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FLRD GEOLOSk ( IC SUfRiW COPYRIGHT NOTICE [year of publication as printed] Florida Geological Survey [source text] The Florida Geological Survey holds all rights to the source text of this electronic resource on behalf of the State of Florida. The Florida Geological Survey shall be considered the copyright holder for the text of this publication. Under the Statutes of the State of Florida (FS 257.05; 257.105, and 377.075), the Florida Geologic Survey (Tallahassee, FL), publisher of the Florida Geologic Survey, as a division of state government, makes its documents public (i.e., published) and extends to the state's official agencies and libraries, including the University of Florida's Smathers Libraries, rights of reproduction. The Florida Geological Survey has made its publications available to the University of Florida, on behalf of the State University System of Florida, for the purpose of digitization and Internet distribution. The Florida Geological Survey reserves all rights to its publications. All uses, excluding those made under "fair use" provisions of U.S. copyright legislation (U.S. Code, Title 17, Section 107), are restricted. Contact the Florida Geological Survey for additional information and permissions. 2 iv 1.9- ~:- -----Ar 'S' -~~~~ 4 i''P ~ 5t' ~~ STATE OF FLORIDA DEPARTMENT OF NATURAL RESOURCES Harmon Shields, Executive Director DIVISION OF INTERIOR RESOURCES Charles M. Sanders, Director BUREAU OF GEOLOGY Charles W. Hendry, Jr., Chief REPORT OF INVESTIGATIONS NO. 71 CHEMICAL AND BIOLOGICAL CONDITIONS OF LAKE OKEECHOBEE, FLORIDA, 1969- 72 By Boyd F. Joyner Prepared by the UNITED STATES GEOLOGICAL SURVEY in cooperation with the BUREAU OF GEOLOGY DIVISION OF INTERIOR RESOURCES FLORIDA DEPARTMENT OF NATURAL RESOURCES and the CENTRAL AND SOUTHERN FLORIDA FLOOD CONTROL DISTRICT TALLAHASSEE, FLORIDA 1974 DEPARTMENT OF NATURAL RESOURCES REUBIN O'D. ASKEW Governor DOROTHY W. GLISSON Secretary of State THOMAS D. OMALLEY Treasurer RALPH D. TURLINGTON Commissioner of Education ROBERT L.. SHEVIN Attorney General FRED O. DICKINSON, JR. Comptroller DOYLE CONNER Commissioner ofAgriculture HARMON W. SHIELDS Executive Director LETTER OF TRANSMITTAL Bureau of Geology Tallahassee October 16, 1974 Honorable Reubin O'D. Askew, Chairman Department of Natural Resources Tallahassee, Florida Dear Governor Askew: We are pleased to make available the report, "Chemical and Biological Conditions of Lake Okeechobee, Florida, 1969 72" by Boyd F. Joyner. The purpose of this report is to document the present status of Lake Okeechobee with respect to nutrient enrichment. An assessment of the source and status of enrichment of the lake system is necessary for all future studies or action, and for establishing a decision base line for managing water and water quality. Respectfully yours, Charles W. Hendry, Jr., Chief Bureau of Geology Completed manuscript received May 8, 1974 Printed for the Florida Department of Natural Resources Division of Interior Resources Bureau of Geology Tallahassee 1974 iv CONTENTS Summary ................. ........... ........................... 1 Introduction ....................... .................... 3 Purpose, scope, and sampling procedure ................................ 3 Acknowledgments ....................... .............. .......... 8 Description of Lake Okeechobee and drainage system ...... ................... 9 History of the lake ................................................ 9 Physical features ..................... ........ ................... 9 Tributaries...................................................................... 10 Drainage .................. ........ .... ........................ 11 Hydrologic characteristics, 1969 70 ........................... ........ 12 Precipitation .................................................. 12 Inflow ........................... ........ ................. 13 Outflow .................................................... 14 Water budget, January 1969 July 1970 ............................... 15 Chemical and physical characteristics of water and sediment, 1969 70 ........... 17 Lake Okeechobee ....................................... ......... 17 Physical characteristics of water ................................... 17 Major chemical constituents .................................... 19 Distribution of nitrogen and phosphorus ............................. 22 Trace elements ................................................ 28 Pesticides ..................................................... 28 Bottom sediments ............................................ 30 Tributaries .......... ........................................... 30 Drainage canals ................................................... 39 Nitrogen and phosphorus in rainfall .................................... 40 Water-quality budget, 1969 70 .......................................... 43 Biological characteristics of Lake Okeechobee, 1969 72 ...................... 45 Phytoplankton ........ .......................................... 45 Benthic organisms .................................................. 50 Chemical, physical, and biological characteristics of water and sediment, 1970 72 ....................................... ........ 52 Chemical and physical characteristics of water ........................... 52 Physical characteristics and dissolved solids ........................... 52 Nitrogen and phosphorus ................................... .... 53 Trace elements .................................................. 54 Chemical characteristics of bottom sediments ............................ 54 Biological characteristics ............................................ 54 Phytoplankton ............................................... 54 Benthic organisms .............................................. 55 Eutrophic assessment .......................................... ..... 55 Selected references ................................... ............... 59 Appendix ................... ........ .......... .. .............. 63 ILLUSTRATIONS Figure Page 1. Map of Lake Okeechobee and drainage system showing location of sampling points ............................ ... ............. 4 IA. Rainfall over Lake Okeechobee, January 1969 July 1970 ............. 13 2. Average seasonal variations of dissolved solids, dissolved oxygen, and water temperature in Lake Okeechobee ................ .............. 21 3. Average distribution of nitrogen (N) in Lake Okeechobee .............. 23 4. Areal and seasonal variations of nitrogen (N) in Lake Okeechobee ........ 24 5. Average distribution of phosphorus (P) in Lake Okeeheechobee ............ 26 6. Areal and seasonal variations of phosphorus (P) in Lake Okeechobee ..... 27 7. Nitrogen (N) in tributaries .................................... 35 8. Phosphorus (P) in tributaries .................... .................. 36 TABLES Table Page 1. Locations of routing sampling sites on Lake Okeechobee .............. 5 2. Chemical and biological sampling of Lake Okeechobee .................. 7 3. Water budget for Lake Okeechobee, January 1, 1969, to July 31, 1970 ... 16 4. Trace metal concentrations in Lake Okeechobee .................... 29 5. Pesticide analyses of water and bottom sediment for Lake Okeechobee .. 31 6. Average chemical analyses of bottom sediments in Lake Okeechobee ..... 37 7. Nitrogen and phosphorus in rainfall at Hurricane Gate Structure 1 ...... 41 8. Generalized water and dissolved solids budget for Lake Okeechobee (January 1, 1969 to January 31, 1970) ................... ........ 44 vi TABLES Continued Table Page 9. Generalized nitrogen (N) budget for Lake Okeechobee, January 1, 1969 to January 31, 1970 ......... ... ..... ... ....... ... ........... 46 10. Generalized phosphorus (P) budget for Lake Okeechobee, January 1, 1969 to January 31, 1970 ......... ................................ 47 11. Phytoplankton observed in Lake Okeechobee .... ................ 49 12. Average number of bottom organisms per square meter, January, May, August, 1969, and January 1970 .............................. ... 51 13. Chemical analyses of water in Lake Okeechobee .................... 65 14. Chemical analyses of water in tributaries to Lake Okeechobee .......... 75 15. Chemical analyses of water in drainage canals of Lake Okeechobee ....... 81 16. Phytoplankton in Lake Okeechobee .......................... 85 17. Chemical and biological analyses of water and bottom sediments in Lake Okeechobee, Kissimmee River and Taylor Creek, October 1970 May 1972 86 18. Phytoplankton observed in Lake Okeechobee, Kissimmee River and Taylor Creek, August 1971 -May 1972 ................................. 93 19. Average number of bottom organisms per square meter in Lake Okeechobee November 1971 and May 1972 ......................... 94 CHEMICAL AND BIOLOGICAL CONDITIONS OF LAKE OKEECHOBEE, FLORIDA, 1969-72 By Boyd F. Joyner SUMMARY Nutrients are adequate in water in Lake Okeechobee for algal growth. Organic nitrogen averaged 1.3 mg/1 (milligrams per liter) and accounted for approximately 86 percent of the total nitrogen, and total phosphorus (P) averaged 0.05 mg/l. The average dissolved-solids content of the lake water was 288 mg/1 in 1969 72 compared to 190 mg/1 in 1940 41. Dilution and flushing from greater-than-average rainfall and use by algae, however, decreased dissolved solids from 309 mg/1 in January 1969 to 210 mg/l in April 1970, near average value for the 1940 41 sampling. Rainfall contributes significant amounts of nutrients to the lake, and concentrations in rain are at times similar to concentrations in both the lake and its major tributaries. Rainfall contributes 30 percent of the total nitrogen and 21 percent of the total phosphorus load. Major tributary sources include the Kissimmee River, which contributes 39 percent of the total nitrogen and 36 percent of the phosphorus loads, and Taylor Creek, which contributes 26 percent of the total phosphorus load. Twenty-two percent of the nitrogen and 36 percent of the phosphorus entering Lake Okeechobee is retained within the bottom sediments and biota. Water pumped from agricultural areas to the southeast is generally the poorest in quality of all water entering Lake Okeechobee. Trace elements in the lake water are in low concentrations, but are usually adequate for sustaining healthy algal growth. Boron, aluminum, copper, and manganese, are below the probable minimum requirements as given in literature. Low concentrations of nitrite and ammonia indicate an absence of significant organic pollution. Bottom sediments contain appreciable quantities of iron, nitrogen, and phosphorus, with the nitrogen and phosphorus being primarily organic, consistent with the lake behaving as a nutrient sink and reservoir. The number and variety of benthic organisms were well below levels normally considered indicative of highly eutrophic waters. Numbers of nuisance species were generally low. The warm water (up to 340C) and adequate nutrient concentrations are conducive to high biologic productivity; however, algal growth may be inhibited by the relatively high turbidity of the lake. Secchi-disc readings were generally less than 1 foot. Turbidity is generally highest during low lake stages. Color of the water is generally less than 50 units but it can run as high as 240 units BUREAU OF GEOLOGY because of inflow of highly colored water from tributaries and back pumped water from drainage canals. Dynamic shifts in phytoplankton population, reflecting a change in environmental conditions within the lake, occurred between January and July 1970. Phytoplankton concentration was generally less than 50 cells/ml (cells per milliliter) before January 1970, and the characteristic organism present was Pediastrum simplex, a green alga typical of early eutrophic lakes. Average phytoplankton concentration was 32,300 cells/ml in July 1970, 25,400 cells/ml in October 1970, and 149,630 cells/ml in January 1971, and decreased to 7,956 cells/ml in April 1971. The average phytoplankton concentration was 11,100 cells/mi in August 1971, 38,400 cells/ml in November 1971, 8,400 cells/ml in February 1972, and 24,700 cells/ml in May 1972. The dominant organism after July 1970 was Aphanizomenon holsaticum, a blue-green alga typical of eutrophic lakes. In the northern part of the lake, concentration of phytoplankton increased to bloom levels and dominant species changed from green to blue-green algae after a period of heavy abnormal inflow from tributaries and rainfall (late 1969 to March 1970), with consequent increased influx of nutrients to the lake. Increases in concentrations of nutrients such as silica, nitrate, phosphate, iron, and organic material were relatively large in the northern part of Lake Okeechobee in January 1970 after heavy runoff. Data indicate decreased concentrations of these nutrients during the subsequent phytoplankton bloom in July 1970. Increased concentration of phytoplankton to bloom levels (75,000 cells/ml), consisting of the blue-green algae, Anabaena circinalis, associated with eutrophic lakes, occurred also in Blue Cypress Lake on the St. Johns River approximately 35 miles north of Lake Okeechobee, in July 1970. There was no evidence, however, that this bloom persisted into 1971 72 in Blue Cypress Lake. Blue Cypress Lake is affected by man less than Lake Okeechobee. The data obtained and evaluated during the investigation suggest that Lake Okeechobee is in an early eutrophic condition; however, regional comparisons suggest that the water quality of Lake Okeechobee, as of 1969 72, is not significantly different from that of other water bodies in southern peninsular Florida. Extensive physical, chemical, and biologic variability within the lake system over a short time span have been documented. As no reliable comprehensive nutrient or biologic data are available for historical comparisons, and, as the investigation coincided with a period of abnormal rainfall and runoff resulting in a relatively high nutrient flux to the lake, prediction of long-term trends is not currently possible. REPORT OF INVESTIGATIONS NO. 71 INTRODUCTION Lake Okeechobee in south central Florida is a major water-storage, flood-retention, recreation, fish, and wildlife area. Its water directly supplies several towns and is used to irrigate extensive agricultural areas to the so-uth. Ft. Myers, by diversion from the Caloosahatchee River, utilizes the water for its public supply, and Lee County plans to divert water for public supply from the Caloosahatchee River, which receives much of its flow from Lake Okeechobee by way of the Caloosahatchee Canal. At times, for drainage and flood-control needs, flow through the network of canals is reversed; and mineralized, nutrient-rich drainage water from the leached agricultural muckland south of the lake is returned to the lake. Also, increased use of fertilizers and pesticides on farmland and increased land use in the drainage area north of Lake Okeechobee have caused an increase in dissolved solids and nutrients carried to the lake by some tributary streams. PURPOSE, SCOPE, AND SAMPLING PROCEDURE Recognizing that the enrichment or eutrophication of lake waters, although a natural process, may be accelerated by man's activities, the present status of the lake, with respect to nutrient enrichment, is the primary concern of this report. An assessment of the source and status of enrichment of the lake system is necessary for all future studies or actions and for establishing a decision base line for managing water and water quality. Parker and others (1955) generated background chemical data (1940 41) used in the present study area, as did Holcomb (1968), and Duchrow (1970), for the period immediately preceding the start of the present investigation. The U. S. Geological Survey, in cooperation with the Central and Southern Florida Flood Control District, made such an assessment of Lake Okeechobee over a 41-month period, January 1969 through May 1972. The objectives were: (1) to determine the source and quantities of dissolved mineral matter and nutrients entering and leaving the lake, (2) to determine the occurrence and distribution of nitrogen, phosphorus, trace elements, selected key biological factors, and selected physical and chemical parameters pertaining to the lake, and (3) to define the condition of the lake with respect to its present state of eutrophication. To obtain the data necessary for the assessment, at least some of 18 sites in the lake (fig. 1, table 1)were sampled 13 times. Each sampling run or traverse is called, in this report, a transect. In general, these transects were tied in to BUREAU OF GEOLOGY Fgure I. Map of Lake Okeechobee and drainage system showing location of sampling sites. REPORT OF INVESTIGATIONS NO. 71 Table 1 Locations of routine sampling sites on Lake Okeechobee Comment Okeechobee Waterway Light-FIR 4 sec "2" Okeechobee Waterway Light-Fl 4 sec "7" Daybeacon R "2" Site 1 2 3 4 5 6 7 8 9 10 11 Coordinates 26047'45" N 80051'10" W 26049'30" N 80047'05" W 26052'05" N 80o1'05" W 26055'00" N 80055'00" W 26057'45" N 80058'40" W 26059'45" N 80055'00" W 27002'30" N 80051'05" W 27005'05" N 80047'10" W 27009'30" N 80047'10"W 27003'05"' N 80043'55" W 27001'00" N 80040'15" W 26059'05" N 80037'10" W 26055'00" N 80040'55" W 26052'45" N 80,44'05" W do. Martin do. Okeechobee Waterway Light Fl 4 sec "1" Okeechobee Waterway Okeechobee Waterway County Palm Beach do. do. Glades do. Okeechobee Light-F14 Sec do. Palm Beach do. BUREAU OF GEOLOGY 2655'30" N 8047'55" W 26049'30" N 80040'05" W 27004'46" N 80053'23" W do. do. Glades 18 26048'52" N do. 80O56'50" W seasonal criteria, that is, they corresponded to cold-, dry-, and hot (wet)-weather periods. The dates on which the transects were made are listed in the following table: Type of data collected 1-16 1-16 1-18 1-16, 18 2, 5, 8, 9, 12, 15 Do Do Do Do Do Do See table 2 Do Do Do In general, data collected same as in table 2 except for pesticides, chlorophyll, and seston. BOD and TOC analyses included (see table 13 and 17) Do Do Do Do Do Do, trace elements (table 17) determined on sample collected from site 15 Do Do, trace elements determined on sample collected from site 15 In addition to these 13 transects, daily measurements of specific conductance and turbidity and monthly analyses for nitrogen species, phosphorus, and major inorganic ions were obtained at site 16. Vertical profiles, which included field measurements and analysis for nitrogen species, phosphorus, and major inorganic ions, were made at sites 1,6, and 11 during the first four transects. Transect Number Date Sites Sampled Jan. 1969 May Aug. Jan. 1970 Apr. July Oct. Jan. 1971 April Aug. Nov. Feb. 1972 May Table 2 Chemical and biological sampling of Lake Okeechobee Type of Data Sampling 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 CHEMISTRY OF WATER Surface: Field Measurementsj/ Laboratory analysis: Complete analysis (unfiltered)2/ S Complete analysis (filtered) 2. S : ,Trace elements / Field measurements./ Laboratory analysis: Complete analysis (unfiltered) ~y CHEMISTRY OF BOTTOM SEDIMENTS PESTICIDES (water and sediments) BIOLOGY Surface: Plankton Chlorophyll Seston (suspended material) Net tow Bottom Fauna x x x x x x x x x x x x x x x x x x x x x x x x x x x x x x x x x x x x x x x x x x x x x x x x x x x x x x x x x x x x x x x x X X X X x x x x X X x x x x x x x x x x x x x x x x SECCHI DISC x x x I/ Specific conductance, dissolved oxygen, temperature, pH and alkalinity. Major inorganic ions + turbidity, ortho and total phosphate and complete nitrogen cycle. Spectrographic analysis (field filtered and acidified). Iron, manganese, nitrogen, phosphorus (analyses made by Florida Department of Air and Pollution Control). BUREAU OF GEOLOGY Inflow tributaries, and also the inflow and outflow canals (if they were flowing), were generally sampled monthly through 1970. The Kissimmee River and Taylor Creek were sampled again only when transects 5 through 13 were made. Field measurements were made, and samples were analyzed for nitrogen species, phosphorus, and major inorganic ions. All data collected from transect 1 through 6 and, for phytoplankton data through transect 9, are included in the discussion of conditions for 1969 70 (1969 71 for photoplankton). All remaining data are included in the discussion for conditions as of 1970 72. Unless otherwise specified, all field measurements and all water samples for chemical and biological analysis were collected just below the water surface. Plankton samples were preserved with formaldehyde (3- to 4-percent final concentration), copper sulfate (to help plankton to retain color), and detergent (to prevent coagulation). In addition to a "whole" water sample for quantitative plankton counting, a net sample (No. 12 plankton net) was obtained in some places for qualitative evaluation. Temporary wet mounts of sample concentrates were used for identification. Identification to species was made when possible, and counts are expressed as number of cells per milliliter. Benthic macroinvertebrate samples were collected with a 6 x 6 inch Ekman dredge. Two samples were taken at each point. Macroinvertebrates were separated using a 30-mesh sieve and were then preserved in 95 percent ethanol. Most organisms were identified, to generic or specific levels, and counts were expressed as numbers per square meter. ACKNOWLEDGMENTS The author gratefully acknowledges the assistance of several agencies and individuals in the collection and analysis of the water, sediment, and biologic samples. Mr. Lothian A. Ager, fisheries biologist, Florida Game and Fresh Water Fish Commission, Okeechobee, Florida, furnished and piloted the boat for the collection of samples, furnished valuable information on current conditions of the lake, and offered many suggestions for the study. Messrs. William M. Beck, Jr, and James L Hulbert, biologists, Florida Department of Polution Control collected, classified, counted, and made interpretations of bottom fauna. Jay R. Carver, chemist, Florida Department of Pollution Control assisted in the collection and chemical analysis of bottom sediments. The Environmental REPORT OF INVESTIGATIONS NO. 71 Protection Agency laboratory in Athens, Georgia, analyzed samples of water and bottom sediments for pesticides. Phillip Greeson, aquatic biologist, U. S. Geological Survey, counted and identified plankton in the samples obtained from the lake and assisted in the biologic evaluations. The investigation was made and the report was prepared under the general supervision of C. S. Conover, District Chief, U. S. Geological Survey, Tallahassee, Florida. DESCRIPTION OF LAKE OKEECHOBEE AND DRAINAGE SYSTEM HISTORY OF THE LAKE The Lake Okeechobee region was occupied by the Calusa Indians for about two centuries after Ponce de Leon's discovery of Florida in 1513. The Calusas were replaced by the Seminole tribe, which was formed during the 18th century by the amalgamation of immigrants from the Creek and Hitchiti tribes of Georgia and Alabama. Not until after the United States acquired the Territory of Florida in 1821 did white settlers push southward into the region. Military campaigns during the second Seminole Indian War (1835 42) led to the exploration of Lake Okeechobee. and the Everglades region. Before this, exploration was almost impossible because of Indian resistance and the almost impenetrable Everglades. In 1881 the channel of the Caloosahatchee River was extended to the lake. Drainage canals were later dug through the Everglades to the ocean, and dikes were constructed around the south shore of the lake for protection against floods. To increase the outflow capacity, the construction of the St. Lucie Canal to the ocean was begun in 1916; the canal reached full capacity in 1928. A low muck levee on the south and east sides of the lake, begun in 1921, was completed in 1924. This levee was overtopped and breached in 1926 and 1928 by hurrican-driven storm surges. The U. S. Army Corps of Engineers began construction of levees in the early thirties. Hurricane gate structures were built, several pumping stations have been completed, and others are near completion. The pumping stations alleviate flooding near the lake by pumping excess water into the lake. The lake stage ranges from about 11 feet during extreme drought to about 17 feet during extremely wet years, but generally fluctuates between 14.0 and 15.5 feet. PHYSICAL FEATURES Lake Okeechobee, within the Coastal Lowlands of Florida, is part of a plain, the Pamlico Terrace, that was formed by recession of the sea during the 10 BUREAU OF GEOLOGY late Pleistocene. It is the largest fresh-water lake within a single State; only Lake Michigan, of lakes entirely within the United States is larger. It is roughly trapezoidal and has an area of 720 square miles at a stage altitude of 15.0 feet. Its volume at this stage is 4,020,000 acre-feet. It is 35 miles long, north-south, and 30 miles wide. Currents can be fairly strong; the direction and intensity depend on amount of inflow, outflow, and pumpage into the lake, and on the wind. The average velocity of prevailing winds is approximately 9 mph, creating an average wave height of 1.4 feet. This height would result in effective mixing to a depth of 85 feet. The average depth of Lake Okeechobee is less than 9 feet. Wave height in excess of about 2 feet could cause effective mixing to virtually all depths, regardless of stage. TRIBUTARIES The streams and canals that are tributary to Lake Okeechobee north of the Caloosahatchee and St. Lucie Canals drain about 4,400 square miles. Of these, the Kissimmee River is the largest. It drains 67 percent of the inflow area and contributes about 75 percent of the tributary inflow to the lake. Fisheating and Taylor Creeks, Nubbin Slough, and Harney Pond and Indian Prairie Canals contribute most of the remaining 25 percent. The Kissimmee River drains 2,950 square miles, where altitude ranges from about 15 feet at Lake Okeechobee to more than 300 feet in Polk County. The lakes in the northern and western part of the basin constitute about 10 percent of the drainage area. The lower part of the Kissimmee River basin is relatively flat and is used extensively for large cattle ranches and some dairy farming. Channelization of the Kissimmee River from Lake Kissimmee to Lake Okeechobee began in April 1962 and was completed in July 1971. Several water-control structures have been installed, and the flow of the river is now completely regulated. Fisheating Creek originates in western Highlands County and flows southward into Glades County and then eastward to enter Lake Okeechobee at Lakeport. The creek meanders through cypress swamps, and the drainage boundaries are often indeterminate in the lower reaches. Runoff is sluggish because of the large amount of natural storage in the basin. Land in the Fisheating Creek basin is used for citrus groves, cattle ranches, and dairy farming. REPORT OF INVESTIGATIONS NO. 71 Taylor Creek, draining less than 200 square miles, enters Lake Okeechobee at its northernmost point. The. channel of the lower reaches of Taylor Creek is dredged for navigation to and from the lake through HGS-6 (Hurricane Gate Structure-6). The gate is open except during hurricanes and high lake stages. The land is used for cattle ranches and large dairy farms. Nubbin Slough is a small tributary originating in southwestern St. Lucie County and enters Lake Okeechobee 2-4 miles southeast of Taylor Creek. Harney Pond 'Canal is connected to Lake Istokpoga by Canal 41-A. The flow is from Lake Istokpoga through Canal 41-A into Harney Pond Canal (C-41), which enters Lake Okeechobee, about 4 miles northeast of the mouth of Fisheating Creek. The flow in Harney Pond Canal is completely regulated. Indian Prairie Canal, similar to Harney Pond Canal, is connected to Lake Istokpoga by Canal 41-A. The canal enters Lake Okeechobee from the northwest about 6 miles northeast of Harney Pond Canal. The flow is, completely regulated and is about one-quarter of that of Harney Pond Canal. DRAINAGE Before the levees were constructed on the south shore of Lake Okeechobee, natural outflow during wet periods spilled over the south shore into the Everglades, where it drained slowly through dense sawgrass to the sea. The outflow is now controlled through several canals, including the St. Lucie and Caloosahatchee canals. Small quantities of water are discharged through West Palm Beach, Hillsboro, North New River, and Miami Canals. St. Lucie Canal, the largest outflow canal, heads on the eastcentral shore and flows generally northeastward for about 40 miles to the ocean near Stuart (fig. 1). Its discharge is controlled at a lock and dam about 25 miles downstream from the lake. When the control level is normal, the only flow through the canal is from leakage and lockage and a small amount used for power generation at the lock and dam. Caloosahatchee Canal heads at HGS-1 on the southwest shore at Moore Haven (fig. 1), flows southwestward through Lake Micpochee, then through two locks in the channelized Caloosahatchee River before entering the estuary near Fort Myers. When the lake storage is at the normal control level, the only flow into the canal is from leakage and lockage through the navigation lock. West Palm Beach Canal heads at HGS-5 on the southeast shore about 8 miles south of the St. Lucie Canal. It extends southeastward for 19 miles and BUREAU OF GEOLOGY then eastward for about the same distance to enter the ocean at West Palm Beach. The canal is constructed through deep muck soil along the northern border of the Everglades. Its water is used extensively for irrigation during the winter vegetable-growing season. The Hillsboro and North New River Canals originate at S-2 (Pump Structure 2) and HGS-4 on the southeast shore, dividing 800 feet below HGS-4. The Hillsboro Canal flows through the winter vegetable-growing area and extends 51 miles to enter the ocean at Deerfleld Beach. The North New River Canal is the longest major canal in the Everglades, extending through its heart 60 miles to enter the ocean at Fort Lauderdale. These canals are used for irrigation and flood control. The North New River Canal is capable of carrying large quantities of water from Lake Okeechobee to the middle Everglades. Miami Canal heads at HGS-3 and S-3 on the southcentral shore. The canal is a continuous waterway, extending 81 miles south and east to enter the ocean at Miami. The central part of the canal, however, is blocked, and only the upper and lower reaches are effective waterways. HYDROLOGIC CHARACTERISTICS, 1969-70 Water enters Lake Okeechobee from rain falling directly on the lake, from tributaries, and sometimes from reverse, or negative, flow pumped from canals to remove flood water from the agricultural areas. The lake may also receive ground-water effluent: at the lake, the potentiometric surface of water in the Floridan aquifer is about 30 feet above land surface. Water leaves primarily through the St. Lucie and Caloosahatchee Canals and by evapotranspiration. Sometimes substantial quantities leave through West Palm Beach, North New River, Miami, and Hillsboro Canals and a very small amount by seepage through the levee along the south shore. PRECIPITATION The normal (median) rainfall over Lake Okeechobee is 45.60 inches per year (1,751,040 acre-feet). It varies from about an inch in November to more than 7 inches in June (U. S. Corps of Engineers, written commun., 1970). During the 19-month investigation, monthly rainfall was above the monthly normal (median) for 13 months and below for 6. Departures from normal (median) ranged from 2.82 inches below (60 percent of normal) to 9.85 inches above (480 percent of normal) in March 1970 when rainfall totaled 12.44 inches. The total amount of rain falling during the 19 months was 91.61 inches, REPORT OF INVESTIGATIONS NO. 71 20 inches (128 percent of normal) greater than the aggregate of the 19 monthly normals (medians). Figure 1A shows the rainfall for each month compared with the monthly normal (median) for each. Ld & RAINFALL, INCHES t O D of the 19-month span 8 8 = N Figure lA. Rainfall over Lake Okeechobee, January 1969 July 1970. INFLOW Of.the streams contributing water to the lake, the Kissimmee River is by far the largest. On the average, its contribution is about eight times greater than that of the next largest, Fisheating Creek, although its maximum daily flow of record is less. The following table lists the average discharge from each of several tributaries. 0 N I :I~f~ai~f55 -- ..., E ii .' I .4 :777777 .01 A tf ::::::::::::;:i::: E-11- :::::6:.::: BUREAU OF GEOLOGY Average Discharge Greatest daily average Tributary (cfs) (ac-ft/yr) Base period (cfs) (date) Kissimmee River a/ 2,188 1,584,000 1928-62 27,580 Oct. 3, 1969 Fisheating Creek b/ 264 191,100 1931-68 31,400 -- Harney Pond Canal 212 153,500 1962-68 2,910 -- Taylor Creek c/ 102 73,840 1955-68 6,930 -- Indian Prairie Canal 48.9 35,400 1962-68 1,470 -- Miami Canal 55.2 39,960 1957-68 -- - Nubbin Slough (d) -- -- - a/ Flow gaged at station S-65E; location on figure 1. b/ Flow gaged 14 miles upstream from State Highway 78. c/ Flow gaged 7.6 miles upstream from mouth. d/ Flow not gaged on continuous basis; small except during storms. OUTFLOW On the average, outflow from the lake through three major canals is about 2,500 cubic feet per second (1,830,000 acre-feet a year). The distribution, by canal, is as follows Average discharge Base Greatest daily average Canal (cfs) (ac-ft/yr) period (cfs) (date) St. Lucie 1,300 940,000 1952-68 11,430 March 27, 1970 Caloosahatchee 1,024 740,000 1938-68 8,290 April 10-11, 1970 West Palm Beach 173 125,200 1939-68 1,610 a/ a/ At times water flows into the lake from the canal; the daily maximum reverse flow in the period of record is 1,760 cfs. Seepage from the lake along its south shore is small in comparison with outflow through other means. According to Meyer (1971), the seepage along a 50-mile reach of shoreline is 22 cfs (cubic feet per second) at a lake stage of 14 feet and 50 cfs at a stage of 16.5 feet. The only remaining outflow element considered in this report is evaporation from the lake's surface. According to the U. S. Corps of Engineers (written commun., 1970) the normal (median) is 55.70 inches per year. Visher REPORT OF INVESTIGATIONS NO. 71 and Hughes (1969) report that in the vicinity of the lake the difference between rainfall and potential evaporation ranges from about zero or slightly less than zero (potential evaporation greater than rainfall) to 9 inches per year. WATER BUDGET, JANUARY 1969 JULY 1970 Rainfall during the investigation was considerably greater than normal (median), and for this reason the values of all the elements of inflow and outflow cited in the foregoing 2 tables, were substantially different from those of the 19-month study period. Inflow and outflow are summarized in table 3. Change of storage was computed by subtracting the capacity of the lake at the end of the study from that at the start. The lake was at a stage of 15.2 feet at the start and 14.1 feet at the end. On the basis of a rating table supplied by the U. S. Corps of Engineers, the difference was 480,000 acre feet. The "other sources" of table 3 represent unmeasured inflow and about 4 percent of the total budget. The amount, 359,000 acre-feet, is considered to have been contributed by sources not specifically known or determined, perhaps upward seepage from the Floridan aquifer (Parker and others, 1955). The amount could be represented, in part, by inaccuracies in the identified outflows or inflows. The average inflow from each stream during the 19-month period was substantially greater than the long-term average inflow because of the above-normal rainfall. A partial comparison follows: Source Percentage of average Fisheating Creek 142 aj Harney Pond Canal 130 Indian Prairie Canal 178 Kissimmee River 138 Taylor Creek 193 b_ aj On basis of flows at gaging station, 14 miles upstream from State Highway 78. .bJ On basis of flows at gaging station, 7.6 miles upstream from mouth. Outflows, similarly, were greater than the long-term averages. The flow in the St. Lucie Canal was 151 percent of the long-term average, in the Caloosahatchee Canal 282 percent, and in the West Palm Beach 121 percent of average. Table 3 Generalized Water Budget for Lake Okeechobee January 1, 1969 to July 31,1970 INFLOW OUTFLOW Q Total Q Total Soce cts acre-feet Source cfs acre-feet Fisieatlng Creek 562 643,000 St. Lucie Canal 1,960 2,240,000 Harnmy Pond Canal 275 315,000 West Palm Beach Canal 210 240,000 Indian Pairie Canal 87 99,200 Miami Canal 111 127,000 Kisimmes River 3,030 3,470,000 Calooshatchee Canal 2,890 3,310,000 Taylor Creek 279 320,000 Evaporation 88.01/ 3,420,000 Nubbin Slough 40 45,700 Change in Storage -1.1 3 -480,000 4/ North New River Canal 31 35,000 0 Pecipitaton 91.6 1/ 3,570,000 2/ OtherSources 187 359,000 TOTAL 8,857,000 TOTAL 8,857,000 If Inches; data supplied by U. S. Corps of Engineers. 2/ Based ona lake area of 730 sq mi 3 Feet; data supplied by U.S. Corps of Engineers SComputed from stage-volume rating table supplied by U. S. Corps of Engineers REPORT OF INVESTIGATIONS NO. 71 Usually, the Miami Canal contributes water to the lake on a long-term basis, but, during the 19-month period of investigation, it carried more water from the lake than into it. CHEMICAL AND PHYSICAL CHARACTERISTICS OF WATER AND SEDIMENT, 1969- 70 LAKE OKEECHOBEE The quality of the water in Lake Okeechobee varies with both location and time. Factors such as rainfall patterns, evaporation rates, and water use cause changes in the quality of the water with time. Probably the greatest factors influencing the areal variation in water quality are water movement and circulation patterns caused by varying amounts of inflow, outflow, and back pumpage of water into the lake from flooded agricultural areas. Characteristics of the water and bottom sediments of the lake are discussed under the following sections. The analyses on which the discussion is based are listed in table 13 (Appendix). Both physical and chemical parameters are tabulated, for samples collected during six sampling transects over a 19-month span from January 1969 through July 1970. Because chemical analyses by Holcomb (1968) and Duchrow (1970) extend the analytical record back to 1967, some of their analytical data are summarized in this report. PHYSICAL CHARACTERISTICS OF WATER In describing the water quality of Lake Okeechobee, specific conductance, temperature, dissolved oxygen, turbidity, pH, and color are classified as physical characteristics. Specific conductance is a measure of the ability of water to conduct an electrical current and is reported in micromhos per centimeter at 250C. It is a rapid determination and may be used to estimate dissolved solids or individual major chemical constituent in the water. For Lake Okeechobee, the ratios of eight chemical parameters to specific conductance are as follows: Dissolved solids (calculated from sum of dissolved constituents; see table 13 for explanation) 0.56 Calcium (Ca) .09 Magnesium (Mg) .03 Sodium (Na) .08 Potassium (K) .01 Bicarbonate (HCO3) .29 Sulfate (S04) .08 Chloride (Cl) .12 BUREAU OF GEOLOGY From these ratios the dissolved solids (calculated) or concentrations of the listed constituents can be estimated by multiplying a measured specific conductance by the ratio. For the six sampling transects,.average specific conductance ranged from 409 to 541 micromhos. The following table, prepared from data recorded by Holcomb (1968) and Duchrow (1970), summarized specific conductance extremes for 1967 70, on samples collected from the center of the lake: Micromhos Date Lake Stage (feet) Maximum 590 Feb., 1968 13.0 Minimum 330 Feb., 1970 15.5 During the present investigation, a sample from point 8, about 8 miles north of the center of the lake, at a stage of 15.9 feet, had a specific conductance of 199 micromhos, well below the 1967 70 minimum. Average water temperatures ranged from 120C in January 1970 to 300C in April 1970. The extremes were 9.0C and 340C (table 13). Vertical profiles at sites 1,6, and 11 on each sampling date showed no thermal stratification. Dissolved oxygen (DO) in water is derived from the atmosphere and from oxygen given off by aquatic plants. Solubility of oxygen in water varied inversely with temperature. Oxygen is removed from water by the respiratory process, by decomposition of organic material, by oxidation, and by release to the atmosphere when the water becomes supersaturated. During heavy biologic activity, DO may vary considerably diurnally. All DO measurements were made in-place during daylight. In general, concentration was lowest in the early morning and highest in mid-afternoon. DO was usually near saturation, and vertical profiles showed no DO stratification. A few measurements during periods of high biologic activity showed supersaturation. Extremes in DO were 59 and 11.2 mg/1. Average seasonal variation in DO, which is partly dependent on temperature, ranged narrowly from 7.1 mg/1 (92 percent saturation) in July 1970 to 9.9 mg/1 in January 1970 (92 percent saturation). Average areal variations in DO were low, ranging from 8.5 mg/1 (92 percent saturation) to 9.1 mg/1 (99 percent saturation), except at site 12 near the mouth of the St. Lucie Canal where average concentration was 7.4 mg/1 (81 percent saturation). Figure 2 shows how water temperature and DO varied seasonally. REPORT OF INVESTIGATIONS NO. 71 The lake water becomes very turbid during storm periods and is noticeably turbid even during extended periods of relative clam. Turbidity varied markedly with wind action. Apparently turbid water during storms is historical. Heilprin (1887) reported the water to be fairly clear when not disturbed but" .. .generally, however, it is tossed into majestic billows, which rake up the bottom, and bring to the surface a considerable infusion of sand, rendering the surface murky." For the lake transects, turbidity ranged from 7 to 56 JTU (Jackson turbidity units). Daily measurements at site 16 ranged from 1 to 59 JTU. The pH of a solution is a measure of the effective hydrogen-ion concentration. A pH value of 7.0 represents neutrality, whereas alkaline water has a pH greater than 7.0 and acidic water has a pH less than 7.0. The water in Lake Okeechobee is in a natural carbonate environment, which causes it to always be alkaline; field pH ranged from 7.8 to 9.0, with a median of 8.4. The pH was highest when photosynthetic activity in the lake was greatest, resulting in greater carbon dioxide uptake. Color of water gives a rough indication of the amount of dissolved organic material. Also, higher color usually indicates recent heavy inflow from streams and high lake stages. Color, as does turbidity, reduces light penetration in water and consequently has a regulatory effect over biologic processes. Water in the lake is generally much less colored than that of the tributary streams, possibly because of adsorption and flocculation of the colored organic matter by suspended material in the lake and by biochemical and photochemical oxidation. During normal lake stages, water color usually ranges from about 30 to 50 units on the Platinum-Cobalt scale, but the range is much wider from drought to flood periods. Average color intensity for the six lake transects ranged from 20 units in August 1969 and July 1970 to 70 units in January 1970. Color ranged from 5 to 120 units. The high color, at site 8, was caused by heavy inflow from the Kissimmee River. MAJOR CHEMICAL CONSTITUENTS Calcium, magnesium, sodium, bicarbonate, sulfate, and chloride are major dissolved chemical constituents in the water of Lake Okeechobee. Silica and potassium occur in lesser amounts. Figure 2 shows the average calculated dissolved-solids content for each of eight lake transects, two in 1940 41, and six in 1969 70. BUREAU OF GEOLOGY The lake water is generally more highly mineralized than inflowing water from any of the tributary streams. For example, calculated dissolved solids in the lake are two to three times higher than those in the Kissimmee River. Taylor Creek is probably the only exception; it at times contributes water much higher in mineralization than that in the lake. In February 1969 the calculated dissolved solids of Taylor Creek water was 605 mg/l, about double the concentration of the lake. In 1940 -41 Parker, Ferguson, and Love (1955) also noted that dissolved solids in the lake were about three times as great as those in the major tributary streams, and hardness was five to seven times as great as that of inflowing water. They mentioned several explanations for the higher mineralized water from the artesian Floridan aquifer, concentration from evaporation, and discharge into the lake of highly mineralized water from the West Palm Beach, Hillsboro, North New River, and Miami Canals during short rainy periods. They concluded, however, that the difference could be accounted for by dilute inflow water dissolving limestone formations on the bottom of the lake. This explanation is partly correct, although dissolved solids in the lake are concentrated somewhat from evaporation and there is a strong possibility that upward leakage from the Floridan aquifer occurs. The average potentiometric surface of the aquifer is more than 30 feet above the lake surface. A composition diagram of Lake Okeechobee, Kissimee River and Floridan aquifer waters suggest that some higher mineralized water from the Floridan aquifer may be entering the lake. The dissolution of limestone from the lake bottom would not account for the excess chloride, sodium, and sulfate, but a small input from the Floridan aquifer would. The flow of water into the lake by pumping from agricultural canals is small compared with the overall water budget for the lake, but this highly mineralized water does cause some increase in dissolved solids. This study shows that mineralization of the lake water varies inversely with lake stage and the amount of flushing from heavy runoff. As shown in figure 2, the average calculated dissolved-solids content in 1940- 41 was less than 190 mg/l, as compared with about 260 mg/1 in 1969 70. Increases in the concentrations of calcium, magnesium, sodium, chloride, sulfate, and bicarbonate were accordant. The smallest increase was in magnesium (2 mg/l), and the greatest was in chloride (20 mg/1). Sodium and sulfate increased 19 and 14 mg/l, respectively. In 1940- 41, when calculated dissolved-solids were less than 200 mg/l, annual average lake stages were 16.03 and 15.90 feet, respectively, whereas average lake stage from January 1969 to July 1970 was only about 15 feet. The highest average dissolved-solids content for the six transects of this investigation was during January 1969 (fig. 2) after a prolonged drought during which the lake stage had been below 12 feet. During the drought, evaporation and below-normal inflow and outflow concentrated dissolved solids REPORT OF INVESTIGATIONS NO. 71 remaining in the lake. After the above-average rainfall and flushing of the lake during this investigation, dissolved solids decreased significantly, from 309 mg/1 in January 1969 to 210 mg/1 in April 1970, near average for the 1940 41 sampling. Also, the July 1940 and July 1970 dissolved solids compare reasonably well. Areal variations in dissolved solids are generally smallest at low lake stages, when water movement is slow. At a lake stage of 14.2 feet in August 1969, calculated dissolved solids ranged from 253 mg/l at point 7 to 298 mg/l at site 15. For the five sites sampled in July 1970, also at a lake stage of 14.2 feet, calculated dissolved solids ranged from 227 mg/l at site 12 to 270 mg/l at site 5. DISSOLVED OXYGEN, MILLIGRAMS PER LITER DISSOLVED SOLIDS, MILLIGRAMS PER LITER 0o o 0 01 u MU AU D 0 E 01 5 ;- 3 1U1 MfSUOU 5 K --- --- ------ 1 r A . 031 1 WATER TEMPERATURE, DEGREES CELSIUS Figure 2. Average seasonal variations of dissolved solids, dissolved oxygen, and water temperature in Lake Okeechobee. BUREAU OF GEOLOGY Areal variation in dissolved solids are greatest at high lake stages, when water movement is fast. In January 1970 at a lake stage of 15.9 feet, calculated dissolved solids ranged from 110 mg/l at site 8 to 284 mg/l at site 13. Heavy inflow from the Kissimmee River largely influenced quality at site 8. The dissolved solids estimated from four specific conductance measurements of water collected from the center of the lake, reported by Holcomb (1968) and Duchrow (1970) from August 1967 to February 1970, ranged from 185 mg/1 at lake stage 15.5 feet in February 1970 to 330 mg/1 at lake stage 13.0 feet in February 1968. In this study the dissolved solids were 110 mg/1 at point 8 in January 1970. Site 8, as mentioned earlier, is about 8 miles north of the center of the lake. DISTRIBUTION OF NITROGEN AND PHOSPHORUS Nitrogen and phosphorus have long been considered to be key elements contributing to accelerated eutrophication of lakes. The concentrations of these two nutrients are vitally important in controlling the rate of biologic productivity; however, many other elements, some in trace quantities, are necessary for plant growth. When concentrations of inorganic nitrogen and phosphorus are high, algal blooms generally occur. Figure 3 shows the average concentrations for the various nitrogen species for the six lake transects made from January 1969 to July 1970. Total nitrogen (N) includes all forms of organic and inorganic nitrogen. Inorganic nitrogen in column A of figure 3 includes that from nitrate, nitrite, and ammonia. Average total nitrogen (N) concentration of 1.4 mg/1 was exactly the same for the three transects made in 1969. Inorganic nitrogen, however, was highest in January, but decreased in May and August when biologic activity in the take increased. A major part of the nitrogen in the lake is in organic form. During the six transects (fig. 3) organic nitrogen accounted for 71 to 93 percent of the total nitrogen and averaged 85 percent. Organic nitrogen is also the major nitrogen form in adjacent drainage basins. On the upper St. Johns River basin it accounts for about 90 percent of the total nitrogen (Goolsby and McPherson, 1970). The higher concentration of nitrogen in January and April 1970 to 1.7 mg/1 was caused by increased heavy inflow and abnormal rainfall. Table 8 shows that a considerable load of nitrogen can be contributed to the lake by rainfall. The rainfall over Lake Okeechobee was above normal from October 1969 through March 1970, when 12.44 inches (almost 10 inches above normal) fell. Average concentration of nitrogen in rainfall during January 1969 to January REPORT OF INVESTIGATIONS NO. 71 01 w I- w aJ z 0 2 n- 0 C- JAN MAY 1969 AUG JAN APR 1970 Figure 3. Average distribution of nitrogen (N) in Lake Okeechobee. JULY aqoqipaalO eMw (N) uawou o suo.pm.u posZsgm pro Iay 't amsld 3.0 EXPLANATION INORGANIC A JANUARY 1969 NITROGEN 9 MAY 1969 -(N C AUGUST 1969 TOTAL NITROGEN (N) D JANUARY 1970 ,ORGANIC NITROGEN E APRIL 1970 S(N) F JULY 1970 .0- W DATE S2.0 LOCATION see f g, I ) j .1.0 -. 0.... o00 0 S li 9 E tt 1ft 0 C A C BCa &Cl 2 3 4 5 6 7 8 9 10 II 12 13 REPORT OF INVESTIGATIONS NO. 71 1970 was 0.90 mg/l. Nitrogen in rainfall will be discussed in more detail in a later section. The low nitrogen concentration of 0.79 mg/l was caused by a phytoplankton bloom. Average nitrite and ammonia concentrations were generally low, (fig. 3) which indicates either the absence of gross cultural pollution or the effectiveness of DO in the lake to oxidize pollutants and to prevent the reducing condition necessary for in-place formation of nitrite and ammonia. In general, nitrogen concentration was lowest in the northern part of the lake, a little higher in the eastern part of the lake, and highest in the southern and western parts, as indicated by figure 4. Nitrogen concentration ranged from 0.51 to 2.9 mg/1. In general, inorganic nitrogen was highest during the winter and lowest during the summer, when biologic productivity was greatest. Inorganic nitrogen concentration ranged from zero to 1.1 mg/l. The high of 1.1 mg/l, at site 5 in April 1970, along with adequate phosphate ard other essential nutrients, may have triggered the large algae bloom at site 5 in July 1970, by which time inorganic nitrogen was zero, all having been utilized by the growing algae. Probably there is less circulation at site 5 than at any other place in the lake. The following table lists extremes in nutrient content of water samples collected from the center of the lake at four intervals, August 1967, February 1968, August 1969, and February 1970 (Holcomb, 1968; Duchrow, 1970). Minima Maxima Milligrams Milligrams Constituent Date per liter Date per liter Nitrate nitrogen Aug. 1967 0 Feb. 1968 0.1 Amonia nitrogen Feb. 1968 0 Aug. 1969 .04 Organic nitrogen Aug. 1967 .74 Aug. 1969 1.4 Orthophosphate (P04-P) Feb. 1968 .003 Feb. 1970 .052 Total phosphorus Aug. 1967 .016 Feb. 1970 .150 Average phosphorus concentration in the lake usually is lower than in the tibutary streams, which indicates phosphorus uptake in the lake. Large quantities of both nitrogen and phosphorus are assimilated by the large amount of vegetation in the lake. Much of the shallow part, especially in the west and northwest, contains heavy concentrations of grass and other aquatic vegetation. The vegetation releases the nutrients to the lake water or to bottom sediments on death. Dying vegetation, however, is continuously being replaced by new growth, which again requires large quantities of nutrients. Recycling of nutrients 26 BUREAU OF GEOLOGY between water and bottom sediments is a complex process, and further studies of the process are needed in Lake Okeechobee for a more definitive statement. In 1969 average total phosphorus concentration was low, from slightly less than 0.02 to 0.03 mg/1 (fig. 5). Orthophosphate (PO4-P) concentration ranged from 0.01 to slightly more than 0.02 mg/l and averaged 65 percent of the total phosphorus. Phytoplankton concentration for the 1969 lake transects was highest in May, resulting in assimilation of most of the orthophosphate. By January 1970, average total phosphorus (P) and orthophosphate (P04-P) had JAN MAY 1969 AUG JAN APR JULY 1970 Figue 5. Averge distribution of phosphorus (P) in Lake Okeechobee. REPORT OF INVESTIGATIONS NO. 71 increased, to 0.07 and 0.05 mg/l, respectively. The increased phosphorus concentration was in line with the increased nitrogen concentration in January 1970 and was also caused by abnormal rainfall and increased inflow to the lake in the fall and winter of 1969. The above-normal rainfall and inflow to the lake through March 1970 continued to contribute large loads of nutrients. Rain decreased in April, when only 0.01 inch fell on Lake Okeechobee. Areal and seasonal variations in phosphate concentrations are wide, as shown by figure 6. Areal variations are mostly caused by water-inflow changes and movement in the lake, and seasonal variations are caused by changes in biologic activity. Heavy inflow to the lake caused increased phosphate concentration and increased biologic activity causes decreased orthophosphate concentration. Total phosphorus concentration ranged from 0.01 to 0.15 mg/l; orthophosphate (P04-P) from 0.00 to 0.14 mg/1. The low and high concentrations of both orthophosphate and total phosphorus occurred at sites 7 and 8. EXPLANATION C O MGOST OUS LOCATION C UGUST 969 I 0 JANUARY 1>O %l E wAPRL IT70 AI I JULY 1OTT A a U Figure 6. Areal and seasonal variations of phosphorus (P) in Lake Okeechobee. crm l ....mu "' -" ~ ly ... 'Z- .. .. .. .. I--~ BUREAU OF GEOLOGY Phosphorus concentration was low in January 1969 because of low inflow rates to Lake Okeechobee before and during the sampling period, whereas high inflow rates in the fall and winter of 1969 flushed large loads of phosphorus into the lake. Sites 7, 8, and 9, where the concentrations were highest in January 1970, were directly influenced by heavy inflow from the Kissimmee River and Taylor Creek. On June 22, 1952, at a low lake stage of 12.81 feet, Odum (1953) reported phosphorus concentrations of 0.003 ppm (parts per million) and 0.007 ppm near the south shore of Lake Okeechobee and 0.03 ppm near the mouth of Taylor Creek. In February 1970 (p. 37) phosphorus in water from the center of the lake was the same as at site 8 in January of that year, 0.150 mg/l, the maximum for the present study. TRACE ELEMENTS In addition to nitrogen and phosphorus, many elements, some in trace quantities, are essential for plant growth. For the four lake transects from January 1969 to January 1970, samples were collected for spectrographic analyses for 25 trace elements at sites 1, 6, and 11. The results are given in table 4. Of the trace elements listed in table 4, nine (aluminum, boron, cobalt, copper, iron, manganese, molybdenum, vanadium, and zinc) have been listed by various investigators as essential for algal growth (Eyster, 1965; Provasoli, 1953, 1958; Walker, 1953; Gerloff and Skogg, 1957). All these elements are present, at least periodically, in Lake Okeechobee in varying concentrations, ranging from 1 pg/I (microgram per liter) for'molybdenum to 320 pg/1 for iron. All but three were present in more than adequate quantities for algal growth. The mean concentrations of boron (47 ig/l), copper (4pg/l), and manganese (< 3.3 ag/1) were less than minimum requirements for healthy algae growth of 100, (Eyster, 1965; Provasoli, 1958); 6 (Walker, 1953); and 5pg/l (Gerloff and Skogg, 1957), respectively. According to Holcomb (1968) a sample collected from the center of the lake in August 1967 contained zero chromium, manganese, nickel, and cobalt. PESTICIDES About 34 million pounds of pesticides were used in Florida in 1966 (Hifer and Kolipinski, 1970). Approximately 26 million pounds were applied on citrus fruits, vegetables, and melons. Less was used on other crops, on lawns, in homes, Table 4 Trace metal concentrations in Lake Okeechobee (ND, not detected; <, concentration less than value indicated) (Results in micrograms per liter) F. A5 E 5 1 E ^ I E 1 1-16-69 10 35 <2 <7 50 < 70 <7 <4 4 < 7 13 <7 3 <3 2 <7 3 <.7 820 <7 <7 <7 ND - 1 5-15-69 2& 45 <2 <3 55 < 75 <8 <8 3 <8 35 <3 4 <3 2 I 1-15-70 10 41 <.6 <3 53 < 60 <6 <6 2 ND < 3 19 <3 .3 <3 2 4 <.6 700 <6 <6 <3 <240 ND I a I - 6 1-14-69 30 34 <2 <7 47 < 70 <7 <4 4 <7 40 <7 3 <3 1 <7 3 <.7 930 <7 <7 <7 ND - 6 5-169 25 35 <2 <3 50 <60 <6 <6 7 < 6 75 <3 3 3 3 <9 4 <.6 670 <6 <6 <6 <250 - 6 8-27-69 14 55 < 3 <9 51 <130 <7 <7 3 <3 <13 6 <7 4 <3 2 <7 4 <.7 830 <9 <7 <7 <390 <13 6 1-13-70 20 55 <.6 <3 64 < 60 <6 <6 4 ND < 3 320 <3 .3 5 2 8 <.6 750 <6 <6 <3 <250 ND z 11 1-14-69 120 43 < 2 <8 54 < 80 <8 <5 9 < 8 160 < 4 5 2 <8 3 <.8 960 <8 <8 <8 ND - 11 5-14-69 15 40 <2 ,<3 50 < 70 <7 <7 3 < 7 70 <3 4 <3 2 <10 5 <.7 800 <7 <7 <7 <280 - 11 8-26-69 60 55 <3 <9 52 <130 <7 <7 2 <3 <13 14 <7 3 <3 2 <7 4 <.7 830 <9 <7 <7 <370 <13 11 1-13-70 80 41 <.6 <3 54 < 55 <6 <6 3 ND < 3 210 3 .3 5 2 6 <.6 650 <6 6 <3 <230 ND BUREAU OF GEOLOGY and for mosquito control. Citrus-fruit farming is intensive in the Lake Okeechobee inflow area, but the total amount of pesticides that enters the lake drainage is unknown. Winter vegetable farming and sugarcane growing is extensive south of the lake. As previously mentioned, excess water from these areas is pumped into Lake Okeechobee at HGS-3 and 4 to alleviate floods. DDT is applied to sweet corn for controlling army worms. Large acreage on the east and southeast shores of Lake Okeechobee is used for growing sweet corn in the winter. Toxaphene, another chlorinated hydrocarbon, is also applied to sweet corn for controlling corn earworms. Water and bottom-sediment samples from sites 1,6, 9, 11, 14, and 15 were analyzed for pesticides including seven chlorinated hydrocarbons, eight organophosphates, and the carbamate, sevin (table 5). The highest concentration of DDT series in the water was 0.09'pg/l and in bottom sediments 2,900 pg/kg (micrograms per kilogram). The highest concentration of toxaphene in bottom sediments was 1,400 pg/l. All the organophosphates and the carbamate listed in table 5 are used in the Lake Okeechobee area, but none were found in any of the water and bottom sediment samples, probably because of the nonpersistence of these pesticides. BOTTOM SEDIMENTS In the bottom sediments of Lake Okeechobee at most of the 15 sampling sites, appreciable quantities of iron, nitrogen, and phosphorus were present, but very little manganese (table 6). In general, the concentrations of nitrogen and phosphorus were lowest in the bottom sediments in the western part of the lake. This may be because of poor water circulation there or possible because of heavy vegetation than can assimilate these nutrients and prevent deposition to the sediments. Iron in the sediments ranged in concentration from 0.50 to 8.1 mg/g (milligrams per gram), total nitrogen ranged from 0.39 to 11 mg/g. The organic nitrogen was usually greater than 90 percent of the total nitrogen. The total phosphorus as P04 ranged from 0.08 (0.03 P) to 2.1 mg/g (0.69 P). TRIBUTARIES Nitrogen and phosphorus contents of streams and canals tributary to Lake Okeechobee are shown in figures 7 and 8, respectively and all data are shown in table 14. Figures 7 and 8 do not include data for Harney Pond and Indian Prairie Canals because water from them was usually not flowing into the lake during the Table 5 Pesticide analyses of water and bottom sediment for Lake Okeechobee (Results for water samples in pg/l (micrograms per liter), Bottom sediments pg/kg (micrograms per kilogram) ND (Not Detected) Chlorinated Date Hydrocarbons O(ganophosphates Carbamates WATER SAMPLES 1 1-16-69 0.02 ND ND ND ND ND ND ND ND ND ND ND ND ND ND ND 1 5-15-69 ND ND 0.06 " 1 8-27-69 ND " 1 1-15-70 " BOTTOM SEDIMENTS 1 1-16-69 82 74 180 ND ND ND ND ND ND ND ND ND ND ND ND ND 1 5-15-69 97 520 390 120 " 1 8-27-69 58 96 340 ND " 1 1-15-70 60 200 250 99 9 9 P 9 9 t 9 i WATER SAMPLES 6 1-14-69 0.02 ND ND ND ND ND ND ND ND ND ND ND ND ND ND ND 6 5-13-69 ND ND 0.09 9 " 6 8-27-69 ND " 6 1-13-70 0.02 9 " Table 5 Pesticide analyse of water and bottom sediment for Lake Okeechobee Continued (Results for water samples in pg/1 (micrograms per liter) Bottom sediments pg/kg (micrograms per kilogram) ND (Not Detected) So 2 1 z 0 BOTTOM SEDIMENTS 6 1-1469 9.9 11 ND ND ND ND ND ND ND ND ND ND ND ND ND ND 6 5-1369 ND ND "I "g i I. I It 6 8-27-69 t" I "" I 6 1-13-70 9 32 38 IS D ". " WATER SAMPLES 9 1-13-69 ND ND ND ND ND ND ND ND ND ND ND ND ND ND ND ND 9 5-1349 "." . 9 8-25-9 is " 9 1-12-71 .. .. .. .. .. BOTTOM SEDIMENTS 9 1-13-69 144 34 14 ND ND ND ND ND ND ND ND ND ND ND ND ND 9 5-13-69 64 140 380 120 " 9 8-25-69 150 ND ND " 9 1-12-70 27 100 32 "I "" Table 5 Pesticide analyses of water and bottom sediment for Lake Okeechobee Continued (Results for water samples in pg/I (micrograms per liter), Bottom sediments pg/kg (micrograms per kilogram) ND (Not Detected) Chlorinated Date Hydrocarbons Organophosphates Carbamates z N WATER SAMPLES 11 1-14-69 .03 ND ND ND ND ND ND ND ND ND ND ND ND ND ND ND 11 5-14-69 N D s i T I 9 9 t 9 . 11 8-26-69 " 11 1-13-70 " BOTTOM SEDIMENTS 11 1-14-69 14 6.4 11.2 ND ND ND ND ND ND ND ND ND ND ND ND ND 11 5-14-69 78 150 1900 200 "1 I" i . 11 .8-26-69 ND 120 ND ND I i " 11 1-13-70 6 19 WATER SAMPLES 14 1-16-69 ND ND ND ND ND ND ND ND ND ND ND ND ND ND ND ND 14 5-14-69 " 14 8-28-69 " Table 5 Pesticide analyses of water and bottom sediment for Lake Okeechobee Continued (Results for water samples in pg/l (micrograms per liter), Bottom sediments pg/kg (micrograms per kilogram) Chlorinated Date Hydrocarbons Organophosphatea Carbamates |z 0 BOTTOM SEDIMENTS 14 1-16-69 58 7.4 21 ND ND ND ND ND ND ND ND ND ND ND ND ND 14 5-14-69 11 14 250 9 .. i i i i 14 8-28-69 82 320 160 1400 " WATER SAMPLES 15 1-16-69 ND ND ND ND ND ND ND ND ND ND ND ND ND ND ND ND 15 5-14-69 " 15 8-28-69 " 15 1-13-70 I BOTTOM SEDIMENTS 15 1-16-69 97 214 226. ND ND ND ND ND ND ND ND ND ND ND ND ND 15 5-14-69 91 380 200 i 9 15 8-28-69 140 605 100 i i i i i . 15 1-12-70 61 250 325 ) " saue.nqq ul (N) uoSgoa!N "L xn sd A, FISHEATING CREEK B. KISSIMMEE RIVER C. TAYLOR CREEK D. NUBBIN SLOUGH INORGANIC NITROGEN ORGANIC NITROGEN Hr I- 5 5 LaL 2.0 i z. LI. (D 0 1O b ito in JAN FEB MAR APR MAY JUNE JULY AUG SEPT OCT NOV DEC JAN 1969 1970 i osaurnqe. u! (a) snzoqdsoqd "8 amfd > LWJ CA I- a o o |. Q2 - - 1 Co Q4 1969 1910 Ig6g 1g/o REPORT OF INVESTIGATIONS NO. 71 Table 6 Average chemical analyses of bottom sediments in Lake Okeechobee (Results in milligrams per gram, dry weight) Iron Nitrite & (Fe) Nitrate (N) Ammonia Organic Total Total (N) Nitrogen (N) Nitrogen (N) Phosphorus (PO4) 1 4.8 0.12 0.36 6.2 6.7 2.1 0.04 2 3.3 .50 .16 3.1 3.8 .83 .04 3 1.7 .00 .19 .48 .67 .13 .01 4 1.0 .00 .04 .40 .44 .27 .00 5 .50 .01 .04 .34 .39 .13 .00 6 .85 .01 .05 .44 .50 .08 .00 7 2.4 .01 .06 2.0 2.1 1.0 .00 8 1.0 .01 .04 .66 .71 .36 .08 9 7.2 .01 .14 9.2 9.4 .93 .00 10 6.7 .01 .15 10 10 .50 .02 11 6.3 .08 .14 8.7 8.9 .81 .01 12 4.0 .08 .17 4.2 4.4 1.0 .01 13 7.8 .14 .31 9.4 9.8 1.6 .00 14 .8 .02 .18 11 11 1.0 .00 15 8.1 .03 .22 7.5 7.8 1.8 .01 monthly sampling periods. Analyses of water standing in the channels of both are included in table 14. The high color of the water in Fisheating Creek is caused by organic material contributed by the dense swamps through which the stream flows. Dissolved solids (calculated) ranged in concentration from 51 to 119 mg/1. Generally the difference between dissolved solids (calculated) and dissolved solids (residue) represents organic material (table 14). The low mineral content of the water is caused by a lack of soluble mineral matter in the drainage basin. The total nitrogen load (N) contributed to Lake Okeechobee by Fisheating Creek from January 1969 through January 1970 is estimated to have averaged 2.0 tons per day. Average concentration was 1.4 mg/l. The average total phosphorus concentration (P) was 0.069 mg/1 and the load averaged 0.09 ton per day. There was a tendency for the DO in water of Fisheating Creek to sag during high flow, probably because of oxidation of organic materials that were washed in by flood waters. The low DO concentration of 3.3 mg/l (43 percent of saturation) in August (table 14) was probably caused both by oxidation of Manganese (Mn) BUREAU OF GEOLOGY organic material in the stream and high water temperature. Most of the DO measurements for Fisheating Creek were made in mid or late afternoon. In water from Hamey Pond Canal, average concentration of total nitrogen was 1.2 mg/l, daily load 0.92 ton. Average total phosphorus concentration was 0.072 mg/1 and the daily load averaged 0.06 ton per day. The total nitrogen (N) concentration in water of Indian Prairie Canal averaged 1.6 mg/1. The average daily load was 0.42 ton per day, less than half that of the Harney Pond Canal because of the smaller discharge of the Indian Prairie Canal. The sample collected in March (table 14) contained 0.058 mg/l nitrite-nitrogen and 0.76 mg/1 ammonia-nitrogen, which may indicate some form of pollution. Average total phosphorus concentration was 0.081 mg/l, and the average daily load was 0.02 ton, less than half that of the Harney Pond Canal. Water in the Kissimmee River (although colored) is less mineralized than that of any other stream and canal tributary to Lake Okeechobee except Fisheating Creek, and is of excellent chemical quality. Calculated dissolved solids average 108 mg/l. Even though the mineral content is low, the river contributes the greatest load of dissolved solids to Lake Okeechobee, 1,010 tons per day. This, of course, is because of the large discharge of the Kissimmee. The total nitrogen (N) concentration in water of the Kissimmee River averaged 099 mg/l, lower than in any other stream and canal tributary to Lake Okeechobee. Because of the large discharge, however, the total nitrogen load of 9.22 tons per day was the highest. Average total phosphorus concentration was 0.078 mg/1, and the daily load averaged 0.73 ton, which was the greatest load entering Lake Okeechobee. DO ranged from 4.9 mg/1 (66 percent saturation) to 10.1 (103 percent saturation). The lower concentrations occurred in the summer, when both water temperature and flow were seasonally high. Odum (1953) reported for a sample collected from the Kissimmee River on June 22, 1952, a total phosphorus (P) concentration of 0.012 ppm. The average discharge of the river on that date was 1,450 cfs. These measurements indicate that the total phosphorus load of the Kissimmee River on June 22, 1952, was only 0.052 ton per day. The water contributed to Lake Okeechobee by Taylor Creek is often high in dissolved solids, sodium, sulfate, and chloride and is almost always high in nutrients, especially phosphorus. The high color of the water, ranging from 40 to 220 units, is probably caused by the natural swampy environment through which the stream flows. REPORT OF INVESTIGATIONS NO. 71 Average dissolved-solids content (calculated) for the 13 monthly samples collected was 249 mg/l. At other times, dissolved-solids content (calculated) of water in Taylor Creek has been much greater because of contributions from Williamson Ditch, a tributary. Total nitrogen (N) concentration in water from Taylor Creek averaged 1.6 mg/1, and the load contributed to Lake Okeechobee averaged 1.39 tons per day. Ammonia-nitrogen concentration was always high, ranging from 0.086 to 0.44 mg/l. Average phosphorus concentration in water from Taylor Creek was higher than that in any other water in the Lake Okeechobee drainage system during the period of study. Average total phosphorus concentration was 0.62 mg/1, and the daily load was 0.54 ton per day. Taylor Creek contributed less than 10 percent as much water to Lake Okeechobee as the Kissimmee River during the investigation, but its contribution of phosphorus was 75 percent of that discharged by the Kissimmee. Odum (1953) reported a total phosphorus concentration of only 0.057 mg/l in water from Taylor Creek on June 22, 1952. Nubbin Slough contributed only about one-half percent of the total inflow to the lake during the investigation, but its nitrogen and phosphorus contribution was high, relatively. Total nitrogen (N) concentration averaged 2.0 mg/1, highest observed in the drainage system, excepting the North New River Canal. Total nitrogen load, however, averaged only 0.25 ton per day because of the small discharge. Most of the inorganic nitrogen in Nubbin Slough water was in the form of ammonia nitrogen, averaging 0.66 mg/1. Total phosphorus concentration in Nubbin Slough water averaged 0.36 mg/1, second only to Taylor Creek. The average daily load of 0.05 ton per day, however, was relatively low because of the small discharge. Average DO concentration in Nubbin Slough water ranged from 1.0 mg/1 (11 percent of saturation) to 9.4 mg/l (124 percent of saturation). The low concentrations were caused by the use of large quantities of oxygen for decomposition of organic substances. The supersaturated concentrations were caused by oxygen-producing photosynthesis triggered by the availability of nutrients for biological activity. DRAINAGE CANALS The drainage canals were sampled only when water was moving to or from the lake. Excellent data were obtained from the St. Lucie Canal and relatively good data from West Palm Beach, North New River, and Caloosahatchee Canals BUREAU OF GEOLOGY (table 15). Only three samples, however, two where flow was positive and one where flow was negative, were obtained from Miami Canal. The quality of water in the drainage canals is generally similar to that of the lake water during positive flow (flow from the lake). During negative-flow, when water is either flowing or being pumped into the lake through HGS-3 at pump structure 3 or HGS4 at pump structure 2, the quality of the water in the North New River and Miami Canals deteriorates rapidly. Dissolved solids, nutrients, and other major constituents increase to concentrations often exceeding State water-quality standards. Also, dissolved oxygen concentration frequently sags to below 5.0 mg/1 and' less than 50 percent saturation. Water pumped into the lake from the agricultural areas is the poorest in quality of any other entering Lake Okeechobee. Dissolved solids ranged from 163 mg/ in the Caloosahatchee Canal during positive flow to 1,160 mg/l in the North New River Canal during negative flow. The negative-flow sample from the North New River Canal also contained high concentrations of sodium (239 mg/1) and chloride (332 mg/1), in excess of the State standards of 250 mg/1. Dissolved oxygen was 4.0 mg/l, or 43 percent of saturation. Total nitrogen concentration was 3.8 mg/1, of which 2.0 mg/l, or 53 percent, was organic nitrogen. The 1.8 mg/l inorganic nitrogen consisted of 1.0 mg/l NO3-N, 0.08 mg/1 NO2-N, and 0.72 mg/l NH4-N. The high concentrations of nitrite and ammonia may indicate pollution. The highest phosphorus concentration was in a positive-flow sample from the North New River Canal in January 1970. Orthophosphate was 0.19 mg/1 as P, and total phosphorus was 0.20 mg/l. Water in the drainage canals has a high color, exceeding 150 units, during negative flow, which indicates that large quantities of organic matter are pumped from the agricultural areas into the lake. The color of water flowing directly from the lake was usually no more than 30 units. NITROGEN AND PHOSPHORUS IN RAINFALL Rainfall contributes large quantities of nutrients to Lake Okeechobee. In order to assess nitrogen and phosphorus contributed by rainfall, samples were collected at HGS-1 (Moore Haven Lock) from January to December 1969. An aliquot from each period of rain was collected to obtain an adequate sample for one analysis each month. The results of the analyses are given in table 7. The results do not include dry fallout inasmuch as the sample-collection apparatus was covered except during rainfall periods. About 75 percent of the total rainfall during 1969 was sampled. The rainfall at HGS-1 was about 10 inches greater than the average rainfall of 54.47 inches measured for the lake in 1969. REPORT OF INVESTIGATIONS NO. 71 Table 7 Nitrogen and Phosphorus in Rainfall at Hurricane Gate Structure-1 (Results in milligrams per liter except for rainfall which is in inches and specific conductance which is in micromhos at 250C) o DATES 1969 .| ___ M g II ii t 2 I January 4, 5, 6 1.19 25 0.07 0.009 0.10 0.25 0.43 0.007 0.007 February 16 1.51 26 .05 .003 .00 .20 .25 .007 .029 March 3, 8 1.06 21 .11 .003 .09 .24 .44 .003 .007 March 8, 9, 13, 17 3.70 29 .1 .006 .12 .25 .48 .003 .013 March 26, 31; April 2, 11, 29 and May 2, 3, 15 2.33 47 .3 .000 .12 .45 .87 .036 .055 June 14, 15, 16, 17, 20 5.89 60 .02 .000 .41 .24 .67 .020 .029 June 21, 28; July 3, 11, 14, 18 20, 21, 22, 27, 28, 29 5.38 80 .02 .003 .06 .40 .48 .013 .020 August 2, 4, 5, 6, 7, 8, 11, 12, 13, 14, 16, 18, 25 7.54 80 .1 .006 .12 .35 .58 .007 .026 September 24, 27, 29, 30; October 1, 2, 3, 6, 19, 20, 22, 23, 24 12.17 17 .2 .000 .85 .58 1.6 .11 .13 October 30; November 10, 14 3.93 29 .07 .009 .85 .52 1.4 .055 .091 December 8, 10, 11 3.40 14 .0 .003 .04 .58 .62 .000 .016 Rainfall weighted averages l/ 48.10 43 .10 .003 .38 .42 .90 .040 .056 1/ Total rainfall in samples analyzed. BUREAU OF GEOLOGY Table 7 shows wide variations in the measured constituents. Specific conductance ranged for 14 to 80 micromhos, total nitrogen from 0.25 to 1.6 mg/l, and total phosphorus ranged from 0.007 mg/l in January and March to 0.13 mg/1 in September and October. The rainfall in the summer and fall apparently contains higher nutrient concentrations than it does in winter and spring. At times the concentrations of nitrogen and phosphorus in rainfall are comparable to concentrations found in tributary inflow and in the lake. The concentration of total phosphorus in rainfall average 0.056 mg/l, equivalent to the average concentration in Lake Okeechobee during 1969 70. The concentration of total nitrogen in rainfall averaged 0.90 mg/l, which was approximately 50 percent of the average concentration in Lake Okeechobee during 1969 70. The average nitrogen and phosphorus values reported in table 7 compare favorably with results from other studies (see table below): Analyses of Rainfall (Results in Milligrams per liter except specific conductance) Source A B C D Specific conductance (micromhos at 25C) 43 10-30 Nitrate (N03-N) 0.10 0.20 0.09 0.13 Nitrite (NO2-N) .003 .006 -- .00 Ammonia (NH4-N) .38 .21 .18 .07 Organic nitrogen (N) .42 .32 Total nitrogen (N) .90 .74 .43 Orthophosphate (PO4-P) .040 .026 Total phosphorus (P) .056 .033 .059 A. Hurricane Gate Structure 1, Lake Okeechobee (average of 11 analyses, January to December 1969). B. Brezonik, P. L., Morgan, W. H., Shannon, E. E., and Putnam, H. D., 1969 (Average rainfall analyses in north central Florida, 1968). C. Schneider, Robert F., and Little, John A., 1969 (Average of 3 rainfall samples in central Florida, 1969). D. Gambell, Arlo W., and Fisher, Donald W., 1966 (Average monthly analyses of rainfall in eastern North Carolina and southeastern Virginia, August 1962 to July 1963). REPORT OF INVESTIGATIONS NO. 71 WATER-QUALITY BUDGET, 1969 70 A water budget for Lake Okeechobee for the 19-month span January 1, 1969 to July 31, 1970 is presented in table 3. A water and dissolved-solids budget for the 13-month span January 1, 1969, to January 31, 1970 is shown in table 8. The dissolved-solids budget could not be extended to July 1970 because data collection for tributaries and drainage canals was terminated in January 1970. Inflow water from major water sources for the 13-month period failed to balance the measured outflow by 180,800 acre feet, 2.8 percent of the total water budget. This amount is indicated under the "inflow" column (table 8) as being from other sources and, as mentioned in the 19-month budget, may be from upward seepage from the Floridan aquifer. The dissolved-solids budget shown in table 8 was computed from average dissolved-solids content in the inflow and outflow water. Average dissolved- solids content in precipitation was computed by multipling the average specific conductance of 43 (table 7) by 0.65, which is considered to be the average factor for conversion of specific conductance of rainfall to dissolved solids (U. S. Geological Survey, Water Resources Data for Florida, 1968, part 2, water quality records, p. 8). The computed factor for the lake water was 0.56. The change in storage for dissolved solids was computed from the difference in the total tons in the lake in January 1969 and January 1970. The inflow of dissolved solids in table 8 failed to balance the outflow by more than 250,000 tons, or approximately 20 percent of the dissolved-solids budget. This 250,000-ton residual may result, in part, from cumulative errors in measurements and, in part, from pickup of dissolved solids by the outflow waters. The most probable explanation for pickup of dissolved solids in the outflow water is solution of limestone from the lake bottom and resolution of dissolved solids previously trapped in the sediments. Most lakes act as sinks to trap part of the dissolved solids entering from tributaries, especially at low flow, as part of natural eutrophication. For example, Oneida Lake in New York State traps 11 percent of the dissolved solids (Greeson, 1971). TABLE 8 Generalized water and dissolved solids budget for Lake Okeechobee, January 1, 1969 to January 31, 1970 INFLOW OUTFLOW Dissolved Solids Dissolved Solids Q Total Total Q Total Total Source cfs Ace-ft. Mg/1 tons/day tons Source cfs Acre-ft. mg/l tons/day tons Fisheating Creek 529 415,000 73 104 41,000 St. Lucie Canal 1,700 1,340,00 1,330 525,000 Harney Pond Canal 286 224,000 151 116 46,000 W.P. Beach Canal 218 171,000 310 182 72,000 Indian Prairie Canal 84 66,100 169 37 14,700 N. New River Canal 311 244,000 451 378 150,000 Kissimmee River 3,450 2,710,000 108 1,010 398,000 Miami Canal 351 276,000 356 337 134,000 Taylor Creek 322 253,000 249 214 84,800 Caloosahatchee Cnl 2,386 1,870,000 246 1,584 627,000 Nubbin Slough 46 36,100 167 20 7,940 Evaporationj/ 57.14 2,220,000 - N. New River Canal 213 167,000 893 512 203,000 Change in StorageJ/ 0.5 240,0004/ -833 -330,000 Miami Canal 62 49,000 642 108 42,800 Precipitationj/ 58.09 2,260,000.2/ Other Sources 49 180,000 TOTALS 6,361,000 2,978 1,178,000 TOTALS 6,361,000 2,978 1,178,000 1/ Inches; data supplied by U. S. Corps of Engineers 2/ Based on a lake area of 730 sq mi 3/ Feet; data supplied by U. S. Corpsof Engineers 4/ Computed from stage-volume rating table supplied by U.S. Corps of Engineers REPORT OF INVESTIGATIONS NO. 71 Interestingly, precipitation during the 13 months contributed 30 percent of the nitrogen entering Lake Okeechobee, second only to the Kissimmee River, which contributed 39 percent. The concentration of nitrogen in water from the Kissimmee was only a little greater than that in rainfall (table 9). Catfish bait used by commercial fishermen was thought to be an important source of nutrients to the lake, but only 0.20 percent of the 6.75 tons per day of the cottonseed and soybean meal cake used for bait is soluble nitrogen. Nitrogen in catfish bait and the commercial fish harvest is small compared with the total nitrogen budget. Ager (1970) estimated that the annual commercial fish harvest could be increased to 34,200,000 pounds per year, dressed weight. The rough weight (undressed) would be about double, or 94 tons per day, which would increase the estimated nitrogen removal from the lake from 0.02 ton per day to 0.56 ton per day, or 222 tons for the 13-month budget and the amount retained in the lake would decrease to about 20 percent of the total nitrogen budget. Table 9 shows that 2,080 tons or 22 percent, of the nitrogen was trapped in the lake. Lakes naturally act as sinks and trap nitrogen. For example, approximately 20 percent of the nitrogen entering Oneida Lake, New York, is trapped, (Greeson, 1971). Taylor Creek contributes only 4 percent of the water to Lake Okeechobee (table 8) but contributes 26 percent of the total phosphorus load, the second largest source (table 10). The Kissimmee River contributes 36 percent of the total phosphorus load. Precipitation, the third major source, contributes 21 percent. The largest value on the outflow side of the phosphorus budget was 295 tons, or 36 percent, trapped in the lake for the 13- month period. In Oneida Lake, New York, 62 percent of the phosphorus entering is trapped (Greeson, 1971). The change is storage of 277 tons of phosphorus was the second largest value on the outflow side of the budget. The phosphorus concentration in January 1969 was 0.02 mg/1 and in January 1970 was 0.07 mg/l. BIOLOGICAL CHARACTERISTICS OF LAKE OKEECHOBEE, 1969- 71 PHYTOPLANKTON Of about 90 samples collected between January 1969 and April 1971 for determination of phytoplankton content, 14 had more than 5,000 cells/ml and 5 had more than 100,000 cells/ml, as shown in the following table and table 16 in the appendix. The estimated average number of cells per milliliter for 6 sites in January 1971 was 149,630 cells/ml, and the maximum number was 473,700 cells/ml from site 5. Table 9 Generalized nitrogen (N) budget for Lake Okeechobee January 1, 1969 to January 31, 1970 INFLOW OUTFLOW Q Nitrogen Q Nitrogen Source cfs mg/l tons/day total tons Source cfs mg/1 tons/day total tons Fisheating Creek 529 1.4 2.00 792 St. Lucie Canal 1,700 1.2 5.53 2,190 Harney Pond Canal 286 1.2 .93 367 West Palm Beach Canal 218 1.3 .76 302 Indian Prairie Canal 84 1.6 .36 144 N. New River Canal 311 1.5 1.26 498 Kissimmee River 3,450 .99 9.22 3,650 Miami Canal 351 1.1 1.04 413 Taylor Creek 322 1.6 1.39 551 Caloosahatchee Canal 2,396 1.1 7.07 2,800 Nubbin Slough 46 2.0 .25 98 Change in Storage 2.65 1,050 N. New River Canal 213 3.8 2.18 864 Commercial Fish H. 4 3.05./ .6 .02 8 Miami Canal 62 1:6 .27 107 Trapped in lake 5.25 2,080 PrecipitationJ/ 58.09 .90 6.98 2,760 Catfish Bait2/ 6.75j/ .20 .01 4 TOTALS 23.59 9,340 TOTALS 18.33 7,261 *, 'J Inches S2 Tons per day 3 Percent of soluble nitrogen (N) Dressed weight 1.45 T/day S5/ Percent nitrogen (N) INFLOW OUTFLOW Q Phosphorus Q Phosphorus Source cfs mg/I tons/day total tons Source cfs mg/I tons/day total tons Fisheating Creek 529 0.068 0.09 39 St. Lucie Canal 1,700 0.062 0.29 113 Harey Pond Canal 286 .072 .06 22 West Palm Beach Canal 218 .033 .02 8 Indian Prairie Canal 84 .082 .02 7 N. New River Canal 311 .026 .02 9 Kissimmee River 3,450 .078 .73 289 Miami Canal 351 .020 .02 8 Taylor Creek 322 .62 .54 213 Caloosahatchee Canal 2,390 .039 .25 99 Nubbin Slough 46 .36 .05 18 Change in Storage .70 277 N. New River Canal 213 .18 .10 40 Commercial Fish Har .2 3.0 - Miami Canal 62 .036 .01 3 Trapped in Lake .74 295 Precipitation/ 58.09 .056 .43 170 Catfish Bait / 6.75./ .29 .02 8 TOTALS 2.04 809 TOTALS 2.04 809 ./ Inches 2/ Tons per day / Percent of soluble phosphorus (P) Table 10 Generalized Phosphorus (F) Budget for Lake Okeechobee January 1, 1969 to January 31, 1970 -I 0 0 z 0 -2 . i, BUREAU OF GEOLOGY Numbers of phytoplankters in cells per milliliter in Lake Okeechobee, January 1969 to April 1971. Maximum and minimum not determined when cells per milliliter were less than 50. Date Average Number Maximum Minimum No. of sites January 1969 Less than 50 Less than 50 Less than 50 15 May 1969 1,220 4,600 100 15 August 1969 Less than 50 Less than 50 Less than 50 15 January 1970 Less than 50 Less than 50 Less than 50 15 April 1970 1,560 7,500 Less than 50 7 July 1970 32,300 106,800 60 6 October 1970 25,400* 108,500* 2,100 6 January 1971 149,630* 473,700* 960* 6 April 1971 7,956* 37,400* 80* 8 Estimated. In general, the highest concentrations of phytoplankton were observed in the western and northern parts of the lake. Concentration was high at site 5 in the western part of the lake except in April 1970 and April 1971. In April 1970 a sample was taken from the Kissimmee River in addition to those collected from the lake. The phytoplankton count in the sample from the Kissimmee was greater (7,700 cells/ml) than in any of the lake samples of that month. Possibly algal blooms were then occurring in one or more of the lakes drained by the Kissimmee. At site 12, also in April 1970, at the mouth of the St. Lucie Canal, the count was 7,500 cells/ml. In April 1971 the maximum count was at site 8 (37,400 cells/ml) and 9 (15,900 cells/ml), both in the northern part of the lake. Genera and species of phytoplankton observed in Lake Okeechobee are listed in table 11. Pediastrun simplex, a green alga typical of very early eutrophic lakes, was abundant in Lake Okeechobee in January, May, and August 1969 and in January 1970. Other codominant species present with Pediastrum simplex during this period were: Oscillatoria cortina (January 1969, August 1969); Melosira sp. (January 1969 and 1970); Mongeotia sp. (January 1969 and 1970); Merismopedia elegans (May 1969); Microcystis aeruginosa (August 1969); and Aphanizomenon holsaticum (August 1969). Microcystis aeruginosa and Aphanizomenon holsaticum are both potential nuisance forms of blue-green algae that often grow abundantly during late summer when temperatures are at a maximum. When conditions are favorable, these species form dense growths that tend to float and thus interfere with recreational utility of lakes. Both forms can spoil water for domestic uses, swimming, and recreation, and often cause the death of fish in heavily infested REPORT OF INVESTIGATIONS NO. 71 Table 11 Phytoplankton observed in Lake Okeechobee (A, abundant; P, present; -, not present) Average water temperatures (0C) 15 26 29 12 CHLOROPHYTA (Green algae) Closterium parvulum P P - Closterium pronum P - Mougeotia sp. A A Pediastrum Boryanum P - Pediastrum duplex P P P Pediastrum integrum P - Pediastrum simplex A A A A Pediastrum tetras P - Scenedesmus bijuga- - Staurastrum sp. P P - CHRYSOPHYTA (Yellow-brown algae including diatoms) Cyclotella sp. p - Melosira sp. A P A Stephanodiscus sp. P - Synedra sp. P P P Tabellaria sp. P - 30 30 27 22 27 A P P P P P P P P P A - P A P P - PYRROPHYTA (Dinoflagellates) Ceratium hirundinella CYANOPHYTA (Blue-green algae) Anabaena Circinalis Anabaena flos-aquae Aphanizomenon holsaticum Lyngbya contorta Merismopedia elegans Microcystis aeruginosa Oscillatoria cortina (?) Spirulina sp. P - P P - A - A P - - A P A P A A SA A P P A A A A P A A P P P P A P A P P P P A P P P P A P a, Ch ~ q C h 0 0 0 4 ". tz to 4j Or PI ;c 80~ ~ ~il 4Mas -0, 99 BUREAU OF GEOLOGY lakes. When detected during August 1969, however, concentrations of both forms in the lake were far below nuisance levels. After January 1970, Pediastrum simplex was replaced as the dominant alga at most points by Aphanizomenon holsaticum. The increased concentration of phytoplankton to bloom levels and the change of dominant species from green to blue-green algae after January 1970 followed a period of heavy inflow from rainfall and tributaries, with consequent increased influx of nutrients. The rapid seasonal changes in phytoplankton population reflect a change in the environmental conditions within the lake. In April 1970 and 1971, Aphanizomenon holsaticum dominated samples collected from the northern part of the lake. In July 1970 and January 1971, Aphanizomenon holsaticum was the most numerous alga at all except site 2, and in October 1970 it was the dominant species at half the sites. Other dominant alga included: the diatoms (Cyclotella sp. April 1970 at sites 2, 5, and 15 and July 1970 at site 2) and Stephanodiscus niagarae (April 1971 at site 2); the green algae, Closterium sp. (codominant in January 1971 at site 2 with Aphanizomenon holsaticum) and Pediastrum simplex (April 1971 at site 5); and the blue-green algae Merimopidia elegans (October 1970 at sites 2 and 12);Spiruhna sp. (October 1970 at site 8 and April 1971 at sites 12 and 15); and Anabaena flos-aquae (April 1971 in the Kissimmee River). Concentrations of Aphanizomenon holsaticum far exceed the numbers of other alga, with the exception of a single sample collected by the Florida Game and Fresh Water Fish Commission in a plankton bloom on June 29, 1970. The phytoplankters in this bloom were represented almost exclusively by Anabaena flos-aquae, which numbered 595,600 cells/ml. Although large blooms ofAphanizomenon holsaticum occurred during July and October 1970 and January 1971, most specimens were small. This may indicate that nutrient conditions in the lake were favorable for reproduction but unfavorable for optimum growth. Growth of phytoplankton in the lake may be limited by high turbidity. Secchi disc readings were generally less than 1.0 foot. The high turbidity results from finely suspended sediment. Lake Okeechobee has an average depth of about 9 feet, and mixing, in which sediment is constantly resuspended from the bottom, is effective. BENTHIC ORGANISMS Average number of benthic macroinvertebrates in sediment samples collected in January, May, and August 1969 and in January 1970 at seven sites REPORT OF INVESTIGATIONS NO. 71 Table 12 Average number of bottom organisms per square meter January, May, August 1969, and January 1970 (Determinations made by Florida Department of Air and Water Pollution Control) Point Organisms 1 5 6 8 9 11 15 Oligochaeta Gammarus sp.' Hyalella azteca Cyathura polita Taphromysis sp. Coelotanypus sp. Procladius sp. Chironomus crassicaudatus Glyptotendipes lobiferus Glypotendipes paripes Tanytarsus sp. Cladotanytarsus sp. Polypedilum sp. Chaoborus sp. Viviporus sp. Melanoides sp. Unid. snail 301 602 150 898 935 ...X 37 -XXX -X- 124 X-X. 210 -X- -x. .-'- 21 -XX 494 XX.. 10 XX- 199 ..XX 16 -X-X 59 XXXX 5 X- 5 -X- 5 X- 102 X-X- 48 -X- 11 -X- 226 XXX. 48 -.-X 75 -XX 5 -X- 166 .-.X 16 -X- 5 X- XXX. 43 -.-X 118 XX-X 252 .XXX 215 -.- 16 X- 5 -X- 1,774 Totals 1,332 954 541 950 1,569 5,433 SDominant species sampled at site for date indicated. ; Present X ; Not present ; Position indicates date of collection: January, May, August, January XX.. 16 -X.- 32 -XXX 269 X.-X 575 .-X- 11 X- 64 XXXX XXXX 5 -X 5 -X- 640 XXXX 220 -XX 16 X- 5 -X 4,392 ,.... 10 X-X 16 -X 399 XXXX 5 X- 11 -X 328 -xx 107 -XXX BUREAU OF GEOLOGY in Lake Okeechobee ranged in number from 541 per m2 (square meter) at site 6 to 5,433 m2 at site 11 (table 12). The average for all sites was 1,794 per m2. Highly enriched lakes in central Florida support numbers ranging from thousands to tens of thousands per square meter. Numbers in excess of 10,000 are often indicative of organic pollution. Macroinvertebrates were most numerous in the northern, eastern and central parts of the lake, at sites 9, 11, and 15, respectively. At these sites bottom samples were mud; at other sites, samples were sand, or shell mixed with mud. Mud usually supports larger standing crops of benthic animals than sand or shell because of the greater amount of available organic food. The highest numbers of benthic macroinvertebrates were collected in August 1969, with an average for all sites of 3,754 per m2. Intermediate numbers were recorded in January 1969 (961 per m2) and January 1970 (1795 per m2), and the lowest average number was recorded in May 1969 (664 per m2). Oligochaetes and chironomid, Coelotanypus sp. were the most widely distributed benethic macroinvertebrates collected (table 12). The other chironomids collected in the lake and Chaoborus sp. are potential nuisance species. Their numbers, however, were far below nuisance levels. CHEMICAL, PHYSICAL AND BIOLOGICAL CHARACTERISTICS OF WATER AND SEDIMENT, 1970-72 CHEMICAL AND PHYSICAL CHARACTERISTICS OF WATER PHYSICAL CHARACTERISTICS AND DISSOLVED SOLIDS The average specific conductance of the water samples from Lake Okeechobee for the seven monitoring transects ranged from 451 micromhos in October 1970 to 633 micromhos in May 1972. The average calculated dissolved solids ranged from 256 mg/l in October 1970 to 365 mg/l in May 1972. The dissolved solids and major dissolved constituents can easily be related to specific conductance. The increase in specific conductance, dissolved solids, and major constituents during the monitoring period was caused by back pumping of highly mineralized water into the lake, flow into the lake from drainage canals during the drought of 1971, and concentration of water in the lake caused by high evaporation rates. The lake stage averaged only about 13 feet for the time span October 1970 May 1972 as compared to an average of 15 feet for January 1969 to July 1970. The average dissolved solids during the later period, was 312 mg/1, and for the earlier period, 260 mg/l. REPORT OF INVESTIGATIONS NO. 71 Average dissolved oxygen concentrations in the lake for each transect ranged from 6.7 nig/I (84 percent of saturation) to 9.4 mg/1 (107 percent of saturation). A low dissolved oxygen concentration of 3.5 mg/1 (41 percent of saturation) occurred in Taylor Creek in November 1971. Because the lake stage was 2 feet lower October 1970 May 1972 than January 1969 July 1970, the lake was generally more turbid during the later period. The average measurements for the seven lake transects ranged from 9 to 48 JTU. The Kissimmee River and Taylor Creek were usually less turbid than the lake (table 17). The color of the lake water was generally less than 50 units but tended to increase beginning about in November 1971 because of pumpage and inflow of highly colored water from tributaries and drainage canals. In November, 1971 the color was 240 units at point 12 near the St. Lucie Canal and 100 units at point 5 in western part of the lake. These high colors were probably caused by inflow of highly colored water from the St. Lucie Canal (reverse flow), Fisheating Creek, Indian Prairie and Harney Pond Canals. The color of the water was not as high, only 80 units, at point 15 in the middle of the lake in May 1972. Most field and laboratory pH measurements in the lake were greater than 8.0. The pH of lake water was lowest in November 1971, after a period of heavy inflow of water of lower pH from tributaries and drainage canals. The lowest pH was 5.7 for the Kissimmee River and the next lowest was 6.0 for Taylor Creek, both in November, 1971. NITROGEN AND PHOSPHORUS The average total nitrogen (N) concentrations in Lake Okeechobee on the basis of data collected from transects 7 through 13 ranged from 0.66 to 3.0 mg/l. Most of the nitrogen was in the organic form, ranging from 81 to 96 percent of the total, and averaging 91 percent. Average inorganic nitrogen concentrations ranged from 0.06 to 0.40 mg/1. The average total nitrogen concentration for.all 7 transects were higher (1.6 mg/1) than for transects 1 6 (1.4 mg/1). The average inorganic nitrogen, however, was lower (0.14 mg/1) than for transects 1 6 (0.30 mg/1). On the basis of samples of river water collected 1970 72, the average total nitrogen concentration of the Kissimmee River was 1.1 mg/1 as compared to 0.99 mg/1 for those collected 1969 70. For Taylor Creek, the values are 1.9 and 1.6 mg/l. As during the project study, the ammonia nitrogen continued high in Taylor Creek, as much as 0.50 mg/l. For the last sampling in May 1972, however, the concentration was 0.04 mg/1. BUREAU OF GEOLOGY The average total phosphorus (P) concentrations in the lake for the seven transects (numbers 7 13) ranged from 0.03 mg/1 in May 1972 transectt 13) to 0.06 mg/1 in November 1971 transectt 11). The average total phosphorus for lake transects 7 13 was 0.05 mg/l as compared to 0.04 mg/1 for transects 1 6. The average total phosphorus concentrations for the Kissimmee River and Taylor Creek were lower after October 1970 than before. The average for the Kissimmee River for the monitoring period was 0.07 mg/l and before October 1970 was 0.08 mg/1. Similarly for Taylor Creek the values are 0.54 mg/1 after and 0.62 mg/l before. TRACE ELEMENTS The quantities of dissolved trace elements were very low in samples collected from site 15 in the center of Lake Okeechobee in November 1971 and May 1972 (table 17) (See also table on p. 5). Of the trace elements listed in table 17, five (aluminum, copper, iron, manganese, and zinc) have been cited by various investigators as essential for algal growth. For healthy algal growth, trace quantities of aluminum and 5 micrograms per liter of manganese are essential. In neither of the two samples analyzed was aluminum or manganese detected. CHEMICAL CHARACTERISTICS OF BOTTOM SEDIMENTS The analyses of the bottom sediment samples that were collected from transects 11 and 13 indicate that the sediments at sites 9 and 15 contain the highest percentage of organic material 16.87 and 15.57 percent of carbon, respectively, and sites 5 and 8 the least, 0.08 and 0.12 percent. This was as expected as the bottom material at sites 5 and 8 is mostly sand. As shown in table 17 the nitrogen, phosphorus, and iron were lowest at points 5 and 8. The bottom material at point 2 was marly, which accounted for the relatively small quantity of carbon, nitrogen, and iron present. BIOLOGICAL CHARACTERISTICS PHYTOPLANKTON Table 17 lists phytoplankton concentrations at each sampling point for transects 7-13. Table 18 lists the species of phytoplankton observed and average total concentrations in cells per millimeter for all sampling points during four transects from August 1971 to May 1972. The average lake concentrations during the last four transects were 11,100 cells/ml; 38,400/cells/ml; 8,400 cells/ml; and 24,700 cells/ml. REPORT OF INVESTIGATIONS NO. 71 Concentrations of phytoplankton into 1972 continued highest in the western and northern parts of the lake. Average concentration of phytoplankton decreased from 149,630 cells/ml in January 1971 to 38,400 cells/ml in November 1971. The concentrations of phytoplankton in the Kissimmee River and Taylor Creek, especially the Kissimmee, were surprisingly low. Not a single algal cell was observed in the Kissimmee River in August 1971 and only one species (Microcystis aeruginosa) with a concentration of 200 cells/ml, was observed in November 1971. A maximum concentration of 2,450 cells/ml was observed in the Kissimmee River in February 1972 during a no-flow period. The maximum concentration observed in Taylor Creek was 4,800 cells/ml in May, 1972 of which Aphenizonmenon holsaticum constituted 90 percent. Aphanizomenon holsaticum continued to be the dominant alga in the lake. It was dominant at all sites in November transectt 11), and May transectt 13), sites 8, 9, 12, and 15 in August transectt 10), and sites 5, 8, 9, and 15 in February transectt 12). In August Spirulina sp. was the dominant'alga at sites 2 and Merismopedia elegans was dominant at site 5. A total concentration of only 150 cells/ml was. observed at site 2 in February; 50 cells/ml each for Spirulina sp., Stephanodiscus niagarae and Synedr sp. In February the total concentrations at sites 12 consisted of 200 cells/ml Spirulina sp and 50 cells/ml Stephanodiscus niagarae. BENTHIC ORGANISMS The number of benthic organisms collected ranged from 129/m2 (square meter) at sites 2 in November 1971 to 12,837 m2 at site 12 in May 1972 (table 19). The average counts for all six sites was 1,376/m2 in November and 3,318 m2 in May 1972. In general, the number of organisms was highest at site 15 in the center of the lake and at site 12 near the St. Lucie Canal. The counts at site 12 were high, probably because the mucky bottom is rich in organic material and nutrients. The counts at site 2 were low, probably because the marly bottom is low in organic material and nutrients. At sites 5 and 8 the lake bottom is sandy. EUTROPHIC ASSESSMENT Eutrophication is part of the aging process of lakes from one life stage to another, ending in extinction. In the youngest stage of the life cycle, a lake is called oligotrophic and is characterized by low biologic productivity, low amounts of nutrients, and little sediment. Because a lake serves as a trap for BUREAU OF GEOLOGY nutrients originating in the surrounding drainage basin and entering through streams, with rainfall, and with ground-water inflow, in time the oligotrophic lake becomes mesotrophic, or partly enriched with nutrients. As aging continues, the shore encroaches upon the water, the nutrient content increases, plants grow abundantly, and silt and organic matter accumulate on the bottom. The lake then becomes eutrophic, or enriched, and is characterized by high biologic productivity, high nutrient content, and extensive sedimentation. The final stage before extinction is a pond, marsh, or swamp. The lake may eventually become dry land. Eutrophication may be accelerated by the cultural activities of man, such as altering of drainage basins, agricultural practices, deforestation, mine development, and urbanization. The chemical, physical, and biological data indicate that, in general, adequate nutrients were available for algal growth in Lake Okeechobee during 1969 72. With respect to the nutrients nitrogen and phosphorus, the average nitrate (N03-N) concentration for each transect ranged from 0.02 to 0.38 mg/1, and the average organic nitrogen (N) from 0.60 to 2.8 mg/l; organic nitrogen accounted for approximately 86 percent of the total nitrogen in the lake. The average orthophosphate (P04-P) and total phosphorus (P) concentrations for all transects were 0.03 and 0.04 mg/l, respectively. These values are comparable to those found during an investigation in 1969- 70 (Goolsby and McPherson, 1970) of the chemical and biological characteristics of the upper St. Johns River basin immediately north-northeast of Lake Okeechobee and its drainage system. Results of the latter study indicated that organic nitrogen averaged 1.0 mg/l and accounted for more than 90 percent of the total nitrogen and that total phosphorus (P) averaged 0.05 mg/1 on the main stem. The filtering action of marshes may remove large quantities of nutrients. The nutrient concentrations were very low in samples collected from Lake Okeechobee at sites 17 and 18 in areas of dense emergent marsh vegetation in August 1969. Also, no phytoplankters were observed at site 18; only four filaments of Oscillatoria cortina were observed at site 17. The greater than normal inflow from tributaries and rainfall from late 1969 to March 1970 contributed increased loads of nutrients, which, in turn, triggered increased concentration of phytoplankton to bloom levels and a change in dominant species from green (Pediastrum simplex) to blue-green algae (Aphanizomenon holsaticum) These changes began in the northern part of the lake. The dynamic shifts in phytoplankton population reflect a change in the environmental conditions, at least temporarily, within the lake. Goolsby and McPherson (1970) report increased concentration of phytoplankton to bloom levels (approximately 75,000 cells/ml), consisting of REPORT OF INVESTIGATIONS NO. 71 57 the blue-green algae, Anabaena Circinalis associated with eutrophic lakes, in Blue Cypress Lake in July 1970. There was no evidence of bloom conditions, however, in 1971 72.'Blue Cypress Lake is affected by man less than Lake Okeechobee. Increases in concentrations of nutrients, such as silica, nitrate, phosphate, iron, and organic material (as approximated by color determinations) were relatively large in the northern part of Lake Okeechobee in January 1970 (table 13) after the period of heavy runoff. Available data indicate decreased concentrations of these nutrients during the subsequent phytoplankton bloom in July 1970. Phytoplankton concentration in Lake Okeechobee had significantly decreased by April 1971. Examples of changes in selected nutrient concentrations associated with the high nutrient flux into the lake in January and April 1970 and the subsequent algal bloom in July 1970 follow: Site No. and Nutrient Aug. 1969 (Prior inflow) Jan. 1970 Apr. 1970 (During and Following inflow) July 1970 (During algal bloom) 5-Silica mg/l Nitrate (NO 3-N) mg/l Orthophosphate (P04-P) mg/1 Color Units 6-Silica mg/1 Nitrate (N03-N) mg/l Orthophosphate (P04-P) mg/1 Color Units 7-Nitrate (NO3-N) mg/1 Orthophosphate (P04-P) mg/1 Color Units Iron mg/l 8-Silica mg/1 Nitrate (NO3-N) mg/1 Orthophosphate (P04-P) mg/l Color units Iron. mg/1 9-Orthophosphate (P04-P) mg/1 Color Units Iron mg/1 6.6 .07 .010 15 5.8 .02 .007 15 0.02 .016 30 .04 6.1 0.02 .020 20 .02 0.013 15 L 6.2 .3 1.1 .049 .016 60 .3 .052 -- 0.09 .098 60 .12 3.1 0.05 .14 120 .16 5.9 0.2 .029 60 0.11 0.029 100 60 .12 - 2.8 .0 .007 25 1.1 0.0 0.013 10 BUREAU OF GEOLOGY Lake Okeechobee is effectively mixed, and dissolved oxygen and temperature are not stratified. Dissolved-oxygen values are high, whereas the low values of ammonia and nitrite indicate the absence of organic pollution. The average numbers of benthic organisms were well below levels normally considered indicative of highly eutrophic waters. Although the warm water (as much as 340C) and adequate nutrient concentrations are conducive to high biologic productivity, algal growth may be inhibited by the high turbidity of the lake. The data collected and evaluated suggest that Lake Okeechobee is in an early eutrophic condition. The investigation coincided with a period of greater than normal rainfall and runoff, resulting in a relatively high nutrient flux into the lake. The data document extensive physical, chemical, and biological variability within the lake system over a short-time span and cannot be utilized for predicting long-term trends. No reliable comprehensive nutrient or biological data are available for historical comparisons; however, phosphorus concentration was relatively high near the mouth of Taylor Creek in 1952 (Odum, 1953), similar to the concentration during the present investigation. Regional comparisons, although sparse, suggest that water quality of Lake Okeechobee, as of 1969 70, was not significantly different that that of other water bodies in southern peninsular Florida. REPORT OF INVESTIGATIONS NO. 71 SELECTED REFERENCES Ager, Lothian 1970 Annual report, Lake Okeechobee project: Florida Game and Fresh Water Fish Commission (unpublished). Brenzonik, P. L., Morgan, W. H., Shannon, E. E., and Putnam, H. D. 1969 Eutrophication factors in north central Florida lakes: Florida Univ. Eng. and Indus. Expt. Sta. Buddhari, W. 1960 Cobalt as an essential element for blue-green algae: Unpublished PhD dissertation, Univ. of California, 163 p. Clayton, B. S., Neller, J. R., and Allison, R.V. 1942 Water control in the peat and muck soils of the Florida Everglades: Florida Agr. Expt. Sta., Bull. 378. Cobb, H. D., and Meyers, J. 1964 Comparative studies of nitrogen fixation and photosynthesis in Anabaena cylindrica: Am. Jour. Botany, 51:753-762. Cooke, C. W. 1939 Scenery of Florida: Florida Geol. Survey Bull. No. 17, 118 p. Davis, J. H., Jr. 1943 The natural features of southern Florida: Florida Geol. Survey Bull. no. 25, 311 p. Davis, J. H., Jr. 1946 The peat deposits of Florida: Florida Geol. Survey Bull. no. 30, 247 p. Duchrow, Richard M; 1970 Annual, progress report for investigation project as required by Federal Aid in Fish Restoration, Dingell-Johnson Project F-21-4, 1969- 70: Florida Game and Fresh Water Fish Commission. Eyster, C. 1964 Micronutrient requirements for green plants, especially algae: in Algae and Man D. F. Jackson (ed.), p. 86 119. Frey, D. G. (Ed.) 1966 Limnology in North America: Univ. of Wise. Press, Madison, 734 p. BUREAU OF GEOLOGY Gambell, A. W., and Fisher, D. W. 1966 Chemical composition of rainfall, eastern North Carolina and southeastern Virginia: U. S. GeoL Survey Water Supply Paper 1535-K. Gerloff, G. C., and F. Skoggs 1957 Availability of iron and manganese in southern Wisconsin lakes for the growth ofMlicrocystis aeruginosa: Ecology 38 (4): 551-556. Goolsby, D. A. and McPherson, B. F. 1970 Preliminary evaluation of chemical and biological characteristics of the upper St. Johns River Basin, Florida: U. S. Geol. Survey open-file report. Greeson, Philip E. 1971 Limnology of Oneida Lake with emphasis on factors contributing to algal blooms: New York State Dept. Environmental Conserv., open-file report. Heilprin, Angelo 1887 Explorations on the west coast of Florida and in the Okeechobee Wilderness: Wagner Free Inst. Sci. Higer, Aaron L-, and Kolipinski, Milton C. 1970 Sources of pesticides in Florida waters: U. S. Geol. Survey open-file report. Holcomb, Dennis E. 1968 Annual progress report for research project as required by Federal Aid and Fish Restoration, Dingell-Johnson Project F-21-R-2: Florida Game and Fresh Water Fish Commission, 1967 68. Hutchinson, G. Evelyn 1957 A treatise of limnology, v. 1, geography, physics, and chemistry: John Wiley and Sons, N. Y., 1015 p. Joyner, Boyd F., and Greeson, Phillip E. 1971 Appraisal of biological condition and nutrient content of Lake Okeechobee, Florida: Presented at International Sumposium on Manmade Lakes, Knoxville, Tenn., May 3 7, 1971. Loveless, C. M. 1959 A study of the vegetation in the Florida .Everglades: Ecology 40: 1 -9. Meyer, B. S., Anderson, D. B., and Bohning, R. H. 1964 Introduction to plant physiology: D. Van Nostrand Co., Princeton, N. J., 541 P- REPORT OF INVESTIGATIONS NO. 71 Meyer, F. W. 1971 Seepage beneath Hoover Dike, southern shore of Lake Okeechobee, Florida: Florida Dept. Nat. Resources, Bur. Geol., Rept. Inv. 58 (in press). Odum, Howard T. 1953 Dissolved phosphorus in Florida Waters: Florida Geol. Survey, Rept. Inv. 9. Parker, G. G., Ferguson, G. E., and Love, S. K., and others 1955 Water resources of southeastern Florida, with special reference to the geology and ground water of the Miami area: U. S. Geol Survey Water Supply Paper 1255. Provasoli, L. 1958 Nutrition and ecology of protozoa and algae: Ann. Rev. Micro Biol., 12:279-303. Provasoli, L., and Pinter, J. J. 1953 Ecological implications of in vitro nutritional requirements of algal flagellates: New York Acad. Sci Annuals, 56:839-851. Rainwater, F. H., and Thatcher, L. L. 1960 Methods for collection and analysis of water samples: U. S. Geol. Survey Water Supply Paper 1454. Reid, G. K. 1961 Ecology of inland waters and estuaries: New York, Rheinhold PubL Co., 375 Ryther, J. H., and Kramer, D. D. 1961 Schelske, C. 1962 Relative iron requirements of some coastal and offshore plankton algae: Ecology 42 (2): 444-446. L. Iron. organic matter, and other factors limiting primary productivity in a marl lake: Science 136 (3510):45-46. Schneider, R. F., and Little, J. A. 1969 Characterization of bottom sediments and selected nitrogen and phosphorus sources in Lake Apopka, Florida: Athens, Georgia, Federal Water Pollution Control Admin. Shannon, J. E. 1965 Nutrient requirements for aquatic plants, Part 1: Water Chemistry Seminar, Wisconsin Univ. 62 BUREAU OF GEOLOGY Smith, D. B. 1965 A study of the hydrologic characteristics of the Caloosahatchee River basin: Cent. Dist. Misc. PubL. Visher, F. N., and Hughes, G. H. 1969 The difference between rinfall and potential evaporation in Florida: Florida Dept. Nat. Resources, Bur. GeoL, Map Ser. 32. Waker, J. B. 1953 Inorganic micronutrient requirements of Chlorella 1. Requirements for calcium (or strontium), copper and molybdenum: Arch. Biochem. 46:1-11. REPORT OF INVESTIGATIONS NO. 71 APPENDIX Table 13 Chemical Analyses of Water in Lake Okeechobee (Results in milligrams per liter except as noted) Analysis made by U. S. Geological Survey Blcabonate Carbonate (HcV3) (C03) S1969 /1 Jan-16 0925 15.3 13 0 15 4.6 0.03 47 13 40 3.0 152 45 62 0.3 0.3 0.003 0.03 1 Jan-16 0925 15.3 13 0 15 5.1 .07 47 13 39 2.7 160 152 46 60 .3 .3 .009 0.01 1 Jan-16 0926 15.3 13 3 15 - 1 Jan-16 0927 15.3 13 6 15 5.5 .07 47 13 39 2.8 168 148 44 66 .3 .3 .009 .00 1 Jan-16 0928 15.3 13 9 15 -- - 1 Jan-16 0929 15.3 13 12 15 4.7 .08 47 13 39 2.7 172 152 44 62 .2 .3 .006 .01 JJi May-15 0930 14.2 11.5 0 25 6.2 .02 50 14 43 2.9 164 42 65 .4 .2 .003' .04 1 May-15 0930 14.2 11.5 0 25 8.1 .02 50 14 43 2.9 162 49 63 .3 .2 .003 .02 .1 May-15 0931 14.2 11.5 6 24 6.2 .03 50 14 43 2.9 162 47 64 .3 .3 .006 .01 1 May-15 0932 14.2 11.5 11.5 24 6.2 .02 49 15 43 2.9 162 48 63 .4 .2 .006 .05 1 Aug-27 1545 14.4 10 0 30 6.2 .02 38 13 42 3.0 122 12 45 63 .3 .02 .000 .04 1 Aug-27 1545 14.4 10 0 30 6.3 .03 39 13 43 2.9 104 136 18 44 66 .3 .00 ..000 .05 1 Au27 1546 14.4 10 5 30 5.9 .02 40 13 42 3.5 102 136 18 42 64 .3 .1 .009 .05 1 Au'27 1547 14.4 10 10 30 6.6 .07 41 13 42 2.9 108 136 16 44 64 .3 .05 .000 .04 1970 1/I Jan-15 1430 15.9 12.5 0 12.5 9.2 .02 42 11 34 2.4 132 34 53 .3 .3 .000 .06 1 Jan-15 1430 15.9 12.5 0 12.5 10 .00 43 12 34 2.6 146 132 4 41 53 .4 .2 .000 .05 1 Jan-15 1431 15.9 12.5 6 12.5 140 6 - 1 Jan-15 1431 15.9 12.5 7.5 12.5 9.5 .03 43 11 33 2.6 134 34 52 .3 .2 .006 .00 1 Jan-15 1432 15.9 12.5 12 12.5 9.5 .00 42 11 33 2.6 142 132 6 40 53 .4 .2 .006 .01 1969 2 Jan-16 1015 15.3 13 0 15.5 5.1 .08 47 13 39 2.7 160 152 45 62 .3 .3 .009 .00 2 May-15 1005 14.2 13 0 25 6.4 .02 52 15 44 3.0 170 51 64 .4 .09 .006 .01 2 Aug-28 1000 14.4 0 29 7.2 .03 44 13 43 3.0 126 152 14 41 64 .3 .02 .000 .05 1970 2 Jan-14 1600 15.9 14.5 0 12 10 .11 44 12 37 2.7 168 138 0 44 55 .4 .2 .009 .00 2 Apr-21 1230 15.6 34 9.1 40 10 30 2.4 122 28 45 .3 .2 .009 .07 2 Jul-16 1015 14.2 29.5 1.8 41 10 29 2.4 132 35 45 .4 .05 .003 .04 i 0 CI z p,, Table 13 Chemical Analyses of Water in Lake Okeechobee (Results in milligrams per liter except as noted) Analysis made by U. S, Geological Survey Dissolved Haudneuss pH value Chlorohyll Diu ed a C3 SSolid Ca CO3 ug/ Oxygen 1969 /1 Jan-16 0 0.89 1.2 0.000 0.006 291 318 171 46 520 7.6 35 - 1 Jan-16 0 .83 1.2 .0;0 .026 290 316 152 171 46 520 510 8,2 7.4 40 0.70 19 27 67 113 9.7 95 1 Jan-16 3 9.5 93 1 Jan-16 6 .83 1.2 .016 .026 292 341 171 50 520 520 8.2 7.4 35 9.5 93 1 Jan-16 9 9.5 93 1 Jan-16 12 .93 1.3 .013 .020 289 318 171 46 520 510 8.0 7.4 40 9.5 93 1 May-1S 0 .99 1.2 .003 .006 305 341 183 48 556 8.1 20 -- - I May-15 0 .96 1.1 .010 .016 311 348 80 183 50 540 556 7.9 20 14 1.50 7 5 16 28 8.0 95 1 May-15 6 .87 1.2 .010 .016 309 347 183 50 540 556 7.9 20 16 7.2 85 1 My-15 11.5 1.2 1.4 .010 .013 308 354 184 51 545 556 7.9 20 16 10.3 121 J1/ Aug-27 0 .94 1.0 .006 .013 283 329 149 49 490 8.8 20 - 1 Aug-27 0 1.5 1.6 .036 .042 282 354 54 151 40 438 510 8.9 7.5 10 15 1.75 55 37 23 115 7.7 101 1 Aug-27 5 1.3 1.5 .020 .023 279 306 154 42 498 520 8.9 7.5 10 22 7.2 95 1 Aug-27 10 1.6 1.7 .016 .026 281 318 156 45 491 525 8.9 7.6 10 13 5.7 75 1970 1 Jan-15 0 1.4 .8 .016 .029 252 289 150 42 453 8.1 30 - 1 Jan-15 0 2.6 .9 .052 .068 262 290 169 157 49 410 468 8.4 8.0 60 29 .50 10 0 1.5 12 10 93 1 Jan-15 6 410 8.4 -- 9.8 92 1 Jan-IS 7.5 1.3 1.5 .055 .068 253 285 153 43 450 8.0 60 31 - 1 Jan-15 12 1.0 1.3 .050 .062 258 289 150 42 408 456 8.4 8.1 60 29 8.0 75 1969 2 Jan-16 0 .87 1.2 .020 .026 291 321 171 46 525 510 8.0 7.5 35 8 6 11 25 9.9 98 2 May-15 0 1.0 1.1 .010 .010 320 351 141 191 52 565 570 7.9 20 32 5 5 7 17 7.7 93 2 Au 28 0 1.9 2.0 .026 .029 291 339 56 164 39 452 540 8.8 7.8 10 18 71 54 0 125 6.8 87 2 Jan-14 0 1.4 1.7 .050 .065 274 305 237 160 47 488 486 8.2 7.8 60 32 8 0 4 12 9.8 91 2 Apr-21 1.2 .055 .062 226 266 141 41 410 408 8.5 8.1 60 - 2 Jul-16 .62 .033 .033 230 265 144 36 415 410 8.7 8.1 20 25 7.2 94 Table 13 Chemical Analyses of Water in Lake Okeechobee Continued (Results in milligrams per liter except as noted) Analysis made by U. S. Geological Survey Bicarbonate Carbonate SM (HC03) (Co3) 1969 3 Jan-16 1350 15.3 11.5 0 16 6.1 0.09 47 14 41 2.8 172 152 47 63 0.3 0.4 0.009 0.01 3 May-15 1030 14.2 10 0 26 .6.0 .02 51 15 44 2.9 162 50 66 .3 .09 .003 .02 3 Au.28 1100 14.4 12 0 29 7.0 .03 42 13 43 3.1 116 140 14 42 64 .3 .02 .000 .07 1970 3 Jan-15 1530 15.9 15.5 0 13 8.8 .05 43 12 35 2.5 138 134 38 53 .3 .2 .006 .08 1969 4 Jan-16 1430 15.3 12 0 16 5.0 .06 48 13 41 2.8 168 154 48 63 .4 .4 .006 .02 4 May-15 1100 14.2 10 0 27 6.1 .01 50 14 43 2.7 160 48 65 .4 .09 .003 .03 4 Au-28 1130 14.4 12 0 29 6.5 .04 43 13 42 2.2 112 144 16 42 62 .2 .05 .000 .05 1970 4 Jan-15 1600 15.9 12.5 0 13.5 9.4 .06 43 12 35 2.5 143 138 5. 39 53 .3 .2 .006 .01 1969 S Jan-14 1100 15.3 10 0 14 4.1 .07 46 13 38 2.6 156 148 45 60 .4 .3 .006 .02 5 May-13 1130 14.2 0 26 .8 .00 51 14 44 2.7 172 162 50 66 .4 .02 .006 .01 5 Au-27 0920 14.4 10 0 29 6.6 .02 40 14 44 3.0 118 140 12 45 66 .3 .07 .006 .04 5 Jan-13 1210 15.9 11.5 0 11 11 .02 45 12 37 2.6 164 142 0 42 57 .3 .3 .006 .02 5 Apr-21 1450 15.6 30 6.2 56 16 41 3.2 174 56 60 .5 1.1 .006 .11 Jul.16 1115 14.2 31 2.8 44 13 34 2.6 148 45 55 .5 .00 .003 .04 1969 6 Jan-14 1145 15.3 12 0 14.5 4.2 .05 47 13 40 2.7 160 152 46 62 .3 .2 .006 .02 6 Jan-14 1146 15.3 12 3 14 160 -- - 6 Jan-14 1147 15.3 12 6 14.3 3.7 .09 48 13 40 2.7 160 154 46 63 .2 .2 .003 .02 6 Jan-14 1148 15.3 12 9 14 - 6 Jan-14 1149 15.3 12 12 14 3.7 .04 48 13 40 2.7 160 152 42 62 .3 .3 .006 .01 1/6 May-13 1030 14.2 9 0 25 5.1 .03 42 11 32 2.4 138 37 48 .3 .0 .003 .02 6 May-13 1030 14.2 9 0 25 4.8 .03 43 10 31 2.2 146 136 38 50 .4 .00 .006 .09 6 May-13 1030 14.2 9 4.5 25 152 - 6 May-13 1030 14.2 9 5 25 4.9 .03 44 10 32 2.2 136 38 51 .4 .05 .003 .07 6 May-13 1032 14.2 9 9 25 5.0 .07 44 10 32 2.2 152 138 38 50 .4 .02 .003 .05 /6 Aug-27 0830 14.4 11 0 29 6.8 .02 42 13 41 2.8 142 43 64 .3 .02 .006 .02 6 Aug-27 0830 14.4 11 0 29 5.8 .03 42 13 43 2.9 120 144 12 42 63 .02 .000 .03 6 Aug-27 0831 14.4 11 5 29 5.6 .02 41 13 43 2.9 124 140 12 44 67 .3 02 .006 .02 6 Aug-27 0832 14.4 11 11 29 5.6 .02 42 13 42 2.9 124 144 12 40 64 .3 .02 .000 .15 0 0 N H 0 z z 9 14 Table 13 Chemical Analyses of Water In Lake Okeechobee Continued (Results in milligrams per liter except as noted) Analysis made by U. S. Geological Survey Di olved Hudnmu Co H valu Chlo ohyl Di olved Sg So lids C C03 p v p u uS/iY Oxygen S ) t a b j 1969 3 Jan.16 0 .84 1.3 0.020 0.026 298 334 125 50 542 530 7.9 7.5 40 11 11 9 31 8.6 86 3 May-15 0 1.2 1.3 .010 .016 316 351 118 189 56 555 560 8,0 20 16 7 6 11 24 8,2 100 3 Au-28 0 1,9 2.0 .020 .029 283 346 368 159 44 448 530 8.8 7.7 20 17 75 21 72 168 7,4 95 3 Jan-15 0 1.2 1.5 .042 .059 260 300 232 157 47 408 452 8.4 7.9 60 26 7.5 0 3 10 10.2 96 1969 4 Jan-16 0 .91 1.3 .013 .020 299 328 174 48 538 530 7.9 7.4 35 4 12 9 25 8.9 89 4 May-15 0 1.3 1.4 .003 .013 309 349 116 183 52 545 550 8.1 25 16 12 4 20 36 8.0 99 4 Aug.28 0 1.4 1.5 .010 .016 279 340 396 161 43 488 520 8.9 7.7 20 17 132 260 370 762 8.2 105 1970 4 Jan-15 0 1.4 1.7 .039 .062 263 309 214 157 44 475 468 8.4 7.9 50 31 10 0 1.5 12 9.5 90 1969 5 Jan-14 0 .85 1.2 .010 .010 283 312 164 43 520 500 6.8 7.4 35 12 13 16 41 10.1 97 5 May-13 0 1.1 1.1 .003 .006 314 351 162 185 52 545 560 8.2 7.8 30 18 12 7 18 37 7.6 93 5 Aug-27 0 1.1 1.2 .010 .013 288 327 565 158 43 490 540 8.7 8.0 15 11 18 22 84 124 8.1 104 1970 5 Jan-13 0 1.6 1.9 .050 .068 278 322 123 162 46 491 481 8.1 7.8 50 32 9 1.5 7.5 18 9.5 85 S Apr-21 0 1.5 .016 .036 330 372 206 63 580 570 8.9 8.2 60 - 5 Jul-16 0 1.0 .026 .010 270 333 164 42 478 480 9.0 8.1 25 18 7.7 103 1969 6 Jan-14 0 .88 1.1 .016 .026 291 319 173 171 46 555 510 8.3 7.4 35 .92 10 9 11 30 10.0 97 6 Jan-14 3 -- -- -- -- 8.3 -- 10.2 98 6 Jan-14 6 .81 1.1 .013 .023 294 321 174 48 555 520 8.0 7.5 40 10.0 97 6 Jan-14 9 10.2 98 6 Jan-14 12 .81 1.1 .016 .026 288 318 174 49 555 510 8.1 7.5 40 10.1 97 1/6 May-13 0 .73 .75 .000 .006 246 272 150 37 442 8.0 20 - 6 May-13 0 1.7 1.8 .006 .013 246 281 223 149 37 430 439 8.2 7.5 40 35 .75 22 8 18 48 7.5 89 6 May-13 4.5 430 8.2 -- 7.5 89 6 May-13 5 1.6 1.7 .006 .016 250 284 151 40 441 7.6 50 35 - 6 May-3 9 2.0 2.1 .006 .039 250 291 151 38 435 448 8.2 7.4 50 35 - 1/6 Aug-27 0 0.95 1.0 .006 .013 283 324 159 42 520 8.2 5 - 6 Aug-27 0 1.1 1.2 .006 .013 283 340 304 159 41 498 515 8.7 7.9 15 7 33 36 87 156 7.7 99 6 Aug-27 5 1.1 1.2 .010 .016 286 324 156 42 442 515 8.7 8.0 30 7 2.83 7.4 95 6 Aug.27 11 1.1 1.1 .016 .023 281 328 159 41 498 510 8.7 7.9 20 8 9.8 126 Table 13 Chemical Analyses of Water in Lake Okeechobee Continued (Results in milligrams per liter except as noted) Analysis made by U. S. Geological Survey Bicarbonate Carbonate SC (HCO3) (C03) 1970 J/6 Jan-13 1100 15.9 13.5 0 9.5 0.02 42 11 34 2.6 130 40 53 0.3 0.2 0.000 0.02 6 Jan-13 1100 15.9 13.5 0 10.5 10 .00 42 11 34 2.6 146 132 8 40 52 .4 .3 .006 .01 6 Jan-13 1101 15.9 13.5 6 11 10 .03 43 11 34 2.6 142 130 6 40 52 .3 .3 .009 .00 6 Jan-13 1102 15.9 13.5 13.5 10 11 .00 43 11 34 2.6 156 134 4 39 54 .3 .2 .006 .02 1969 j/7 Jan-14 1300 15.3 12 0 14 4.6 .02 48 13 42 2.8 156 42 66 .3 .4 .003 .07 7 Jan-14 1300 15.3 12 0 14 162 - 7 May-13 0900 14.2 11 0 25 5.5 .02 49 13 38 2.6 170 156 -- 45 61 .5 .02 .003 .10 7 Aug-27 0800 14.4 10 0 29 5.2 .04 38 12 38 2.6 104 124 10 38 58 .2 .02 .000 .15 1970 7 Jan-13 1030 15.9 13 0 11 6.0 .12 32 6.7 20 1.9 88 95 2 24 32 .3 .09 .009 .00 1969 ./8 Jan-13 1715 15.3 12 0 15 5.3 .02 51 15 45 3.0 164 50 69 .3 .5 .000 .01 8 Jan-13 1715 15.3 12 0 15 - 8 May-12 1500 14.2 11 0 27 5.7 .02 48 12 40 2.6 176 154 45 60 .4 .00 .003 .00 8 Auf-25 1340 14.4 12 0 30 6.1 .02 39 12 39 2.7 114 136 12 42 59 .3 .02 .000 .06 1970 8 Jan-12 1340 15.9 13 0 14 3.1 .16 29 3.3 11 1.6 76 65 0 14 19 .3 .05 .006 .09 8 Apr-21 0930 15.6 5.9 37 9.4 27 2.2 114 32 41 .3 .2 .006 .09 8 Jul-16 0810 14.2 29 1.1 41 10 29 2.4 136 35 46 .4 .00 .000 .04 1969 ./9 Jan-13 1600 15.3 12 0 15 6.2 .02 52 15 47 3.2 172 54 72 .4 ,5 .003 .02 9 Jan-13 1600 15.3 12 0 15 - 9 May-12 1415 14.2 11 0 26 6.1 .03 46 13 39 3.0 172 152 42 59 .4 .07 .003 .01 9 Aug-25 1500' 14.4 12.5 0 30 5.2 .03 41 12 40 2.7 122 148 8 42 60 .3 .02 .000 .06 1970 9 Jan-12 1500 15.9 13 0 14 3.6 .12 28 5.0 16 1.7 74 79 0 18 28 .2 .05 .006 .05 9 Apr-21 1530 15.6 32 5.1 35 8.7 25 2.1 112 18 38 .3 .09 .006 .11 10 Jan-14 1700 15.3 13.5 0 15 .6.7 .07 50 15 46 3.0 190 170 52 72 .3 .5 .009 .01 10 May-14 0840 14.2 12 0 25 7.0 .04 51 14 44 2.8 172 168 4 48 65 .5 .09 .006 .01 10 Au-26 '0800 14.4 13 0 28 6.3 .01 44 13 40 2.8 128 152 12 42 58 .3 .05 '.003 .01 10 Jan-13 1645 15.9 15 0 11.5 8.4 .02 37 9.0 26 2.2 124 112 0 32 41 .3 .02 .009 .00 Table 13 Chemical Analyses of Water in Lake Okeechobee. Continued (Results in milligrams per liter except as noted) Analysis made by U. S. Geological Survey D C CO3a W *j p. value Chlorophyll Dllved Sd CP Oxygen 1970 /6 Jan13 0 .7 .97 0.020 0.029 258 282 150 44 452 8.1 30 - 6 Jan.13 0 1.3 1.6 .052 .075 258 285 113 150 42 455 459 8.4 8.1 60 33 .50 10 0 1.5 12 11.2 100 6 Jan-13 6 1.7 2.0 .068 .085 258 287 153 46 400 458 8.4 7.8 60 32 11.1 100 6 Jan-13 ,13.5 1.6 1.9 .055 .068 262 292 153 43 402 451 8.3 7.8 60 34 11.0 97 1969 '/7 Jan-14 0 .87 1.4 .000 .006 298 332 174 46 ~- 530 7.5 40 - 7 Jan-14 0 76 585 8.2 7 6 5 18 10.1 97 7 May13 0 1.6 1.7 .003 .010 292 326 234 176 48 505 520 8.2 7.6 40 12 8 1 0 9 7.8 93 7 Au:27 0 .88 1.0 .016 .026 253 305 282 145 43 445 470 8.7 7.4 30 11 32 13 53 98 7.3 94 19 7 Jan-13 0 1.2 1.3 .098 .12 171 202 118 108 30 300 309 8.3 7.8 60 37 12 0 6 18 10.2 92 1969 j18 Jan-13 0 .89 1.4 .010 .020 322 353 188 54 560 7.6 40 - 8 Jan-13 0 165 545 -- 10 11 15 36 10.1 99 8 May-12 0 1.3 1.3 .006 .016 290 330 208 170 ,44 508 520 8.2 7.9 30 56 5.5 .5 3 9 - 8 Ag-2 0 1.1 1.2 .020 .029 267 322 393 147 36 482 500 8.8 7.9 20 10 0 0 0 0 7.7 101 1970 8 Jan-12 0 1.4 1.6 .14 .15 110 152 87 76 23 210 199 8.2 7.5 120 23 9 0 1.5 10 9.8 :94 8 Apr-21 0 1.1 ..029 .039 212 251 131 38 385 388 8.3 7.6 60 - 8 Jul-16 0 .89 .013 .016 232 265 144 32 408 420 8.2 8.1 10 19 7.5 96 1969 J/9, Janl13 0 1.1 1.6 .006 .013 337 368 191 50 580 7.6 35 - 9 Jan13 0 110 375 5 2 0 7 9.0 88 9' May-12 0 1.2 1.3 .016 .020 284 309 168 169 44 505 515 8.2 7.9 20 35 9 1 2 12 7.8 95 9 Aug 25 0 1.2 1.3 .013 .020 276 306 375 152 31 500 500 8,7 7.8 15 9 0 0 0 0 7.3 96 1970 9 Jan-12 0 1.0 1.1 .11 .13 140 179 82 91 26 238 250 8.2 7.6 100 21 9 3 3 15 10.5 101 9 Apr-21 0 .97 .029 .042 188 234 124 32 370 359 8.9 7.6 60 - 1969 10 Jan-14 0 .96 1.4 .020 .029 329 361 186 47 596 570 8.0 7.5 35 5 2 0 7 10 98 10 May-14 0 1.3 1.4 .016 .023 316 355 188 185 47 545 560 8.5 8.0 30 23 9 1 13 23 7.6 91 10 Aug-26 0 1.2 1,2 .023 .029 282 299 340 164 39 498 520 8.8 7.9 5 9 32 26 18 76 7.3 92 10 Jan13 0 1.6 1.8 .059 .091 212241 218 130 38 380 378 8.4 7.8 60 34 10 Jan-13 0 1.6 1.8 .059 .091 212 241 218 130 38 380 378 8.4 7.8 60 34 - .I/- Filtered Table 13 Chemical Analyses of Water in Lake Okeechobee Continued (Results in milligrams per liter except as noted) Analysis made by U. S. Geological Survey Bicarbon- Carbonate ate(HCO3) (C03) I 1969 11 Jan-14 1600 15.3 13 0 15 6.3 0.07 50 15 45 3.0 188 166 50 70 0.3 0.4 0.003 0.01 11 Jan-14 1601 15.3 13 3 15 - 11 Jan-14 1602 15.3 13 6 15 6.4 .07 50 15 44 3.0 188 168 50 68 .3 .5 .012 .01 11 Jan-14 1603 15.3 13 9 15 - 11 Jan-14 1604 15.3 13 12 14 6.8 .07 51 15 45 3.0 190 166 51 70 .3 .5 .012 .01 /11 May-14 0910 14.2 12 0 25 6.0 .01 48 12 39 2.6 152 43 60 .5 .07 .003 .00 11 May-14 0910 14.2 12 0 25 6.7 .05 48 12 39 2.5 164 152 4 45 59 .4 .07 .006 .02 11 May-14 0911 14.2 12 6 25 6.0 .07 48 12 38 2.6 166 152 45 59 .4 .07 .002 .01 11 May-14 0912 14.2 12 12 25 6.3 .07 48 12 38 2.6 166 150 42 59 .5 .09 .002 .00 11 Aug-26 0830 14.4 13 0 28 5.2 .03 44 12 37 2.7 138 8 38 55 .3 .00 .000 .05 11 Aug-26 0845 14.4 13 0 28 5.9 .03 43 12 37 2.8 118 144 14 41 54 .4 .02 .002 .02 11 Aug-26 0846 14.4 13 6 28 5.4 .03 42 11 37 2.7 120 144 14 37 56 .3 .02 .000 .01 11 Aug-26 0847 14.4 13 13 29 6.3 .03 43 12 37 2.7 124 144 12 40 54 .3 .05 .009 .03 1970 i/11 Jan-13 1545 15.9 15 0 11 9.4 .03 40 9.7 31 2.4 124 36 47 .3 .2 .000 .00 11 Jan-13 1545 15.9 15 0 11 10 .18 41 10 30 2.5 138 122 0 36 48 .3 .2 .009 .00 11 Jan-13 1546 15.9 15 7.5 9 9.9 .05 40 10 30 2.4 144 124 0 36 48 .3 .2 .009 .01 11 Jan-13 1547 15.9 15 15 9 9.6 .07 42 11 32 2.5 140 126 0 38 50 .3 .2 .009 .05 1969 J/12 Jan-14 1530 15.3 8 0 15.5 5.9 .02 51 15 47 3.2 170 52 70 .4 .00 .000 .14 12 Jan-14 1530 15.3 8 0 15.5 192 - 12 May-14 1005 14.2 7 0 25 5.3 .02 44 11 34 2.5 148 138 33 52 .4 .05 .006 .06 12 Aug-26. 0930 14.4 8 0 30 5.3 .02 42 11 36 2.7 128 140 6 37 54 .3 .07 .006 .03 1970 12 Jan-13 1515 15.9 10 0 12 7.8 .11 40 9.4 29 2.3 132 124 0 33 45 .3 .2 .006 .03 12 Apr-21 1045 15.6 27.5 5.2 33 7.2 21 2.0 94 20 31 .3 .1 .012 .16 12 Jul-16 0900 14.2 29 2.2 41 10 29 2.4 128 35 44 .4 .00 .003 .05 1969 13 Jan-16 1225 15.3 14 0 15.5 6.1 .07 50 15 45 3.0 180 168 50 68 .4 .2 .009 .01 13 May-14 1145 14.2 13,5 0 25 6.0 .03 46 12 36 2.5 148 146 40 55 .4 .07 .006 .04 13 Au -28 0945 14.4 14 0 29 5.6 .02 41 13 42 3.0 124 148 14 39 62 .3 .07 .000 .03 19 13 Jan-14 1515 15.9 16.5 0 13.5 11 .10 46 12 38 2.7 144 142 0 44 59 .3 .3 .006 .08 Table 13 Chemical Analyses of Water in Lake Okeechobee Continued (Results in milligrams per liter except as noted) Analysis made by U. S, Geological Survey SDissolved Hudneuu coS2i 6 Disolvod SSoUd Ca CO03 I,2 pH value ChlosophyU Oxygen 111 JM~ 111111 b a0 JJ jj 1969 11 Jan-14 0 .96 1.4 0.026 0.036 324 355 110 186 50 610 560 8.0 7.5 35 .50 5 3 4 12 10.0 98 11 Jan-14 3 --- -- 10.0 98 11 Jan-14 6 .95 1.4 .026 .036 322 353 186 49 620 560 8.0 7.4 35 10.0 98 11 Jan-14 9 -- 9.3 91 11 Jan-14 12 1.0 1.5 .26 .036 327 358 188 52 620 560 8.1 7.5 35 8.0 87 1/11 May-14 0 1.1 1,2 .000 .003 286 325 170 45 510 8.1 40 - 11 May-14 0 1.1 1,2 .013 .020 288 322 173 170 45 500. 520 .8.4 7.8 40 35 1.00 11 2 15 28 7.7 92 11 May-14 6 1.2 1.3 .010 .026 286 324 170 45 500 510 8.2 7.9 45 30 7.4 88 11 May-14 12 1.2 1.3 .006 .020 283 327 170 46 500 510 8.2 7.8 40 30 10.5 125 Ji/1 Aug-26 0 .78 .83 .006 .013 270 306 160 47 480 8.5 30 - 11 Aug-26 0 1.2 1.2 .029 .039 268 301 360 157 39 470 480 8.8 8.2 25 11 74 76 154 304 7.1 90 11 Aug-26 6 1.2 1.2 .029 .036 259 329 150 32 470 490 8.8 7.9 20 12 6.8 86 11 Aug-26 13 .76 .85 .033 .033 267 287 157 39 420 485 8.7 7.9 5 11 6.0 77 1/11 Jan-13 0 .59 .75 .020 .029 238 258 140 39 420 7.7 40 - 11 Jan-13 0 1.4 1.6 .059 .082 239 272 232 144 44 370 425 8.2 7.9 60 34 .58 9 1.5 7.5 18 - 11 Jan-13 7.5 1.9 2.1 .078 .095 239 266 141 40 381 415 8.2 8.0 60 35 8.5 73 11 Jan-13 15 2.5 2.8 .059 .088 249 278 150 47 380 440 8.2 7.9 70 36 10.2 88 1969 /12 Jan-14 0 .93 1.0 .003 .010 339 361 188 49 580 7.6 35 - 12 Jan-14 0 113 630 8.0 9 7 13 29 8.0 79 12 May-14 0 1.5 1.6 .016 .029 250 297 107 155 42 460 462 8.1 7.7 40 16 9 4 15 28 7.0 83 12 Aug-26 0 1.3 1.4 .046 .050 258 295 309 150 36 474 470 8.6 7.8 25 12 20 16 27 63 5.9 78 1970 12 Jan-13 0 1.7 1.9 .065 .088 229 275 210 139 37 370 400 8.2 7.7 80 32 12 0 6 18 8.8 81 12 Apr-21 0 1.2 .082 .085 167 214 112 35 310 310 8.4 7.1 60 - 12 Jul-16 0 .67 .033 .033 227 263 144 39 400 410 8.5 8.0 20 21 6.6 85 1969 13 Jan-16 0 .93 1.2 .020 .029 321 355 186 49 580 560 8.0 7.6 35 1 0 0 1 9.5 94 13 May-14 0 1.4 1.5 .016 .029 270 308 136 165 45 497 482 8.3 7.8 40 25 6 0 12 18 7.6 91 13 Aug-28 0 1.3 1.4 .020 .033 279 345 396 156 35 548 530 8.8 7.8 10 16 7.5 96 1970 13 Jan-14 0 1.3 1.7 .050 .059 284 323 217 165 48 460 492 8.2 7.6 33 '11 10 3 12 25 10.5 100 Table-13 Chemical Analyses of Water in Lake Okeechobee Continued (Results in milligrams per liter except as noted) Analysis made by U. S. Geological Survey Bicabonate Carbonate S(aHC03) (CO3) 1969 14 Jan-16 1305 15.3 14.5 0 16 5.0 0.07 49 14 41 2.9 172 156 46 63 0.3 0.2 0.003 0.08 14 May-14 1215 14.2 13 0 26 6.7 .02 50 13 41 2.8 166 160 48 64 .4 .07 .003 .09 14 Aug-28 0830 14.2 14 0 29 6.1. .03 43 13 43 3.0 124 148 14 42 64 .3 .02 .000 .05 1970 14 Jan-14 1500 15.9 16 0 12 6.6 .05 42 11 33 2.5 144 136 0 34 49 .4 .09 .003 .05 1969 15 Jan-16 1045 15.3 15 0 15 5.7 .05 50 15 44 3.0 188 164 48 66 .3 .2 .003 .03 15 May-14 1310 14.2 14.5 0 26 6.7 .01 52 14 45 2.8 170 168 8 50 68 .5 .02 .006 .01 rs Aug-28 1030 14.4 15 0 29 6,2 .03 47 14 43 3.1 140 156 14 42 65 .3 .02 .000 .05 1970 15 Jan-13 1300 15.9 16 0 11 7.2 .04 42 10 30 2.5 140 128 0 33 48 .3 .1 .006 .01 15 Apr-21 1200 15.6 31 8.7 40 10 31 2.4 126 33 45 .3 .4 .009 .12 15 Jul-16 0945 14.2 29 1.4 41 10 29 2.4 136 36 46 .4 .00 .000 .05 1969 16 Feb-18 0920 0 16 9.0 18 59 1.9 68 3.9 215 202 72 100 .5 .3 .006 .09 16 Mar-26 1200 0 20 5.2 .04 51 15 46 3.1 185 168 48 69 .5 .2 .000 .03 16 Apr-16 1050 0 24 6.2 .05 51 15 47 3.2 172 172 51 68 .4 .2 .000 .07 16 May-15 1550 0 30 6.7 .02 48 15 49 3.4 164 52 72 .3 .1 .003 .06 16 Jun-10 1450 0 33 2.6 .03 45 12 35 2.6 132 144 3 40 54 .5 .02 .003 .03 16 Jul-17 1100 0 32 7.6 .02 69 14 48 3.0 150 156 8 52 70 .5 .02 .003 .05 16 Aug-29 0930 14.4 0 29 17 .06 69 24 82 4.5 244 236 0 101 115 .5 .7 .079 .23 16 Sep-22 155 0 28 12 .04 49 15 49 3.1 172 164 52 72 .4 .2 .018 .27 16 Oct-28 1000 0 25 15 .02 46 14 45 3.1 168 152 47 70 .4 .2 .009 .03 16 Nov-20 1600 0 19 13 .04 50 16 51 3.2 194 170 60 76 .5 .3 .003 .09 1970 16 Jan-15 1043 15.9 0 12 7.1 .04 45 12 37 2.7 155 146 0 40 55 .3 .05 .003 .12 1969 17 Au 27 1000 14.4 4 0 29 3.5 .04 35 11 40 1.8 130 140 2 24 60 .3 .00 .000 .07 18 Aug-28 1200 14.4 3 0 30 5.4 .03 38 19 59 3.6 116 136 8 69 88 .3 .00 .000. .05 1970 18 Jan-15 1630 15.9 0 16 6.8 .01 40 10 30 2.3 121 126 6 35 46 .3 ,02 .006 .06 Table 13 Chemical Analyses of Water In Lake Okeechobee Continued (Results in milligrams per liter except as noted) Analysis made by U. S. Geological Survey g E DIdiv H nuas pH lue Ch orophyl Diolved SoUdld C CaCO3 28C ugh I I A 1969 14 Jan-16 0 2.0 2.2 0.029 0.029 299 328 180 52 540 525 8.1 7,6 40 8 8 14 30 9.4 94 14 May-14 0 1.0 1.2 .006 .016 305 337 195 179 48 535 550 8.3 7.8 30 30 5 0 5 7.5 92 14 Aug-28 0 2.0 2.1 .026 .036 287 331 420 161 40 548 530 8.8 7.8 10 19 46 3 96 145 7.0 90 1970 14 Jan-14 0 1.1 1.2 .033 .050 246 285 190 150 39 400 440 8.2 7.7 60 23 7 1 5 13 10 93 1969 15 Jan-16 0 1.4 1.7 .023 .029 314 350 186 52 567 555 8.1 7.7 30 5 2 0 7 9.6 94 15 May-14 0 1.1 1.1 .013 .010 322 368 103 187 50 555 570 8.6 8.0 30 37 3 0 0 3 8.2 100 15 AU 28 0 .77 .84 .023 .029 298 339 357 175 47 538 550 8.8 7.9 20 18 3 0 0 3 7.7 99 15 Jan-13 0 1.3 1,4 .050 .062 236 262 196 146 41 378 428 7.8 7.8 60 32 -12 4 14 30 8.5 77 15 Apr-21 0 .99 .042 ,052 234 270 141 38 420 420 8.6 7.9 60 - 15 Jul-16 0 .46 .026 .033 233 267 144 32 422 420 8.7 8.1 20 17 6.6 85 1969 16 Feb-18 0 .77 1.2 .042 .050 433 467 225 60. 680 730 8.1 7.7 45 -- 9.5 95 16 Mar-26 0 .94 1.2 .006 .029 322 360 189 51 570 579 8.2 7.7 40 8.5 92 16 Apr-16 0 .85 1.2 .006 .026 328 353 189 48 580 585 8.2 7.9 30 7.0 82 16 May-15 0 .87 1.1 .026 .042 328 367 182 47 573 590 7.8 20 7.5 99 16 Jun10 0 1.0 1.1. .020 .029 263 313 162 44 488 455 8.6 7.2 20 9.8 134 16 Jul-17 0 1.1 1.2 .020 .029 321 379 180 52 620 550 8.5 7.6 30 6.5 88 16 Aug-29 0 2.0 3.0 .042 .050 532 596 271 77 870 925 8.0 7.9 60 5.3 68 16 Sep-22 0 1.9 2.4 .042 .050 334 380 184 50 575 600 7.5 7.6 20 5.0 63 16 Oct-28 0 1.0 1.2' .050 .055 316 346 173 48 540 550 7.8 8.0 20 -- 7.0 83 16 Nov-16 0 1.2 1.6 ..052 .062 355 389 191 52 530 624 7.9 8.2 45 8.5 90 1970 16 Jan.15 0 1.3 1.5 .033 .036 271 310 162 43 445 481 8.2 7.8 50 9.8 91 1969 17 Au 27 0 1.0 1.1 .020 .029 246 293 582 133 18 458 460 8.3 7.7 40 7 19 0 74 93 7.2 92 1969 18 Au -28 0 1.2 1.2 .006 .010 349 404 294 173 62 563 650 8.6 7.8 30 10 0 0 0 0 7.3 96 1970 18 Jan-15 0 .91 1.0 .023 .033 233 271 141 38 370 419 8.5 7.9 50 18 -- -- 8.7 87 Table 14 Chemical Analyses of Water in Tributaries to Lake Okeechobee (Results in milligrams per liter except as noted) Analysis made by U. S. Geological Survey Bicarbonate S5(HC03) Station Name | I I 1969 Fisheating Creek Jan-15 1215 48 16 1.4 .19 8.8 3.5 20 5.9 25 1.6 40 0.2 0.02 0.003 0.09 Feb-17 1700 72 18 1.2 .15 15 3.8 25 3.1 37 41 2.0 48 .3 .02 .015 .38 Mar-25 1435 680 24 1.7 .21 7.9 3.3 15 1.6 16 16 4.8 29 .3 .02 .006 .06 Ap-15 1615 44 26 23 .30 9.4 3.6 17 .5 26 26 .4 31 .2 .02 .015 .16 May-6 0925 7.6 27 2.8 .18 12 4.2 16 .3 34 35 6.8 31 .5 .00 .009 .09 Jun-10 1745 31 31 2.6 .20 14 3.1 14 .8 38 42 4.0 24 .3 .00 .012 .06 Jul-16 1600 74 32 5.1 .41 5.7 2.5 10 .2 14 14 .0 20 .4 .00 .009 .08 Aug-27 1345 225 30 4.3 .24 7.7 2.4 11 .2 18 20 4.0 18 .2 .4 .009 .09 Sep-23 0900 320 28 5.1 .29 8.2 2.7 13 .4 24 23 .0 24 .3 .02 .006 .24 Oct-27 1620 1600 25 6.1 .51 7.3 2.3 9.7 1.0 24 17 .0 17 .2 .00 .009 .03 Nov-21 0930 1100 15 3.5 .22 6.4 2.4 12 .5 14 14 .0 26 .2 .5 .012 .11 Dec-9 1650 125 19 2.8 .13 7.7 2.7 14 1.1 42 18 .8 30 .3 .2 .006 .03 1970 Jan-14 1050 1150 12 2.7 .12 4.8 2.2 13 1.3 6 10 .0 24 .6 .00 .003 .09 1969 32 Harney Pond Canal Jan-15 1200 0 15 2.9 .30 36 8.8 24 2.5 78 44 43 .2 .1 .003 .03 Feb-17 1620 0 18 1.2 .12 19 9.1 26 2.7 00 102 39 42 .4 .09 .018 .09 Mar-25 1420 0 23 2.7 .10 26 5.3 13 2.1 24 22 46 22 .4 .09 .003 .12 Apr-15 1545 0 26 3.7 .07 25 6.7 19 1.8 58 58 40 31 .2 .05 .034 .05 May-6 1000 0 27 5.2 .20 18 6.2 15 2.2 44 44 49 23 .3 .05 .009 .05 Jun-10 1805 0 30 3.1 .09 21 4.3 13 2.2 30 34 32 22 .3 .02 .003 .09 Sep-23 0945 4010 29 7.3 .40 5.0 11 1.4 26 28 45 18 .2 ..2 .012 .23 1970 25 Jan-16 0945 0 13.5 6.3 .24 5.7 11 2.3 22 20 61 20 .3 .1 .009 .54 1969 19 Indian Prairie Canal Jan-15 1145 0 16 4.2 .24 5.5 11 3.6 26 44 20 .2 .2 .003 .11 Feb-17 1545 0 18 4.3 .21 30 6.9 16 3:2 59 58 50 26 .2 .3 .009 .12 Mar-25 1420 0 22 5.1 .21 4.7 1.0 15 2.8 22 16 139 23 .3 .05 .058 .76 Apr-15 1420 0 25 3.7 .09 47 9.5 20 1.9 66 64 95 33 .3 .4 .030 .14 May-16 1025 0 27 3.4 .10 14 4.0 8.8 6.5 20 21 32 14 .2 .00 .006 .05 Jun-10 1825 0 30 4.7 .24 36 6.1 17 2.8 74 72 46 30 .4 .02 .009 .18 1970 Jan-16 1000 0 15.5 3.0 .28 21 4.2 15 2.9 30 29 36 26 .2 .07 .012 .20 Table 14 SChemical Analyses of Water In Tributaries to Lake Okeechobee Continued (Results in milligrams per letter except as noted) _Analysis made by U. S. Geological Survey D w _oe iudnu o . ?Sa Cat pH value Dbuovd Station Nwme ^ i | ^ | ] ^ I | J J | I-_ fj i l iii Fisheating Creek Jan-IS 1.7 1.8 0.10 0.12 94 146 36 16 203 191 6.5 120 10.0 100 Feb-17 .92 1.4 .052 .075 119 172 53 20 227 235 7.0 6.8 120 10.0 105 Mar-25 .74 .83 .052 .085 72 127 33 20 145 143 6.4. 6.3 200 6.0 71 Apr-IS 2.1 2.3 .052 .098 78 140 39 17 154 158 6.9 6.3 240 7.0 85 May-16 1.5 1.6 .029 .039 91 146 48 19 165 173 6.8 6.7 160 7.5 93 Jun-10 1.2 1.3 .039 .059 .84 131 48 14 135 157 7.1 6.7 160 5.9 79 Jul-16 1.2 1.3 .050 .072 51 110 25 13 80 95 6.2 6.2 200 4.5 61 Aug-27 1.3 1.8 .046 .052 60 92 29 13 90 107 6.6 6.6 180 3.3 43 Sep23 .23 51 .059 .065 65 127 32 13 104 122 6.7 6.6 200 6.5 82 Oct-27 1.0 1.0 .072 .088 53 102 28 14 100 100 6.5 6.3 160 5.0 60 Nov-21 1.1 1.8 .023 .042 60 108 26 15 95 119 5.8 6.6 220 9.0 88 Dec-09 1.0 1.3 .036 .055 70 117 30 15 140 135 7.0 6.5 200 7.0 74 1970 Jan-14 .86 .95 .036 .050 54 103. 21 13 115 110 5.2 6.3 120 1969 Harney Pond Canal Jan-15 1.4 1.5 .042 .055 196 260 116 52 353 340 6.9 140 10.1 99 Feb.17 56 .76 .026 .050 207 241 128 44 360 379 7.5 7.3 100 10.0 105 Mar-25 1.0 1.2 .036 .085 122 155 70 52 215 216 6.9 6.5 120 7.6 87 Apr-15 2.1 2.2 .023 .050 158 201 93 45 295 285 7.6 7.7 100 7.5 92 May-16 .81 .92 .072 .075 149 192 88 52 256 264 6.9 7.1 100 55 68 Jun-10 .86 .98 .039 .055 112 146 63 35 132 192 6.5 6.7 80 5.5 72 Sep 23 .22 .64 .072 .085 124 160 73 50 196 210 6.6 6.8 120 3.0 38 1970 . Jan-16 .1.1 1.8 .10 .11 143 206 86 70 240 242 6.3 6.6 160 9.3 88 1969 Indian Prairie Canal Jan-I1 1.2 1.5 .039 .059 122 169 70 48 215 210 6.4 140 8.0 80 Feb-17 .42 .88 .052 .052 167 202 104 56 270 282 7.3 7.1 100 10.0 105 Mar-25 1.4 2.3 .006 .026 252 324 159 146 408 398 65 6.4 140 6.4 73 Apr-IS 1.6 2.2 .026 .050 244 296 157 104 418 405 7.5 6.6 100 6.8 81 May-6 .84 .90 .052 .052 93 120 52 35 121 160 6.5 6.5 80 5.5 68 Jun10 .88 1.1 .14 .15 179 232 115 56 131 292 6.9 6.8 100 5.4 71 1970 Jan-16 1.8 21 .16 .18 124 168 70 46 230 222 6.7 6.8 100 7.5 74 Table 14 Chemical Analyses of Water in Tributaries to Lake Okeechobee Continued (Results in milligrams per liter except as noted) Analysis made by U. S. Geological Smvey Bicarbonate a (HC03)Z 6 I S z. ? Station Name E S 5 I' Q 3 a D a 3 - 1969 Kissimmee River Jan-15 1125 1060 16 4.6 0.15 36 5.4 15 1.8 92 32 26 D.2 0.2 0.003 0.04 Feb-17 1500 794 17 2.0 .17 28 5.2 17 2.6 84 80 24 29 .3 .1 .018 .10 Mar-25 1320 3940 22 2.0 .13 26 2.5 8.0 1.4 66 64 15 13 .2 .02 .006 .08 Apr-15 144S 2640 25 1.9 .11 26 2.8 8.8 1.0 80 54 21 16 .3 .05 .012 .03 May-13 1515 1730 26 3.9 .14 26 2.9 9.3 1.1 72 72 14 16 .2 .1 .006 .03 Jun-10 1845 1120 29 3.8 .08 24 3.4 11 1.2 66 66 15 18 .3 .02 .012 .02 Jul-16 1430 116 32 4.5 .11 24 5.9 18 1.8 66 62 27 29 .4 .00 .015 .03 Aug-26 1515 3060 32 4.1 .17 14 3.2 8.8 1.3 34 28 17 14 .2 .02 .009 .12 Sep23 1100 2480 29 6.7 .24 30 3.3 11 1.2 86 85 16 22 .3 .1 .006 .23 Oct-27 1500 5920 25 4.3 .17 18 2.5 7.7 1.3 46 46 5.2 14 .2 .02 .012 .07 Nov-21 1045 5040 18 3.0 .15 16 2.0 7.2 1.1 46 42 11 14 .3 .02 .006 .06 Dec-09 1550 1300 18 3.2 .15 18 2.4 8.0 1.1 46 46 14 16 .3 .02 .021 .08 1970 Jan-14 1015 8950 9.5 2.4 .17 14 2.1 7.7 1.4 36 36 8.0 13 .6 .02 .009 .08 1969 Taylor Creek Jan-15 1045 14 14 6.5 .06 53 17 52 3.6 175 57 79 .4 3 .006 .09 Feb-17 1400 16 16 4.5 .16 74 22 111 7.5 167 165 86 212 .4 .5 .021 .35 Mar-25 1245 43 23 4.8 .24 26 5.2 23 4.9 78 63 17 40 .4 .2 .030 .43 Apr-15 1400 12 25 3.3 .15 39 7.4 28 3.7 119 108 26 47 .4 .2 .024 .19 May-13 1700 121 29 7.5 .38 33 9.0 46 4.5 74 65 37 87 .4 .3 .058 .28 Jun-10 1305 16 30 7.2 .10 49 13 66 5.0 124 120 48 121 .4 .09 .015. .26 Jul-16 1330 15 34 6.6 .21 37 8.9 39 3.8 102 97 34 71 .5 .09 .015 .31 Aug-26 1430 333 30 8.5 .34 26 6.9 38 3.1 66 55 24 76 .3 .2 .027 .36 Sep-22 1300 40 30 8.1 .26 26 5.2 28 3.0 60 59 19 54 .3 .2 .018 .33 Oct-27 1400 136 25 8.6 .30 16 3.6 15 3.9 38 37 7.0 32 .3 .1 .015 .16 Nov-20 1400 97 19 4.8 .18 21 3.9 17 3.2 60 56 12 36 .4 .07 .015 .09 Dec-09 1500 0 18 1.3 .18 37 8.0 39 4.1 96 92 28 79 .4 .3 .030 .26 1970 Jan-14 0945 47 11.5 5.6 .17 24 5.4 25 4.0 62 58 20 46 .2 ..1 .0$ .26 0 0 2: s Table 14 Chemical Analyses of Water in Tributaries to Lake Okeechobee Continued (Results in milligrams per liter except as noted) Analysis made by U. S. Geological Survey N Diolved Harudna as Disolved aSolids CaD03 T"Ae" pH value oXyP Station Name S C v1 1969 Kissimmee River Jan-15 0.67 0.97 0.050 0.059 167 203 112 36 288 288 7.2 120 8.5 85 Feb-17 .56 .82 .072 .091 148 185 92 26 265 267 7.3 7.2 110 10.1 103 Mar-25 .78 .89 .052 .078 100 116 76 23 149 180 7.9 7.0 120 7.4 84 Apr-15 .65 .74 .062 .098 105 124 77 32 177 183 7.8 7.3 80 7.0 83 May-13 .48 .66 .068 .11 109 144 77 18 179 200 7.9 7.4 80 7.0 85 Jun-10 .65 .71 .039 .055 110 144 74 20 195 190 7.6 6.8 70 6.9 89 Jul-16 .94 .99 .029 .042 142 180 85 34 266 245 7.7 6.9 70 7.2 97 Aug-26 .87 1.0 .042 .052 77 119 48 25 150 150 6.8 7.0 80 4.9 66 Sep-23 1.9 2.3 .088 .098 134 176 89 19 220 246 7.6 7.2 140 5.0 64 Oct-27 1.3 1.4 .062 .072 77 115 56 18 145 142 7.3 7.3 90 6.4 76 Nov-21 .63 .73 .075 .091 76 107 48 14 111 143 7.0 7.5 120 8.5 88 Dec-09 .60 .72 .065 .078 86 113 55 18 170 158 8.0 7.1 120 7.5 79 1970 Jan-14 .83 .94 .065 .072 68 105 44 14 112 125 8.1 6.9 120 - 1969 Taylor Creek Jan-15 1.7 2.1 .17 .18 357 401 202 59 573 625 7.4 40 8.5 82 Feb-17 .60 1.5 .98 .98 604 697 275 140 1750 7.6 7.4 60 9.0 90 Mar-25 .49 1.1 .98 1.1 156 189 87 35 288 285 7.0 6.9 220 4.5 52 Apr-15 .45 .88 59 .59 211 243 128 40 388 386 7.6 7.4 100 6.0 71 May-13 1.3 2.0 .95 1.1 261 355 120 66 497 485 7.3 7.0 120 6.2 80 Jun-10 1.3 1.7 .072 .075 371 478 176 78 750 660 8.1 7.0 70 8.1 106 Jul-16 1.3 1.7 .55 .55 251 317 129 50 462 438 7.7 7.1 100 5.5 76 Aug-26 .98 1.6 .49 .52 213 286 94 48 405 400 6.8 7.0 100 4.4 58 Sep-22 1.9, 2.4 .055 .059 175 219 87 39 462 315 6.9 7.0 130 5.0 66 Oct-27 1.0 1.3 .91 .91 108 155 55 25 204 190 6.0 6.7 140 4.0 48 Nov-20 .72 .90 .55 .55 128 156 69 23 197 236 7.0 7.6 120 8.0 85 Dec09 1.1 1.7 .62 .68 245 293 126 51 490 453 7.4 7.6 130 7.4 78 1970 Jan-14 .83 1.3, .59 .62 162 208 82 35 271 300 7.0 7.1 100 - Table 14 Chemical Analyses of Water in Tributaries to Lake Okeechobee Continued (Results in milligrams per liter except as noted) Analysis made by U. S. Geological Survey Bicarbonate (HC03) cVIE Station Name g 1969 Nubbin Slough Feb-18 1140 17 4.7 0.15 40 11 37 3.9 130 128 39 65 0.4 0.05 0.012 0.07 Mar-26 1530 20 7.1 .34 22 6.1 23 3.0 65 57 22 38 .4 .00 .009 .48 Apr-16 1445 30 3.7 .10 38 8.8 30 2.8 114 120 34 47 .4 .00 .003 .12 May-13 1625 28 9.3 .15 35 10 33 3.7 104 93 38 55 .3 .02 .015 .85 Jun-10 1330 30 9.7 .20 25 6.4 25 5.0 78 63 21 42 .4 .02 .009 1.4 Jul-17 1450 35 11 .20 29 8.3 28 6.3 101 75 30 49 .4 .00 .015 1.6 Aug-26 1545 32 10 .35 17 4.2 16 2.7 48 41 20 27 .3 .3 .015 .49 Sep-22 1330 31 10 .53 13 3.4 15 2.3 38 40 6.8 28 .3 .4 .009 .48 Oct-28 1320 25 9.9 .40 14 4.2 17 3.4 42 37 10 33 .4 .00 .018 .63 Nov-20 1430 19 5.6 .30 13 3.5 14 2.8 40 35 8.0 28 .4 .3 .009 .45 Table 14 Chemical Analyses of Water in Tributaries to Lake Okeechobee Continued (Results in milligrams per liter except as noted) Analysis made by U. S. Geological Survey S Diuolved Haudneuou cas d m pH Dvalu Sods Ca CO3 tl P Oxyygn Station Name I I 8 1 O S.. 1969 Nubbin Slough Feb-18 .98 1.1 0.29 0.30 265 306 145 40 458 465 7.5 7.4 90 6.0 62 Mar-26 1.3 1.8 .36 .36 151 187 80 33 278 275 6.8 6.8 140 1.0 11 Apr-16 .87 .99 .18 .20 224 254 131 33 398 398 7.9 7.3 80 9.4 124 May-13 1.1 2.0 .42 .42 232 286 129 53 428 423 7.4 7.0 80 4.9 62 Jun-10 1.8 3.3 .68 .68 168 233 89 38 312 290 6.9 6.8 120 1.1 15 Jul-17 1.7 3.4 .85 .91 202 277 .107 45 425 358 7.4 6.6 100 9.0 127 Aug-26 1.3 2.1 .39 .43 120 158 60 26 188 195 6.6 6.7 160 2.8 38 Sep-22 .21 1.1 .36 .36 102 169 47 14 165 180 6.6 6.8 240 3.5 47 Oct-28 1.4 2.1 .65 .65 112 159 53 23 200 195 6.7 6.6 200 2.3 27 Nov-20 1.3 2.0 .042 .046 95 138 47 18 152 178 6.5 6.8 160 7.5 80 Table 15 Chemical Analyses of Water in Drainage Canals of Lake Okeechobee Continued (Results in milligrams per liter except as noted) Analysis made by U. S. Geological Survey Bicarbonate S(HCO3) E | Station Name a 1969 St. Lucie Canal Jan-15 1620 43 17 6.2 .06 55 17 51 3.5 182 55 77 .4 0.2 0.003 0.06 Feb-18 1050 43 17 6.4 .09 54 15 46 3.0 177 170 49 68 .4 .4 .012 .12 Mar-26 1440 6590 20 7.1 .05 52 15 48 3.2 196 174 51 69 .6 .4 .003 .02 Apr-16 1400 759 25 7.3 .00 52 14 45 2.8 161 166 50 69 .5 .2 .006 .05 May-14 1025 37 25 5.9 .08 42 12 34 2.9 148 142 40 54 .3 .07 .003 .09 Jun-10 1410 28 31 4.8 .01 46 11 36 2.6 146 148 39 56 .4 .05 .003 .08 Jul-17 1350 28 32 5.6 .02 43 11 34 2.6 128 136 34 53 .5 .02 .000 .13 Aug-29 1030 26 29 6.1 .02 43 12 40 2.9 124 144 40 60 .3 .05 .009 .18 Sep-22 1415 26 29 8.6 .11 50 8.1 34 2.9 152 149 34 52 .3 .2 .052 .08 Oct-28 1230 6090 25 11 .07 41 11 32 2.4 138 136 31 53 .3 .07 .006 .01 Nov-20 1530 6710 19 9.0 .10 40 9.7 27 2.7 140 123 30 46 A4 .2 .006 .01 1970 Jan-15 1130 1640 13.5 7.1 .17 55 7.5 34 2.7 174 156 28 58 .3 .1 .015 .16 1969 North New River Canal Mar-26 1045 1580 21 5.8 .04 59 16 53 3.1 223 208 53 74 .5 .09 .000 .05 Apr-16 0930 666 25 4.8 .04 56 16 52 3.0 192 188 54 74 .5 .05 .000 .07 Jul-17 0945 512 31 18 .07 83 33 93 5.0 284 286 126 132 .8 .02 .006 .11 Jul-29 1530 -2100 20 .08 100 41 122 5.8 340 163 170 .8 .07 .003 - Jul-31 1700 -2040 25 .07 114 49 110 5.7 400 179 154 .9 .02 .006 Deo-10 1000 -2040 20 29 .09 113 50 239 8.5 556 495 107 332 1.3 .99 .070 .71 1970 Jan-15 1000 -1980 14 26 .06 91 38 138 7.5 385 367 122 182 .8 .21 .043 .51 1969 West Palm Beach Canal Mar-26 1350 1030 20 5.7 .04 51 14 47 3.0 183 168 49 67 .5 .2 .003 .02 Apr-16 1240 615 24 6.6 .14 51 14 47 3.1 167 176 50 67 A4 .2 .003 .01 Jul-17 1220 507 32 5.8 .02 47 12 38 2.7 150 152 41 58 .4 .02 .000 .09 Aug-29 0945 409 29 7.1 .02 47 14 45 3.1 124 152 49 68 .3 .1 .015 .05 Oct-28 1100 786 25 16 .05 48 15 43 3.4 158 152 43 66 .3 .3 .009 .'2 1969 Miami Canal Mar-26 0915 1640 22 5.1 .03 60 16 54 3.1 100 196 48 75 .5 .1 .003 .06 Apr-16 0830 927 24 5.4 .04 53 15 51 3.0 179 184 52 73 .5 .07 .000 .03 Jul-20 1000 -2040 19 .06 86 34 96 5.4 300 118 134 .7 .2 .009 .10 0 V 0i h-3 0 -4 Table 15 Chemical Analyses of Water in Drainage Canals of Lake Okeechobee Continued (Results in milligrams per liter except as noted) Analysis made by U. S. Geological Survey Disolved Hardne as Co5S2 pH value Dsolved Solids C03CO3 MuJIO Oxygen Station Name St. Lucie Canal Jan-15 1.8 2.1 0.029 0.033 356 393 207 58 680 620 7.5 45 8.5 98 Feb-18 .17 .68 .033 .052 328 356 196 56 560 560 7.8 7.6 40 11.0 113 Mar-26 .81 1.2 .036 .10 334 377 191 49 580 595 8.2 7.5 40 8.8 96 Apr-16 1.4 1.6 .010 .023 323 359 187 51 575 580 8.5 7.3 40 9.5 113 May-4 .91 1.1 .033 .036 280 380 155 38 475 472 8.0 7.6 20 6.0 71 Jun-10 1.0 1.1 .029 .039 -269 316 160 39 488 460 8.2 7.1 25 7.5 100 Jul17 1.1 1.3 .033 .042 251 316 153 41 490 431 8.6 7.3 30 7.3 99 0 Aug-29 1.4 1.6 .036 .046 276 310 157 39 495 515 8.5 7.7 15 5.9 76 ' Sep.22 .84 1.2 .14 .15 299 360 159 36 473 470 7.6 7.4 80 6.0 77 Oct-28 1.0 1.1 .039 .042 249 280 148 36 445 440 8.0 8.0 40 6.7 80 Nov-20 .00 .18 .055 .065 226 256 140 39 338 398 7.9 8.1 60 9.0 96 1970 0 Jan-15 .88 1.2 .11 .11 271 323 168 41 475 488 7.8 7.7 50 9.0 86 1969 West Palm Beach Canal Mar-26 1.0 1.2 .006 .026 '321 368 185 47 570 584 8.2 7.5 30 8.8 96 Apr-16 .88 1.1 .000 .013 327 360 185 41 578 584 8.4 7.9 30 7.5 89 Jul-17 1.3 1.4 .026 .036 280 331 167 43 542 478 8.5 7.5 30 5.5 74 Aug-29 1.4 1.6 .042 .046 309 338 175 51 532 570 8.5 7.6 20 6.7 86 Oct-28 .69 1.1 .050 .050 311 342 182 57 535 540 7.9 8.0 30 6.5 77 1969 North New River Canal Mar-26 1.0 1.1 .006 .023 367 412 213 43 630 663 8.1 7.5 40 7.0 78 Apr-16 .94 1.1 .006 .016 354 394 206 52 620 640 8.2 7.9 30 6.4 76 Jul-17 2.1 2.2 .029 .039 632 755 343 108 1080 1000 8.4 7.7 90 5.5 73 Jul-29 790 859 418 140 1350 8.2 100 - Jul-31 835 949 486 158 400 8.0 140 - Dec-10 2.0 3.8 .17 .16 1160 1240 488 82 2010 1980 7.7 8.3 160 4.0 43 1970 Jan-15 2.9 3.7 .19 .20 788 875 384 83 1260 1340 7.8 7.8 120 4.5 43 1969 Miami Canal Mar-26 1.1 1.3 .006 .020 369 404 216 55 640 663 8.2 7.8 35 7.0 80 Apr-16 .84 .94 .013 .023 344 389 194 43 602 620 8.4 8.0 30 7.0 82 Jul-20 1.3 1.6 .029 .036 642 746 355 109 1100 8.0 80 - Table 15 Chemical Analyses of Water in Drainage Canals of Lake Okeechobee Continued (Results in milligrams per liter except as noted) Analysis made by U. S. Geological Survey Statio n Name BIcarbonate (HCO3) 9 } 5 Q I I 8 -4 Station Name g I 1969 Caloosahatchee Canal Mar-25 1535 4060 23 3.3 .01 49 12 39 3.7 142 142 46 62 0.5 0.05 0.006 0.09 Apr-15 1715 1600 24 2.5 .03 47 12 40 2.7 152 148 41 59 .5 .02 .000 .05 May-16 0900 2420 26 2.7 .05 45 12 35 2.4 140 138 45 54 .3 .00 .003 .09 Aug-27 1430 5450 30 7.4 .08 36 15 46 5.8 124 124 53 65 .3 .00 .003 .08 Oct-27 1700 4680 25 8.8 .17 32 10 30 2.6 106 110 27 48 .3 .00 .006 .12 Nov-21 0900 5490 18 6.1 .07 36 11 31 2.3 114 118 34 48 .4 .07 .000 .05 1970 Jan-14 1150 12 3.7 .08 29 6.8 22 1.9 84 82 24 35 .3 .00 .003 .09 O 0 I -4 Table 15 Chemical Analyses of Water in Drainage Canals of Lake Okeechobee Continued (Results in milligrams per liter except as noted) Analysis made by U. S. Geological Survey Diolved Hudneuus 3suo old sowHs CCC03 P uH valm Station N amez s i 1969 Caloosahatchee Canal Mar-25 1.0 1.2 0.039 0.055 286 336 172 56 518 520 7.6 7.2 70 5.4 62 Apr-15 .93 1.0 .010 .010 278 310 167 46 508 505 7.8 7.5 50 6.1 72 May-16 1.1 1.2 .050 .052 265 300 162 49 463 482 7.8 7.4 20 7.5 93 Aug27 1.4 1.5 .029 .033 290 325 152 50 520 525 7.7 8.1 60 5.2 68 Oct-27 .98 1.1 .023 .033 213 258 121 31 380 380 7.0 7.5 60 4.8 57 Nov-21 .83 .95 .020 .029 227 255 135 39 318 401 7.2 7.9 60 8.5 90 1970 Jan-14 .85 .94 .050 .059 163 204 101 34 298 298 7.5 7.4 80 - 2/ Negative sign indicates reverse flow. Table 16 Phytoplankton in Lake Okeechobee CONCENTRATION IN CELLS PER MILLIMETER JAN MAY AUG JAN APR JUL OCT JAN APR Site 1969 1969 1969 1970 1970 1970 1970 1971 1971 1 <50 800 <40 <40 - 2 <50 320 <40 <40 <20 60 2,100 2,400 80 3 <50 100 <40 <40 - 4 <50 1,200 <40 <40 - 5 <50 4,600 <40 <40 <20 105,800 108,500e 473,700e 220 6 <50 3,600 <40 <40 - 7 <50 1,450 <40 <40 - 8 <50 340 <40 <40 1,130 5,850 3,200e 218,900e 37,400e z 9 <50 170 <40 80 560 66,600 20,100e 200,600e 15,900e C 10 <50 860 <40 <40 - 11 <50 1,350 <40 <40 - 12 <50 240 <40 <40 7,500 12,500 3,200e 960e 2,300 13 <50 100 <40 <40 - 14 <50 270 <40 <40 - 15 <50 2,900 <40 <40 100 1,730 15,400e 1,220e 6,400 e-Estimated Table 17 Chemical and Biololgicd Analyses of Water and Bottom Sediments In Lake Okeechobee, Kiaaimmee River and Taylor Creek, October 1970.May 1972 (Results in milligrams per liter, except as noted) Analysis made by U. S. Geologocal Survey Station Name Lake Okeechobee Point No. 2 Point No. 5 Point No. 8 Point No. 9 Point No. 12 Point No. 15 Kissimmee River Taylor Creek Lake Okeechobee Point No. 2 Point No. 5 Point No. 8 Point No. 9 Point No. 12 Point No. 15 Kisimmee River Taylor Creek Lake Okeechobee Point No. 2 Point No. 5 Point No. 8 Point No. 9 Point No. 12 Point No. 15 Kissimmee River Taylor Creek 10-14-70 1045 14.2 10-14-70 1305 14.2 10-14-70 0915 14.2 10-14-70 0845 14.2 10-14-70 0935 14.2 10-14-70 1020 14.2 1-12-71 1235 125 1-12-71 1400 17 1-12-71 1045 12.9 1-12-71 1145 12.9 1-12-71 0925 12.9 1-12-71 0900 12.9 1-12-71 1000 12.9 1-12-71 1110 12.9 4-27-71 1430 0 4-27-71 0815 3.3 4-27-71 1100 11.1 4-27-71 1230 11.1 4-27-71 0900 11.1 4-27-71 0845 11.1 4-27-71 0945 11.1 4-27-71 1130 11.1 8-19-71 1215 3030 8-19-71 1330 462 Carbonate (C03) 0 I c z ?E J. I- 27.0 29.0 26.0 26.0 26.0 26.5 22.0 24.0 22.0 23.0 21.0 21.0 22.0 22.0 28.0 26.0 27.5 29.5 26.0 25.0 26.5 27.5 30.0 28.0 U.. 2 U, 8r 9.1 8.4 11 7.8 11 7.8 7.2 5.2 12 7.8 8.1 8.1 12 12 2.7 5.0 10.0 10.0 9.6 8.4 6.2 11 5.8 4.2 i 12 9.6 11 11 12 9.6 8.8 20 12 13 II 11 12 12 7.7 15 13 14 15 14 13 12 4.7 4.6 Bicarbonate (HC03) 140 132 148 142 154 142 128 173 156 148 144 144 160 148 96 176 166 168 168 168 166 168 57 52 I 2.6 2.4 2.4 '2.5 2.7 2.5 2.4 7.0 2.7 2.6 2.6 2.6 2.8 2.8 2.4 3.8 2.9 3.0 3.0 3.1 2.9 2.9 1.5 3.6 40 41 46 43 45 44 50 72 47 48 49 50 48 48 36 56 52 54 54 54 :54 53 23 23 33 30 31 31 37 33 30 110 36 35 35 35 37 36 27 53 38 40 40 41 39 38 15 21 :1 .9 49 44 47 46 52 48 52 200 54 54 52 52 58 54 44 84 58 60 60 62 63 58 26 40 0 0.4 .3 .3 .3 .4 .3 .2 .2 .3 .2 .3 .3 .3 .2 .3 .5 .4 .4 .4 .5 .4 .4 .2 .3 0 0 0 0 0 0 0 0 0 8 8 8 0 4 0 0 0 6 4 4 0 0 0 0 38 35 37 37 43 38 49 80 40 41 41 41 44 43 38 55 47 50' 51 49 48 47 26 20 0.002 0.003 .00 .003 .00 .018 .00 .003 .09 .009 .00 .006 .2 .006 .2 .030 .1 .009 .00 .006 .00 .006 .00 .006 .1 .009 .1 .012 .02 .018 .00 .012 .3 .015 3 .009 .2 .009 .00 .012 .2 .018 .3 .021 .3 .015 .3 .088 0.013 .013 .006 .010 .016 .013 .010 .17 .000 .006 .003 .006 .013 .006 .10 .21 .075 .072 .072 .078 .078 .095 .026 .18 0o 0 0 ' ~ ' T Table 17 Chemical and Biological Analyses of Water and Bottom Sediments in Lake Okeechobee, Kissimmee River and Taylor Creek, October 1970-May 1972 Continued (Results in milligrams per liter, except as noted) Analysis made by U. S. Geological Survey Dissolved Hardnes as c C Dissolved SSolids CaC03 m PH alue S 25cn Station Name S Z |6 Lake Okeechobee Point No. 2 10-14-70 0.61 0.67 0.020 0.050 254 282 151 36 445 450 8.3 8.1 20 15 7.6 94 2,00e Point No. 5 10-14-70 .63 .67 .013 .036 236 271 143 35 420 420 8.3 7.9 20 6 7.9 101 108,500e Point No. 8 10-14-70 .54 .58 .029 .052 260 274 161 40 445 450 8.2 8.0 20 4 7.8 95 3,200e Point No. 9 10-14470 .59 .61 .013 .046 249 283 154 37 435 440 8.2 8.0 20 7 7.8 95 20,100e Point No. 12 10-14-70 .57 .71 .026 .052 280 311 163 37 500 495 8.0 8.1 30 9 6.7 82 3,200e Point No. 15 10-14-70 .67 .71 .016 .046 254 284 151 34 450 450 8.4 8.0 15 13 7.4 91 15,400e Kissimmee River 1-12-71 .5 .76 .039 .050 260 313 160 56 475 464 8.1 8.1 80 6 1.2 8.5 97 Taylor Creek 1-12-71 1.0 1.6 .62 .78 580 696 260 120 1160 1080 7.7 8.0 60 12 2.2 6.8 80 - Lake Okeechobee Point No. 2 1-12-71 .52 .64 .026 1 .026 280 313 170 39 485 497 8.5 8.1 30 6 .0 8.7 99 2,400 PointNo. 5 1-12-71 .68 .71 .016 .016 283 310 170 39 478 497 8.8 8.4 30 10 1.4 9.3 107 473,700e Point No. 8 1-12-71 .62 .64 .016 .026 280 322 170 36 470 486 8.6 8.4 25 12 1.1 9.0 100 218,900e PointNo.9 1-12-71 .61 .64 .013 .029 280 314 170 39 460 486 8.6 8.4 30 13 1.1 9.0 100 200,600e Point No. 12 1-12-71 .57 .72 .033 .050 290 326 170 39 495 508 8.5 8.2 30 14 .9 8.7 99 960e PointNo. 15 1-12-71 .58 .75 .033 .039 290 319 170 42 490 497 8.5 8.3 30 20 1.1 8.6 98 1,220e Kissimmee River 4-27-71 .85 1.1 .023 .050 13 205 247 120 43 380 8.2 8.0 15 9 8.3 105 650 Taylor Creek 4-27-71 2.1 2.6 .17 .20 115 359 421 200 57 605 670 8.0 8.0 20 25 8.7 4.6 56 6,400 Lake Okeechobee Point No. 2 4-27-71 2.2 2.7 .050 .065 19 305 363 180 47 535 550 8.1 8.2 15 45 1.8 7.8 98 80 Point No. 5 4-27-71 1.8 2.3 .026 .039 40 322 362 190 55 565 560 8.4 8.4 15 30 1.4 8.9 116 220 Point No. 8 4-27-71 2.3 2.6 .026 .039 18 321 337 200 52 545 570 8.5 8.4 10 35 2.5 7.7 94 37,400e Point No. 9 4-27-71 .75 .95 .029 .046 22 319 357 190 48 550 570 8.6 8.3 15 40 1.3 7.3 87 15,900e Point No. 12 4-27-71 .82 1.2 .042 .059 72 309 333 190 52 530 550 8.3 8.2 20 80 2.6 7.2 87 2,300 Point No. 15 4-27-71 2.3 2.9 .055 .075 22 307 345 180 44 545 550 8.4 8.2 20 60 1.6 8.2 102 1,000 KissimmeeRiver 8-19-71 1.2 1.6 .14 .18 23 132 227 77 31 225 235 7.1 7.0 140 3 1.1 3.9 51 0 Taylor Creek 8-19-71 1.5 2.3 .85 .88 31 146 162 77 34 311 270 6.7 7.7 200 10 3.0 5.0 63 1,100 e/ estimated 0 i 0 z 00 j^ Table 17 Chemical and Biological Analyses of Water and Bottom Sediments in Lake Okeechobee, Kissimmee River and Taylor Creek, October 1970-May 1972 Continued (Results in milligrams per liter, except as noted) Analysis made by U. S. Geological Survey Bicarbonate Carbonate SP(HC03) (C03) Station Name t & J Lake Okeechobee Point No. 2 8-19-71 1040 12.0 28.0 1.6 50 14 45 3.1 164 176 38 0 50 66 0.4 0.00 0.006 0.07 Point No. 5 8-19-71 0920 12.0 28.5 7.9 42 17 '52 4.5 120 146 16 0 66 77 .5 .00 .006 .04 Point No. 8 8-19-71 0815 12.0 28.0 4.8 48 17 50 3.2 164 176 8 0 55 74 .4 .00 .006 .05 Point No. 9 8-19-71 1300 12.0 28.0 4.8 38 11 36 2.9 112 114 0 0 44 57 .3 .02 .009 .02 Point No. 12 8-19-71 1130 12.0 30.0 6.4 52 9.0 38 3.0 164 162 0 0 34 58 .4 .09 .018 .12 Point No. 15 8-19-71 1010 12.0 28.0 .6 52 14 44 3.0 160 166 12 8 50 64 .4 .00 .006 .08 Kissinmmee River 11-10-71 0940 349 24.5 4.0 15 4.4 11 1.7 24 30 0 0 29 20 .2 .2 .012 .06 Taylor Creek 11-10-71 1515 52 23.5 7.0 27 6.6 29 5.1 74 72 0 0 24 54 .3 .3 .058 .27 Lake Okeechobee Point No. 2 11-11-71 1200 14.4 21.5 6.3 60 18 53 3.8 232 216 12 0 66 80 .4 .1 .006 .04 Point No. 5 11-10-71 1130 14.4 23.0 3.7 42 12 36 3.1 132 140 8 0 46 56 .3 .00 .000 .02 Point No. 8 11-10-71 0845 14.4 23.5 4.4 46 14 42 3.3 160 160 0 0 48 65 .3 .00 .000 .02 Point No. 9 11-10-71 0800 14.4 23.5 3.9 42 12 37 3.2 144 148 0 0 42 59 .3 .00 .003 .04 Point No. 12 11-11-71 1330 14.4 23.0 6.6 47 8.0 28 4.2 144 152 0 0 34 46 .3 .3 .021 .10 Point No. 15 11-11-71 1030 14.4 21.5 3.4 49 16 46 3.5 184 176 8 0 50 70 .3 .00 .009 .06 Kissimmee River 2-02-72 1130 0 22.0 4.6 42 12 39 2.7 120 0 53 62 .3 .1 .009 .05 Taylor Creek 2-02-72 1345 21 23.0 4.1 56 17 68 4.8 168 0 64 110 .4 .09 .018 .12 Lake Okeechobee Point No. 2 2-02-72 1015 13.7 22.0 7.4 56 17 50 3.3 192 0 59 72 .4 .2 .012 .04 Point No. 5 2-02-72 1445 13.7 23.0 7.0 56 18 54 3.4 176 12 61 76 .4 .00 .006 .02 Point No. 8 2-02-72 0830 13.7 22.0 4.6 56 16 48 3.3 176 8 53 70 .4 .00 .012 .02. Point No. 9 2-02-72 0745 13.7 21.5 5.8 54 17 48 3.3 180 4 54 72 .4 .00 .015 .05 Point No. 12 2-02-72 0915 13.7 22.0 8.4 56 17 48 3.3 192 0 57 70 .4 .2 .018 .08 Point No. 15 2-02-72 1045 13.7 22.0 6.0 54 16 46 3.3 180 0 56 66 .3 .1 .018 .09 I I IF I - I I.I. Table 17 Chemical and Biological Analyses of Water and Bottom Sediments in Lake Okeechobee, Kissimmee River and Taylor Creek, October 1970-May 1972 Continued (Results in milligrams per liter, except as noted) Analysis made by U. S. Geological Survey Dissolved madness Sp .HDissolved SSolids CaC03 j PHWveu Oxygen Station Name i 1 O e n 3 1on10i Lake Okeechobee Point No. 2 8-19-71 1.5 1.6 0.010 0.036 13 317 300 180 39 560 580 8.5 8.3 20 20 1.0 6.8 86 950 Point No. 5 8-19-71 1.9 2.0 .010 ..029 25 339 426 175 56 583 610 8.7 8.3 50 62 1.1 7.0 89 3,000 Point No. 8 8-19-71 1.9 2.0 .010 .033 18 339 365 190 46 680 630 8.6 8.3 30 20 1.1 6.8 86 670 Point No. 9 8-19-71 2.5 2.6 .042 .078 18 250 305 140 47 450 450 8.2 8.0 55 15 2.6 7.3 92 54,600e Point No, 12 8-19-71 1.3 1.5 .10 .13 14 282 338 170 34 512 500 7.8 7.5 80 10 1.4 5.0 66 6,000 Point No. 15 8-19-71 1.4 1.4 .010 .036 12 318 381 190 28 562 580 8.6 8.4 20 15 1.3 7.2 91 1,600 Kissimmee River 11-10-71 .85 1.1 .046 .052 14 101 139 56 31 145 182 6.9 5.7 120 3 .8 6.5 77 200 Taylor Creek 11-10-71 1.6 2.2 .65 .65 24 191 251 95 36 330 353 7.0 6.0 320 10 1.8 3.5 41 1,600 Lake Okeechobee Point No. 2 11-11-71 2.2 2.4 .036 .039 16 394 449 224 108 660 704 8.5 6.5 50 45 .8 8.7 98 14,500 Point No. 5 11-10-71 1.8 1.8 .016 .026 15 268 316 155 40 485 486 8.5 6.2 100 7 1.6 8.7 100 47,200 Point No. 8 11-10-71 1.8 1.8 .016 .026 13 302 338 173 42 480 551 8.0 6.3 60 15 1.5 8.4 98 79,600 Point No. 9 11-10-71 1.6 1.6 .016 .033 13 272 311 155 33 450 490 8.2 6.6 60 10 1.8 8.5 99 29,200 Point No. 12 11-11-71 1.5 1.9 .19 .20 22. 251 299 151 26 441 7.5 6.1 240 10 .9 6.2 71 3,900 Point No. 15 11-11-71 1.9 2.0 .046 .046 12 325 367 189 45 750 592 8.5 7.4 50 45 2.3 8.5 96 56,000 Kissimmee River 2-02-72 1.1 1.3 .033 .052 14 275 284 150 56 500 480 7.6 7.9 70 5 1.1 9.3 106 2,450 Taylor Creek 2-02-72 1.1 1.3 .23 .27 16 409 422 210 72 830 740 7.4 7.9 60 8 2.1 9.3 107 950 lake Okeechobee Point No. 2 2-02-72 2.3 2.6 .050 .050 17 361 374 210 52 615 600 8.3 8.3 45 35 1.6 9.3 106 150 PointfNo. 5 2-02-72 2.7 2.7 .016 .026 24 375 382 220 52 690 640 8.6 8.7 45 8 1.4 9.5 109 15,700 Point No. 8 2-02-72 3.0 3.0 .026 .039 20 338 350 210 48 595 570 8.5 8.5 45 25 2.3 9.3 106 21,100 Point No. 9 2-02-72 3.0 3.1 .042 .055 19 344 362 200 51 625 600 8.5 8.4 45 35 1.7 9.6 108 11,900 Point No. 12 2-02-72 3.0 3.3 .052 .062 22 356 362 210 52 615 590 8.2 8.3 50 50 2.1 9.2 104 250 Point No. 15 2-02-72 3.0 3.2 .059 .062 24 337 348 200 53 580 560 8.3 8.3 70 50 1.5 9.3 106 1,250 e/ estimated Table 17 Chemical and Biological Analyses of Water and Bottom Sediments in Lake Okeechobee, Kissimmee River and Taylor Creek, October 1970-May1972 Continued (Results in mllg s per liter, except as noted) Analysis made by U. S. Geological Survey Bicarbonate Cabonat (HCO3) (0c3) Station N me H lip" Af It Kssinnee River 5-31-72 1750 875 28.0 2.0 14 4.4 13 1.9 29 30 0 0 26 21 0.3 0.00 .003 0.03 Taylor Creek 5-13-72 1745 41 29.0 2.5 60 19 90 5.1 160 156 0 0 72 160 .5 .02 .009 .04 Lake Okeechobee Point No. 2 5-31-72 1155 13.1 27.5 6.9 55 18 53 3.9 204 178 0 7 62 78 .5 .1 .003 .02 Point No. S 5-31-72 1300 13.1 27.5 7.2 54 18 54 4.0 184 162 6 11 62 84 .5 .00 .003 .03 Point No. 8 5-31-72 0800 13.1 26.5 4.2 54 16 51 3.8 198 172 2 5 58 76 .5 .00 .006 .04 Point No. 9 5-31-72 D715 13.1 26.5 2.7 52 15 47 3.6 148 158 12 7 56 74 5 .00 .003 .02 Point No. 12 5-31-72 1000 13.1 28.0 3.7 59 15 49 3.9 196 180 0 2 57 76 .5 .05 .006 .04 Point No. 15 5-31-72 0900 13.1 26.5 7.2 56 17 53 3.9 204 174 2 7 62 78 5 .00 .006 .02 |
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| MILLISECOND | CLASS.METHOD | MESSAGE |
|---|---|---|
| 0 | sobekcm_page_globals.constructor | |
| 0 | sobekcm_page_globals.constructor | Application State validated or built |
| 0 | sobekcm_database.verify_item_lookup_object | |
| 0 | sobekcm_page_globals.constructor | Navigation Object created from URI query string |
| 0 | sobekcm_database.verify_item_lookup_object | |
| 0 | sobekcm_page_globals.display_item | Retrieving item or group information |
| 0 | sobekcm_page_globals.get_entire_collection_hierarchy | Retrieving hierarchy information |
| 0 | sobekcm_assistant.get_entire_collection_hierarchy | |
| 0 | cached_data_manager.retrieve_item_aggregation | |
| 0 | cached_data_manager.retrieve_item_aggregation | Found item aggregation on local cache |
| 0 | item_aggregation_builder.get_item_aggregation | Found 'all' item aggregation in cache |
| 0 | system.web.ui.page.page_load (ufdc.page_load) | |
| 0 | sobekcm_page_globals.constructor.on_page_load | |
| 0 | html_echo_mainwriter.add_style_references | Adding style references to HTML |
| 0 | html_echo_mainwriter.add_text_to_page | Reading the text from the file and echoing back to the output stream |
| 235 | html_echo_mainwriter.add_text_to_page | Finished reading and writing the file |