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LIST OF PARTIES TO TESTIFY AT MIAMI CANAL LOCK HEARIIIG
TO BE HELD JULY 11, 1946
EARLE 1M. READER
"' JOHN C. STEFHENS
1GERALD G(. PARKER
7, DEA B. BOGART
8. i.: A. GLASS
9. C. F. WERTZ
Vice-Chairman of the Board of County Commiesioners
and acting for the chairman who is out of the city.
County Engineer for Dade County, Florida.
Attorney for Board of County Commissioners.
Consulting Engineer for Dade County's Water
Dade County Water Control Engineer
Geologist, U. S. Geological Survey,
in charge of ground water resources
investigations in Southeastern Florida
Associate Engineer in charge of Surface Water
Division of U. S. Geological Survey
Sin Southeastern Florida
Director.of the Department of Water and Sewers
/ for the City of Miami. (Will present report by
Malcolm Pirnie, outstanding authority on
--water"resou rces matters.)
Resident Engineer for Day and Zimmerman,
Consulting Engineers, assigned to the
City of Miami Department of Water and Sewers.
DR. T. E. CATO
LAMAR JOII SON
DR. JOHN G. DUPUIS,
DR. JOHI C. GIFFORD
JOmi HURST '.
Health Commissioner for Dade County.
.President of Board of Commissioners,
Everglades Drainage District, and
large property owner in Northwest Dade County.
Engineer for Board of Commissioners of
.Everglades Drainage District
Physician, early settler, large scale farmer,
large .scale dairyman and President of the Little
River Valley Drainage District.
Noted Horticulturist, plant explorer and
University of Miami professor. .,.
Early settler and President of the:
Florida Well Drillers Association.
. r I
SU. H. GALLATIN
:DR. R. V. ALLISON
EUSTACE L. ADAMS
Soil Scientist, U. S, Department of Agriculture.
(Will present a statement by Dr. Geo, B. Ruhle,
Plant Pathologist with the University of Florida
Agricultural Experimental Station in charge of
sub-tropical Experimental Station, Homestead, Fla.)
Soil Chemist of the University of Florida
Agricultural Experimental Station
and in charge of the Everglades Experimental-
Station, Belle Glade, Florida
Noted author and representative of Dade County
Conservation Council and Miami Rod and Reel Club
of Florida Wild Life Federation.
... B BY
BOARD OF COUIISSIONERS, EVERGLADES DRAINAGE DISTRICT
WHEREAS, the BOARD OF COUNTY COMMISSIONERS OF DADE .,.
COUNTY, as and constituting the WATER CONSERVATION DISTRICT OF
DADE COUNTY, FLORIDA, has applied to the War Department for per-
mission to construct a water control dam with navigation looks
in the Miami Canal; ..and
WHEREAS, EVERGLADES DRAINAGE DISTRICT is charged by law
with the responsibility of regulating the water levels, canal
stages and the outlet capacity of canals within said District,
for the purposes of agriculture, sanitation and for the public :
utility and benefit; and : ,' :..: : :
YWEREAS, THE BOARD OF COMMISSIONERS OF EVERGLADES DRAIN-
AGE DISTRICT has considered the design and plans of the structure:
proposed and is satisfied that said design and plans provide for
an adequate regulation of canal stages and the discharge of flood
waters; and that they a re further assured that the structure will
contribute to the general betterment of water control conditions,'
including prevention of the intrusion of salt waters.,
NOW, THEREFORE, BE IT RESOLVED by the BOARD OF COMMIS-
SIONERS OF EVERGLADES DRAINAGE DISTRICT, a;:a regular meeting held
in West Palm Beach, Florida, on July 5, 1946, that the War Depart-
ment be, and is hereby, requested to grant he request of the
BOARD OF COMMISSIONERS OF DADE COUNTY as and constituting the
WATER CONSERVATION DISTRICT OF DADE COUNTY, FLORIDA, for permission
to construct the said water control dam in the Miami Canal, and
does assure the War Department that the granting of such request
is not in conflict with the plans of EVERGLADES DRAINAGE DISTRICT
or its legal rights and interests in the premises.
BE IT FURTHER RESOLVED, that nothing contained in
this Resolution relinquishes or waives any statutory duty or
authority of the EVERGLADES DRAINAGE DISTRICT.
STATE OF FLORIDA )
COUIITY OF PALM BEACH)
SI, K. M. THROOP, Secretary, hereby certify that the
above and foregoing is a true and correct copy of an excerpt
from the minutes of a'meeting of the BOARD OF COMMISSIOITERS OF
EVERGLADES DRAINAGE DISTRICT held at West Palm Beach, Florida,
on July 5, 1946.
SWITNESS my signature and official seal of the EVER-
GLADES DRAINAGE DISTRICT at West Palm Beach, in the County of
Palm Beach, and State of Florida, this 8th day of July, 1946.
(Signed) K. M. Throop
Secretary, BOARD OF COMMISSIONERS
OF EVERGLADES DRAIIAGE DISTRICT
r --- ---- -- ----.--.- ..r I
Presentation at U. S. Engineer office hearing July 11, 1946 on
permit to construct lock and dam in Miami River at IW. 20th Street, Miami.
Extent and Nature of Intrusion of Salty Water
in Canals in Southeastern Florida
As already described to you salt water contamination of the ground
water concentrically with the inner coast of Southeastern Florida and
along the tidal canals was a direct result of drainage operations and
associated lowering of the fresh water table. Tongues of salty water
moved up the canals and caused contamination far in advance of the slower
basic intrusion. It was a relatively swift action and varied in extent
from year to year seasonally.
The contamination of canals in some degree by salty sea water occurred
prior to 1939 but it was then that the situation in Miami Canal indicated
the need for intensive- study and possible remedy. Excessively saline water
was found in Miami Canal, then not controlled, nearly 11 miles from
Biscayne Bay or about 3 miles west of the municipal well field. It was
in this period that a number of the wells were rendered useless as sources
of drinking water. Since 1943, sea water has been prevented from proceeding
farther up Miami Canal than Hialeah by temporary dams near 36th Street,
Miami. There is little doubt that these dams prevented the intrusion
from extending many miles farther inland. The large rock pits in the
lower Miami and Tamiami basins, however, were outside of the protection
of the dams and became strongly salty.
Following a series of dry years, the situation became extreme in the
spring and summer of 1945 as canal and ground water levels declined to
what were possibly all-time lows. In the then uncontrolled Little River
and Biscayne Canals strongly salty water existed throughout their entire
lengths. Water with a salt concentration of about 75, of that of sea:
water was seen running into the porous ground at the western ends of the
canals. It did not go farther by canal only because the bottom of Red
Road Canal and its laterals was slightly higher than the salty water in
the tidal larger canals.
In 1945 salty water penetrated west of Florida Highway 149 in Snake
Creek Canal, despite its.weed and debris choked condition. In Tamiami Canal
excessive salinity was found at the West Flagler Street bridge. Salty water
went west of F. E. C. Railway (inland branch) in Coral Gables Canal; past
U. S. Highway i in Snapper Creek Canal* In the Homestead-Fiorida City area
all of the uncontrolled and partially controlled canals were heavily saline
throughout, with many of the lateral ditches contaminated. Concentrations
were in some places 20 to 30 percent higher than that of normal sea water,
due to evaporation. Along the affected canals reports were receivedabout
soil and water made unfit for agricultural, commercial, and domestic use.
Sea water moves in a canal as affected by tidal variations and fresh
water runoff. As the amount of fresh water coining down a canal decreases
the salt water in the bay or ocean begins to move inland. It proceeds in an
alternately advancing and retreating action under influence of the tides
and it lays in the lower part of the canal under the fresh water. Sea water
in this area has a specific gravity as high as 1.03 and in a canal exists
as a density current. At times there is fresh water running toward the
- ~ ~ '':;
sea in the upper part of the canal and salty water running inlind beneath
it, with a considerable velocity in both directions and no appreciable
transition zone betweeithe two layers.
The inland trend continues as the amount of fresh water coming from
the back country decreases. Somewhere along the canal a point is con-
tinuously reached where the effect of the fresh water runoff equals the
effect of the inland moving salty water. And when the level in the canal
declines nearly to that in the sea, the rate of intrusion is accelerated
and that portion of the canal becomes quickly contaminated. Under these
conditions the whole cross-section of the canal becomes salty and there
is no separation between the two kinds of water. Such occurred in 1945
with resultant pouring of salty water into the porous formations along the
It has been observed that within a month or so, with heavy rainfall,
it is possible for conditions in the canals to become entirely reversed
with fresh water forcing the salty water back toward the sea. The canals
then become comparatively uncontaminated except in the lower reaches of
the larger ones. But the salty water in the ground does not dissipate
so quickly and remains to cause possible trouble. And the rock pits do'
not become fresh because the entrances are considerably.above the bottoms
and the heavier salty water cannot escape down the canals. The pits have
in the last several years remained salty during the wet seasons.
It should be pointed out that in any year of scanty rainfall and
with uncontrolled canals extreme intrusion of salty water can occur.
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July 10, 1946
SI am Dr. T. E. Cato, Director of the Dade County Health Unit
which is the Department of Public Health for the,City of Miami,
Miami Beach, Coral Gables, and all of Dade County.
Certain special interests in Miami have opposed the construo-
tion of a lock in the Miami river, In order to block the construc-
tion of this lock and force the removal of the well fields to the
everglades, these people have not confined their opposition to
economic and legitimate grounds. They have, unfortunately, attempted
to cause fear in the minds of the people of Miami concerning:the
purity of their water supply now, and after the dam has been com-
The purity of water is something that can be measured as easily
as the purity of gold or silver can be determined. There is no
question as to the amount of silver in a silver dollar because it
is a matter of record and is easily determined. There is no question
as to the purity of Miami!s water because it is a matter of record
and is easily determined.
The construction of a dam in the Miami river will not cause
pollution of Miami's water supply. There will still be the same
depth of sand and rook that the water necessarily must filter
through before it reaches the wells, and the raising of the water
level will not influence the amount of sand through which this
water must filter.
There are definite standards for drinking water that have been
established by the Federal Government. Miami's water supply more
than meets these standards. The people of Miami can rest assured
that they have a pure and safe water supply and that they will have
a pure and safe water supply after the dam has been constructed,
In conclusion I,will say that the City of Miami's water supply
well field is not polluted and will not be polluted in the future
because the Dade County Health Unit through the exercise of its
regulations and police power will see to it that it does not become
(.Si ned) T. E.: Cato
T. E. Cato, M.D.
TEC:ah Health Commissioner
AGRICULTURAL EXPERIMENT STATIONS
Everglades Experiment Station
Belle Glade, Florida
Colonel A. B. Jones, District Engineer
U. S. Engineer Office
Re: Soil and Water Conservation in
Relation to Miami River Improve-
; In considering the problem of soil and water conservation in the
Everglades there frequently comes to mind the terms with which I once
heard Mr. Arthur E. Morgan, when Chairman of the Tennessee Valley
Authority, characterize our national wastefulness and profligacy in
the handling of our phosphate resources while discussing this subject
Sin a regional conference in Chattanooga back in 1936. Naturally the
impression made by his remarks was considerably enlarged and extended
: when, in the course of a later review of this same subject at the
University of Florida in Gainesville, Doctor Morgan, former President
of the University of Tennessee and immediate successor of A, E. Morgan
Sas Chairman of the Tennessee Valley Authority, used precisely the same
: words and essentially the same vehemence in setting forth his own equally
deep feelings of despair in the matter. Nhat both of these gentlemen
said in classifying and characterizing the retributions to come was that
"FUTURE GENERATIONS WILL RISE UP AND SPEAR OUR GRAVES...'."
Now I suspect that if I were to undertake to discuss the terrifying
waste and economic losses of the past in handling our soil and water re-
sources of the Everglades in these same general terms some of us would
Col. Jones, page 2
have plenty of cause to anticipate that our graves would not only be
speared again and again but that those spears even would be waggled
around until they do actually find us.
There can be no doubt in the mind of anyone who has critically
examined the situation that the soil resources of the Everglades have
been most miserably punished in the past, especially through the inade-
quate handling of the natural water supply by which they should be pro-
tected. This has been due in large part, of course, to lack of equipment
and personnel for the purpose. Thus it largely boils down to the inadequacy
of the reclamation plans that have been developed in the past, especially
from the standpoint of water conservation ani all that it stands for in
terms of soil conservation, municipal water supply, wild life protection
and development, availability of irrigation water and the possible amelio-
ration of winter temperatures, to-mention only a few benefits.
With the above facts in mind I wish to include in the record of this
hearing a copy of Volume V-A of the Proceedings of the Soil Science Society
of Florida which is a complete and comprehensive report on a special,
interim meeting of the Society held in Belle Glade in March of 1943 for
a careful discussion of the physical and economic problems of this great
area. In this volume are to be found numerous papers that treat in con-
siderable detail of the relationships existing between geological and
climatological factors in the formation of these soils and of their practi-
cal use limitations at the present time. In view of the availability of
this information in this form I shall include with the present discussion
as exhibits;ionly a limited number of photographs selected largely from
the field trip reported on pages177-187, inclusive, in the'appendix at
'l. Jones, page 3 "
Sthe back. These will serve to show the intimate and inseparable relation
Sof the water problems of the whole area to those of the Southeastern
section thereof, ,which is the principal area under discussion in this
SThus, Exhibits II, III and IV as located on the map of Exhibit I,
clearly show the importance of the subsidence factor in the handling of
peat and muck soils and the manner in which water can be controlled even
S in our main canals while Exhibit V illustrates the great fires that have
S swept the whole area, time and again, when the water table has been per-
mitted to fall so low as to fail in the natural protection such soils
Must have from this source if they are to survive even a reasonable period
: of use. Incidentally the fire in the lower picture of Exhibit V is in
the openarea to. the north and west of Pennsuco where extensive areas :n
S : of the shallow peat have been burned practically to the underlying rock
except, of course, in the deeper potholes. The topographic map of Exhibit
.VI, the soils map of Exhibit VII, the geological maps of Exhibits VIII,
:: and IX and.the map showing the approximate direction of surface flow in
Exhibit X are -all helpful in indicating the general trend of surface
elevation from north to south, the very important change in type and depth
of organic soils as one progresses southwards in the direction of the
Miami area, and the type aid distribution of the underlying rock which is
proving such an important factor from the water control standpoint. Exhibits
XI and XIL/ display in still greater detail the distribution and character
Sof the Miami Oolite and other highly porous lime rocks in that section
that shall doubtless find such an important place in this hearing. As a
matter of fact it would seem logical to believe that the leaky floor in
Co l. Jones, page 4
this section of the Glades is quite appreciably accountable for the shallow
depths of the original organic mantle to the south since it places the
formation of peat under such conditions in somewhat the same position
youa or I would find ourselves if we were to undertake the processing of
S, sauerkraut in a, barrel with its bottom full of holes.
There can be no question that this conservation approach has very
Definitely assisted in the development of a broader understanding of the
Whole Everglades problem during the past few years, as has also the cordial
and helpful cooperation which the Officials of the U. S. Engineer Office
have so consistently given us whenever it has been found consistent with
the responsibility of their office to do so. It must be emphasized,
however, that to the extent our understanding of the whole problem has
S ,become more clearly defined, to that same extent has our appreciation
been heightened that the general pattern is made up of a large number
Sof individual problems which always must be treated in their relation
to each other and to the hole project if a return to the confusion
of the past is to be avoided. Thus the question of how best to handle
the .local water .supply that is under discussion here today is truly typical
of one of those local problems and I sincerely trust that its consideration
as a problem separate and apart from the whole will not be indulged in
any way at ny time.
Thus when a resolution was moved in the course of the Belle Glade
meeting of.the Soil Science Society of Florida bac: in 1943 that con-
d; taintedd as its very heart the request "That the Everglades Drainage
S.District .... assume responsibility for the development of an OVER-ALL
..; .: POLICY AID PLAN for the future conservation and development of the land
Col. Jones,:page 5
and water resources of the Everglades and .... serve as the CENTRAL
AUTHORITY to coordinate the activities of all private and governmental
agencies in the execution of such plan" it represented quite a far cry 1
from the approach thd; had prevailed up to that time, as Mr. Mark R.
Tennant, the Chairman of the Everglades Board at that time, will tell
It is significant, too, that the resolution also asked "that Ever-
glades Drainage District arrange a joint meeting witththe Trustees of
the Internal Improvement Fund and State Officials in Tallahassee to be
attended by representatives of all interested agencies to discuss matters
of policy and the steps to be taken towards the adoption of a plan and
establishment of the District as the required, CENTRAL AUTHORITY". 'Such
a meeting was held about a month later (April 1943) in Tallahassee under
the general Chairmanship of Governor Holland and with th. particular
assistance of Commissioner Mayo and Mr. Tennant. The real significance
of that part of the resolution stems from the fact that the Tallahassee
meeting proved a tremendous source of inspiration for each and every one
of the eighty or more who attended, including, I believe, no one quite
so much as the Governor himself. For there could be no greater harmony
of thought or unanimity of opinion than prevailed in that meeting when
the question of centralizing authority over Everglades affairs in the
Board of Commissioners of the Everyglades Drainage District was definitely
brought forward. The entire group, to the very last member of the Cabinet,
was entirely favorable to the proposition and Governor Holland closed the
meeting by turning the decision over to the Everglades Board essentially
as a mandate and urging that the details be worked out as rapidly as
Col. Jones, page 6
While the progress of this conversion to such a broadly different
basis of operation on the part of the Board, due, among other things,
to lack of funds for essential operations, has not been so rapid as to
dazzle, it assuredly has been steady, straightforward and substantial.
That real. advances have been made is well indicated, for instance, when
responsibility and authority for the construction and operation of all
works and installations within the District, once they are approved by
the Board, was recently turned over to its Chief Engineer.
Perhaps an even better indication of the change that is taking place
is to be found in the manner in which Dade County Authorities have worked
with the Everglades District Board and its Engineer in developing the plan
and design for the Miami River structure now under discussion which will
assume such an important role in one of the Distric-s principal outlets
in this section of the Everglades if and when it is constructed; for such
harmony in the planning of such important local facilities can not but
develop the hope that coordination and cooperation in the Phole plan of
construction and of operation of the facilities of the District, for which
we have waited so long, may be in the process of development.
As a matter of fact, Colonel Jones, if the report of your findings
proves favorable to the development of this control in the Miami River
and it is constructed and operated under the joint supervision of County
and District Authorities to the very best interest of the several purposes
which it can so effectively serve rather than for any particular interest
to the disproportionate detriment of one or more of the others then I
can see in this hearing one of the really great moments in the life of the
Col. Jones, .page 7
Everglades or at least in the life and future of that portion of it which
is still left to us.
In closing I would like to reemphasize briefly, but just as seriously
as possible, the principal point I have tried to bring out in this discussion
namely, the importance of water conservation in and on the land.for a number
of purposes but above all else the protection of the land itself.
.. A fact that too few people realize, at least so it seems to me, is
that the monetary values we attach to the soil and to the land are for
purposes of barter only and do not, in any real sense of the word, repre-
,,sent absolute or net values. For the soil by which we live is, in the
broader sense of the word, above and beyond value much the same as human
life. Unfortunately we too frequently realize this only after it is
seriously impaired or hopelessly destroyed. ihile we may endure a certain
Amount of damage to it, locally for a time, it is, nevertheless, always
dangerous for we know from history that when the land of a Nation is beaten
S down and destroyed then that Nation, as a Nation, also is dead. The same
S is true, of course, for local areas insofar as agriculture is concerned.
S .. It is on this account that I have repeatedly asked myself and am now
asking you the very poignant question "Where is the agriculture of the
Everglades going when the Glades no longer can be farmed?" For this, yoa
must understand, is not merely a question in passing but one that is based
Fairly and squarely on the recorded subsidence of these organic soils.
This trend is especially critical, of course, in the main sections d the
Everglades where the organic mantle is directly underlain by lime rock.
This rate of subsidence is well shown in Exhibit XIII and is influenced
directly by (1) depth to water table and (2) amount and character of culti-
Col. Jones, page 8
ovation. It is not difficult to imagine that quite aside from the great fires
that raged over the Everglades in 1943, when the water fell so low, even
in the central Glades, that the table was in the rock itself, where the
muck was 5 feet or more deep, that this was the most brutal treatment
that possibly could be given this land, for enormous losses by shrinkage
and oxidation were caused thereby quite aside, it should be emphasized,
from the actual burning which it sustained as a result of those conditions.
Among the salient facts relating to the handling of water that we
must keep in mind as the basis for the most constructive system of recla- -
mation we can possibly develop for the Everglades or for any section of
it, the following, to my way of thinking, stand out as particularly
(1) The total water supply coming to the Everglades area, or to any
section of it, actually provides little for wasting. If the needs are
fully recognized and are to be even reasonably well satisfied, conserva-
tion must be the watchword.
(2) The water conservation viewpoint must be kept irrevocably
geared to the job or jobs that water must do with a strict avoidance of
partiality if a well balanced result is to be attained. Soil conservation,
municipal water supply, wild life protection and development, irrigation
and amelioration of winter temperatures are among the jobs which only
water can do, any one of which, however, is worthy of practically any amount
of effort required for its attainment.
(3) Finally, we must keep in mind that (A) regardless of local soil
values, carefully planned water reserve areas are an utterly indispensable
Col. Jones, page 9
part of a successful water control system for such a low-lying, flatland
area as the Everglades; (B) if storage areas are not planned for water
in times of abundance or excess, and well organized facilities available
for delivering it to these areas, then the surplus largely willbe dissi-
pated, as in the past; .(C) notwithstanding the availability of disposal
facilities for whatever purpose and to whatever places, flash flood con-
ditions can not be cared for with sufficient promptness, in a great fl t-
land area suoh as we have to deal with, without doing appreciable damage;
but that (D) a flood is always of much less permanent damage to the land
than a fire especially if plans have beenmade and facilities prepared
en advance and fstore p
in advance to store just as much of the surplus water as possible for
future protection against the time it definitely will be needed for one
or more, if not all, of the highly worth-while purposes listed above.
If the structure in question is installed in the Miami River and
operated in the interest of maintaining water reserves in the open Glades'
in the interest of soil conservation, wild life protection and development,
irrigation and the amelioration of winter temperatures it is sincerely
believed that this facility will be found an economic benefit even aside
from its very great value to the municipal water supply of Greater Miami
which is certain to increase at a great.rate in the years to come, that is
if the naturally expanding requirement for water in this area is not itself
prevented by the shortcomings of the manner in which the problem of future
supply is handled.:' "' "
Everglades Experiment Station
Belle Glade, Florida
July 11, 1946, '
FAIRCHILD TROPICAL GARDEN
in Coral Gables Box 407
Coconut Grove, Fla.
National Geographic Society
.. W. ashington, D. C.
July 2nd, 1946
Col. A. B. Jones
U. S. Engineer's Office:
SDear Colonel' Jones:
SIt would have been a pleasure,to meet you and discuss the salt
water seepage control question. It is too important, fraught with too
great dangers to a growing community to be settled in an ordinary way by
people coming to the committee table with prejudices, personal or official,
and using their influence to swing the decision their way.
SThe question of who will benefit immediately or ho behurt
immediately by the decision, will look small after a few years have passed.
I come into the discussion as a Federal Department of Agriculture
Expert on Tropical Plants, one. who has watched the growth in this region
-of thousands of introduced plants from all over the Tropics. I had charge
of the organization of the Federal Office of Plant Introduction in Washington
and through it brought in thousands of new and valuable plants from Tropical
and Sub-tropical regions. These were grown and tested here and later
distributed to the residents pf this whole area.
In 1898 a Plant Introduction Garden was established, when Miami was
a small village and nothing much was known about conditions for growing
plants here, except the remarkable fact that a few feet below the surface of
the ground there was an inexhaustable supply of fresh water.' It was ay busi-
@ ness to study the conditions required by the new crops so as to fit them into
the agriculture which was growing up about the little town.
The tCnm has grown enormously -- the Government Introduction Garden has
been removed from a little six acre tract to one of approximately eight hundred
acres and the Government monies spent on it increased in proportion.
Today there exists nowhere else in the Western Hemisphere such a collection
of authenticated foreign economic plants as that in the Government Garden in
Chapman Field; even devastated as it was by the storm of September last.
The records of observations pertaining to these plants cannot be
equalled outside of the great gardens of Ceylon and Java.
This work has gone on in spite of all the discouragements that have been
occasioned by the freezes, hurricanes, and drouths which have visited the Miami
region. The Garden now is slowly recovering from its worst oatastrophy, the
S September Hurricane of 1945.
These climatic difficulties were not at first anticipated, but we met
them, and such plants as could stand up against them have been increased and
have become New Industries here. I have only to cite the Avocado and Mango
industries as examples and the Cattle industry was contributed to substantially
through the introduction of the Para grass and other grasses and legumes.
Now to discover after half a century of work and the expenditure of a
considerable sum of money, that the drainage of the Everglades, in which many
of the residents came to believe turns out to be fraught with perils to our
plants is to say the least mosbdisturbing.
Through the years since 1898 home owners here have boasted of having
below their gardens and groves perpetually flowing fresh water; -- in our favor
as against the strongly alkaline, calcareous, sandy and rocky soils. We banked
on this fresh water that crept upward in the rooks and prevented the drouths
from killing the trees.
Because of these conditions, which we had a right to believe were perma--
n ent, the real estate dealers used the fact in good faith as advertising and
induced thousands of people to buy their homes and gardens in this "paradise";
this tropical garden spot around Miami and that stretches along the coast.
Had it been predicted that the shallow wells they drove in their gardens
* would turn salty and the water from them kill their trees and plants, many of them
would not have bought the land at all but gone elsewhere and made their homes. -
lNow, they can say with fairness, I think, that they were deceived, bought
homes under false pretense and have a right to demand thatthe County doevery-
thing in its power to protect their gardens from a danger that was brought about
by the enthusiastic engineers 'who did not foresee this seepage effect which has
come upon them. ...
From freezes and hurricanes and drouths, no human power has yet devised
adequate protection but against this new menace they may be protected. Engineers
Swho have studied the problem carefully say something can be done by controlling
the water flow in the canals. .
Nobody can see the future any more than he can see his hand before his face
on a pitch dark night. But Science has furnished a most amazing new body of
knowledge to the engineers and soil chemists of today, knowledge that the canal
diggers of two decades ago did not dream of' If they.say "Let us try and prevent
this seepage of salt water into the porous rocks underlying your gardens" I believe
they should be given a free hand..
SIf they fail, and the salt continues to invade our garden soils, one thing
can be predicted, because it rests on the knowledge of the effects of salt on
plant roots and the physics of its behaviour in porous rocks; 'both now well
known phenomena. The beautiful tropical vegetation around our dwellings will
be reduced to the few species that can stand salt water, and much of the charm
that our residents came here to enjoy will be gone.
The intellectual and artistic people who should give a high character
to our life here may go elsewhere. Just across the Caribbean lie places of superb
charm and surpassing beauty. IBhey may go there. Those real estate people in.:
the North who have been jealous ofl iami's climate and its growth may urge their
clients to go and build their gardens and orchards where the soil is not becoming -
salty-- across to Central and South America. ,. e :
I i I ~)
' ,. : -"I .,. : ; *''? < / : : / ,' ;- .... ' .'' ** :. ... ** '" ..
The question of salt water seepage in our garden soils and its rise io -the
roots of our orchard trees has a direct bearing on the possibility of Miami being
by-passed by the thousands wao want garden homes beyond the region of cold weather.
SWhat is the use of'the University. of Miami with its program of developing
a Department of Tropical Forestry and Economic Tropical Horticulture; whAt is the
use of making a great collection of pals in the Fairchild Tropical Garden if the
Island in this area is to be allowed,to become unfitted for the growth of tropical
The despoiling of Florida's finest forest scenery has gone very far already.
,May this salt seepage not ruin the tropical gardens which are swinging into
** Very sincerely yours
(Signed) David Fairchild.
D 'avid Fairchild
My name is Melvin H. Gallatin. I am a Soil Scientist,
employed by the S. Department of Agriculture Soil Conservation
Service in cooperation with the Sub-Tropical Experiment Station
of the University of Florida.
For some time various State and Federal organizations have
been trying to obtain data on the relative movement or encroachment
of chloride toward the interior. Because there has been a great
deal of land lo i to agriculture through the encroachment of
chloride, the Soil Conservation Service in cooperation with the
Sub-Tropical Experiment Station set up a study in August, 1945
to study'the movement of chlorides in the marl lands of South
Florida. The geological survey again had funds to-carry on
their operations in connection with chloride intrusion. The
three organizations combined their efforts in trying to get
data on the rate of encroachment of chlorides. The Geological
survey to study the underground and canal movement, the Soil
Conservation Service, surface movement and the Sub-Tropical
.Experiment Station; the tolerance of various t pe of crops to
In February, 1946 when the truck farmers in the Northwest
section of Miami along the Tamiami began having trouble with
chlorides, we set up a sampling area covering this section toTbe
sampled periodically with -two purposes:. (l) to try to obtain
some datf on crop tolerances, (2) to see what the time effect
putting a :salt barrier in the canal would be in improving salt
Table #1 gives the location and p.p. million of chlorides"in this'
area from March 26 to June 10, 1946.
It will be noted since the initial sampling in March that
there has been a constant lowering of the concentration of
chlorides in the surface layer throughout this area. This is due
to the leaching effect of the summer rains.
S This same thing was noted following the hurricane in Sep-
tember, 1945. The resulting high tides raised the concentration
of chlorides in the marl lands East of Allapattah road to around
.10,000 p.p.m. of chlorides and for a time it looked like very
little of the land could be used for agriculture but following
this the rainfall was quite heavy and it was found that because of
the high water table and leaching action of the rain a greater
portion of the area was usable.
Table #2 shows tolerance data we have been able to collect
since the initiation of the project by Dr. Westgate of the Sub-
Tropical Experiment Station and myself.
It will be noted that various types of crops seem to have
a greater tolerance to salt than others. It must be understood
that this data is only presented as an indication and future
work may change it somewhat. Our data at present would indicate
that beans are the least tolerant, followed probably by such crops
in approximate order of tolerance as, gladiolus, onions, straw-
berries, lettuce, corn, tomatoes, potatoes, broccoli, cauliflower
As I stated before our data at present indicates that crop
tolerances will about follow in this order but to date we do not'
have sufficient data to define the exact crop tolerances or to
compute the exact reduction in yield as a function of saline
intensity. However, there is abundant evidence that salt has in
some cases destroyed crops in Dade County and in many cases
materially reduced the yields in both peat and marl lands. Too
from data accumulated to date from leaching effects it would appear
that much of the land now hampered for agricultural production
by salt could be brought back into production at a relatively
early date provided future saline intrusion is. prevented.
'WATER TABLE STUDIES
Effect of High Water Tables in the Everglades Upon the Water Table
in the Rockdale (Limestone Complex and Marl Soil of South Florida)
Data to date collected since the initiation of the water
table studies indicate that as soon as there is no addition to the
water table in the back country the water tables for the area
between the Everglades and the coast drop rapidly. Toward the
end of the winter season, the water table in this back country
was about three and a half to four feet below ground surface.
(Ground elevation approximately 7.0 feet). Vhile at Highland plots
south of Flcrida City with a ground elevation of about 4 feet, we
had a ground water table a little over four feet below ground
surface .19 feet. This low occurred at the end of April. In
May there was recorded about 18 inches of rain at the corner of
Moiry Street and Redland Road. Rains in the back country were
much less as shown by our studies. During the period we had a
rise in the water table in coastal area of from 4 to 5 feet.
Immediately following this we had a period in which very little
rain fell in this area. During this period the well in the-
corner of Mowry Street and Redland Road which is read daily
dr pped about 0.2 of a foot per day. This excessive drop was due
to two factors: (1) there is a free out flow of'water through
canals in the coastal area; (2) the water table in the back
country had not built up, so there was very little recharge from
_ .. i-.;-,-,----~ --
Data at present indicates that when the water table in the
Evvrglades drops to 2 5 feet below ground surface the water tables
throughout this section drop excessively. As a result of this to
maintain good growing conditions, the grove owners must irrigate
If the water table in the back country could be maintained
at a higher level and dams be placed in the coastal canals, we
should be able to hold a higher water table in this area. Pre-
requisites are -- salt barriers and water control structures to
retard flow during low water in all of the presently uncontrolled
canals in this area.
Melvin H. Gallatin
SDEPARTMEIT OF WATER AND SEWERS
CITY OF MIAMI
P. 0. Box 4832
S"Miami. 31, Florida
:July 10,. 1946
Wa. r Department
Jacksonville, Florida :
We are handing you herewith original and three copies
of a Brief in support of the Dade County Engineer Department plan
for water control on the Miami Canal, as presented at the Dade
County Courthouse, Miami, Florida, on July 11, 1946.
There is also enclosed original and three copies of
the statement of Malcolm Pirnie, Consulting Engineer for the De-
partment of Water and Sewers of the City of Miami, as submitted
at the same hearing.:
(Signed) A, Glass
W. A. Glass Diroctor
_ij( I I 1
1 I_ 1_ ( _;-_, ~)
IT SUPPORT OF TE
DADE COUNTY ENGINEER DEPARTMENT PLAN
FOR WATER CONTROL ON THE MIAMI CANAL
W. A. GLASS, DIRECTOR
DEFARTUIENT OF WATER AND SEWERS OF THE CITY OF MIAMI
Presented for the
WAMER AND SEWER BOARD OF IBE CITY OF MIAMI
One of the most serious problems that the citizens of Miami and 4"
Dade County have to solve is that of salt water encroachment. It has already
cost the local taxpayers hundreds of thousands of dollars in actual cash due
to loss of producing wells, many of which can never be reclaimed. Additional
wells are at the present time threatened a potential loss; and the wholw '
salt water encroachment problem is caused by and due to the uncontrolled
Uncontrolled drainage has wrought serious damage to property owners
and taxpayers who own lands on the Coastal Ridge. Drainage was not planned to
affect any land but that in the Everglades; the idea was to remove the water
that flooded the organic soils 'behind the Coastal Ridge and thus open up to
agricultural pursuits a vast, rich, sub-tropical swamp. But the canals that
were dredged out through the swamps also cut through the Coastal Ridge, and
these same canals that were to drain the Everglades nd; only did that, but they
also drained the Coastal Ridge.., "
The drainage canals were mnt designed as water control canals they :':
were to carry away the water from the swamp lands.. And, to a certain extent,
they have been quite successful in achieving this end. The drainage canals in
this County have run open and uncontrolled all the years since they were
dredged, wet years and dry, until, at the insistence of the City of Miami, and
at its own expense, a salt water barrier was temporarily installed in the Miami
Canal near the NW 56th Street Bridge in 1939. The canals have never been ade-
qaate to, carry off flash floods, s'o that Everglades lands are still inundated
at times of extremely heavy rainfall. But during times of low or inadequate
~i ; (_
rainfall the canals continue to siphon off untold billions of gallons of
fresh water, wasting this precious natural resource to the sea. This un-
controlled drainage has not only worked to the disadvantage of dwellers.on
the Coastal Ridge by over-draining the ground water of the Ridge, but by
drying out the organic soils of the Everglades and making them tinder-dry
during the dry season of the year, has allowed the ruinous 'glades fires to
spring up, fouling the air over the Ridge for weeks at a time. These glades
fires are directly a result of uncontrolled drainage. They are not only a
nuisance to the residents of this area but a distinct cause of loss of tourist
trade. Also, by lowering the water surface in the Everglades, our wiinters
have been made more severe the danger of frost to truck farming crops and to
citrus crops has been increased many fold.
Because of these facts the City of Iiami Board of Water and Sewers
takes the position that uncontrolled drainage in Dade County must go, and supports
the County of Dade in its plans for water control. The several factors listed
above are each of significant importance,-but most vital of all is the factor of
salt water encroachment. We believe that had there been no drainage program put
into effect, there would be today no problem of salt water encroachment, and in
this we have the endorsement of the United States Geological Survey whose scien-
tists and engineers have been studying the water resources of Southeastern
Florida since the Fall of 1939.
Salt water encroachment has already ruined two former producing well
fields of the City of Iiami. The first well field.to be.lost was the Spring
Gardens field, located near NW 10th Avenue and 11th Street, now a part of the
SMiami Country Club. This well field was used until 1925 but salt water first
began to be noticed there in 1918. (Major Everglades drainage canals were
begun about 1910 and finished about 1918).
W:: 'hen the Spring Gardens field was first developed, wells were
finished at depths of 60 to 90 feet and water from these wells flowed above
the land surface due to the hydrostatic pressure of ground water impounded in
the rocks up-gradient from the well field. Gradually, as the results of
drainage became felt, the wells ceased flowing and the formerly fresh water
became brackish. To overcome the brackishness, the deeper wells were plugged
up to about 40 or 45 feet, for the heavy salt water was moving in at depth isn
the water-bearing formation and fresh water could still be obtained at shallow
depths. However, even this shallow water finally became salted too badly, and
it was necessary to abandon the field. A new site, 47 miles inland from Biscayne
Bay, on the.eastern margin of the Everglades was chosen*. That site is the
location of the present well field. Part of it lies in Miami Springs and part
in Hialeah. Back in 1925 it was thought that moving the field so far out into
Sthe back-country was an ultra-conservative move, but the facts of the situation
S were not then known.
Then in 1939, certain wells in this new field became salted, some of
them yielding water containing more than 1000 ppm of chloride. At about the
'same time the Coconut Grove well field which is located about a mile from ',
Biscayne Bay and about 5/8 mile easterly from the Coral Gables Deep Waterway.:
began to show salt water contamination. Our public water supply thus threatened,
a request from the Cities of Miami, liami Beach, Coral Gables, and from Dade
: County was sent the United States.Geological Survey to investigate our water '
. 7 r .-r_ ., -r-. . . 1 1. '"
resources. We wanted to know all the facts about our present and past
supplies; the factors controlling this salt water invasion; whether it
*i : could be stopped or not; where other supplies might best be obtained in
case the local supplies were doomed; in other words, a complete investigation.
In the meantime, in spite of all the efforts our water department
engineers employed, no method was found to enable us to continue the use
indefinitely of the.-Coconut Grove field. In desperation an attempt was made
S to obtain water there by digging a huge rectangular pit (essentially a large
Open well) the bottom of which was just about at sea level and slightly below
the water table. However, even this very shallow ground water became highly
.contaminated with sea water and had to be abandoned. The Coconut Grove
well field was dead, the money invested in it entirely gone.
SThus, in the short span of 16 years (1925 to 1941) Greater Miami
had lost two well fields to salt water encrMachment -a:-atiff price'for city
S folks to pay for a drainage program that was intended to make land usable in
the Everglades. Of course, this was not the only loss involvedto city-tax-
payers for there is a considerable body of -city. land.that .4ies within the
Boundaries of the Everglades Drainage District, and drainage taxes of land
holders on these city lands helped to pay for the drainage program. Not to be
overlooked, but difficult to evaluate in cash, is the loss to citizens of
Greater Miami caused by the ruination of their private well supplies by salt
water. Hundreds, perhaps thousands, of private wells have been rendered
useless in a coastal strip averaging about 1V miles wide in Dade County; and
: in tongues extending inland along each of the tidal drainage canals well
supplies have been ruined as far inland as 5- miles from Biscayne Bay
S(as along the Miami Canal to a point west of LeJeune Road).
The United States Geological Survey has shown in their several
publications that our ground water supplies are being attacked by salt
water encroachment in two different but related ways:
(1) Up tidal drainage canals, at times many miles from the Bay, i -
and then leaking out through the sides and bottoms of the canals
to contaminate fresh ground water along the canals. It was this
type of encroachment that contaminated the Miami Springs-Hialesh
field in 1939 and that has since given trouble on several occasions,'
when, due to accident or inability to install a control dam in the
Miami Canal in time, salt water occupied the-stretch of the Miami
Canal adjacent to the present well field.
(2) By moving in from the Bay all along the shore line and
displacing freshwater in our huge underground reservoir.
It was this kind of encroachment that ruined the Spring Gardens
field, possibly aided by No. 1, and a combination of Nos. 1 and 2
that ruined the Coconut Grove field. ,
The United States Geological Survey geologists have measured our
aquifer. They find it to be a wedge-shaped mass of highly permeable rooks
with the thin edge of the wedge to the west. The highly permeable aquifer
is about 125 feet thick at the western shore of Eiscayne Bay, about 100 feet
thick at INW 20th Street and also in the vicinity of the well field, and
somewhat less than 40 feet at the Dade-Broward Levee. Quality of the water
in the aquifer is best under the coastal Ridge, with the best water of all
to the south in the Peters-Homestead area. Under this wedge of highly
: permeable rocks is a thick section of clays, bilts, and very fine sands in
which there is essentially no movement of water at all.
To control the movement .of salt water in the Miami area there are tvo things
that must be done: .
S (1) By the placement of barriers in the lower ends of tidal
canals to prevent the free passage of sea-water up these canals
Wvien conditions are favorable for it, to do so.
(2) Raise ground water levels high enough to build in effect a
Fresh water dam' ,Such a fresh water dam would of necessity
have to be under the Coastal Ridge, and asclose to the shore of
.Biscayne Bay as possible.
S, e depth of 100 feet to the relatively impermeable clays, silts
and sands that underly our highly permeable aquifer demands 2- feet of fresh
Sweater above m.s.l. Such a height of fresh water would have weight enough to
depress the encroaching sea water to the very bottom of the aquifer, and
fresh water would thus fill the'guifer from top td bottom, and prevent
S further inland movement of the salt water. The placing and proper operation
.of control works in the several tidal drainage canals of this area would
accomplish this objective. It would save the now-threatened city well field
indefinitely and would eventually; re-freshen and once more make usable wells
S in the area to the west of the controls. It would also reclaim some of the
aquifer downstream from the controls, through freshening of the shallower
portions of the aquifer.
It has already been stated b the United States Geological Survey
in one of their reports (Parker, G.G., Ferguson, G.E., and Love, S.K., Interim
Report on the Investigations of Water Resources in Southeastern Florida with
' :* special reference to the Miami Area in Dade County, Fla., Geol. Surv. Rep't. o0
Inv. No. 4, 1944, p. 33) that
..... C ... .. --..- .i-.li.-.., ..
"The farther downstream control structures could be placed
and operated in these (Miami, Tamiami, Little River,.Biscayne,
Snake, and Snapper Creek Canals) and connecting canals which
discharge into salt water, the more effective saltwater control
w would become, and the closer to the Bay encroaching saltwater
would be held'".
It seems needless to point out that although the present temporary
::, d': r in the Miami ',Canal near lW 36th Street Bridge has temporarily saved the"
'i. well field, it is too close to the cone of depression surrounding the well
field to be retained as the site of the permanent-structure. Monthly maps
of the well field area showing water table contours and isochlors have been
issued by the United States Geological Survey since 1939; these monthly maps
indicate that even with the dam in place salt water is still moving inland
at depth in the aquifer. This movement is very -slow, and because the United,
States Geological Survey scientists haven't had time to observe the movement
long enough to determine its rate of movement inland, the rate isn't exactly
known. To determine this, observations would have to be carried out over a
Period of years several times as long as the United States Geological Survey
Shas had already.
The Dade County Engineer Department has proposed a control works
Si the Miami Canal at 1W 20th Street. This is 4 miles downstream from the
well field, whereas the present site of the temporary dam at W 36th.Street
.'is only 2-3/8 miles downstream. The proposed 20th Street dam and locks site
would give the well field an additional s afety f actor of 1-6/8 miles of fresh
i:' 'water on the seaward side of the well field, and would give immeasurable
relief from salt water encroachment.
, ii I~
SThis 20th Street site has not only the advantage of removing the
salt water front downstream in the Miami Canal, but it would, prevent salt
water from finding access to the Tamiami Canal and thus from attacking the
well field on its southern and southeastern flanks, 20th Street is down-
stream from the confluence of the Miami and Tamiami Canals. The 20th Street
site would also prevent salt water from entering into and becoming trapped
in the deep rock pits known as Seminole and Palmer Lakes. These pits, or
lakes, are excavated to average depths of about 20 feet, but have lopal deep
spots of about 40:feet. Thus, their bottoms are deeper than the inlets
from the canals and once salt water finds its way in it does not flow back
out again. The salt water is heavier and denser than fresh water so'sinks
bottomward and seeps out through sides and bottoms of the lakes to contaminate
ground water on all sides. These lakes thus become local "arms of"the sea"
and are focal points of ground water contamination doing untold damage to
the fresh water.
Because of all these facts recited above, it is the sincere desire
of the City of Miami Board of Water and Sewers that a control works be placed
in the Miami Canal at NW 20th Street as planned by the Dade County Engineer
Department. This Miami Canal Control is a key point in the overall program
planned by the County to combat over-drainage; it would save the present well
field indefinitely; and it would reclaim a large part of the aquifer now
contaminated by salt water,: Of course, it may never reclaim all of the
aquifer already contaminated along the shoreline of Biscayne Bay, nor would
it restore ground water levels to their former heights, either in the Everglades
_ I ( i
or under the Coastal Ridge; neither would it of ittelf prevent
entirely the burning of dried out organic soils in the Everglades.
However, it would prevent further salt water encroachment and would
reclaim some parts of the aquifer now lost. It is the best answer
to the salt water encroachment problem that is possible, considering
the many factors bearing upon it.
Mr. Biter has already given you a general outline of
S the problem involved in checking salt water intrusion along the
Miami Canal, and the steps which Dade County proposes to take
in order to carry this program out effectively. We have been
working with and advising Dade County with respect to the
measures that should be taken and the type of :structure that
,::. should be built '. .- '
First of all, there is the general question as to
whether any control needs to be instituted along the Miami
Canal. :The best answer o this is that a considerable volume
and area in the ground water reservoir normally occupied by
fresh water in the vicinity of the Miami Canal and the Tamiami
Canal has to some degree been salted up. Clearly, this has
'been due to the very large channel vhich has been provided in
the Miami Canal. The effect of this canal is to provide a
salt water front on either bank of the canal very similar to
the salt water front on Biscayne Bay during the dry season of
the year, that is, foria period of some seven or eight
During this time, the concentrations of salt in the
Miami Canal are very large, approaching sea water. The effect
S.: : ^ '. 2
/ .' '
- -i r, -r i, . .- .i -.,, ,
July 9, 1946
STAEMEIT OF :BQDBgE T. KIAPPEN
Consulting Engineer for Dade County Water Control Program
at Hearing on Miami Canal Lock
S held by the U. S. Engineers
',July: 31, 1946
of this is to provide a zone on either side of the canal where
* a salt water front meets the fresh water and the canal serves
to drain off the fresh water.
Now with the Miami Canal coming close to the well
fields and the draft on the well fields during the dry season
reducing the volume in the fresh water reservoir, salt water
was drawn in to the well fields, first,s of. course, in very small
This led to the construction of a pneumatic dam above
the government channel at 36th Street, the purpose of which was
to hold the water above the dam at a higher elevation than the
water below the dam. This structure failed and was replaced
temporarily by a steel sheet pile dam which has been effective
in checking the salting up of the well fields.
In view of the experience already gained with the
structure at 36th. Street, first consideration was given to the ,,
construction of a lock structure at 36th Street and a. similar
one on the Tamiami Canal above its junction with the Miami
Canal. The idea vould be to hold: the water level at these
structures about 2~ feet above mean sea level. This would be
sufficient to more than balance the difference.in density
':between fresh and salt water and maintain this differential
except at times of extremely low flow, when the draft on the
well fields might prove to be great enough to lower the water .
table over a very considerable area. In any case, since during
,, this period, there is little replenishment of the ground water
table, the draft on the well fields creates a cone of depression.
Of course when this exists and when the salt water face is close
to the depression cone, there is a strong tendency to pull in
damaging amounts of salt water into the well field. In our
opinion, the location of the lock at 36th Street is so close to"
S- t -"the well field as to make the well field unsafe, and therefore
' .if protection is to be provided for this well field the salt
""'. w ater barrier' must be moved further downstream.,.
It will be desirable to move this look structure, out
as close to Biscayne Bay as possible. However, it would seem
to me a serious problem to put the lock in the mouth of the
Miami River for many reasons. The most practicable site for
t he lock was found to be at the site now proposed, whioh is
some thousand feet below the junction of the Tiamimi and Miami
;Canals. In our opinion, this location is sufficiently far down
S : :i: : to protect the well fields and to re-establish a considerable,
S area of fresh water storage between the structure and the well
fields over a period of time. We therefore feel justified in
recommending to Dade County that a barrier structure be placed
at this location. In our opinion, a structure at this location
; :" ... will be far enough down to protect the well fields and also
: will b effective in re-establishing a considerable amount of
Fresh water storage. We further believe that at this location.,
the well fields will be safe, against salt water intrusion, for
an indefinite period in the future.
: series of studies have teen conducted by Mr. Stephens,
S:, Water Control Engineer for Dade County, to develop economic
-.justification fOr the proposed work. These studies, which
' ::'will be presented to yu by him, show that the proposed
*'/ ', '
, "*.. .
'installation will provide benefits.greatly in excess of the
cost of the project. ..
The location selected.for.the salt. ater barrier
- lie's within the limits of the U. S. Government navigation ohan-
nel. Dade County, therefore, is asking for a permit to place
..this structure in the navigable channel. In order to.provide .
the'least possible. hrdship-to navigation, it is proposed to
construct two locks in connection with the carrier. Each one
of the ,locks would be.controlled' by a''gate upstream and.
S' downstream with a loc)c chamber between the gates.
The larger one of the .looks would have a depth of
15 feet below mean sea level, ihich dbpth is below,the bottom, -
of the navigation channel.which is- set at 15 feet below high .
water. The width of' the large lock .structure would be 40 feet "
and the -length of the chamber. between gate monoliths would be
320 feet. A studyopf the navigation moving in .the canal has:.
been ma'e,, and it was found that -.theidth 'of this look is.'
great enough to permit the passage of any.vessel or barge which
S navigates these waters. It is als.olong enough to takq the '
longest tows which were brou thrtb ough these nater wiit out . "
breakingthem up. . ,
S About 70 percent of the, boats passing this point ar
small boats, .less thO 60 fet';in length ad '18' feet in ith, .
and generally having- drafts of 5 or 6 feet br less. To prqvid '
for these vessels, an ailiaoy lock chamber 18 feet.by 60.feat
..he.. '4 -s
w' ith 7T feet of depth below mean sea level is 'provided. This
lock 1rill take all the small bot ffiO's at ordinary times, .
On holidays, when the small boat traffic is very heavy, it will
A: .be necessary occasionally to use the lare -ook to take 'hese '
,. .. .'., .' -, ..j -. .--' .'. ,. . .
'*^ '' 4; .''
a . .
St I .
444 .- >
* . A
Boats through. *
., t is not.intended'at this time to submit the detail.s.
Sof the proposed look construction for approval.- General plans
-only have been submittedd' However, it is proposed that the
lopk design *ill be uch as to. permit the movement of vessel,
and barges,through the structure with the least possible-delay.
It is-planned -'that.the gates will .operate from fully opened to
fully closed position in two minutes for the, large look and
. one and one-half- minutes for the small look. It is proposed
'that the'water will be equalized in'the look chambers in less
than two minutes'..' With .thip procedure, there should be very
little lbss of.time and therefore very little ddlayto traffic.
The delays have"been estimated by Mr. Stephens in his report
anid are believed to be quite conservative.
A navigation traffic count was made for the Months
of November 1945 through May 1946 inclusive at the location of
the proposed structure at NLW. 20th Street. A similar count
was made at the Tamiami Canal in N.W. South River Drive for
the Months of January, February and March 1946. The results
of these traffic studies are summarized in the following tables:
:r ;7 1
It will be seen from the foregoing that the average
S. monthly number of lookages for the main lock for commercial
vessels would be 222 per month and.for pleasure craft over 60
feet in length 86 per month, a total of 308 per month.
'Thse would largely move on week-days, so that the average
number per day would be approximately twielve. The maximum
:per day is approximately double this, or twenty-four. Fre-
.quently more than one vessel or two would pass through the
SIlook at at time. Based on an average time of 20 minutes per
lockage, the maximum demand could be handled in less than
eight hours, or one-third of the time. It would therefore
appear that the proposed main lock was of ample capacity to
take care of present and future traffic. The average number
.f lockages per month for pleasure craft under 60 feet in
S length is 652 and the maximum 924. This is an average number
of 20 to 30 per day. This number can be easily handled by
the small lock, particularly when it is considered that several
of these boats may pass throughthe lock at one time and also
that they may pass through the large lock along with commercial
vessels. On Saturdays, Sundays and holidays, the maximum
number of pleasure craft maybe 100 or more. On these days the
commercial business is light, and as many of the pleasure craft
.. as appear in excess of the capacity of the small boat lock can
be taken through the large boat lock in groups.
It may be seen from analyzing the foregoing data that
the proposed lock structure is-adequate in size and capacity to
S. .take care of the present traffic and any reasonable expectation
of future traffic.
It is proposed to design the gates so that they may
be removed for maintenance and repair with a minimum of delay
to traffic. Their design will be such that they can be removed
over-night for annual overhaul during the period when flows are
high enough in the main stream to make the use of the lock
i unnecessary. The dam structure itself will provide six 10-foot
Side flood-gates with protection against back pressure.
S: The type of gate selected is the bottom hinged gate
known also as the tumble gate. This has particular advantage
in the main lock when the lock is being used by shallow draft
vessels, as it will not be necessary to lower the gate all the
way down and thus the salt water flows which follow the bottom
of the channel can be' impeded.
; In times of flood flow, all the dam gates as well as
:,the lock gates, may be opened wide and it will then be possible
Sto pass the greatest possible flood that can come down this
channel at a comparatively low velocity. With a flow of 4,000
S .f.s., the velocity will be less than 3 feet per second.
SThis flow is greater than the greatest experienced flows.
The location of.this lock at the site proposed will
have a number of beneficial effects upon navigation. In the
first place, the effect of this barrier will be to stop the
movement of the tidal prism at that point. This means that
the tidal velocities below the barrier will be considerably
less, since the large amount of tidal flow required to fill
the basin above this site will then become unnecessary. The
result will be that the tidal velocities just below the lock
will be negligible, and will be considerably reduced from there
to the mouth of the Miami Canal. Above the dam, the tidal
fluctuation will be eliminated and there therefore will be no
Stidal velocity. The only currents will be those of the
drainage and flood waters. Above the lock there will be fresh
water 12 months in the year. This will make locations above
; the lock most desirable for anchorage. It will also permit
the opening up of Palmer Lake as a fresh water anchorage and
SThe effect of the locks also will be to provide a
.. .uniform stage in the canal upstream from the locks. This will
be advantageous for mooring and docking of vessels. It is
believed that the benefits to navigation will very largely
offset the cost of the delays involved. The other benefits
which will accrue from this project, that is those that come
from maintaining the fresh water underground reservoir, are,,
S. .. very great and far exceed the cost of the proposed project.
: : It might be pointed out at this time that the,
alternate sites considered for the water control structures
are abovehe navigable channels. Lock structures there re
Should not have to be as large as at the proposed location, or
if they were built as large, the cost of the installation
would be very great and there would be two lock sruotures to
be maintained and operated perpetually.
N ow it is entirely possible that the development of
,. Miami will make it advisable to extend 'the navigation channels
further inland and there is no reason why this should not be
done with adequate salt water barriers. The proposed location
of the lock below the junction of the two streams would be the .
most advantageous location once this future development is
accomplished, for navigation could come out; of the Tamiami
Canal and go up the Miami Canal without having to pass through
any locks, as against having to pass through two locks if the.
upper locations were selected.
You will hear from-a number of others at this Hearing,
who have been studying the problem of salt water intrusion
for many years. It is the consensus of opinion of these
experts that the look and dam structure for the purpose
of stopping salt water intrusion and maintaining fresh water
levels should be placed below the junction of the Miami and
:Tamiami Canals, and that the site selected and recommended at
this hearing is the farthest upstream that this structure
should be located to meet the situation effectively. It is
also the opinion of these experts that it is vital to this
community that this structure be installed.,
To sum up: .'
1. The proposed structure is necessary for the maintenance
of the fresh water reservoir upon which Miami depends for its
2. Tfe structure cannot be located further upstream and be
3. The structure will not prove to be. an unreasonable
ohstaole to navigation, but will in fact provide considerable
benefits to. navigation.
r. .. - r I I - ..)..-. --i .
4. It is therefore believed that the permit requested
y :" .: by Dade County for the construction of this structure should
S be granted, subject of course to final approval of detailed
plans by the War. Department.
K'A PPEI EIlGIMEERING COMPANY
By (Signed) Theodore T. Knappen
. .. :r .: : .. 1 '. ; ... ., w ...
July 2, 1946'
Col. A. B. Jones R e: Proposed Look in.Miami River at
District Engineer N.W. 27th Ave., Miami, Fla.
U. S. Engineer Office
. ,- :As a firm who is just completing a large investment on Tamiamin
SCanal west of Red Road (I .W. 57th Ave.) we wish to have our com-
ment vdth reference to the proposed lock in the Miami River at
N.W. 27th Ave. considered and entered in the record.
: We are completing a %500,000.00 stone cn.ishing plant, quarry,
Sand concrete block plant on the property lying between Tamiami
Canal on the south, Miami Air Depot on the north; FEC and SAL
Railways on the west, and Red Road on the east. We will trans-
port our products by barges down Tamiami Canal to Miami River,
through the proposed lock and thence to delivery points. We are
as vitally affected by the proposed lock as any operation could
After a detailed discussion with Mr. EarleM. Pader, Dade County
Engineer, as to the size of the look, depth of water, mechanical
operating time, etc., we are convinced that the lock will be a
slight inconvenience at most. We are further convinced that this
slight inconvenience cannot be compared to the tremendous good
the people of Dada County will receive from the proper control of
their water supply.
In conclusion, please understand that our firm is in favor of the
: proposed lock.
'(SGned)R. C. G 'illiams
R G. Williams
SF 7r P Lt
S MIAMI IRON AND METAL COMPANY
Office and Yards 2481 N.W. 32nd Ave.
M e Miami,'.Florida
SAKGW-3 800.61 (6618) .
Miami Harbor. .
Biscayne Bay, Floridda June 25, 1946
United States Engineers Office
.Attention: A. B. Jones,.Oolonel
This is in regard to the construction of a lock and water control
dam in'the Miami River as outlined in your notice of June 11, 1946.
Our principal business is salvage. We vwn a number of lots on
S.the Miami.'River above .the proposed site and wish to state that we
'- approte-of the -project providing that the lock will not interfere
with river traffic.
It is our understanding thet the locks will be 40' wide, 320' long
and 15' deep in which case that should not interfere with barging
operations but we are not familiar enough with locks to understand
whether or not they would'interfere with.same.
Our opinion is that there are many benefits to be derived from water
control which will enhance the value of our property on the river
front as well as be a benefit to agricultural and other community
interests. Certainly ye would not'Want to imperil the water conditions
We handle a considerable amount of barge material in barges that carry
from 150 to 400 tons and anything that we can do to help the city dut,
we will be glad to do, of course, .without jeopardizing our business.
SThe War Department of the United States Engineers Office of Water
Fronts certainly would know Whether or not this would obstruct freight
traffic .on the Miami River atd if it did not, there would be no
objection on our part.
Yours very truly
S. MIAMI IRON & METALS
S(signed) Meyer Schwartz
. *'. MS':JY Meyer Schwaktz
BELCHER OIL COMPANY
M::iami Florida '
July 9, 1946
1., '' ^ : ,' l 1,4 .:
Col. A. B. Jones "
United States Engineers
It is our understanding that the County is oDntemplating construc-
t ion of a dam in the Mismi River, the hearing for the issuance of
.a permit for this purpose to be held June 11, 1946., ,
It is our desire to go on record favoring this construction, as in
our opinion the protection of water supply of the city will be
: vitally affected as far as salt water intrusion is concerned unless
S.; ;some steps are taken, such as the construction of this dam to pre-
vent this salt water intrusion.
This company owns some river frontage above or west, of the loca-
tion of the contemplated salt water intrusion dam and while some
S, inconvenience may be caused by this contemplated construction it
is our considered opinion that the protection of this city's water
: .: supply is more important than any personal inconvenience that may
be suffered by those whose property is located west of this contem-
In view of the above circumstances, we recommend that the permit
.applied for by the County for this construction be granted.
Yours very truly,
'(Signed) C. B..Chinna
C. B. CHINN'
... -..... . .; .
,DEPARTiENUT OF TBE INTERIOR
P.O. Box 2529
Miami 15, Fla.
:July 5, 1946
The bDisbtrict Enineer,
. United States Engineer Department, '
Dear Sir: .
,The attached "Summary of conclusions reached after six years of investi-
S:gations of the geology and ground water of the Greater Miami Area,
Florida" has been prepared by the writer inresponse to a request
From the Dade County Engineer Department. 'The summary is intended"
to be used in connection with a public hearing to be held in Miami
by the United States Engineer Department on July I1, 1946, when the
subject of a control structure in the Miami Canal will be discussed.
The United States Geological Survey does not en er into this hearing
:.as a partisan. The data we have to submit is offered without prejudice
or bias, and is factual. It is based on somewhat more than six years
of intensive investigations of the geological and hydrological conditions
Controlling the occurrence of ground water in this area. The United States
Geological Survey has made these investigations in financial
cooperation with the Cities of Miami, 'Miami Beach, Coral Gables, the
County of Dade, and the Florida Geological Survey, the investigations
being part of a nation-wide program the aim of which is to learn the
facts of our Nation's ground water supplies.
Very truly yours,
(Signed) Garald G. Parker
Garald G. Parker
Geologist in Charge
Ground Water Investigations
Sin Southern Florida .
SUMLiARY OF CONCLUSIONS REACHED AFTER SIX YEARS OF INVESTIGATIONS
OF THE GEOLOGY AND GROUND WATER OF THE GREATER MIAMI AREA, FLORIDA
Garald G. Parker, U. S. Geological Survey
It is not believed necessary at this time to delve into the history:
of the water resources problems of the Greater Miami Area, nor to
describe in detail the work done by the U. S. Geological Survey in
cooperation with the Cities of Miami, Miami Beach, Coral Gables, the
County of Dade, and the Florida Geological Survey in studying these
problems. The data have already been presented in almost twenty
separate reports. O0f these, perhaps the ones that bear most on the
problem of water control are the following:
(1) Parker, G. G., Ferguson, G.E., and Love, S.Ki.: Interim report
on the water resources of southeastern Florida with special
reference to the Miami Area in Dade County, Rep't of Investigations' :
ITo. 4, Florida Geological Survey, 1944.
(2) Brown, R. H., and Parker, G.G. : Salt water encroachment in lime-:
stone at Silver Bluff, Miami, Florida, Economic Geology, Vol. XL,
No. 4, 1945, pp. 235-262.
(3) ;.Parker, G. G.: Salt water encroachment in southern Florida, American
1ater Works Association Journal, Vo. 37, IIo. 6, 1945, pp. 526-542.
(4) Gross,'W. P., Love, S.E., Parker, G. G., and Wallace, D.S., Progress
report on the water resources investigations in southeastern
Florida, mimeographed, in two volumes. Text in Vol. 1,
illustrations in Vol. 2, 1940.
(5) Parker, G. G., Late cenozoic geology of southern Florida with a
discussion of the ground water, Florida Geological Survey Bull.
,Io. 27, 1944.
Copies of Nos. 1,2 3 and 5 listed above are attached herewith for ref-
erence. No. 4 is out of print, though a copy is available at the Miami,
Ocala and Washington, D.C. offices of the U. S. Geological Survey, and
each cooperating official has one copy.
Although there are many conclusions that have been reached as a result of
the geological and hydrological studies made by the U. S. Geological Survey
in this area, the minor ones need not be recited here. Only those of major
import will be considered.
(1) Prior to drainage development in southern Floida there was no problem
of salt water encraochment.
(2) Prior to 1942 (between the beginning of the encroachment and Feb. 4, 1942)
- salt water had been moving inland at depth in the fresh water aquifer
at a rate of approximately 235 feet per year.
1 '; 1......-...~:'.i -5. -..., ..c-. j i ~~~r r I ,
'(: ;:i ( '):( '.l'''i:;,. C,) 1 I .I, ... '
(3) Between Feb. 4, 1942 and Oct. 28, 1944 salt water moved inland
at depth in the aquifer at an average rate of approximately 890
S feet per year.
(4) The 890 feet per year rate occurred during the drouth of 1943-44
and is probably not the yearly rate at which salt water will
continue to encreaoh. There are definite indications that under
conditions of heavy rainfall and high water tables the salt en-
croachment is not only slowed down but in places moves seaward. lhe
overall trend, however, is for the salt water to move inland,
(5) Salt water moving at depth in the aquifer is behaving according to
laws of physics, and responds to increases or decreases in the
weight of freshwater above mean sea level by moving seaward or land-
ward. When water levels fall salt moves inland; when they rise high
enough it stops or even moves seaward.
(6) ): Drainage has so lowered the weight of freshwater above mean sea
level in the Miami area that the long established equilibrium between
salt and fresh water has been upset, and under the laws of physics
the salt water is gradually moving inland seeking a balance under the
Snew conditions. .. '
(7) Geological conditions are such that the aquifer in the Miami area is
very highly permeable. Furthermore, the'aquifer is underlain by
about 400 to 600 feet of relatively impermeable materials which
prevent the easy movement of water through them. These geological
conditions permit the natural development of a great underground
storage reservoir sealed off from waters below, but open to water
above and on the sides.
S Th aquifer is wedge-shaped, thick toward the shore and thin toward
Sthe interior of the Florida peninsula. Along Biscayne Bay it will
average some-Lhat more than one hundred and twenty-five feet in thick-
ness; in western Miami it is about one hundred feet thick; forty miles
: west it is only about ten feet thick. To the south it becomes shallow-
er, being only about sixty feet thick in the Homestead-Florida City
area, but it is very highly permeable. To the north of Miami the
aquifer extends somewhat beyond Delray Beach, but becomes sandier and
sandier to the north. ,
In the Everglades and to the north of Detray under the Atlantic
Coastal Ridge the aquifer interfingers with or grades into the
Caloosahatchee marl, a material of relatively low permeability. Very
little ground water makes its way out of the Caloosahatchee marl into
:' the principal aquifer of this area.:
(8) The amount of water taken from the present well field (from thirty to
: forty million gallons a day) is only a very small amount of water as
compared to the large amount available.
.i'.l -: -1:. .--.-
(9) The effect of the well field does not ever extend over a very
great distance -- the radius of the cone of depression is seldom
|' over a mile.
(10) Because of the geological controls, the water supply of the Greater
Miami area, which is taken from the huge underground reservoir
above described, is almost entirely derived from local rainfall.
Very little water is carried into the aquifer from areas outside the
boundaries of the aquifer.
(11) Because of the controls over salt water encroachment exerted by the
laws of physics and geology, it has been determined that salt water
in the :.liamid area will come eventually to rest in equilibrium with
fresh water at the place where the tio and one-half foot average
annual contour on the water table exists.
The salt water is denser and has a greater weight than freshwater,
so much so that a forty foot column of salt water weighs the same
as a forty-one fbot column bf fresh-water. This gives rise to the
Ghyben-Herzberg Principle used by geologists and engineers in de-
termining the depth to salt water in a coastal zone of permeable
materials where salt and freshwater come into contact. Simply, the
Principle means that for each foot of fresh water that exists above
mean sea level at the zone of contact there will be an additional
forty feet of fresh water below
(12) Since the aquifer here is one hundred feet thick, and it is desired
to have it completely filled with fresh water from top to bottom thus
leaving no room for salt water at all, it is necessary to have t.o and
one-half feet of fresh water above mean sea level (2| x 40 = 100) to
(13) The maintenance of ground water levels at an average yearly stage of
two and one-half feet above mean-sea level can only be effected by
Controlling the canals which drain Dade County, and the.greatest de-
S gree of control that can be effected probably will not prevent some
further inland movement of the salt water in the aquifer; however, it
would preserve a substantially large area that otherwise would be lost
to encroaching salt water, and it would reclaim some parts of the
aquifer now salted, especially those parts extending inland several
miles along the tidal canals from the main body of salt water contamina-
(14) The father downstream control structures could be placed and operated
in tidal drainage canals in Dade County, the more effective water
control would become, and the closer to the Bay the encroaching salt
water would be held.
(15) The temporary dams that have been in operation in the Miami Canal
-at N.W. 36th St. are all that'has saved the present well field
.of the City of Miami and all the private wells that exist in the
/ Hialeah-Miami Springs area to the west of the dam along the Canal.
SHowever, these dams have not been wholly effective for none of them
(" has actually stopped the westward creep of the salt water at depth
S in the aquifer. This is shown by a study of the monthly maps of the
SMiami well field area,-prepared by the Miami office of the United
SStates Geological Survey. These dams have not stopped salt water
encroachment at depth in the aquifer because they were not designed
: to raise the water table behind them. Their function was to prevent
the movement of salt water in the canal upstream from the dams.
The: several dams that have been installed at the 36th St. site have
prevented, to a large extent, the salt water from finding free access
to the stretch of the Canal adjacent to the well field, but on occasion
when the dam has been out of place or broken salt water has penetrated
inland adjacent to the well field in the Canal. This has brought about
local and small scale saltings of the areas adjacent to the canal, and
at the present time some of that salty ground water is present adjacent
to the well field.
(16) The development and putting into service of five new wells in the
i "upper field", and cutting down of pumpage in the old "lower field" has
S... ..caused the cone of depression around the i.ell field to change location.
It has moved about one mile north and 0.7 mile farther from the front
of the tongue of salty ground water headed toward the well.field and
now situated (the front of high chloride, 500 parts per million or more)
:.. ,. about 0.7 mile INorthwest of 1.W7. 36th St. Bridge. This temporarily
makes the field safer, because salt water now will have a greater dis-
tance-to travel tb gain access to the wells.
However, .for the safety of the well field, this change of position of
Sthe cone of depression still leaves the outer edge of the cone too near
the tongue of salt water mentioned above. If the well field is to be
saved it will be necessary to have the control located much farther down-
stream than 36th St. preferably below the mouth of the Tamiami Canal.
If this were done, the area between the well field cone of depression
and the dam would be increased by whatever distance the control were
Smoved.- Properly controlled so that only fresh water ever occupied the
.stretch of canals abovethe controll works, the well field should be
safe for years to come. .
(17) If it should not be deemed essential to save the present well field
and all the private wells along the Miami Canal, the loss involved
: would be mainly an economic loss. The aquifer is large enough and pro-
S. / ductive enourJs that numerous \Lell .fields of the capacity of the present
. one could be developed within thirty miles to the south, fifty miles to
: the north, and fifteen to eighteen tidles to the west (of downtomi Miami).
(18), It would not be possible to develop large supplies of ground water in
Sthe Everglades more than fifteen to eighteen miles west of the coastline.
This is due to the thinning of the aquifer and consequent lesser capacity,
to the increasing amounts of sand that reduce the permeability,
and to the increasing poor quality of the water with distance away from
IL .. the coast.
HU/t. '& T RS
SSTATENET BY COMI ISSIONERITB PETERS
AT U. S. ENGINEER HEARING ON
PROPOSED MIAMI RIVER LOCKS .
July 11, 1946
S My name is Hugh Peters. I am Vice-Chairman of the Board of
County Commissioners of Dade County, Florida and represent said Board
in the absence of the chairman who is out of the city.. The Board of
County Commissioners of Dade County, Florida, has been charged by the
1945 Legislature of the State of Florida with the responsibility for
the water control program of Dade County. ;
This authorization came as a result of extensive studies made
by Federal and State Agencies and widespread local agitation based upon
the very real need for ending the intrusion of salt water into many areas
in Dade County which have previously been underlaid by freshwater.
It was apparent to this community that the intrusion of salt
water was causing a large amount of damage and was threatening us with
even greater damage in the future. We found that our freshwater supply
for the City of Miami and other communities was threatened, that .many of,
our agricultural lands were being rendered unfit for cultivation by salt
deposits, that our fresh water anchorages for small craft were being
largely eliminated and that the reduction in fresh water level which
went along with this problem was contributing to the rapid destruction
of our peat soils.
Under the authorization given to Dade County, the County has
started a program of water control which has included placing a number of
_ 1 / j_ __
temporary and permanent dams in various streams, water courses and
drainage canals leading into Biscayne Bay. As a result of these measures
a considerable improvement has already taken place in many areas. This
work has been under the direction of County Engineer Earle M. Rader: and
his assistant, the County Water Control Engineer, John C. Stephens. The
County has also retained the Knappen Engineering Company as consulting
engineers on this project, and Mr. Knappen and Mr. Tippets of this firm
have worked with Messrs. Rader and Stephens in developing a water control
The most important unit of this program is the proposed locks
and dam structure in the Miami River. We have already submitted to you,
a request for a permit to build this structure, and this hearing, as I
understand it, is called in order that you may receive testimony on this
request for a permit. The County Commissioners would like to emphasize
the great importance which they attach to this proposed construction, and
ask that you give the matter yAur early attention, and further ask that you
grant us the right to build the proposed structure.
I shall now ask County Engineer Earle IA. Reader to present this
matter in more detail to you.
/ LI Nn'.5
^r~~~I r-r' True
IMALCOLM PIRNIE ENGINEERS
New York 18, N. Y.
S;: .STATEMENT OF
MALCOLM PIRlIIE, CONSULTING ENGINEER
.'DEPARTMETrT OF WATER AID SEWERS, CITY OF MIAMI
U D WAR DEPARTMENT
i: cUN.. UITED STATES ENGINEER OFFICE
ON APPLICATION OF
TO CONSTRUCT A WATER CONTROL DAM WITH LOCKS
IN THE MIAMI CANAL
APPROXIMATELY 275 FEET UPSTREAM
: F FROM WESTERLY SIDE OF N. W. TWENTY-SEVENTH AVENUE
DADE COUNTY COURT HOUSE, MIAMI, FLA.
THURSDAY, 11 JULY 1946
MALCOLM2 PERNIE ETIGINEERS
Uew York 18, N. Y.
July 6, 1946
United States Engineer Office
As consulting engineer for the Miami Water Company and
at various times for the City of Miami Beach since 1920,
the Jacksonville Vater Supply Commission in 1927, War Depart-
ment as a member of the Board of Engineers and Geologists
ihich reported on Ground Water related to the Atlantic-Gulf
Ship Canal and now for the Department of Water and Sewers,
City of Miami, I have been actively engaged in studies of
ground and surface water resources of Florida, especially
those within Dade County, for more than twenty-five years.
The attached brief statement for the record of the
11 July 1946 hearing on the petition of Dade County for permit
to control water levels in the Miami Canal is respectfully
submitted at the request of the Department of Water and Sewers,
City of Miami.
Very truly yours
(Signed) Malcolm Pirnie
Ground Water Reservoir in Dade County
Immediate Need for Protective Water Level Controls
with particular reference to
Miami-and Tamiami Canals
Immediately under a strip of land, approximately
twenty miles wide east of Biscayne Bay shore line (Exhibit 1
blue and red areas) there exists a wedge shaped mass of very .'
porous rocks, thin along the westerly edge and slightly more
than one hundred feet thick along the Bay shore. The surface
materials are-shallow deposits of sand generally exposed on the
higher lands with a muck covering on the lower lands. This
porous mass lies on top of a -rradobially impervious formation
several hundred feet thick ifiich acts as an effective seal between
the younger porous rocks above and the older porous rocks below.
(Exhibits 2, 3 and 4.)
A large proportion of the rainfall on the surface of
this porous wedge percolates vertically to the underlying ground
water raising its surface above sea level. This creates head: re-
quired to cause slow easterly flow of fresh water to escape into
sea water near the shore of Biscayne Bay. Hbre the fresh-water
meets the movable sea water east wall of the ground water re-
servoir (Exhibits 3 and 4) flowing upward from the bottom and lower
depths in the reservoir in the contact zone between fresh water
and the west face of the movable sea-water wall. At the west face
and over the crest of the movable wall, sea-water is depressed
forty units below sea level for each unit of fresh water head
above sea level. The fresh-water carrying varying mixtures with
sea-water discharges through the porous Bay bottom close to sea
level in a variable zone or band automatically adjusted in width
to permit the existing volume of fresh water flow to escape.
Natural and artificial channels cut through the Bay
shore ridge move the fresh-water escape band inland. In these
circumstances high ground water levels resulting from heavy rains
must flow laterally.for considerable distances through porous
rocks to discharge through the limited perimeters of the channels
until the crest of the movable sea-water east wall of the ground
water reservoir can be forced eastward through the porous rocks
tb reestablish an adjustable escape band in the. Bay bottom along
the shore line. Obviously the existence of a moderate number of
such channels causes substantially higher ground water levels
during periods of heavy rains than would occur if the adjustable
crest of the movable sea-water east wall of the reservoir were
maintained at the shore line of the Bay.
TWhile channels cut through the Bay shore ridge cause
increased ground water levels in wet periods they also cause
substantially lower ground water.levels in extended droughts.
With little or no recharge from rainfall and continuous drainage
of fresh water stored in the rocks above sea level the storage
is depleted month by month and the fresh water pressure against
the movable east wall of the reservoir is reduced. This wall
moves westward seeking a pressure balance. Rate of movement is
limited by friction of flow of salt-water westward and of dis-
placed fresh water seeking escape to sea level through the sides
and bottoms of the channels.
Channels of substantial width ant moderate depth be-
come tidal surge ways in dry seasons when fresh water flows
are small. Flood tides project a wedge of sea-water surging in-
land on the bottom. The displaced fresh water flows over the sea-
water wedge in the opposite direction as its level is raised. This
causes considerable mixing at the interface and some back flow of
salted water into the surface waters of the ground water reservoir
until solid matter clogs the open pores in the channel sides and
bottom. Ebb tides withdraw the sea-water wedge followed by the
backed up fresh and salted water mixture. As the level falls
past mean sea level to approach low tide level ground water dis-
charge from higher elevations is resumed. This forces the solid
matter away from the pores to permit flow into the channel. The
*ground water drainage effect is similar to that of a tidal basin
controlled by check valves closedagainst flood tides and opened
to discharge on ebb .tides. The resulting; depletion of ground
water storage augmented slightly by pumping from wells had, on
May 19, 1945, reduced its surface elevation close to and even
below mean sea level over substantial areas at Miami Springs and
from Perrine to Royal Palm State Park.
Effective Adjustment of Crest of
Solvable Sea-Water East Wall of Reservoir
Restricting Fresh-Water Discharge during Droughts
Water table contours (Exhibit 5) record the steepest
slopes for easterly flows from the ground water highs immediately
north and south of the Hiiami Canal under the Bay shore ridge.
Depth of fresh water above the sea-water crest of the east wall
of the reservoir may have then been reduced to one percent or
less of the depth of freshwater to the west of the wall. Thus
the greater part of flow from ground water storage above sea
level at that time was westerly toward seepage discharges to
canals and the cone of depression caused by pumping water from
Miami .Springs well field. The area colored yellow is that under
which movement of ground water was toward Nuanu Springs and the
blue arrows indicate the directions of converging flows.
Westward Advance of the
Movable Sea-Water East Wall of Reservoir
From its natural location approximating Biscayne Bay
shore line the west face zone of mixing of the movable sea-water
east wall of the ground water reservoir has moved inland under
the area colored red (Exhibit i).' Salients of the advance are
established under the numerous tidal drainage canals of which the
Miami Canal is obviously the most menacing. Existing "improve-
ments" of this canal, solely in the interests of tide water
shipping, have doomed to bi-section this essential ground water
reservoir of Dade and Broward counties. Each successive "improve-
ment" of the Miami Canal has accelerated the northwesterly maroh
of sea water under it.
Miami's original water supply was from flowing wells on
the Miami Country Club grounds nearS..W. Tenth Avenue and a
natural water fall in the Miami River. The pure, good quality.
water flowed by gravity in a pipe line laid in the river valley
to the electric power station where it was pumped without treat-
ment into the distribution system. The initial Miami Canal con-
verted the Miami River and falls into a tidal section but con-
structed two small boat locks upstream forming the second pool
level above high tide near Miami Springs. -
The wells stopped flowing and pumps were installed to
lift water from them to the receiving basin for continued gravity
flow to the power station. Salt water contamination of the well
water started at the time of the first World War and Mr. H. H.
Hyman, then manager of the Miami Water Company, was sent to jail
for serving the people water containing salt in concentrations of
only about 200 PPH as Cl. For a few years salt-free water was.
obtained from wells drilled at increasing distances north of the
canal. In the year 1924 it was determined to establish a new
ground water production area above the second locks near Hialeah.
A legislative bill to permit use and maintenance of the new
source of supply was vetoed by the governor and the City of
Miami assumed responsibility for development and operation of
the source of water supply.
Almost.immediately the Miami Canal was deepened and
extended as.a tidal channel to Pensuco. The resulting sea-water
salient is still on its westward march. A concentration of one-
sixth sea-water has already reached N. W. 36th Street. From this
location, in spite of intermittent use of temporary dams, tongues
of sea-water contaminated ground water have already lashed north-
westward into the Miami Springs well field at times of low ground
water levels as recorded on February 29, 1944. (Exhibit 6).
On the bottom of the ground water reservoir the sea-
water intruder is always present with his rear supported by occupa-
tion of the volume of the reservoir already conquered, and the re-
suiting resistance to retreat offered by increasing distances for
sea-water flow eastward through the porous rocks. When pressure of
the fresh water wanes to less than that required to balance sea-
water at reservoir bottom elevation the intruder creeps forward un-
til balance of pressure is again established.
*Tt'su the proportion of the total time during which cer-
tain fresh water control levels are maintained is the most important
factor in permitting advance or causing retreat of the sea-water
: intruder. For example, if the fresh water level in the Miami and
Tamiami Canals is controlled as low as elevation 1.5 for more than
half the total time ultimate heavy salting of the existing Miami
S Springs Well field may be anticipated. (Exhibit 7).
S Most Effective Controls Possible to
Recapture and Preserve Fresh Ground Water Resource
Fortunately the bottom of the reservoir slopes downward
from its shallow westerly edge, generally with increasing slopes,
until it reaches its location under the Bay Ridge. Dams should
be constructed as close as possible to the Bay shore, high enough
to hold back the maximum flood tides, where all channels out through
the ridge and fresh water level controlled by the dams at or close
to rean high tide level for as great a proportion of the total time
ab -p'ssible. The movable sea-water east wall of the reservoir would
Then be gradually forced back to its natural position with crest
close to the Bay shore line. In these circumstances practically full
a depth of the reservoir would be available for lateral flow of ex-
cess volumes of fresh-water seeking discharge over the sea-water
crest into the Bay. The sea-water salients surrounding the tidal '
sections of the canals and obstructing flow of fresh water over'" ."
them to discharge into the canals would be rapidly depressed. Ihis
would increase effectiveness of existing canals for fresh ground
.; : water withdrawal when heavy rains cause relatively high levels.
With canal sections adequate for the drainage required,
ground water levels can be controlled within desired limits much
more effectively than is possible under present conditions. Higher
level storage should be provided in the shallower half of the ground
water reservoir by secondary controls in all connecting drainage
Channels. Such storage will extend the time when it is possible to
hold canal water levels at elevation 2.5 and may need to be sup-
S-: *' plemented by Lake Okeechobee storage drawn at times through connect-
SThis plan of control was included in the 1940 proposal
: for development of a source of ground water supply near the Brovward
County Line for Miami Beach. It included double controls in Bis-
cayne and Snake Creak Canals and reinstatement of effective control
at the locks in Iorth Hew River and South New River Canals in.
:;. .. :Brorard County.
Essential Need for Conservation
Sof All Sources of Satisfactory Water
SSouth of Latitude of North Shore of Lake Okeechobee
Very low land levels, correspondingly great distances
to the Atlantic and Gulf coasts and lack of porous rocks near
sea level in which an underground lateral drainage system could
develop have confined highly mineralized conate waters under
most of the land area. Fresh waters from the rainfall naturally
spread out and flow in shallow broad depressions to discharge
their unevaporated surplus as surface water flows to the ocean
and gulf. Canals dredged through the area which draw water below
natural surface levels now drain to them some of these conate
waters which cause marked depreciation in quality, during dry
weather flows. (Exhibit 8).
Dry season evaporation from Lake Okeechobee removes
water at a rate in excess of 2,000 c.f.s. and the shallow storage
remaining is definitely limited to provide large quantities of
water fbr various uses during periods of extended droughts.
Narrow belts of porous rocks meeting the oceanwater at
and near sea level provide substantial capacity for lateral flow of
Water in the pores to escape near the shore line. Such washing of
the rocks has dissolved their more soluble substances and has dis-
.charged the solutions and conate waters into the ocean. (Exhibit
; 8 Blue Area). This type of cleansed ground water storage reservoir
S was available under the area colored blue on the southerly east.
coast of Florida. One large reservoir extended south from Lake
Worth and another smaller one north from Jupiter Inlet. Both have
been substantially depleted in capacity by surface drainage opera-
The full capacities of these reservoirs are needed as the
only available covered storage basins in which fresh water from
the rainfall can be collected and held for use during many months
with few if any rains. The bulk of the fresh water stored in the
reservoirs is needed from at least 2.5 feet above sea level to the
bottom to hold their sea-water east walls at the shore line.
S Storage available fogi.water suqply, irrigation and leakage through
the east walls is only that volume above elevation 2.5. There is
no loss by evaporation from the reservoir surfaces over the
greater parts of their areas where the water table is below the
reach of capillarity and roots of growing plants.
The relatively low land covering of the reservoirs limits
the depths of storage available for use. This is no greater than
S;needed to support the population and activities which will be
established in this Florida east coast area within a reasonable
future period of time if the present trend in growth continues.
It would be a crime to permit the fortunes and industryoof so
Large a group of citizens to be invested in the area unless
I I I I I I I
III~ 9. I b I I I I
adequate steps are taken immediately to reestablish and protect
these natural ground water storage reservoirs.
Ship and Boat Looks at Sea Water Contact
Designed and Operated to Keep Canal Water Fresh
Model tests recently completed by Army Engineers at
Vicksburg, Miss. have demonstrated the feasibility of design and
operation of looks to prevent serious salting of canal waters. In
the sea level chambers when the sea gate is closed at least a half
lock full of fresh water is admitted at the surface ihile an equal
quantity of salt water is withdrawn evenly over the bottom. The
water in the sea level chamber is practically fresh when the canal
gate is opened. Water from an upstream sump in the canal bottom
is also withdrawn to discharge salted water which may pass over the
canal bottom sill. This is an essential use of available fresh
water supply. Water for this purpose in the Miami Canal might be
furnished in part through canals connecting with Lake Okeeohobee,
N. W. Twentieth Street Location
for Miami Canal Look
Location of the proposed lock at the temporary dam site
near N. W. Thirty-Sixth Street would not provide the necessary
factor of safety to prevent ultimate salting of the Miami Springs well/
field even with another lock built on the Tamiami Canal close to
its connection with the Miami Canal. Furthermore,mater levels
above both locks would have to be controlled at or above elevation
2.5 at all times. *
It is obviously preferable as a means of preventing sea-
water contamination of the well field at Miami Springs to adoptthe
recommended location near N. W. Twentieth Street as petitioned by
Dade County. At this location also water level above the lock should be
controlled at elevation 2.5 except when heavy rains cause such large
volume of flow as to require full look openings to effect its dis-
charge. : .,
If this II. W. Twentieth Street location is the nearest to :
the Bay shore which can be approved at this time it should be
authorized at once and built immediately. It will be useful as a'
second level lock when the Bay shore self-flushing look is built as
it should be in the immediate future.
Acknowledgments .':, .
This statement would not have been possible without the
splendid recordings of the excellent studies made by the United
States Geological Survey during the past six years. All of the
attached exhibits are copies of a few selected records of this
great work. They have been colored to emphasize the brief descrip-
tions presented. Discussions of controlling principles of the prob-
lem with Mr. Parker and Mr. Bogart have aided materially in
visualizing the operations of these coastal ground water reservoirs.
Inspections and consultations with t he'engineers of
the United States Department of Agriculture, Soil Conserva-
tion Service have contributed greatly to a growing understanding
of the over-all problem of desperately needed water control in
1111 11 I II I I ., I _
rJi & SL
ARLE At- /f9
STATEMENT OF COUNTY ENGINEER EARLE M. READER
AT THE U. S. ENGINEER HEARING
ON TEE PROPOSED MIAMI CANAL LOCK
July 11, 1946
My name is Earle M. Rader. I am County Engineer for Dade
County, Florida and as such am in charge of Dade County's Water Control
In general the water control program being carried out by Dade
County has as its objectives the stopping of salt water intrusion into
the fresh water, and where possible, the re-establishment of freshwater
in areas that have gone salt, together with the control of the fresh water
table in farm lands so as to make such lands more suitable for farming.
In the case of peat soils we propose to prevent their burning and reduce
their oxidization and thereby preserve such peat soils.
As Commissioner Peters has outlined, preliminary to taking the
action we are now taking, the U. S. Geological Survey in cooperation with
Dade County, has carried on an extensive study of the water control pro-
blem in this county. The U. S. Department of Agriculture, the Florida
Experimental Station, U. S. Weather Bureau, the Everglades Drainage District
and numerous other agencies (local, state and Federal) have cooperated.
This investigation revealed a serious salt water encroachment up
the streams and canals and particularly up the Miami Canal where this en-
creachment affects the city of Miami water supply well fields. As a result
of this investigation it was deemed essential to take positive action to
correct the situation; the County was organized as a water control dis-
trict and I set up, under my direction, a staff for that specific purpose,
) headed by John C. Stephens, Water Control Engineer, who will be heard
.. The investigations, engineering surveys and economic'surveys
S that we have made show that a series of control structures across the
drainage outlets to Biscayne Bay are necessary to hold the fresh water
table up to the desired elevation and to prevent the intrusion of salt
water during periods of drought. In non-navigable streams bulkhead dams
with gate controls are adequate for *his purpose and work on their planning
and installation is proceeding. Already excellent results havebeen ob-
tained in local areas from this program.
The Miami Canal which is a navigable channel at the preset
time is the largest channel which permits salt water to intrude into the
normal fresh water area.:, This channel has been artificially enlarged,
S (first, for drainage and second, for navigation,) to the point where the
salt water prism in said channel has become a serious menace to the city
of Miami well fields and to the agricultural and industrial development in
: the proximity of its banks. :
Prior to the dredging of this channel for navigation purposes by
the U. S. Government there were control gates near the" location of the pro-
posed locks in the channel to prevent salt intrusion and to control the
water table in the area to th th norwest. The map (Exhibit 1) shows the
location of the Miami Canal, the Tamiami Canal and the city of Miami well
fields. It also shows the limits of salt water intrusion as reckoned by ,
a'salt content of 1,000 p.p.m. as of February 1946. On this map the cone
of depression for the city of Miami well fields as it existed in February
1946 is shown. It will be noted from this map that the 1,000 p.p.m. isochlor
has already reached very close to said cone of depression.
S .'Some years ago the city of Miami installed a pneumatic dam
near N.W. 36th St. in the Miami Canal and this barrier which was not
: entirely satisfactory in stopping the salt water encroachment failed
structurally after several years of, operation. At the present time Dade
County has a steel sheet piling dam across the canal at this location as
a temporary expedient to give immediate protection to the well fields and
to agricultural lands.
'At the present time in periods of low flow a high degree of
salinity is evident in the waters of Miami Canal and the Tamiami Canal for
very considerable distances up these waterways. Without any control and
with increased population and water use, it is to be expected that the
s salinity would continue to encroach in ever increasing degrees upon urban
: and agricultural lands in the vicinity of these channels. Some form of
: control becomes absolutely necessary if very great losses are to be avoided.
The temporary control at N.W. 36th St. for the moment is doing a part way
Sjob of protecting the well fields where the city of Miami has an investment
,that would require from 2 to 3 million dollars to satisfactorily replace.
It is important not only to protect that investment but it is also
important to protect that well field basin as it is the best possible source
of fresh water in northwest Dade County.
We have reached the conclusion that our water control structure
for the protection of the maximum area against salt encroachment should be
placed as far down stream on the Miami Canal as is practical. The most
:practical site that we have found is the one lying between the N.W. 27th
Ave. bridge and the junction of the Tamiami Canal with the Miami Canal.
The site selected is far enough above the bridge to permit traffic to
enter the look and far enough beloa the junction of the canals to permit
_ 1 ,_ _I ~) II~ I _ __~
" I Irr.- .ILri.
Stows to come dovn one canal and go up the other without having to use-
the locks or to interfere with their operation. In connection with this
installt~on it will be necessary also to install control works in the
Comfort Canal. However, since this is not a navigable waterway these
works do not enter into the request for this permit.
There is no satisfactory site downstream where it would be. ,
practical to make this installation. Upstream from the proposed site a
double installation would have to be made, one on the Tamiami Canal and
the other on the Miami Canal. The only other location to be considered
SO;the Miami Canal above the forks, is at the location of the temporary
dam near N.W. 36th Street and a companion installation on the Taamia
Canal a short distance above its junction with the Uiami Canal would have
. to be built if that location were picked so as to complete the barrier.
re''.. 'i no po s as to, complete: t .,: '
Such a double installation would afford no protection from salt intrusion
S through the deep waters of Palmer Lake. :'
Had we selected said two upper locations we would nbot be asking
you for a permit inasmuch as these locations are not on waters recognized
S/as navigable by the U. S. Engineer Department. However, we still would
have found it necessary toinstall locks at both of these locations so as
to serve existing local navigation.' ,
After giving the matter very careful consideration and studying
the overall economics of the problem we have reached the conclusion that
the proper location is at N.W. 20th St. We have, therefore, filed with,
you an application for a permit to install a control structure at that
point. In making this decision we are guided by the relative, value of
Sthe proposed installations. The paramount consideration, however, is the
protection of the city of Mijami well fields and the protection to :
agricultural lands.: Our examination of the problem convinces us that
a permanent installation at I.W. 36th St. would not provide proper pro-
tection for the city of Miami well fields and that with this location the
city of Miami would have to plan to abandon said fields. On the other
hand, with the location of the structure at N.W. 20th St. we are satisfied
that the well fields will have positive protection.
We are also convinced that the location of the structure at
N.W. 20th St. will result in making fresh.again a large area of land in
the vicinity of these canals and will gradually push the general front of
salt water intrusion back toward Biscayne Bay. '
the overall economics indicate a very large advantage in favor of
the lover location. This will be treated in more detail by Mr. Stephens
in his report. However, I should like to point out that for the recommended
lower location for the lock the first cost to the County is considerably
lower, the city of Miami will be saved an expenditure of from 2 to 3 million
dollars for the moving of the water supply well fields and also will be':.
saved an increased expense for the treatment of water amounting to approxi-
mately $36,500 per year. We found that there will be great economies to the
present water users in the area where the underlying water will be made
fresh, and a further economy to prospective,developments of this area. *
WVe found that there will be very considerable advantages for fresh water
anchorage. It therefore appears that there will be a saving of close
to 2o,00 000 a year by the proposed installation which will be offset by
possible increased costs to navigation in the.neighborhood of from $10,000
to 012,000 per year.
Before determining the characteristics of the structure to be
_ (~~II()( i i
Installed a study was made of the types and number of boats which
would have to pass the proposed look location at :W. 20th St. As
a result of this study it was found that about 70% of the blockages
would be made by boats Iless than 60 ft. in length and less than 18 ft.
in width, having drafts of less than 6 ft. It was therefore decided to
install two locks, one to take care of the large boats and tows and the
second to .take care of the smaller boats.
The large boat look will have a look chamber 40 ft. wide by
S320 ft. long with its sill approximately 15 ft. below mean low water. "
:: ,This is believed to be amply: large to take care of any vessels that are
now using this waterway or that are likely to use it in the reasonable
future.. Consideration was given to making the width 50 ft. in view of
the fact that some other locks in Florida are 50 ft. wide but as no justi-
fication was found in the traffic, a 40 ft. width was adopted in the permit
requested. However, if the District Engineer feels that the width should
be increased to 50 ft. the Board of C unty Commissioners will ake this
change but we wish to point out that navigation data indicate: that there
S: is no necessity for a width greater than 40 f.t.
It is proposed to control the main look by two hydraulically
controlled bottom hinged gates 18 -ft. high by 40 ft. long. The bottom
hinges on these gates are sealed for protection and the gates in the fully
; : opened position are lowered into a recess. It is proposed to operate the
Sates by synchronized hydraulically operated arms. Provision will also be
S "made for inserting needle beams for unwatering each one of the gates when
S'The secondary or small boat look will be 18 ft. wide by 60 ft. long
and will have its si1l at approximately 7.5 ft. below mean low water.
SIt will be controlled by two hydraulically controlled bottom hinged
gates each 18 ft, long by 11 ft. high designed and operated similarly
to the gates of the large lock.
Flood flows will be taken care of through the dam structure by
six openings 10 ft. wide and extending down to an elevation of -7.5. ':
Provision will be made by the use of tide gates to prevent backflow of
salt water at periods of low flow.
The gates will be so designed as to permit their operation in
the large look in two minutes for each gate and in the small lock in one
and one-half minutes for each gate. 'It is proposed to fill and empty
the look chambers with fresh water taken from upstream by means of pumps.
For the main lock it is proposed to install two 50,000 gal. p.m. pumps
which will raise or lower the large lock level at the rate of one foot per
minute. As the average head will be less than 2 ft. the average time for
adjusting the water level in said lock chamber will be less than 2 minutes.
It will therefore be seen that there will be very little obstruction to.
traffic or loss of time in lock operations. In the case of a favorable
lockage in the large lock chamber 2 minutes will be required to close the
gate, about 2 minutes to adjust the water in the lock chamber, and 2 minutes
to lower the gate, making a total of about 6 minutes. The lock operator,
in many cases, can observe an approaching boat in time so that he can prepare
the lock chamber for a favorable lockage. However, in cases where an un-
favorable lockage must be made, about an additional 6 minutes will be
required or a total of 12 minutes. Of courseyou will have to add to
these figures the time required by boats to enter and leave the lock.
Mr. Stephens has made a careful study of the total lost time to present
It traffic with the proposed lo16ck. He will present this to you in detail
in his testimony. It is expected that the locks will have to be used
o. n the average of 7 or 8 months during the year. During the other 4 or
, 5 months the drainage flows will be high enough to maintain the desired
fresh water levels and to exclude all salt water in the canal at the
S loci site with the gates open. The gates will be so designed as to'permit
.them to be removed for repair and maintenance without unwatering the gate
chamber although provision is made for unwatering in case of emergency.
.- We estimate that the gates can be removed or installed in not to exceed
a 4 hour period which would necessitate the closing of one set of locks
during the quiet time of night. This would probably be between'the hours
of '11 P.M. and 3 A.M. As traffic is very light at night, with ample notice,
there should be very little inconvenience occasioned by this procedure and
Sit would probably not be necessary to remove the gates any oftener than once
each year and then for cleaning, painting and maintenance, except of course
Sin case of emergency. It is proposed to have a standby power unit so that
in case of a failure of city power operation of the lock would continue.
It is also planned to have an operating crew on duty 24 hours each day and
to install operating units in duplicate so as to minimize the chances of an
Results of studies of model tests for similar lock structures and
a study of the literature regarding the phenomena of density current have
.been utilized in the design of the look in question and its operation so as
Sto keep all possibility of salt entering the upper pool at an absolute
minimum. However, even in the event that small amounts of saline water pass
Into the upper pool it has been found by observation that such waters will
S, concentrate in small recessed areas at the bottom just above the lock and
Sdam and that by properly controlled bleeding operations said salt water may
) I :I _~
be drawn off from time to time and deposited down the stream as required.
Our look design provides for bleeder lines near the bottom of the structure
so that such saline water can be drawn off in this manner.
TWe are satisfied from a careful survey of the problem that the
proposed looks at the N.W. 20th St. location as planned will offer a minimum
of inconvenience to water-borne traffic and will meet a very great need in
checking salt water intrusion and for maintaining fresh water levels which
will far outweigh in benefits the delays to navigation and the costs of the
project. In general the objectives in the operation of the proposed structure
at N.W. 20th St. are the same as for the existing temporary structure and the
old pneumatic dam at IT.W. 36th St. However, it is anticipated that better
results will be obtained with the new structure both in maintaining the fresh
water table level in periods of low flow and expediting the drainage in periods
of high flow.' Among the benefits which will result from the proposed project
Share the following: "
1i. There will be a very material reduction in-tidal flows while the lock
is in operation. This reduction will not only exist above the lock but also .
below it. Th1is will be a great aid to navigation.
2. Above the locks the water level will be fixed at about the present high
tide' level while the lock is in operation which will be of value to navigation
particularly in the upper reaches where the depths are shallow. This fixed level
will also be advantageous for the mooring, handling and docking of vessels.
3. Above the locks there will be freshvater mooring 12 months in the year
instead of the present 4 or 5 months in the year.
4. There will be no limit on future expansion of navigation on the Miami
and Tamiami Canals as the freshwater basins can be extended as required by
5#. The structure will make freshwater available in the area above the
locks for industry.
: .. ,,: -10-
6. The city of Miami's tremendous investment in the well
fields will be protected.
7. It will protect the peat soils against burning and
8 8. It will stop the salting of agricultural soils and will-
:,:.. reverse this tendency permitting fresh water to leach the salt
out of much of the land already salted.
9.:: It wili make Palmer Lake a fresh water lake thereby changing
it from a menace from the salt intrusion angle, to a highly desirable
freshwater lake for the mooring of vessels.
S 10. The project will: not interfere with drainage when drainage
Sis needed.. '
IN COITCLUSION, I would like to point out that the County
,:Commission of Dade County has a mandate to provide water control.
The most important single source of salt water intrusion is the Miami Canal.
It therefore becomes essential in carrying out this plan that provision be made
to stop salt water intrusion and to maintain fresh after levels in the land
as nearly as possible at an elevation of 2. above mean sea level.
SLocks have been built and are operating satisfactorily on other
Federal navigable waterway projects in Florida. On the Okeeohobee Cross
Florida waterway there are three locks, one being at Stuart, one at Moore-
haven, and one at Ortona. My information is that these locks do not con-
stitute a serious delay to navigation, although the lift involved at these
S locks is many times the lift required for our proposed structure.
After very careful consideration we have reached the conclusion i
.that the only possible and effective location for the proposed look and
dam is at N.W. 20th St. We have therefore made a thorough study of
the traffic situation there and have prepared a double lock design for
location which we believe will serve adequately to permit passage of
navigation with the least possible interference and at the same time will
provide for the.control of fresh water levels and will stop intrusion of
appreciable quantities of salt water from passing above that point. In t
view of the fact that this is the only location which we have found that
will do the job adequately we are requesting a permit to install this
structure in the navigable waters at N.W. 20th St. and ask that you grant
said permit .
I -- T-l - .ff ih-m f -bc
mHnv 6K' SPTBrpH N
SSTATEMENT BY JOBItN G. STEPHE.S
Dade County TWater Control Engineer
U. S. Engineer Hearing
July 11, 1946
My name is John C. Stephens. I am employed by Dade County
'as Water Cpntrol Engineer in connection with the execution of the
Water Control Program undertaken by this County. In this position
I have been directly charged with making the studies and plans
under the direction of Mr. Earle M. Rader and with the advice of
During the past twelve (12) years, I have been employed as
an Agricultural and Drainage Engineer for the United States Department
of Agriculture. Six (6) of these years have been spent as Engineer
in the Everglades area making surveys and water control plans for
the southeastern part of the .State under the direction of the
Soil Conservation Service Bureau.
The dry period of 1938-39 made it apparent to :both agricultural
interests and municipalities along the southeastern coast, that
conservation and control of water in this area is highly important
for the preservation of organic soils, for irrigation of farm crops,
for protecting coastal soil from salt intrusion, and for replenishment
of sub-surface storage, and protection of such storage from salt
intrusion, from which municipal supplies.are pumped.
In 1939 the U. S. Geological: Survey began an intensive
investigation of the water resources of south Florida; and the Soil
Conservation Service undertook surveys for determining land use
capabilities in the district and the water control measures
necessary for developing these capabilities. As a result of this
work, plus studies,carried on by the Agricultural Experiment Stations
of the University of Florida, the Bureau of Agricultural Engineering,
Sthe Bureau of Plant Industry, the National Park Service, the Florida
Fire Control Commission, the U. S. Engineers, the E-m rglades Drainage
District, the various sub-drainage districts, the U. S. ITeather
Bureau, the U. S. Coast and Geodetic Survey, various Municipalities,
and other Agencies4 there had been outlined by 1945, sufficient
S data concerning the: natural features of the area to sketch out j
: master plan of water control for the entire Everglades Area. The
S object of such a plan being neither drainage nor irrigation but
Water control in the fullest sense of the word. In 1945 this plan
w as outlined by W. Turner Wallis, their Engineer for the Everglades
S Drainage District, who drew information from these data and presented
his report to -the Everglades Drainage District, as a preliminary
report to one which is now in print by the Agricultural Experiment
Stations of the University of Florida and the Soil Conservation
Service of U. S. Department of Agriculture and will be issued in
the near future.
The essence such a plan follows a definite pattern in
accord with the capability of the different lands within the area
and is based on sound engineering and economic principles. Water
Control in this area involves drainage and those portions, where
and when, an excess of water interferes with the best use of the
lands, and irrigation of those portions where and vwen a lack of
water interferes with best use of them. In cropped land, the ground
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water table should be maintained at the highest elevation that
will permit good cr6p growth, in order that subsidence of the ground
surface by oxidation and by fires may be held to the minimum. In
non-agricultural areas the water table should be held .at or above
the ground surface to prevent subsidence by oxidation or burning.
In areas devoted to wild life, the requirements for that purpose
should be observed. In allareas, as large a portion of the water
should be conserved as possible consistent with the designated major
use of the land and health considerations, to supply water needed
for irrigation in dry periods and to furnish domestic and municipal
supplies for people and cities in and bordering the Everglades.
As one of those primarily involved in directing the engineering
surveys and later in compiling the data, I was keenly disappointed
vhen it became parent that, even though the physical surveys and
other data were for the first time complete enough to insure the' ::
technical success of the project, no political entity or finances
existed to carry out the project as formulated. Many of us who ,
had devoted bver five (5) years of work conducting these studies
were hopeful that this situation wculd be remedied by the State
Legislature wherein recommended water control practices could be .
included in an overall State program. However, the past Legislature
did not see fit to authorize such work on this basis, but due to
the extreme need'for the work in this County, the Legislature did
authorize the Dade County Water Conservation District, the details
of which have been previously presented by M.r. Campbell. In late
1945, I requested, and was granted leave, by the U. S. Department
of Agriculture in order to a ssist the Dade County Engineer in
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preparing plans for water control. It is Dade County's program to
so formulate such plans which will later fit into the broader, over-
all pattern of water control for the entire Everglades area which is
essential, and must come sooner or later. In the meantime, because
of the urgent nature of the situation which menaces our vital
natural resources of soil and water, Dade County's part of this
program must be carried out without further delay.
Early in my studies of this problem, it became apparent that
control structures must be established on the Miami Canal if
encroachment of salt water was to be checked; if the fresh water
level was to be maintained high enough to control fires and oxi-
dation in the ora_-ni~ soils and if sufficient water was to be
conserved to supply the amount of non-saline water needed for
irrigation and for domestic and municipal purposes. ie considered
a number of different possible site locations but found that serious
consideration could only be given to a site on the Miami River above
the N. W. 27th Avenue Bridge (called herein the N. W. 20th Street
site) and the site at N. W. 36th Street where the present temporary
control is installed. Along with the 36th Street site it would be
necessary also to place a lock in the Tamiami Canal near the junction
with the Miami Canal. The last tro locks have been advocated by
some of the navigation interests located on the Miami Canal above
the proposed N. W. 20th Street location.
Before going any further, I should like to state it is my
positive opinion that the proposed control dam at N. I1. 20th Street
is necessary if further encroachment of salt water is to be stopped
and if the Iiami well fields are to be protected. It is further my
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opinion that the expenditures involved will bring benefits many
times greater than these expenditures. We have given very careful
consideration and study to the possibility of substituting two sites -
one at 36th Street on the Miami Canal, and the other on the Tamiami
Canal above its junction -- for the proposed location at N. W. 20th
Street below the junction of the two canals. This examination
included the study of the lock sites to determine their geological
conditions and other conditions affecting the cost of construction
of the proposed locks, the salt water encroachment problem, tidal
and stream flows and other features affecting look location and
design. We have also studied the navigation to determine lock re-
quirements and have made geological and ground water studies,
industrial surveys, and investigations of navigation costs and problems.
The result of the above examinations showed the following
advantages for the N. W. 20th Street site: First, greater protection
to the present domestic water supply serving the majority of Greater
Miami. Second, increased conservation of fresh water. The value
of an industrial tract of approximately 3 square miles, now under-
lain by saline ground water, would be greatly increased by providing
this area with an adequate supply of freshwater. Third,advantages
in providing fresh water in the canal and Palmer Lake, as contrasted
to salt water, for longer preservation of structures, hulls and
other items with consequent lower maintenance costs. Fourth,
greater economy in construction, operation, and maintenance costs
of the proposed look, Fifth, advantages to future water traffic
and industrial development by allowing for future canalization to
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