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Part-ke vwho Tosti- fied at LIST OF PARTIES TO TESTIFY AT MIAMI CANAL LOCK HEARIIIG TO BE HELD JULY 11, 1946 SHUGE PETERS EARLE 1M. READER PARK 'CA.PBELL STHEODORE KNAPPEN "' JOHN C. STEFHENS 1GERALD G(. PARKER 7, DEA B. BOGART 8. i.: A. GLASS 0 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 Control Program. 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 DEWEY HILSABECK 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. -1- 10. 11, 12. 13. 14, 0 . 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 JAMES OBER Vice-President of Florida Wild Life Federation. 17. 18. J; 9 S -s2 Beard oi .41iCT S * RESOLUTION . ... 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. -2- I~ 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 % 1 r --- ---- -- ----.--.- ..r I I - tLogart S 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 Page 2. .. - ~ ~ '':; 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 Scandals. 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. Page 3. . ...'-. .. .i'' I3.. .. I.I I . ., '. . ,.... .. te i the canals. 16 4. ... t o on.' .-' ,. ., ,- ;, f + ,. ,, : : '* \ -. ,. . ",., 4 ." j -- 1 f. Si ,, as f ,. .. v e ..-4 .4 4 .4.. 4'i ; .. ' "' -* ;' "*.. -' ", -, : , can be halted i the canals. Th, v*'oua teiionry .sait"tarrieri CoI- '- S .. .. 4 D. ,' "744 4-;.. .' ...- '. P "at. B. B .' ..-" '" .' .' , J 47 ., .. .. .,;- ."', ... -: 4, ,* ,*: **" ., ,e 4 v .- .. . wa te .i t is. d e sira .b. 'le .tuo t; ... ,. 4. fe a i b l 4 -' .. ,. *. . .- V47 ': .'4' ^ .",,, ":e '--. *s.* e .r :le "a s *-o",1. o e. .s ". ;^* .' ,. ^ . S' '- i .. r-"4 *:. -. ,' ... .- : *' "'l.'5 ; ; A' .-4'., . .i. o. ,. .. 4 . "4 "4" .+ .. ~_4' '- '.I '4 '. .,' 4 '4 " .. -., .. ^ :* .; .-.^ l ,. ; ,.+.. ... .+ ....- ,- .. ..;'4 4. ... .4. ,.. . .,4- ,. .. . July9,. 4 $ .. -' e B. -g. p4. ,, .,.. .* " .. 4' 4. 4 *' "-, ' ..; -4 4-. 41 : 4. 4 4 I 4 ..- ., ., ... "' '." '. 4 .,4 ." ,,44" i 4, :. ., 4 .4 ". 4 4 4 4 ...' .. P'.-- 1 , '3 '. "4., 4 -'" P.ag, ,. ,''" 4 .. .... Q"_ " ..r.44 444 '. -.4 ' 4.- ,. .44 74 .4. .4 ... ,, - S 13?-)I I I- I I . COPY 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- pleted.. . 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 polluted. . Respectfully submitted, (.Si ned) T. E.: Cato T. E. Cato, M.D. TEC:ah Health Commissioner L er-I i 14 AGRICULTURAL EXPERIMENT STATIONS Everglades Experiment Station Belle Glade, Florida Colonel A. B. Jones, District Engineer U. S. Engineer Office Jacksonville, Florida, Re: Soil and Water Conservation in Relation to Miami River Improve- ment. ; 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, 4* 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 hearing. 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 possible. iiii( : 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 important: (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 1_ ( 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, ' L._ M, 1 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 District Engineer U. S. Engineer's Office: Jacksonville, Florida 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 -2- 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 plants. 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 ;existence here. ** Very sincerely yours (Signed) David Fairchild. D 'avid Fairchild -t 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 chloride. 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 conditions. 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. ~L(I S 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 and beets. 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 this area. -2" _ .. 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 more. frequently. 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 -3- 1 0 M SDEPARTMEIT OF WATER AND SEWERS CITY OF MIAMI P. 0. Box 4832 S"Miami. 31, Florida :July 10,. 1946 Wa. r Department Engineering Office Jacksonville, Florida : Gentlemen: . 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.: Yours truly, (Signed) A, Glass W. A. Glass Diroctor WAG/g Enclosures COPY 0 _ij( I I 1 1 I_ 1_ ( _;-_, ~) COPY A BRIEF IT SUPPORT OF TE DADE COUNTY ENGINEER DEPARTMENT PLAN FOR WATER CONTROL ON THE MIAMI CANAL By 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 Miami, Florida 1 I * 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 drainage. ' 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 -4- :_I I 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. -5- 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. -7- i.I, , 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. 7 0 I i ii 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 months' ' During this time, the concentrations of salt in the Miami Canal are very large, approaching sea water. The effect !i ii S.: : ^ '. 2 / .' ' ^*11:1 - -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 2. 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 concentrations. 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 I *'/ ', ' 4. . , "*.. . V"* r 0. d '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 -. .--' .'. ,. . S* ;.. '*^ '' 4; .'' . a . i * St I . S k, ' r 444 .- > . I * 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: A :r ;7 1 'II I I n. L _ !7 .4 I : ) " C 0 I-4 H H 7* 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 mooring basin. 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 :I 10. 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 water supply.' 2. Tfe structure cannot be located further upstream and be fully effective. 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 . 11. 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 ... :- Induc- t;%'.C MAULE INDUSTRIES Ojus, Florida 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 Jacl:sonville, Fla. . ,- :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 be. 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. Yours respectfully MALE IFDIIOSTPIES '(SGned)R. C. G 'illiams R G. Williams Partner SF 7r P Lt MR'^ i;.:ii.' 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 SWar Department United States Engineers Office Jacksonville, Florida: .Attention: A. B. Jones,.Oolonel District Engineer Dear Sir:. 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 .of.Greater Miami. 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 ,1) . ~3rle 1 .. -C~. BELCHER OIL COMPANY M::iami Florida ' July 9, 1946 1., '' ^ : ,' l 1,4 .: Col. A. B. Jones " District Engineer United States Engineers SJacksonville, Florida Dear Sir: 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- plated construction. 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' President CB C:M ... -..... .; . S aralY FPnri!: q k*AY' COPY UNITED STATES ,DEPARTiENUT OF TBE INTERIOR GEOLOGICAL SURVEY P.O. Box 2529 Miami 15, Fla. :July 5, 1946 The bDisbtrict Enineer, . United States Engineer Department, ' Jacksonville, Fla. 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 . COPY SUMLiARY OF CONCLUSIONS REACHED AFTER SIX YEARS OF INVESTIGATIONS OF THE GEOLOGY AND GROUND WATER OF THE GREATER MIAMI AREA, FLORIDA by 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. -2- .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 accomplish this. (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- tion. (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. -3- ~~ .I (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 v "~r7h ~$h ~e~~ss~ 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_ __ -2- 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 program. 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. Ilts3.c011 / LI Nn'.5 ^r~~~I r-r' True IMALCOLM PIRNIE ENGINEERS New York 18, N. Y. S;: .STATEMENT OF MALCOLM PIRlIIE, CONSULTING ENGINEER :.FOR .'DEPARTMETrT OF WATER AID SEWERS, CITY OF MIAMI SUBMITTED TO U D WAR DEPARTMENT i: cUN.. UITED STATES ENGINEER OFFICE JACKSONVILLE, FLA. AT PUBLIC HEARING ON APPLICATION OF DADE COUNTY 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 War Department United States Engineer Office Jacksonville, Florida Gentlemen: 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 Malcolm Pirnie TAP: nb Brief Statement Descriptive of Ground Water Reservoir in Dade County and Immediate Need for Protective Water Level Controls with particular reference to Miami-and Tamiami Canals General 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. -1- 1~ 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. -2- __ U1 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- I 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- ing canals. 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. -4- 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- tions. 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 -5- I I I I I I I -- ~~ ~ m 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 Florida. 1111 11 I II I I ., I _ r t1a rj 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 Program. 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 from later. I -2- .. 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. I -3- 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. -4- 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 -5- 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 ; R -6- 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 necessary. 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. - .. -7- 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 -8- 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 operating failure. 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 _~ -9- 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 industry. . 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 oxidization. 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 -11- 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 /^ r. *'. -,'l .-I' .*if I- SSTATEMENT BY JOBItN G. STEPHE.S Dade County TWater Control Engineer at 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 various consultants. 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 -1- __ 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 -2- , ,, :, ,r ..... .. 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 -3- i *i -:) .-: i : 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 I I __M II ' 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 -5- .. :. : .1 -.'...--. -il .i - " |