Law at the University of Florida.
 Record Information
Bibliographic ID: WL00002241
Volume ID: VID00001
Source Institution: Levin College of Law, University of Florida
Holding Location: Levin College of Law, University of Florida
Rights Management: All rights reserved by the source institution and holding location.

Full Text




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Governing Board

Derrill S. McAteer
J. R. Graw
Thomas M. Van der Veer
Joe E. Hill
N. Brooks Johns
S. C. Bexley
Ronald B. Lambert
Robert Martinez
George Ruppel
Latimer H. Turner

Vice Chairmen
Assistant Secretary
Assistant Secretary

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I L I I i I


In/est Xentral Florida, we depend upon water -- an adequate supply of

it -- for our physical and economic health. Almost all of our major industries

and commercial pursuits are water-dependent enterprises:

Few industries depend so heavily upon irrigation as Florida's

citrus growers. Their crops represent about $1 billion in cash

receipts to the Florida economy annually.

Our vegetable farmers and ornamental horticulturists likewise

must have sufficient water for irrigation. Their cash receipts bring

approximately $486.2 million to the state each year.

Many Florida ranchers and dairymen need large quantities of

water to maintain improved pastures during the annual dry months.

These industries generate cash receipts totalling $510 million.

The phosphate industry, with more than 11,000 employees and

a payroll of $137 million has an estimated impact on florida's

economy of $3 billion yearly. From central Florida's phosphate

mines comes an indispensable component of the fertilizer America's

farmers must have to avert a world-wide food shortage. Yet, to

keep these mines operating, to keep this valuable ore moving to

port, requires massive quantities of water: about 251 million gallons

per day.

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Even our multi-million-dollar tourist tra depends indirectly

upon water. According to a Florida Department of Commerce survey,

the state's primary attraction for tourists is water, water sports,

and water-related activities. And 27.2 million visitors spend

$8.8 billion in Florida each year.

Finally, and with probably the most immediate importance to

each of us personally, is Public Water Supply. Distribution of

water to millions of persons by city and county water systems is

not only of deep personal importance to those users, but is also

big business and big money providing these local governments with

much needed additional income. L.ets.f water means more hook ups,

more income, more dollars in circulationand a healthier city or

county budget. Such uses throughout the District total something

like 217.4 million gallons per day. Pinellas County alone averages

77.9 MGD and St. Petersburg averages 34.5 MGD. AhVW AWIR4 l' Al A.

IS THERE ANYONE IN THE DISTRICT WHOSE livelihood does not depend, directly

or indirectly, upon the health of these industries?

IF THERE ISN'T SUFFICIENT WATER to sustain these industries and jk46

employees, can a store manager, a realtor, a trucker banker hope to prosper?

If retail sales decline, where will advertising dollars and sales commissions
come from? If the general economy declines, how will tax revenues --- and

public service programs supported by tax dollars --- be affected?

THIS IS NOT A DOOMSDAY PREDICTION of an imminent water shortage that could

cause these industries (and all the offices and businesses that are related to
v i
them in th4s complex economy ofeowurs to collapse or to force massive layoffs.

THIS IS, HOWEV, AN EMPHATIC STATEMENT that water is a valuable natural

resource. For Floridans, it is our economic lifeblood. We can no longer assume

that a sufficient water supply will always be available. If we are all to

prosper, this precious resource must be managed properly to insure that all our

domestic and industrial needs are met.


"A THOUSAND GALLONS PER DAY PER ACRE" has been repeated so often in public

hearings at the Southwest Florida Water Management District regarding consumptive

use of water that is has almost become a slogan. Where did the figure come from?

From data compiled from years of research by the District and the U. S. Geological


FIRST, IT'S NECESSARY to establish how much water there is

before we can talk about how much is available for human use. There

are three natural sources of water: (1) Precipitation (rainfall);

(2) Ground Water (water that exixts or flows into an area beneath

the ground); and (3) Surface Water (rivers and streams).

BECAUSE DISTRICT BOUNDARIES are based upon natural watershed

Basins, there are no rivers originating outside the District and

flowing into the District and hydrologic data indicates that there

is virtually no round, ater inflow into the District. Therefore,

our only source of water in this part of Florida is rainfall. ffm

Sjecords of the Geological Survey and the U. S. Weather Service tell
us that, on a District-wide basis, we-wi44 average 52 inches of

precipitation per year.

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NOW, WC HAPPENS to the rain after it ias? The Geological

Survey, through the use of continuous recorders on District rivers,

tells us that 2.3 trillion gallons flow into the Gulf during an
average year. That's the equivalent of 13 inches of rain falling on
the District's 10,000 square miles.

The remaining 39 inches (52 inches of precipitation (P) minus

13 inches of Runoff (R) = 39 inches) is lost to a joint process known
as Evapotranspiration (Et): evaporation and plant transpiration.

With this dataL District hydrologists are able to use a formula

(developed decades ago) which could be used to establish a water budget:

Precipitation (P) = Runoff (R) + Evapotranspiration (Et)
P = 52 inches

R = 13 inches
Et = 39 inches

P(52) Et(39) = R(13)

There is nothing we can do to increase rainfall. There is little

we can do to reduce Et. Therefore, we have to live with the remaining
13 inches of runoff. This becomes our harvest, or crop.

Let's reduce this District-wide average of 13 inches to a figure

that is easier to see:
13 inches x 10,000 square miles (District Area)
=.2.3 trillion gallons per year

2.3 trillion gallons per year divided by 10,000
= 233 million gallons per year/square mile

233 million gallons per year divided by 365 days
= 640,000 gallons per day per square mile

640,000 gallons-per day/square mile
= 1,000 gallong per day per acre.

THUS, 1,000 GALLONS OF WAJER per day per acre'is nothing more and nothing

less than the average amount of rain which normally falls on a given area and

is not lost to evaporation or transpiration. This amount can be considered

available for man's use. It is the WATER CROP.


A WATER BUDGET IS MUCH LIKE a household checking account, and similarly you

can't "spend" more water than Nature puts into the aquifer without obvious,

immediate effects. Just as an individual can't take more dollars out of his

account than he has deposited. Using another analogy, water in the massive

Floridan Aquifer is much like a savings account; it can be drawn down -- to a

limited extent -- during dry months or even dry years if comparable "deposits"

are made during rainy months and wet years to replenish the account. BUT WE DARE

NOT draw it down too much or for too long. We cannot,for:an extended length of

time, remove water faster than it is being replenished without upsetting the

Hydrologic Balance of Nature, that delicate equilibrium between salt and fresh

water and between ground and surface water.

IF WE CHOOSE TO IGNORE OUR WATER BUDGET and continue to remove more than is

being replenished (mining water) on a massive scale, this is what can result:

(1) As the water table aquifer level begins to drop, small domestic wells

would become gradually less effective. Water would have to be pumped from a

1 greater depth and more power would be required to lift the same quantities.
(2) Lakes and streams would also begin to show the effect. As the difference


in pressure between the artesian aquifer and the water table aquifer increases,

greater recharge takes place. The effect: lower lakes, stress on trees and

shrubs if the levels drop below root zones, rivers become creeks, and creeks

become dry runs.

(3) Salt water would begin to move inland and upward. All along our coast-

line, the fresh water of the Floridan Aquifer meets the salt water of the Gulf

and the Atlantic. Salt water underlies Florida at various depths throughout

the peninsula. Remove the fresh water, as would happen if water mining were

allowed on a continuing basis, and salt water will move to replace it. This

is what happens when a well loes salty.


The Board has established the Consumptive Use rule so that all applicants

will know the yard stick being applied on a District-wide basis. Under the water

crop concept there is an average 365,000 gallons available per acre each year.

For the health, welfare, and best interests of the public throughout the

District, as well as for the protection of the water resource, that 365,000

gallon annual total water crop should not be exceeded.

But the day when man is using every 1,000 gallons from every acre in the

.District in some time in the future. Although mining of water is occurring in

some specific area, by and large there is no demand for the total water crop

throughout most of the District.

It is practical, then, that some water users primarily cities, counties,

and some major industries who own wellfields are allowed to take huge quantities

Sof water from relatively small areas. This is because there is enough runoff,

or water crop, from adjacent lands to supply the demand and prevent mining from

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occurring. It is also because these consumptive users have shown that their

- use of water is for a reasonable, beneficial purpose and that it does not

interfere with any presently existing legal use and is consistent with the

public interest.

It must be remembered, that the water crop is not the sole criteria upon

which the District bases its Consumptive Use Rules. The concept is a valid

water management tool, and is used by the staff and the Board in determining

the appropriatness of a request for water use. It is used as a guideline and

represents the best information presently available for establishing the total

amount of water available and regulatory levels. It is the best tool that has

been brought forward to assist the District's ;overningin protecting the

public interest and the resourcelas the law requires the Board to do. It is

a guideline that is continually being refined.

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