CITY OF LAKELAND - University of South Florida...Lakeland Lakes Program during its first ten years...

CITY OF LAKELAND LAKES WATER QUALITY REPORT

1988-2000

Written By: City of Lakeland

Public Works Department Lakes & Stormwater Division

August 2001

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TABLE OF CONTENTS

I. Introduction 3 II. Geographical Settings 3 III. Named Lakes 4 IV. The Lake Life Cycle 4 V. Pollutants and Lakes 4 Are the Fish Safe to Eat? 7 Is it Safe to Swim in the Lakes? 7 Nutrients 7 Chlorophyll 8 Secchi 9 TSI 9 Water Levels 10 Metals 10 VI. Fish & Wildlife 11 VII. Role of Plants 11 Plant Management Programs 11 VIII. Comprehensive Lakes Plan 13 IX. Lake by Lake Information 14 Glossary 35

TABLES AND FIGURES Figure 1 - Map of Named Lakes Figure 2 - Hydrologic Cycle Map Table 1 - Lake Trophic States Table 2 - Average Annual Water Quality Data for 2000 Table 3 - Average Annual Water Quality Data for 1988-2000 Table 4 - Average Metal Concentrations for 2000 Table 5 - Average Metal Concentrations for 1988-2000 Table 6 - List of 38 named lakes

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I. INTRODUCTION This Lakeland Lakes Water Quality Report summarizes information collected by the City of Lakeland Lakes Program during its first ten years of lakes monitoring. In this report, we provide some useful information for lake users including boat ramp locations and depth soundings for the major lakes in the City. In addition, information on water quality pollution levels and trends is presented to provide the reader with a feel for the health of our lakes. In these cases, we have tried to explain the significance of the data. It should be noted that the science of lakes and rivers (limnology) is still relatively new, and there is much that is still not understood. As with all ecosystems, lakes are incredibly complex.

The City of Lakeland encompasses an area of approximately 28,000 acres and contains 38 named lakes and numerous smaller lakes. Among the 38 named lakes, sizes range from 2.5 acres (Lake Blanton) to 2272 acres (Lake Parker). Water discharged from these lakes flow through creeks, ditches and pipes to tributaries of three major river systems - the Peace River, the Alafia River, and the Hillsborough River.

Our lakes are invaluable to the citizens of Lakeland as they provide opportunities for recreation, sanctuaries for wildlife, and natural beauty. The importance of the lakes has long been recognized by Lakeland's citizens and civic leaders and was the primary reason for the creation of Lakeland's Lakes Program in 1987. All lakes have an economic value and contribute to a community's quality of life.

Prior to the establishment of the City of Lakeland Lakes Program, little information was available on our lakes. Some lakes had no documented water quality data. In 1988, a program was started to monitor water quality on 16 of the major lake systems in the City. This report summarizes the results of this effort. It is our hope that the report will provide information useful to the citizens that are interested in the ecology of these resources as well as those that use them for recreational activities.

II. GEOGRAPHICAL SETTING The City of Lakeland is located in west central Florida. The soils in this region are naturally rich in phosphorus, a major element needed for growth by plants. The rich phosphorus deposits in the soil have been mined since the turn of the century. It is important to note that soils in Lakeland differ significantly with those found in other parts of Polk County. Three ridges run through the County in a north-south direction. The Lakeland Ridge runs along the West side of the County, the Winter Haven Ridge through the center, and the Lake Wales Ridge along the East. The City of Lakeland is located on the top and eastern slope of the Lakeland Ridge.

In the eastern part of the County on the Lake Wales Ridge, the sandy, well-drained soils are typically nutrient poor. Lakes in this region generally have low concentrations of nutrients. These conditions support fewer plants and animals which result is clearer water. The rich, green-water lakes (as found in the Lakeland area) support a greater abundance of fish, and are therefore preferred by many fishermen. Clear water lakes are more aesthetically appealing, and are the choice of boaters, skiers and swimmers.

The combination of drainage basins that contain naturally rich soils, abundant rainfall (approximately 52 inches/year) that carries nutrients to the lakes, and a warm sub-tropical climate create the ideal environment for plant growth. Consequently, the lakes in Lakeland are naturally productive. This characteristic is discussed in more detail in Section V.

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III. NAMED LAKES Figure 1 shows the location of the 38 named lakes in Lakeland. Some of these lakes are located partially in the City and partially in the County. The official authority for naming lakes is the U.S. Board on Geographic Names. The Board is composed of representatives from Federal departments and independent agencies concerned with the use of geographic names. The nine downtown lakes in Lakeland received their names in various ways. Lakes Hunter, Parker and Hollingsworth were named after settlers living adjacent to the lakes. Mr. Munn (Lakeland’s founder) named Lake Morton after his brother-in-law. There is a discrepancy as to whether Lake Bonny (originally Boney) was named after an Indian fighter or after fish in the lake, which were bony. Lake Wire was named after the telegraph line poles that stood in its waters. Lake Bonnet was named after the water lilies growing in a narrow band along its shore. Lake Mirror was originally known as Deep Lake because of its depth, although others called it Lake Bushy because of the trees and heavy undergrowth that covered its shore. The current name was given to the lake because of the reflections seen at night around the lighted promenade.

IV. THE LAKE LIFE CYCLE Lakes undergo a life cycle that includes various stages from their formation to their eventual filling and return to terrestrial landscapes. In Florida, the vast majority of lakes are formed from sinkhole activity. Limestone, Florida's bedrock, is slowly dissolved by weakly acidic rainwater that percolates through the overlaying sand, clay and organic topsoils. In time, cavities in the limestone are formed, then collapse due to the Swiss cheese like bedrock that results in depressions on the land surface. Water from rainfall, groundwater seepage and in some cases surface sources (creeks and rivers) fill the depressions.

In most cases, newly formed lakes are nutrient poor and have clear water. As lakes age, nutrients, sediments and pollutants from the surrounding watershed migrate to the basin. Lake productivity increases with increased nutrient loading resulting in a reduction in water clarity. Basins slowly fill with soil and the remains of plants and animals. The rate at which a lake basin fills typically increases with age.

The process of lake aging through increasing productivity is termed eutrophication. An index to measure the degree of lake eutrophication (Trophic State Index – TSI) has been developed and has been calculate for sixteen of Lakeland's lakes. Lakes with a trophic state index value exceeding 70 are highly productive and have persistent algae blooms and poor water clarity (See Section V).

V. POLLUTANTS AND LAKES

The alteration of land by development for residential, agricultural or other uses changes the way water flows through the watershed to a lake or river. The replacement of vegetation with concrete and asphalt reduces the capacity of the land to cleanse or remove pollutants from water as it travels through the watershed to a lake. Figure 2 illustrates the hydrologic cycle and the movement of water through the environment. Pollutants that are released into the environment are carried by stormwater runoff, groundwater and the atmosphere to our lakes. As a result, our lakes are reservoirs for a variety of naturally occurring and man-made contaminants.

The most common pollutant problem in Lakeland and in many lakes throughout the world is over-enrichment. The discharge of nutrients from fertilizers and eroding soils has resulted in nutrient concentrations in lakes high enough to cause imbalances in plant and animal communities. The construction of stormwater systems that transport this enriched water directly to our lakes and streams has hastened the rate that lakes age. Without the benefit of treatment that comes with the natural sheetflow of water over native soils and vegetation, the pollutants contained in the

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Figure 1. Map of Named Lakes

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Figure 2. The Hydrologic Cycle

This cycle has no beginning and no end. The water that collects in oceans, lakes, rivers and reservoirs is continually evaporating under the heat of the sun. It rises into the air as vapor and floats silently into the atmosphere. When vapor cools, it condenses and returns to the earth as precipitation. In Florida, this usually takes the form of rainfall, which becomes runoff and again collects in large water bodies. A small amount percolates through the ground into the aquifers where it is stored as groundwater or moves underground toward the ocean. Even more is absorbed by plants and trees, to be released later through evapotranspiration and resume its looping journey upward in the form of vapor.

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runoff are discharged into our lakes. Stormwater runoff is now considered the greatest source of pollutant loading to Florida's lakes, rivers and estuaries.

Since the early 1980's, developments have been required to provide some degree of stormwater treatment prior to discharge offsite. Most of the City of Lakeland's stormwater system was constructed prior to any treatment requirements. These older systems will need to be outfitted with pollutant removal systems if long term water quality improvements are to be expected.

When nutrients are discharged into a lake at unnaturally high rates, lakes age faster. Nutrient concentrations in untreated urban runoff are typically ten to one hundred times higher than in runoff from similar undeveloped land. The rapid enrichment fuels algae blooms that cloud the water, cause changes in water chemistry, increase the rate at which the lake fills in, and disrupt other wildlife in the lake. Reversing over-enrichment is difficult and expensive. In lakes where eutrophication is advanced, such as Lake Hollingsworth, the sediments may be an important source of nutrient loading and must be removed before any improvements can be expected.

• ARE THE FISH SAFE TO EAT? Most of us who eat fish from urban lakes are concerned about their purity. The frequent news about fish consumption advisories issued by state and federal governments adds to the uncertainty. Fish from several lakes in Lakeland have been tested as part of special studies. Five species of fish were collected from the lakes representing a range of trophic groups from omnivorous (fish that eat both plant and animals) to top predators. The study determined that metals and organic concentration levels in the flesh of fish from Lake Hollingsworth are low and consumption does not appear to pose any threat to human health.

The State of Florida’s Health Department has tested many of Florida’s water bodies for mercury contamination. In a 1994-1995 advisory from the Game and Freshwater Fish Commission, Lake Parker was listed as a lake where consumption of fish is unrestricted. A 1983 study of Lake Wire and Lake Morton analyzed lead levels in fish flesh from these lakes and found the levels low.

• IS IT SAFE TO SWIM IN THE LAKES Standards for evaluating the safety of lakes for swimming involve the counting of Coliform bacteria. Coliform bacteria are a group of non-pathogenic bacteria that live in the digestive tracts of warm-blooded animals. The presence of these bacteria are thought to be indicative of contamination by pathogens. (See Tables 2 & 3)

The following parameters are used to regularly monitor the conditions of our City lakes:

A. NUTRIENTS Nutrients found in lakes, such as phosphorus and nitrogen, are critical for plant growth. Typically, nutrients are cycled in a lake through the process of plant production, decomposition of plant and animal matter through fungi and bacteria, and the ensuing release of nutrients. Some nutrients become part of the bottom sediments, some become available for plant growth, and some stay dissolved in the water column.

Nutrient enrichment can accelerate eutrophication, although the exact process is not completely understood. Nutrients entering a lake not only “fertilize” algae, increasing its production, they will also fertilize floating, submersed, and shoreline aquatic plants. Often with extensive growth of rooted aquatic plant growth, the water becomes clearer, although nutrient input has increased. The plants grow and use the nutrients, binding them either in the sediments or in the plant itself. Nutrients can cause a lake to become shallower as increased algae and plant production, and ensuing decomposition, add silt to lake bottoms. Layers of sediment accumulate over the years making the lake shallower, eventually turning the lake into a wetland. A nutrient rich lake will fill in faster than a lake

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with low nutrient levels. The process of natural eutrophication, the infilling of a basin as a lake ages, occurs over many thousands of years. Cultural eutrophication is the acceleration of a lake’s aging due to human activities and added nutrient inputs.

The City of Lakeland lies in a nutrient rich region known as the Bone Valley Formation. The soils in this area contain high amounts of phosphorus. Phosphorus and nitrogen are the two limiting nutrients in area lakes. Through the dissolution by rain and groundwater, Lakeland’s lakes have higher phosphorus values occurring naturally than most Florida lakes. In addition to urban stormwater runoff, nutrients such as phosphorus and nitrogen can enter the lake from many sources:

• rainfall directly on lakes; runoff from watersheds; • soils naturally containing phosphorus; • fertilizers applied to crops and yards; • treated waste from industrial processes, such as phosphate mining; • effluent from sewage treatment plants; • septic tanks; • auto exhaust; • bird and animal waste; • lawn and tree debris; • detergents containing phosphates.

Typically, nutrients are transported from one place to another by water, usually rainwater. Rainwater is not pure water. Even unpolluted air contains compounds that are picked up by rain. Air pollution adds even more substances to rainwater. Often compounds found in rain contain the nutrients phosphorus and nitrogen, along with other compounds such as sulfides which contribute to lake acidification. Lakes receive nutrients from rain directly and indirectly. When rain falls into lakes, the nutrients are received directly with the rainfall. Lakes also receive nutrients from rain that has fallen on land and has picked up added nutrients on the way. Surface runoff is rain that falls on the ground and flows overland. This runoff then picks up nutrients from yards, woods, roadways and parking lots. Stormwater runoff is the rain which flows quickly from impervious areas such as roads, parking lots and buildings carrying with it particles, debris, and automobile waste products. Nutrient laden water can also reach the lakes by traveling underground. Subsurface runoff flows through rocks or soils which can have high nutrient concentrations, it can then seep into lakes or enter them as springs. In the case of Lakeland’s lakes lying in the phosphoric Bone Valley Region, the nutrient is phosphate. Nutrients can also seep out of septic tanks and flow underground to lakes. Treated sewage (effluent) which comes out of sewage treatment plants is extremely high in nutrients. As populations increase, some areas have resorted to disposing of their effluent in wetlands or other water bodies, or by pumping it into the ground or spraying it on fields. No matter how one disposes of the effluent, the nutrients can still flow overground or underground to a lake.

B. CHLOROPHYLL

Chlorophyll is the green pigment in plants that not only imparts color but makes it possible for photosynthesis to occur. Chlorophyll is possibly the most frequently used estimator of algal biomass in lakes and streams, at least in the United States. Algal production (biomass) is controlled by water temperature, light availability, nutrient availability, hydraulic residence time (the time required for the lake volume to replace itself), and consumption by animals. When enough light is available for photosynthesis, the availability of nutrients is often the controlling factor. Usually phosphorus and nitrogen are the least available nutrients, so they become the limiting factors in algal production. The by-products of modern living are high in these sources of nutrients. Wastewater, fertilizers, agricultural drainage, detergents, and municipal sewage contain high concentrations of phosphorus and nitrogen, and if they enter a lake, they will stimulate algal productivity.

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C. SECCHI A Secchi Disk is a flat horizontal white or white with alternating black quadrants disk that is lowered from a rope into the water until it disappears from view. The standard Secchi disk used in fresh water systems is an eight-inch black and white disk. The depth of the water column where a Secchi Disk can no longer be seen is a measure of the transparency of the water. Transparency is affected by the color of the water and by suspended particles of silt, clay, or algae. Transparency can be a measure of some sorts of pollution. Limnologists (Lake Managers) tend to think of water quality in terms of the amount of algae, weeds (aquatic plants), silt and turbidity in a water body. Out of 114 Polk County lakes sampled in 1997 by Polk County Natural Resources staff, average Secchi disk values ranged from 0.2 m (8 inches) to 4.0 m (13 feet). Lakeland has 38 named lakes 16 of these lakes are routinely sampled for water quality. Average Secchi disk values in 1997 for Lakeland lakes ranged from 0.23 m (9 inches) to 3.7 m (12 feet). The lowest Secchi readings were in Lake Hollingsworth; the highest readings were in Lake Wire. Lake Wire’s extensive growths of submersed aquatic plants influence Secchi depth and water clarity.

D. TSI TSI is an acronym for trophic state index or indices. Various indices are available to evaluate measured in-lake variables so that the extent of eutrophy (aging) or degradation can be compared to other lakes in the area. Trophic state indices provide a quantitative means of assessing lake changes by simplifying complex environmental measurements. The basis for using a trophic state index is that, in many lakes, the degree of eutrophication is related to increased nutrient concentrations in the lake. The assumption follows that an increase in lake phosphorus concentrations leads to an increase in algal biomass as measured by chlorophyll a, which would result in a decrease in water transparency as measured by Secchi disk.

The Carlson (1977) Trophic State Index (TSI) is the most widely used and best known. Since 1977, several additional trophic state indices have been developed that rely on Carlson’s approach. However, while many of these indices have similar features, most of them were derived from data on temperate lakes. For this reason, Carlson’s Index or the other recent indices should not be applied directly to Florida Lakes. Studies on subtropical and warm-temperate Florida lakes argue that relationships among Secchi Depth (SD), Total Phosphorus (TP), and chlorophyll a are unique for Florida lakes. The development of a Florida TSI by the University of Florida in 1983, takes into account multiple variables and represents an average of the physical, chemical and biological components of the trophic state theory. Many Florida lakes are nitrogen limited, while the Carlson Index assumes that lakes are phosphorus limited.

The Florida trophic state index uses sub-indices for Secchi Depth, Total Phosphorus, Total Nitrogen, and chlorophyll a. Average TSI’s were developed depending on whether a lake is phosphorus limited, nitrogen limited, or relatively nutrient balanced. Since an increase in plant biomass is a measure of eutrophication (enrichment), plant biomass indicators were selected as components of the sub-indices. To determine algal biomass, an index based on chlorophyll was developed. The Florida TSI uses percent macrophyte (large aquatic plants) coverage as the index for macrophyte biomass. There are subjective problems in dealing with percent macrophyte cover, since the index does not qualify submergent vs. floating or native vs. exotic plants. The primary problem with using macrophyte coverage as an index is that macrophyte abundance and chlorophyll a appear to be independent of each other in Florida lakes.

The main point of using a TSI to classify Florida lakes for management purposes, is the selection of a critical value for the TSI. That is, deciding the value above which a lake is likely to exhibit eutrophication or enrichment problems. Huber et. al. (1983) in a comparison of 573 Florida lakes discovered that 411 of the lakes had TSI’s of 60 or below. These 411 lakes seemed to have less urgent problems. Of the remaining 162

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lakes compared, 90 problem lakes were identified with TSI’s greater than 60. Of the 90 problem lakes, several lakes are well known as enriched or “troubled” lakes: such as Apopka, Hancock, Thonotosassa and Okeechobee. In conclusion, Huber et. al., assumed that a TSI of 60 is the cut-off for Florida lakes, above which enrichment becomes a problem. The formula to calculate TSI was adopted by the State of Florida and is outlined in the State’s 1996 305(b) report: ChlA TSI = 16.8 +(14.4 x LN (CHLA))

TN TSI = 56 + (19.8 x LN (TN)) TN2TSI = 10 x (5.96 + 2.15 x LN (TN + .0001)) TP TSI = (18.6 x LN (TP x 1000)) – 18.4 TP2 TSI = 10 x (2.36 x LN (TP x 1000) – 2.38)

Limiting nutrient considerations for calculating NUTR TSI: If TN/TP>30 then NUTR TSI = TP2 TSI If TN/TP<10 then NUTR TSI = TN2 TSI If 10<TN/TP<30 then NUTR TSI = (TP TSI + TN TSI)/2 TSI= (CHLA TSI + NUTR TSI)/2 Where CHLA TSI = Trophic State Index based on Chlorophyll a TN TSI = Trophic State Index based on Total Nitrogen TP TSI = Trophic State Index based on Total Phosphorus NUTR TSI =Trophic State Index based on Total Nutrient Budget TN2TSI = Alternate equation used depending on limiting nutrient TSI = Trophic State Index TN = Total Nitrogen concentration (mg/L) TP = Total Phosphorus concentration (mg/L) CHLA = Chlorophyll a concentration (ug/L) LN = Natural Log

0 - 49 (BEST) Oligotrophic 50 - 59 (GOOD) Mesotrophic 60 - 69 (FAIR) Eutrophic 70 - Above (POOR)

E. WATER LEVELS Florida is a water state. Not only is the state surrounded by water on three sides, but much of South Florida from the Kissimmee River Basin to the Everglades was a wetland prior to development. Florida lakes respond to rainfall, evaporation, surface water flows, and ground water flows by changes in water level. Sometimes these changes are small (2 feet) sometimes extreme (30 feet). As a result of man’s activities, many lakes are not allowed to fluctuate naturally. Water level stabilization is considered one of the major causes of undesirable changes in lake and wetland ecosystems. Fluctuation can allow a return to near normal water level condition, and assist in maintaining good water quality.

F. METALS The use of metals in many of the products we use in our society has resulted in the contamination of surface waters. Potential sources of metals in surface waters are stormwater runoff and illicit dumping or industrial discharge. The pH of a lake can also influence the concentrations of metals found in the water column. Metal concentrations in stormwater runoff can be significant. The City of Orlando conducted a study of metals in stormwater runoff and found that detectable levels of cadmium, copper, lead, and zinc are commonly found in stormwater runoff. These heavy metals are generated from sources such as wear from automobile parts or atmospheric deposition and are carried to lakes by stormwater runoff (1996 Lake Water Quality Report – City of Orlando). For the 16 lakes sampled by the City of Lakeland Lakes Program for metals, all usually fall within the

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allowable parameters established by Florida Administrative Code (F.A.C.) 62-302.530 Criteria for Surface Water Quality Classifications, except lead (See Tables 4 & 5). Lead is routinely high in approximately half of the cities lakes. Lead is very soluble, and as mentioned above, pH can be a factor in high lead levels. As the pH increases, lead will fall out of solution and into sediments. Once pH decreases, the lead will dissolve out of the sediments and back into the water column.

VI. FISH & WILDLIFE Wildlife Resources Central Florida’s numerous lakes and adjacent wetlands provide support for a multiple diversity of wildlife. Wading birds are probably the most conspicuous of the various species seen. Approximately 30 species of wading and migratory birds have been found living in and around Lakeland’s lakes. Historically Florida has supported a large population of water birds. Florida is important as a stopover for migratory birds fleeing the cold winters in temperate climates. Lake Parker has a large migratory bird community in the winter months, several species of wintering ducks can be observed from the shore. Lake Hollingsworth is home to a large community of white pelicans, which can be seen swimming, feeding, and flying with synchronous precision from December to April.

Expanding human populations has increased habitat destruction by alteration of water levels and depletion of valuable shoreline. Wildlife habitat and aquatic plant communities are intricately linked in Florida’s lakes. Vegetation around the shoreline and in the water provides shelter and food for many small animals inhabiting the riparian zone around our lakes. Small mammals such as marsh rabbits, muskrats, otters, mice etc. make their homes around our lakeshores. In addition to birds and mammals, Lakeland’s lakes are also home to a large variety of reptiles and amphibians ranging from the top predator, American Alligator, to the green tree frog. Although Lakeland’s lakes are urban, they provide a valuable greening effect with vegetation buffers and walking paths. In the midst of an urban setting, our lakes provide an opportunity to see and enjoy wildlife and a respite from the noise and clamor of the city.

VII. ROLE OF PLANTS Aquatic plants are an important component of Florida's over 7,500 freshwater lakes. Fish and wildlife populations depend on aquatic plants. Aquatic plants in turn affect water quality and help to prevent shoreline erosion. Aquatic plants provide refuge and nursery for small animals. They play a role in the uptake and storage of nutrients, and they prevent erosion by binding soils and buffering suspension of sediments from wave and wind activity. Generally, lakes with diverse and abundant macrophyte (plants excluding the algae) cover contain a more diverse community of invertebrates and fish. Some fishery biologists feel that aquatic plants should occupy 50% of a lake's volume to produce an optimum fish community.

Emergent plants can grow in water depths of up to 10 feet or more. Most aquatic plants are very specific for the depth of water in which they will grow. For example, cord grass generally grows in +1.5 to −0.5 feet of water, Pickerelweed grows in −0.5 to −3.0 feet of water, and Giant Bulrushes grow in −3.0 feet to 5.0 feet of water. Often light penetration and water clarity control the depths at which submerged plants will grow. Dense beds of submerged plants can compete with algae for nutrients and cause the water in a lake to be clear. Lake Wire is a good example of this.

PLANT MANAGEMENT PROGRAM Because aquatic plants are beneficial, managers try to maintain an abundant and diverse community of plants in our lakes. However, in many lakes, conditions are such that nuisance growth will occur if not controlled. The Florida Department of Environmental Protection regulates the control (removal, trimming, transplanting, etc.) of aquatic plants in Florida. There are several exotic and nuisance species of aquatic plants in Florida. The exotic species have no natural enemies, so they often flourish – out competing natives and choking waterways. The State of Florida spends millions of dollars annually controlling exotic aquatic vegetation.

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There are three basic methods for controlling plants. These include mechanical (harvesting, hand removal), chemical (herbicide application), and biological (plant consumers such as the grass carp). Often an integrated program will be used to control plants on a lake. • Mechanical Control:

The City owns and operates two aquatic plant harvesters. Mechanical harvesters are used for the removal of floating vegetation; cattails, hydrilla, American lotus and other target plants. Hand removal is sometimes required for thinning beds or removing vegetation in sensitive areas.

• Chemical Herbicides: All herbicides used by the City of Lakeland's state certified applicators are federally approved for aquatic use. Herbicides are available for controlling emergent and submerged plants as well as algae.

• Biological: Sterilized grass carp are the best-known biological control agents used in Florida lakes. Metal grates with rebars 1 ½” X 1 ½” squares are placed at the waterbody outfall structures to prevent the fishes from escaping. The amount of fishes placed in a lake is determined by the FGFWFC based on the lake acreage and the amount of vegetation in the lake. These fishes live for many years. Biological control is a slow process in managing aquatic vegetation. There are several other agents, mostly insects, that feed on aquatic plants. The alligator flea beetle has been very effective in controlling alligator weed commonly found around shorelines. Researchers are still investigating other host specific biological controls.

The City of Lakeland Lakes Program manages aquatic plants in open water areas and along shorelines that are accessible to the public. Polk County Natural Resources Division receives funding from state and federal agencies for controlling Water Hyacinths, Water Lettuce and Hydrilla in lakes with public boat ramps. In Lakeland, these include Lakes Hollingsworth, Parker, Bonny, Gibson, and Hunter. A continuous Aquatic Plant Management maintenance program exists within the Lakes Division for all city lakes. The following is a brief explanation of what has occurred within each lake, to date:

Lake Bentley: Herbicide application was conducted to control Hydrilla, Water Lettuce and Water Hyacinth. Grass carp was introduced to assist in Hydrilla control.

Lake Beulah: Almost 65% of the lake was covered with Hydrilla and Alligator Weed. Mechanical harvesting was used to control hydrilla. In 1989 sonar (a herbicide) was applied to control Hydrilla. Today there is no Hydrilla in the lake. Extensive revegetation was done along the shoreline; some clusters of Nuphar were planted in the lake.

Lake Bonny: Visibility into Lake Bonny along Main Street was limited due to Cattails and Primrose Willow. Two acres of unwanted vegetation were herbicided, burned and mechanically removed. This 1000-foot shoreline was completely revegetated with desirable vegetation. City staff continues to chemically treat American Lotus.

Lake Bonnet: The west shoreline along Brunnell Parkway was completely covered with Cattails and Primrose Willow, allowing limited visibility in the lake. The 1.5 acres was controlled through herbiciding, burning, harvesting and hand removal. The shoreline has been completely revegetated. Occasionally staff would harvest floating mats of uprooted vegetation. About 7 acres of Water Hyacinth and Water Lettuce are herbicided 3 times a year.

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Lake Holloway: The dominant vegetation is Hydrilla, Coontail and Maidencain. Both chemical and biological methods are used to control the vegetation. Presently the lake is stocked with 150 grass carp.

Lake Hollingsworth: The entire shorelines were covered with cattails and primrose willow. Removal was by herbiciding, mechanical and hand removal over several years. At the same time revegetation was done in small sections. There are 42 acres of American lotus in the lake. Twenty acres are continuously herbicided during the months of April – August. Harvesting occurs every November-December. Grass carp still remains in the lake. All visible portions of the lake have been revegetated

Lake Horney: The surface area was covered with Hydrilla. Control/removal was by mechanical harvesters. In late 1989, herbicide was used which eradicated all Hydrilla. Some fragrant Water Lilies and Nuphar were planted in the lake.

Lake Hunter: All shoreline vegetation from Cresap to the east of the boat ramp was completely removed and revegetated with funding from the Florida Game and Fresh Water Fish Commission. More than one third of the surface area was covered with American Lotus. There has been no regrowth of Lotus since the spring of 1997.

Lake Mirror: Torpedograss and Primrose Willow covered the entire shoreline, while Hydrilla covered most of the lake surface. After herbiciding, a crane and clampshell removed most of the vegetation. Harvesters removed Hydrilla. Almost all of the Hydrilla has been removed due to herbiciding. Lake Parker: Between 1987 and 1992, 23 acres of Cattail, Primrose and other vegetation along Memorial Boulevard and West Lake Parker Drive were herbicided, burned, mechanically (dragline, dozers, clampshell) and hand removed. As required by permit, revegetation was complete in 1993. The City continues to harvest floating mats of vegetation and regularly herbicide for American Lotus, Water Lettuce, Water Hyacinth and some Hydrilla.

Lake Wire: The vegetation along the shoreline was Cattail, Primrose Willow, Paragrass, Torpedograss and Elephant Ears. Most of the vegetation was removed and revegetated over a three-year period. The City harvested approximately 7-8 acres every October during 1986-1998. The lake has been stocked with 1500 grass carp. More than 65% of the lake is currently covered with Hydrilla.

VIII. COMPREHENSIVE LAKES PLAN In 1996, the City of Lakeland prepared a 20-year Comprehensive Lakes Management Plan. The plan listed the existing programs associated with Lake Management and the costs of these programs. It identified new projects needed to improve water quality in our lakes, and estimated the funding required to implement these projects over the next 20 years. In order to develop a schedule for implementing the new projects, the major lakes in Lakeland were priortizied based on need for improvement, on recreational usage and public access. Both in-lake restoration projects and stormwater treatment projects are included in the plan. The study also looked at different ways to fund the management plan. A stormwater utility was recommended as the most

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fair and equitable method. A stormwater utility fee charges customers a monthly user fee based on land use and runoff characteristics. This was adopted in December 1999.

IX. LAKE BY LAKE INFORMATION

General information on the 16 monitored lakes in Lakeland is presented in the following section. Bottom contour (Bathymetric) maps show the depths in each lake as well as boat ramp locations. Nutrient and chlorophyll a (algae) concentrations, and secchi depths (water transparency) give the reader an indication of the richness or productivity of each lake. These measurements are used to calculate the Trophic State Index value (TSI) (see Section V above for detailed explanation). The actual TSI values are plotted graphically, and a trend line is created from a linear regression calculation. Table 1 below provides a scale for each trophic state classification. All the lakes in Lakeland have characteristics associated with eutrophic or hypereutrophic systems.

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Table 1. Lake Trophic States (adapted from Forsberg and Ryding, 1980)

Trophic Class

Typical Characteristics

Water Clarity (Feet)

Chlorophyll (Algae) (ug/L)

Total Phosphorus

(ug/L)

Total Nitrogen (mg/L)

Oligotrophic Low nutrients, clear water, few plants

Greater than 13 Less than 3 Less than 15 Less than 0.04

Mesotrophic Moderate nutrients, dominated by plants or algae, good water clarity

8 – 13 3 - 7 15 - 25 0.04 - 0.06

Eutrophic High nutrients, frequent algae blooms and/or dense grass beds, moderate to poor water clarity

3 – 8 7 - 40 10 - 25 0.06 - 1.5

Hypereutrophic High nutrients, persistent algae blooms, poor water clarity

Less than 3 feet Greater than 40

Greater than 25

Greater than 1.5

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LAKE BENTLEY Location: Latitude 28° 00 ‘ 51 “ N Longitude 81° 55 ‘ 35 “ W Section 29, Township 28 S, Range 24 E Drainage Basin Area: 9437.28 km2 (2319.33ac) Lake Surface Area: 210.44 km2 (51.87ac) Mean Depth: 2.2 m (7.2 ft) Lake Volume: 469,527 m3 (124,049,033gal) Shoreline Length: 2,818 m (9,246 ft) Basin Land Use: Residential 72%, Commercial 11%, Open 17% Historic Low Water Elevation: 113.0 NGVD 1999 Low: 113.58 NGVD 2000 Low: 113.1 NGVD Historic High Water Elevation: 115.6 NGVD 1999 High: 114.92 NGVD 2000 High: 114.46 NGVD Normal Pool: 114.25 NVGD

(Historic High: COL, 1997; Historic Low: COL, 1995; Elev. values include readings from: November, 1993 to December, 2000) 2000 Water Quality Data: Minimum Maximum Average Total Phosphorus (mg/L) 0.299 0.468 0.360 Total Nitrogen (mg/L) 1.32 1.76 1.49 Chlorophyll-a (µg/L) 41 91 58 Secchi Depth (m) 0.42 0.62 0.52 TSI 68 77 71 Total Coliform Bacteria (#/100 ml) 10 400 140 Fecal Coliform Bacteria (#/100 ml) 1 50 15 Long Term Water Quality Data: 12/88-12/00: Minimum Maximum Average Total Phosphorus (mg/L) 0.020 0.250 0.232 Total Nitrogen (mg/L) 0.76 5.74 2.47 Chlorophyll-a (µg/L) 5 112.2 63 Secchi Depth (ft/m) 0.35 0.80 0.46 TSI 58 88 75 Total Coliform (#/100 ml) 1 19500 1083 Fecal Coliform (#/100 ml) 1 360 41 Trophic State Index:

Comments: Lake Bentley was created in the 1950’s by phosphate mining. It receives inflow from Lake Hollingsworth via Hollingsworth Creek and discharges to Lake Somerset and the Peace River via Banana Lake and Lake Hancock. Grass Carp was introduced in 1994 for hydrilla control. No public access, the boat ramp is private. A new water control structure was installed 1997. Recreational activities include fishing and boating. ✷✷✷✷ Watershed includes Hollingsworth, Morton and Horney systems.

LAKE BENTLEY

TSI

TSI ValueTrend

12/88 12/90 12/92 12/94 12/96 12/98 12/0058

63

68

73

78

83

88

17

LAKE BEULAH

Location: Latitude 28 ° 02 ‘ 26 ” N Longitude 81° 58 ‘ 06 ” W Section 24, Township 28 S, Range 23 E Drainage Basin Area: 315.66 km2 (79ac) Lake Surface Area: 68.80 km2 (17ac) Mean Depth: 5.0 m (16.5 ft) Lake Volume: 354,230 m3 (93,587,566gal) Shoreline Length: 1,002 m (3,287 ft) Predominant Drainage Basin Land Use: Residential 37%, Commercial 10%, Open 53% Historic Low Water Elevation: 174.73 NGVD 1999 Low: 177.77 NGVD 2000 Low: 177.11 NGVD Historic High Water Elevation: 181.45 NGVD 1999 High: 181.45 NGVD 2000 High: 179.55 NGVD Normal Pool: 178.50 NVGD

(Historic High: 1999; Historic Low: 1991; Elevation values include readings from November, 1987 to December, 2000)

2000 Water Quality Data: Minimum Maximum Average Total Phosphorus (mg/L) 0.140 0.205 0.160 Total Nitrogen (mg/L) 0.63 1.56 1.00 Chlorophyll-a (µg/L) 10 75 30 Secchi Depth (m) 0.63 1.65 1.24 TSI 55 64 60 Total Coliform (#/100 ml) 20 200 118 Fecal Coliform (#/100 ml) 2 70 39 Long Term Water Quality Data: 12/88-12/00: Minimum Maximum Average Total Phosphorus (mg/L) 0.001 0.35 0.101 Total Nitrogen (mg/L) 0.47 3.82 1.50 Chlorophyll-a (µg/L) 0.1 75 25 Secchi Depth (m) .48 5.0 1.60 TSI 14 78 60 Total Coliform (#/100 ml) <1 400,000 7864 Fecal Coliform (#/100 ml) <1 400 40 Trophic State Index:

Comments: Lake Beulah is the deepest natural lake within the City - 28 feet. Lake Beulah had extensive Hydrilla infestation in the 1980’s; Grass Carp and herbicides were used to control Hydrilla. Lake Beulah discharges to the Alafia River via Lake Hunter. Recreational activities include fishing, picnicking and walking path.

LAKE BEULAH

TSI

TSI ValueTrend

12/88 12/90 12/92 12/94 12/96 12/98 12/0040

50

60

70

80

90

18

LAKE BONNET Location: Latitude 28 ° 02 53 N Longitude 81° 58 ‘ 36 “ W Section 14, Township 28 S, Range 23 E Drainage Basin Area: 3322.47 km2 (820.04ac) Lake Surface Area: 319.70 km2 (79.04ac) Mean Depth: 0.9 m (2.9 ft) Lake Volume: 293,047 m3 (774,230,174gal) Shoreline Length: 2,241 m (7,351 ft) Predominant Drainage Basin Land Use: Residential 43%, Commercial 16%, Open 41% Historic Low Water Elevation: 142.10 NGVD 1999 Low: 144.02 NGVD 2000 Low: 143.88 NGVD Historic High Water Elevation: 146.62 NGVD 1999 High: 145.70 NGVD 2000 High: 144.96 NGVD Normal Pool: 144.25 NGVD

(Historic High: COL, 1988; Historic Low: COL, 1997; Elevation values include readings from November, 1987 to December, 2000)

2000 Water Quality Data: Minimum Maximum Average Total Phosphorus (mg/L) 0.178 0.305 0.245 Total Nitrogen (mg/L) 1.27 3.50 2.48 Chlorophyll-a (µg/L) 46 103 70 Secchi Depth (m) 0.25 0.63 0.44 TSI 70 84 77 Total Coliform (#/100 ml) <100 400 163 Fecal Coliform (#/100 ml) 10 40 33 Long Term Water Quality Data: 12/88-12/00: Minimum Maximum Average Total Phosphorus (mg/L) 0.20 8.47 0.540 Total Nitrogen (mg/L) 0.97 22.3 4.66 Chlorophyll-a (µg/L) 11 1338 182 Secchi Depth (m) 0.05 0.70 0.31 TSI 49 123 84 Total Coliform (#/100 ml) 1 8600 582 Fecal Coliform (#/100 ml) 1 1000 59 Trophic State Index:

Comments: Lake Bonnet has an extensive marsh bordering the east shoreline. The lake is a shallow enriched system. Historical photographs show thick mats of Water Hyacinths covering the surface of the lake. A drawdown and sediment removal project was attempted in 1975. It was unsuccessful due to problems with dewatering the lakebed. Brunnell Parkway forms a dike along the west shore. Recreational activities include fishing.

LAKE BONNET

TSI

TSI ValueTrend

12/88 12/90 12/92 12/94 12/96 12/98 12/0049

69

89

109

129

19

LAKE BONNY Location: Latitude 28 ° 02 ’ 21” N Longitude 81 ° 55 ‘ 38 “ W Section 20, Township 28 S, Range 24 E Drainage Basin Area: 4657.94 km2 (1151.02ac) Lake Surface Area: 1501.39 km2 (370.5ac) Mean Depth: 0.9 m (3.2 ft) Lake Volume: 1,475,940 m3 (389,943,348gal) Shoreline Length: 7,599 m (24,930 ft) Predominant Drainage Basin Land Use: Residential 37%, Commercial 27%, Open 36% Historic Low Water Elevation: 123.12 NGVD 1999 Low: 128.72 NGVD 2000 Low: 125.82 NGVD Historic High Water Elevation: 133.50 NGVD 1999 High: 130.68 NGVD 2000 High: 129.72 NGVD Normal Pool: 130.00 NGVD

(Historic High; USGS, 1959; Historic Low: SWFWMD, 1956; Elevation values include readings from September, 1988 to December, 2000) 2000 Water Quality Data: Minimum Maximum Average Total Phosphorus (mg/L) .297 .640 .439 Total Nitrogen (mg/L) 3.68 5.46 4.41 Chlorophyll-a (µg/L) 67 146 105 Secchi Depth (m) 0.25 0.28 0.27 TSI 82 88 86 T_COLI (#Col/100 ml) <100 400 188 F_COLI (#Col/100 ml) 10 260 96 Long Term Water Quality Data: 12/88-12/00: Minimum Maximum Average Total Phosphorus (mg/L) 0.005 1.07 0.215 Total Nitrogen (mg/L) 0.74 7.2 2.76 Chlorophyll-a (µg/L) 9 378 76 Secchi Depth (m) 0.20 1.1 0.49 TSI 45 91 73 Total Coliform (#/100 ml) 1 13400 624 Fecal Coliform (#/100 ml) 1 260 42 Trophic State Index:

Comments: Lake Bonny and Little Lake Bonny were naturally land-locked and disconnected seepage lakes. These lakes were connected to each other and Lake Parker by canals in the mid 1920’s. Lake Bonny’s surface area includes Little Lake Bonny and the marsh on the west side of the lake. A public park and boat ramp is located on the north shore of the lake. Fishing, boating and picnicking are allowable recreational activities. Another park on the west shore is in the planning phase. Preliminary plans include a boat ramp, and boardwalk. Bonny receives inflow from Lake Holloway via a pipe.

LAKE BONNY

TSI

TSI ValueTrend

12/88 12/90 12/92 12/94 12/96 12/98 12/0059

69

79

89

99

20

LAKE CRAGO Location: Latitude 28 ° 05 ‘ 34 ” N Longitude 81° 56 ‘ 52 “ W Section 31, Township 27 S, Range 24 E Drainage Basin Area: 11679.24km2 (2884.96ac) Lake Surface Area: 210.44 km2 (51.87ac) Mean Depth: 4.0 m (13.0 ft) Lake Volume: 842,053 m3 (222,470,403gal) Shoreline Length: 2,576 m (8,951 ft) Predominant Drainage Basin Land Use: Residential 30%, Commercial 3%, Open 67% Historic Low Water Elevation: No Gauge 1997 Low: No Gauge Historic High Water Elevation: No Gauge 1997 High: No Gauge Normal Pool: No Gauge 2000 Water Quality Data: Minimum Maximum Average Total Phosphorus (mg/L) 0.189 0.290 0.258 Total Nitrogen (mg/L) 1.71 2.53 1.96 Chlorophyll-a (µg/L) 28 77 55 Secchi Depth (m) 0.51 0.92 0.70 TSI 68 79 74 Total Coliform (#/100 ml) 5 610 191 Fecal Coliform (#/100 ml) 1 212 60 Long Term Water Quality Data: 12/88-12/00: Minimum Maximum Average Total Phosphorus (mg/L) 0.035 0.913 0.270 Total Nitrogen (mg/L) 0.94 5.50 2.18 Chlorophyll-a (µg/L) 19 166 63 Secchi Depth (m) 0.30 1.30 0.66 TSI 61 85 75 Total Coliform (#/100 ml) 1 2200 130 Fecal Coliform (#/100 ml) 1 212 11 Trophic State Index:

Comments: Lake Crago was created during phosphate mining in the 1960’s. Lake Crago receives inflow from Lakes Gibson and Deeson, and discharges to Lake Parker and the Peace River. Lake access is via a canal connecting Lakes Parker to Crago. Lake Crago contains Hydrilla and is considered a good fishing lake. Recreational activities include fishing. ✷✷✷✷ Includes Lake Gibson watershed.

Lake Crago

TSI

TSI ValueTrend

12/88 12/90 12/92 12/94 12/96 12/98 12/0060

65

70

75

80

85

21

LAKE GIBSON Location: Latitude 28 ° 06 ‘ 31 “ N Longitude 81 ° 57 ‘ 33 “ W Section 25, Township 27 S, Range 23 E Drainage Basin Area: 10137.38 km2 (2502.11ac) Lake Surface Area: 1982.96 km2 (489.06ac) Mean Depth: 2.0 m (6.6 ft) Lake Volume: 3,888,927 m3 (1,027,454,513 gal) Shoreline Length: 10,467 m (34,340 ft) Predominant Drainage Basin Land Use: Residential 35%, Commercial 4%, Open 61% Historic Low Water Elevation: 140.20 NGVD 1999 Low: 136.00 NGVD 2000 Low: 141.60 NGVD Historic High Water Elevation: 145.40 NGVD 1999 High: 142.86 NGVD 2000 High:142.39 NGVD Normal Pool: 142.60 NGVD

(Historic High: SWFWMD, 1985; Historic Low: COL, 1993; Elevation values include readings from September, 1988 to December, 2000) 2000 Water Quality Data: Minimum Maximum Average Total Phosphorus (mg/L) .208 .344 .268 Total Nitrogen (mg/L) 0.59 1.02 .765 Chlorophyll-a (µg/L) 4 6 6 Secchi Depth (m) .85 1.78 1.16 TSI 45 49 47 Total Coliform (#/100 ml) 5 40 14 Fecal Coliform (#/100 ml) 1 10 3 Long Term Water Quality Data: 12/88-12/00: Minimum Maximum Average Total Phosphorus (mg/L) 0.63 1.2 .268 Total Nitrogen (mg/L) 0.10 3.71 1.18 Chlorophyll-a (µg/L) 0.70 93 13 Secchi Depth (m) 0.45 1.78 0.98 TSI 36 81 54 Total Coliform (#/100 ml) 1 3600 155 Fecal Coliform (#/100 ml) 1 110 8 Trophic State Index:

Comments: Lake Gibson is a colored (tannic acid) lake receiving drainage from the southern reaches of the Green Swamp. Lake Gibson has the highest water quality of all City of Lakeland lakes. Ongoing development within the watershed threatens lake conservation. There is a county park and boat ramp on southeast shore of lake. Mayflies, which require excellent water quality for survival, emerge from the lake in the spring, and can be observed on buildings and lights near the lake. Recreational activities include fishing and boating.

LAKE GIBSON

TSI

TSI ValueTrend

12/88 12/90 12/92 12/94 12/96 12/98 12/0031

41

51

61

71

81

22

LAKE HOLLINGSWORTH Location: Latitude 28 ° 01 ‘ 30 “ N Longitude 81 ° 56 ’ 44 “ W Section 30, Township 28 S, Range 24 E Drainage Basin Area: 6673.27 km2 (1647.49ac) Lake Surface Area: 1436.63 km2 (358.15ac) Mean Depth: 1.2 m (3.6 ft) Lake Volume: 1,713,180 m3 (452,622,156 gal) Shoreline Length: 4,557 m (14,950 ft) Predominant Drainage Basin Land Use: Residential 57%, Commercial 3%, Open 40% Historic Low Water Elevation: 125.68 NGVD 1999 Low: 130.28 NGVD 2000 Low: 125.68 NGVD Historic High Water Elevation: 133.21 NGVD 1999 High: 132.14 NGVD 2000 High: 129.95 NGVD Normal Pool: 130.50 NGVD

(Historic High: COL, 1991; Historic Low: COL, 2000; Elevation values include readings from April, 1988 to December, 2000) 2000 Water Quality Data: Minimum Maximum Average Total Phosphorus (mg/L) 0.272 0.600 0.449 Total Nitrogen (mg/L) 2.56 4.97 3.37 Chlorophyll-a (µg/L) 115 179 140 Secchi Depth (m) 0.20 0.49 0.33 TSI 83 91 86 Total Coliform (#/100 ml) 50 1800 775 Fecal Coliform (#/100 ml) 5 1000 420 Long Term Water Quality Data: 12/88-12/00: Minimum Maximum Average Total Phosphorus (mg/L) 0.015 0.640 0.251 Total Nitrogen (mg/L) 0.75 12.2 4.07 Chlorophyll-a (µg/L) 27 368 164 Secchi Depth (m) 0.15 0.60 0.29 TSI 60 101 85 Total Coliform (#/100 ml) 1 17200 1469 Fecal Coliform (#/100 ml) 1 8000 516 Trophic State Index:

Comments: Lake Hollingsworth is one of the most popular recreational lakes in Polk County. Over 2,000 people per day use the lake and shoreline for recreation. Grass Carp was introduced to control Hydrilla. The lake experiences high bacteria counts, which restricts lake use in the winter. Fifty-seven stormwater outfalls pipes discharge into the lake. The City is in the process of restoring the lake profile through hydraulic dredging of the organic sediment deposits. A park and boat ramp are located on the southwest shore. The lake has been stocked with Sunshine Bass. Recreational activities include fishing and boating, picnicking and walking path. ✷✷✷✷ Includes Lake Morton and Lake Horney watersheds.

LAKE HOLLINGSWORTH

TSI

TSI ValueTrend

12/88 12/90 12/92 12/94 12/96 12/98 12/0060

70

80

90

100

110

23

LAKE HOLLOWAY

Location: Latitude 28 ° 02 ’ 04 “ N Longitude 81 ° 55 ‘ 01 “ W Section 21, Township 28 S, Range 24 E Drainage Basin Area: 1205.96 km2 (298.87ac) Lake Surface Area: 97.12 km2 (23.96ac) Mean Depth: 2.0 m (6.6 ft) Lake Volume: 206,465 m3 (54,548,053 gal) Shoreline Length: 1,223 m (4,105 ft) Predominant Drainage Basin Land Use: Residential 67%, Commercial 8%, Open 25% Historic Low Water Elevation: 138.10 NGVD 1999 Low: 138.10 NGVD 2000 Low: 136.36 NGVD Historic High Water Elevation: 140.32 NGVD 1999 High: 139.00 NGVD 2000 High: 138.32 NGVD Normal Pool: 139.00 NGVD

(Historic High: COL, 1998; Historic Low: COL, 1999; Elevation values include readings from November, 1993 to December, 2000) 2000 Water Quality Data: Minimum Maximum Average Total Phosphorus (mg/L) 0.128 0.177 0.147 Total Nitrogen (mg/L) 0.65 0.814 0.738 Chlorophyll-a (µg/L) 3 9 6 Secchi Depth (m) 2.22 3.10 2.68 TSI 43 50 47 Total Coliform (#/100 ml) 5 100 64 Fecal Coliform (#/100 ml) 2 5 4 Long Term Water Quality Data: 12/88-12/00: Minimum Maximum Average Total Phosphorus (mg/L) 0.001 0.602 0.071 Total Nitrogen (mg/L) 0.30 3.9 1.20 Chlorophyll-a (µg/L) 0.40 21 7 Secchi Depth (m) 0.70 4.0 2.34 TSI 10 70 47 Total Coliform (#/100 ml) 1 26700 1068 Fecal Coliform (#/100 ml) 1 117 14 Trophic State Index:

Comments: Lake Holloway has extensive plant beds of Hydrilla, Southern Naiad and Coontail. Grass Carp were introduced in 1995 and 1997 for Hydrilla control; the dense beds keep the water crystal clear. Recreational activities include fishing and boating.

LAKE HOLLOWAY

TSI

TSI ValueTrend

12/88 12/90 12/92 12/94 12/96 12/98 12/0021

31

41

51

61

71

24

LAKE HORNEY Location: Latitude 28 ° 01 ‘ 59 “ N Longitude 81 ° 56 ‘ 20 “ W Section 20, Township 28 S, Range 24 E Drainage Basin Area: 1084.56 km2 (266.76ac) Lake Surface Area: 28.33 km2 (4.94ac) Mean Depth: 1.2 m (3.9 ft) Lake Volume: 32,429 m3 (85,677,418 gal) Shoreline Length: 677 m (2,221 ft) Predominant Drainage Basin Land Use: Residential 30%, Commercial 15%, Open 55% Historic Low Water Elevation: 135.10 NGVD 1999 Low: 135.3 NGVD 2000 Low: 135.13 NGVD Historic High Water Elevation: 136.73 NGVD 1999 High: 136.73 NGVD 2000 High: 136.13 NGVD Normal Pool: 136.43 NGVD

(Historic High from COL 1999, Historic Low provided from COL 2000)

2000 Water Quality Data: Minimum Maximum Average Total Phosphorus (mg/L) 0.181 1.42 0.645 Total Nitrogen (mg/L) 0.88 8.27 3.33 Chlorophyll-a (µg/L) 32 298 113 Secchi Depth (m) 0.10 0.61 0.37 TSI 62 102 78 Total Coliform (#/100 ml) 100 2000 300 Fecal Coliform (#/100 ml) 40 460 33 Long Term Water Quality Data: 12/88-12/00: Minimum Maximum Average Total Phosphorus (mg/L) 0.001 1.42 0.157 Total Nitrogen (mg/L) 0.20 8.27 1.78 Chlorophyll-a (µg/L) 2 298 35 Secchi Depth (m) 0.10 2.00 0.86 TSI 10 102 63 Total Coliform (#/100 ml) 1 7400 943 Fecal Coliform (#/100 ml) 1 3760 153 Trophic State Index:

Comments: Lake Horney was created from a willow wetland in the 1950’s. It receives inflow from Lake Morton and discharges into Lake Hollingsworth. Grass Carp and herbicides were used to control Hydrilla. Recreational activities include fishing. ✷✷✷✷ Includes the Lake Morton watershed.

LAKE HORNEY

TSI

TSI ValueTrend

12/88 12/90 12/92 12/94 12/96 12/98 12/000

20

40

60

80

100

120

25

LAKE HUNTER Location: Latitude 28 ° 01’ 58” N Longitude 81 ° 57 ‘ 57 ” W Section 24, Township 28 S, Range 23 E Drainage Basin Area: 2962.30 km2 (731.12ac) Lake Surface Area: 376.36 km2 (93.86ac) Mean Depth: 1.7 m (5.5 ft) Lake Volume: 676,151 m3 (178,639,094 gal) Shoreline Length: 2,571 m (8,435 ft) Predominant Drainage Basin Land Use: Residential 51%, Commercial 9%, Open 40% Historic Low Water Elevation: 152.40 NGVD 1999 Low: 160.95 NGVD 2000 Low: 160.78 NGVD Historic High Water Elevation: 163.20 NGVD 1999 High: 163.04 NGVD 2000 High: 162.30 NGVD Normal Pool: 161.00 NGVD

(Historic High: COL, 1994; Historic Low: COL, 1995; Elevation values include readings from December, 1987 to December, 2000) 2000 Water Quality Data: Minimum Maximum Average Total Phosphorus (mg/L) 0.131 0.296 0.215 Total Nitrogen (mg/L) 1.82 3.61 2.86 Chlorophyll-a (µg/L) 41 149 104 Secchi Depth (m) 0.22 0.68 0.36 TSI 71 85 80 Total Coliform (#/100 ml) 10 2500 752 Fecal Coliform (#/100 ml) 5 770 224 Long Term Water Quality Data: 12/88-12/00: Minimum Maximum Average Total Phosphorus (mg/L) 0.019 1.80 0.215 Total Nitrogen (mg/L) 0.51 4.92 2.40 Chlorophyll-a (µg/L) 26 248 81 Secchi Depth (m) 0.18 0.68 0.36 TSI 60 90 77 Total Coliform (#/100 ml) 1 20000 923 Fecal Coliform (#/100 ml) 1 830 84 Trophic State Index:

Comments: Lake Hunter receives inflow from Lakes Wire and Beulah. Grass Carp were introduced to control Hydrilla in the 1980’s. A drawdown was attempted in 1983-1984 for soft sediment consolidation and removal. Extensive shoreline revegetation and control structure modifications were completed in 1992-1993. A new park and boat ramp opened 1997. Recreational activities include fishing and boating and a walking path/bike path that encompasses the lake. ✷✷✷✷ Includes the Lake Beulah and Lake Wire watersheds.

LAKE HUNTER

TSI

TSI ValueTrend

12/88 12/90 12/92 12/94 12/96 12/98 12/0028

38

48

58

68

26

LAKE JOHN Location: Latitude 28° 00 ‘ 15 “ N Longitude 81 ° 56 ‘ 17 “ W Section 32, Township 28 S, Range 24 E Drainage Basin Area: 5564.43 km2 (1373.32ac) Lake Surface Area: 392.55 km2 (96.33ac) Mean Depth: 2.8 m (9.0 ft) Lake Volume: 1,116,123 m3 (294,879,697gal) Shoreline Length: 7,864 m (25,800 ft) Predominant Drainage Basin Land Use: Residential 39%, Commercial 21%, Open 40% Historic Low Water Elevation: 107.28 NGVD 1999 Low: 107.28 NGVD 2000 Low: 107.50 NGVD Historic High Water Elevation: 111.00 NGVD 1999 High: 108.60 NGVD 2000 High: 108.52 NGVD Normal Pool: 108.50 NGVD

(Historic High: COL, 1991; Historic Low: COL, 1999; Elevation values include readings from November, 1987 to December, 2000) 2000 Water Quality Data: Minimum Maximum Average Total Phosphorus (mg/L) 0.182 0.445 0.302 Total Nitrogen (mg/L) 1.07 1.97 1.40 Chlorophyll-a (µg/L) 37 87 53 Secchi Depth (m) 0.40 0.75 0.66 TSI 66 78 70 Total Coliform (#/100 ml) 50 5000 1600 Fecal Coliform (#/100 ml) 5 500 205 Long Term Water Quality Data: 12/88-12/00: Minimum Maximum Average Total Phosphorus (mg/L) 0.129 0.843 0.439 Total Nitrogen (mg/L) 0.20 3.60 1.53 Chlorophyll-a (µg/L) 7 240 48 Secchi Depth (m) 0.10 1.20 0.75 TSI 34 90 68 Total Coliform (#/100 ml) 1 7700 586 Fecal Coliform (#/100 ml) 1 860 47 Trophic State Index:

Comments: Lake John was created during phosphate mining in the 1950's. Grass Carp are used to control Hydrilla. Peterson Park on the southwest shore has facilities for boating, fishing, picnicking. A City owned golf course is located on the north and west shore of the lake.

LAKE JOHN

TSI

TSI ValueTrend

12/88 12/90 12/92 12/94 12/96 12/98 12/0055

65

75

85

95

27

LAKE MIRROR Location: Latitude 28 ° 02 ’ 38 ” N Longitude 81 ° 57 ‘ 06 “ W Section 18, Township 28 S, Range 24 E Drainage Basin Area: 1270.71 km2 (313.69ac) Lake Surface Area: 72.84 km2 (17.29ac) Mean Depth: 2.7 m (9.0 ft) Lake Volume: 197,428 m3 (52,160,477.6 gal) Shoreline Length: 1,052 m (3,453 ft) Predominant Drainage Basin Land Use: Residential 12%, Commercial 63%, Open 25% Historic Low Water Elevation: 177.38 NGVD 1999 Low: 177.58 NGVD 2000 Low: 177.38 NGVD Historic High Water Elevation: 180.01 NGVD 1999 High: 178.66 NGVD 2000 High: 178.42 NGVD Normal Pool: 178.30 NGVD

(Historic High: COL, 1988; Historic Low: COL, 2000; Elevation values include readings from December, 1988 to December, 2000) 2000 Water Quality Data: Minimum Maximum Average Total Phosphorus (mg/L) 0.130 0.235 0.166 Total Nitrogen (mg/L) 0.87 2.01 1.26 Chlorophyll-a (µg/L) 26 32 30 Secchi Depth (m) 0.51 0.85 0.67 TSI 61 71 65 Total Coliform (#/100 ml) 200 1200 625 Fecal Coliform (#/100 ml) 40 130 98 Long Term Water Quality Data: 12/88-12/00: Minimum Maximum Average Total Phosphorus (mg/L) 0.02 0.423 0.131 Total Nitrogen (mg/L) 0.70 4.05 1.81 Chlorophyll-a (µg/L) 2 133 42 Secchi Depth (m) 0.20 1.70 0.74 TSI 45 83 69 Total Coliform (#/100 ml) 30 5200 787 Fecal Coliform (#/100 ml) 1 944 112 Trophic State Index:

Comments: Lake Mirror discharges to Lake Parker through a piped conveyance. Spatterdock or Yellow Cowlily was planted in 1989 to replace the undesirable plants that infested the shoreline. An amphitheater was constructed in 1999 on the south side of the lake and Hollis Gardens is to be constructed by summer of 2000. A concrete capped structure protrudes into the lake from the north shore. This structure served to separate the inflow and discharge waters at the City's old power plant that preceded the Larsen and McIntosh plants. Recreational activities include a walking path. No fishing or boating is allowed in Lake Mirror.

LAKE MIRROR

TSI

TSI ValueTrend

12/88 12/90 12/92 12/94 12/96 12/98 12/0055

65

75

85

95

28

LAKE MORTON Location: Latitude 28 ° 02 ‘ 17 “ N Longitude 81 ° 57 ‘ 11 “ W Section 19, Township 28 S, Range 24 E Drainage Basin Area: 870.07 km2 (214.89ac) Lake Surface Area: 161.87 km2 (39.52ac) Mean Depth: 3.6 m (11.8 ft) Lake Volume: 576,331 m3 (152,266,650 gal) Shoreline Length: 1,463 m (4,800 ft) Predominant Drainage Basin Land Use: Residential 35% , Commercial 33%, Open 32% Historic Low Water Elevation: 176.73 NGVD 1999 Low: 177.35 NGVD 2000 Low: 176.84 NGVD Historic High Water Elevation: 180.47 NGVD 1999 High: 179.25 NGVD 2000 High: 178.14 NGVD Normal Pool: 178.25 NGVD


Comments: Lake Morton is located in the heart of downtown Lakeland and is a designated bird sanctuary; boating and hook and line fishing are prohibited due to the presence of large numbers of domestic waterfowl. The presence and feeding of waterfowl can constitute a significant source of nutrient and bacteria loading to lakes. The lakeshore is the site of several outdoor events throughout the year. Lake Morton discharges to Lake Horney and Hollingsworth. Recreational activities include picnicking and walking.

LAKE MORTON

TSI

TSI ValueTrend

12/88 12/90 12/92 12/94 12/96 12/98 12/0055

65

75

85

95

29

LAKE PARKER Location: Latitude 28 ° 04 ‘ 04 “ N Longitude 81 ° 55 ‘ 53 “ W Section 08, Township 28 S, Range 24 E Drainage Basin Area: 55357.00 km2 (13673.92ac) Lake Surface Area: 8834.30 km2 (2181.01ac) Mean Depth: 1.6 m (5.3 ft) Lake Volume: 15,080,974 m3 (3,984,393,331gal) Shoreline Length: 27,379 m (89,827 ft) Predominant Drainage Basin Land Use: Residential 16%, Commercial 8%, Open 76% Historic Low Water Elevation: 127.02 NGVD 1999 Low: 129.30 NGVD 2000 Low: 127.66 NGVD Historic High Water Elevation: 131.89 NGVD 1999 High: 130.90 NGVD 2000 High: 129.85 NGVD Normal Pool: 130.30 NGVD

(Historic High: SWFWMD 1982; Historic Low: SWFWMD, 1986; Elevation values include readings from May, 1949 to December, 2000) 2000 Water Quality Data: Minimum Maximum Average Total Phosphorus (mg/L) 0.210 3.79 1.18 Total Nitrogen (mg/L) 3.12 4.81 4.20 Chlorophyll-a (µg/L) 114 175 135 Secchi Depth (m) 0.22 0.37 0.28 TSI 84 89 87 Total Coliform (#/100 ml) 50 6000 1550 Fecal Coliform (#/100 ml) 5 680 195 Long Term Water Quality Data: 12/88-12/00: Minimum Maximum Average Total Phosphorus (mg/L) 0.25 3.790 0.243 Total Nitrogen (mg/L) 0.60 11.40 3.10 Chlorophyll-a (µg/L) 19 223 82 Secchi Depth (m) 0.19 0.82 0.37 TSI 59 95 78 Total Coliform (#/100 ml) 1 7000 495 Fecal Coliform (#/100 ml) 1 4000 165 Trophic State Index:

Comments: Lake Parker is the largest lake in the City of Lakeland; phosphate was mined along the north shore of the lake. Lake Parker receives water from Lakes Mirror, Crago, Bonny, & Garden; outflows to Saddle Creek, and the Peace River; the lake has 3 parks, 3 public boat ramps and 2 fishing piers; herbicides are used to control Hydrilla. ✷✷✷✷ Includes known contributing upstream drainage basins. Recreational activities include fishing and boating, picnic areas and a walking path.

LAKE PARKER

TSI

TSI ValueTrend

12/88 12/90 12/92 12/94 12/96 12/98 12/0067

72

77

82

87

92

97

30

LAKE SOMERSET Location: Latitude 28 ° 00 ‘ 14 “ N Longitude 81 ° 55 ‘ 52 ” W Section 32, Township 28 S, Range 24 E Drainage Basin Area: 11019.60 km2 (2721.94ac) Lake Surface Area: 194.25 km2 (46.93ac) Mean Depth: 2.4 m (7.9 ft) Lake Volume: 468,811 m3 (123,859,866 gal) Shoreline Length: 3,911 m (12,831 ft) Predominant Drainage Basin Land Use: Residential 38%, Commercial 11%, Open 51% Historic Low Water Elevation: 107.28 NGVD 1999 Low: 107.28 NGVD 2000 Low: 107.50 NGVD Historic High Water Elevation: 111.00 NGVD 1999 High: 108.60 NGVD 2000 High: 108.52 NGVD Normal Pool: 108.50 NGVD


Comments: Lake Somerset was created during phosphate mining. The lake is connected to Lake John by a culvert under New Jersey Road. Lake Somerset receives water from Lake Bentley and discharges via Stahl Canal to Banana Lake, Lake Hancock and the Peace River. There is a public boat ramp. Recreational activities include fishing and boating. ✷✷✷✷ Includes Bentley and John watersheds.

LAKE SOMERSET

TSI

TSI ValueTrend

12/88 12/90 12/92 12/94 12/96 12/98 12/0043

53

63

73

83

93

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LAKE WIRE Location: Latitude 28 ° 02 ‘ 48 “ N Longitude 81 ° 57’ 38 “ W Section 13, Township 28 S, Range 23 E Drainage Basin Area: 433.01 km2 (106.21ac) Lake Surface Area: 89.03 km2 (21.98ac) Mean Depth: 3.3 m (10.6 ft) Lake Volume: 303,289 m3 (80,128,953 gal) Shoreline Length: 1,151 m (3,776 ft) Predominant Drainage Basin Land Use: Residential 32%, Commercial 36%, Open 32% Historic Low Water Elevation: 192.28 NGVD 1999 Low: 193.67 NGVD 2000 Low: 192.28 NGVD Historic High Water Elevation: 198.22 NGVD 1999 High: 196.25 NGVD 2000 High: 195.31 NGVD Normal Pool: 195.00 NGVD

(Historic High: USGS, 1959; Historic Low: COL, 2000; Elevation values include readings from November, 1987 to December, 2000) 2000 Water Quality Data: Minimum Maximum Average Total Phosphorus (mg/L) 0.092 0.154 0.131 Total Nitrogen (mg/L) 0.483 0.782 0.640 Chlorophyll-a (µg/L) 4 10 6 Secchi Depth (m) 2.95 3.75 3.38 TSI 39 50 45 Total Coliform (#/100 ml) 50 100 73 Fecal Coliform (#/100 ml) 5 24 11 Long Term Water Quality Data: 12/88-12/00: Minimum Maximum Average Total Phosphorus (mg/L) 0.004 9.05 0.292 Total Nitrogen (mg/L) 0.48 3.38 0.953 Chlorophyll-a (µg/L) 0.40 21 6 Secchi Depth (m) 1.20 5.00 3.3 TSI 21 62 45 Total Coliform (#/100 ml) 1 13000 572 Fecal Coliform (#/100 ml) 1 910 56 Trophic State Index:

Comments: Lake Wire outflows to Lake Hunter. Grass Carp and mechanical harvesting are used to control Hydrilla. Hydrilla beds keep water clear and attract migratory waterfowl in winter. Assessment and remediation of past metal contamination is ongoing. Recreational activities include fishing and a walking path around the lake.

LAKE WIRE

TSI

TSI ValueTrend

12/88 12/90 12/92 12/94 12/96 12/98 12/0028

38

48

58

68

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Table 2. Average annual Water Quality Data for City of Lakeland Lakes during 2000. LAKE TSI

(AVG) SECCHI

(M) TN

(MG/L) TP

(MG/L) CHLa (µµµµG/L)

T_Coli (# Col /100 ml)

F_Coli (# Col /100 ml)

BENTLEY 71 0.52 1.49 0.360 58 140 15 BEULAH 60 1.24 1.00 0.16 30.2 118 39 BONNET 77 0.44 2.48 0.245 70 163 33 BONNY 86 0.27 4.41 0.439 105 188 96 CRAGO 74 0.70 1.96 0.258 55 191 60 GIBSON 47 1.16 0.765 0.268 6 14 3 HOLLINGSWORTH 86 0.33 3.37 0.449 140 775 420 HOLLOWAY 47 2.68 0.738 0.147 6 64 4 HORNEY 78 0.37 3.33 0.645 113 300 33 HUNTER 80 0.36 2.86 0.215 104 752 224 JOHN 70 0.66 1.40 0.302 53 1600 205 MIRROR 65 0.67 1.26 0.166 30 625 98 MORTON 70 0.59 1.49 0.208 49 575 130 PARKER 87 0.28 4.2 1.18 135 1550 195 SOMERSET 74 0.53 1.43 0.253 87 39 6 WIRE 45 3.38 0.640 0.131 6 73 11 Table 3. Average annual Water Quality Data for City of Lakeland Lakes from 12/88 to 12/00. LAKE TSI

(AVG) SECCHI

(M) TN

(MG/L) TP

(MG/L) CHLa (µµµµG/L)

T_Coli (# Col /100 ml)

F_Coli (# Col /100 ml)

BENTLEY 75 0.46 2.47 0.262 63 1083 41 BEULAH 60 1.60 1.50 0.101 24.7 7864 40 BONNET 84 0.31 4.66 0.540 182 582 59 BONNY 73 0.49 2.76 0.215 76 624 42 CRAGO 75 0.66 2.18 0.270 63 130 11 GIBSON 54 0.98 1.18 0.268 13 155 8 HOLLINGSWORTH 85 0.29 4.07 0.251 164 1469 516 HOLLOWAY 47 2.34 1.20 0.071 7 1068 14 HORNEY 63 0.86 1.78 0.157 35 943 153 HUNTER 77 0.36 2.40 0.215 81 923 84 JOHN 68 0.75 1.53 0.439 48 586 47 MIRROR 69 0.74 1.81 0.131 42 787 112 MORTON 77 0.43 3.18 0.155 77 1027 214 PARKER 78 0.37 3.1 0.243 82 495 165 SOMERSET 71 0.68 1.77 0.316 56 949 55 WIRE 45 3.30 0.953 0.292 6 572 56

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Table 4. Average Metal Concentrations for City of Lakeland Lakes - 2000. LAKE Ca

(MG/L) Mg

(MG/L) Fe

(µµµµG/L) Zn

(µµµµG/L) Cr

(µµµµG/L) Pb

(µµµµG/L) Cd

(µµµµG/L) Al

(µµµµG/L) BENTLEY 23 4 106 12 0.52 3.2 0.28 301 BEULAH 26 2 69 15 0.35 1.31 0.09 109 BONNET 16 3 115 18 1.18 4.9 0.18 445 BONNY 18 2 132 24 0.68 3.8 0.18 342 CRAGO 17 4 53 15 0.40 2.3 0.40 176 GIBSON 6 4 177 15 0.53 1.15 0.10 223 HOLLINGSWORTH 15 3 220 14 0.90 8.2 0.10 871 HOLLOWAY 19 3 51 13 0.30 0.6 0.10 108 HORNEY 23 4 259 22 1.0 4.8 0.10 534 HUNTER 22 2 241 20 0.50 3.1 0.10 432 JOHN 23 4 156 17 0.30 1.3 0.10 192 MIRROR 25 2 59 14 0.30 1.5 0.10 107 MORTON 23 7 49 14 0.70 2.3 0.10 144 PARKER 26 4 149 21 0.70 4.8 0.10 654 SOMERSET 25 4 110 12 0.50 3.5 0.30 255 WIRE 19 1 69 15 0.40 9.0 0.30 98 (Ca-Calcium, Mg-Magnesium, Fe-Iron, Zn-Zinc, Cr-Cromium, Pb-Lead, Cd-Cadmium, Al-Aluminum) Table 5. Average Metal Concentrations for Lakeland Lakes from 12/88 to 12/00. LAKE Ca

(MG/L) Mg

(MG/L) Fe

(µµµµG/L) Zn

(µµµµG/L) Cr

(µµµµG/L) Pb

(µµµµG/L) Cd

(µµµµG/L) Al

(µµµµG/L) BENTLEY 21 4 162 17 0.91 1.66 0.29 302 BEULAH 19 2 80 18 0.62 1.10 0.27 114 BONNET 17 3 168 26 1.73 4.72 0.32 523 BONNY 18 2 76 18 0.65 2.32 0.26 167 CRAGO 13 4 57 14 0.90 1.40 0.30 192 GIBSON 11 3 139 18 0.74 0.89 0.21 204 HOLLINGSWORTH 18 3 188 16 0.80 8.00 0.30 472 HOLLOWAY 21 2 41 17 0.50 0.90 0.30 115 HORNEY 22 4 122 25 0.80 3.00 0.30 303 HUNTER 24 2 196 18 0.80 3.50 0.20 441 JOHN 23 4 161 16 0.70 1.10 0.20 253 MIRROR 24 3 99 26 0.70 2.10 0.20 167 MORTON 26 5 77 14 0.40 1.70 0.20 129 PARKER 23 4 149 24 1.3 5.00 0.20 512 SOMERSET 23 4 152 18 0.80 1.10 0.30 222 WIRE 20 1 70 25 1.3 7.10 0.20 116 (Ca-Calcium, Mg-Magnesium, Fe-Iron, Zn-Zinc, Cr-Cromium, Pb-Lead, Cd-Cadmium, Al-Aluminum) *Acceptable standards for metals are calculated on a per sample basis using hardness.

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Table 6. List of Lakeland's 38 named lakes.

LAKE ACREAGE ORIGIN LATITUDE LONGITUDE BENTLEY 52 MAN-MADE 28 ° 00 ′ 51 ″ N 81 ° 55 ′ 35 ″ W BEULAH 17 NATURAL 28 ° 02 ′ 26 ″ N 81 ° 58 ′ 06 ″ W BLANTON 2 MAN-MADE 28 ° 02 ′ 34 ″ N 82 ° 00 ′ 07 ″ W BONNET 79 NATURAL 28 ° 02 ′ 53 ″ N 81 ° 58 ′ 36 ″ W BONNY 345 NATURAL 28 ° 02 ′ 21 ″ N 81 ° 55 ′ 38 ″ W BONNY (LITTLE) 26 NATURAL 28 ° 01 ′ 50 ″ N 81 ° 55 ′ 17 ″ W CANYON 9 MAN-MADE 27 ° 59 ′ 33 ″ N 81 ° 56 ′ 36 ″ W CHARLES 7 MAN-MADE 28 ° 02 ′ 43 ″ N 82 ° 00 ′ 18 ″ W CRAGO 52 MAN-MADE 28 ° 05 ′ 34 ″ N 81 ° 56 ′ 52 ″ W ERNEST 5 MAN-MADE 28 ° 02 ′ 57 ″ N 82 ° 00 ′ 25 ″ W FISH 59 NATURAL 28 ° 05 ′ 09 ″ N 81 ° 55 ′ 13 ″ W GEORGE 9 MAN-MADE 28 ° 03 ′ 03 ″ N 82 ° 00 ′ 19 ″ W GIBSON 490 NATURAL 28 ° 06 ′ 31 ″ N 81 ° 57 ′ 33 ″ W GLEN 7 MAN-MADE 28 ° 02 ′ 45 ″ N 82 ° 00 ′ 35 ″ W HOLLINGSWORTH 355 NATURAL 28 ° 01 ′ 32 ″ N 81 ° 56 ′ 44 ″ W HOLLOWAY 24 NATURAL 28 ° 02 ′ 04 ″ N 81 ° 55 ′ 01 ″ W HORNEY ✦ 7 MAN-MADE 28 ° 01 ′ 59 ″ N 81 ° 56 ′ 20 ″ W HOWARD 6 MAN-MADE 28 ° 03 ′ 03 ″ N 81 ° 59 ′ 59 ″ W HUNTER 93 NATURAL 28 ° 01 ′ 58 ″ N 81 ° 57 ′ 57 ″ W JIM 5 MAN-MADE 28 ° 02 ′ 51 ″ N 82 ° 00 ′ 21 ″ W JOHN 97 MAN-MADE 28 ° 00 ′ 15 ″ N 81 ° 56 ′ 17 ″ W KELLY 7 MAN-MADE 27 ° 59 ′ 50 ″ N 81 ° 57 ′ 48 ″ W LARCH 8 NATURAL 28 ° 06 ′ 04 ″ N 81 ° 56 ′ 17 ″ W MACK 2 MAN-MADE 28 ° 02 ′ 49 ″ N 82 ° 00 ′ 52 ″ W MEADOW VIEW LAKE 51 NATURAL 28 ° 05 ′ 52 ″ N 81 ° 59 ′ 05 ″ W MERIDIAN 5 MAN-MADE 27 ° 59 ′ 13 ″ N 81 ° 55 ′ 24 ″ W MIRIAM 31 MAN-MADE 27 ° 58 ′ 44 ″ N 81 ° 57 ′ 16 ″ W MIRROR 18 NATURAL 28 ° 02 ′ 38 ″ N 81 ° 57 ′ 06 ″ W MORTON 40 NATURAL 28 ° 02 ′ 17 ″ N 81 ° 57 ′ 11 ″ W PARKER 2183 NATURAL 28 ° 04 ′ 04 ″ N 81 ° 55 ′ 53 ″ W POLLOCK 20 MAN-MADE 27 ° 59 ′ 06 ″ N 81 ° 55 ′ 35 ″ W SAN GULLY 3 MAN-MADE 28 ° 00 ′ 42 ″ N 81 ° 58 ′ 55 ″ W SHERWOOD FOREST 79 NATURAL 28 ° 08 ′ 18 ″ N 81 ° 54 ′ 51 ″ W SOMERSET 48 MAN-MADE 28 ° 00 ′ 14 ″ N 81 ° 55 ′ 52 ″ W WATERVIEW 5 MAN-MADE 27 ° 59 ′ 16 ″ N 81 ° 55 ′ 39 ″ W WATKINS 2 NATURAL 28 ° 01 ′ 16 ″ N 81 ° 55 ′ 52 ″ W WIRE 22 NATURAL 28 ° 02 ′ 48 ″ N 81 ° 57 ′ 38 ″ W WOOD 6 MAN-MADE 27 ° 59 ′ 53 ″ N 81 ° 55 ′ 55 ″ W ✦ Lake Horney was a natural willow wetland dredged in the mid-fifties to create a lake.

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GLOSSARY

AQUIFER: An underground zone of porous rock and sediment which can hold water. The surficial aquifer, closest to land surface, is made up mostly of sand. Beneath the clay confining unit lies the Floridan aquifer system, composed mostly of limestone. This is the primary source of drinking water for southwest Florida. BATHYMETRIC MAP: A map which shows the bottom contour of the lake in feet or meters. BENTHIC MACROINVERTEBRATES: Organisms that live in or on the bottom or other substrate in an aquatic environment that can be seen with an unaided eye. CHLOROPHYLL a: A green pigment found in algae and higher plants (which enables them to utilize energy from the sun) essential for the conversion of light energy to chemical energy. Chlorophyll a in a water sample is a useful indicator of phytoplankton biomass. COLIFORM BACTERIA: A group of non-pathogenic bacteria that live in the digestive tracts of warm blooded animals. t_col = Total Coliform which is a group of bacteria known to flourish outside the intestinal tract of animals. f_col= Fecal Coliform which is a group of heat tolerant bacteria that exclusively originates in the intestines of warm blooded animals. COMMERCIAL DEVELOPMENT: In this report, a land use term which includes commercial and institutional development. CONDENSATION: The process of water vapor cooling and changing to a liquid as tiny droplets, forming clouds or fog. CONTAMINANTS: Impurities, pollutants, pathogens or debris that makes water unhealthy for living. CULTURAL EUTROPHICATION: The process in which lake aging is greatly accelerated by increased inputs of nutrients and sediments to a lake as a result of watershed disturbance by man. DRAINAGE BASIN AREA: The area of land enclosed by a topographic divide in which direct surface runoff from precipitation normally drains by gravity into a lake or Waterbury. These areas include all closed basins and non-contributing areas. DRAINAGE BASIN: Refers to the hydrologic watershed within which a lake lies. ECOSYSTEM: A system formed by the interaction of a community of organisms with their environment. ENRICHMENT: The buildup or accumulation of nutrients in concentrations that promote excessive algae or plant growth. ESTUARY: A coastal area where a river meets the ocean. EUTROPHIC: From the Greek word for “well-nourished”, describes a lake with high plant productivity and low water clarity. EUTROPHICATION: A natural process which results from the gradual accumulation of nutrients, increased productivity, and a slow filling in of the basin with accumulated sediments, silt, and organic matter from the watershed. The process of physical, chemical and biological changes associated with nutrient, organic matter, and silt enrichment and sedimentation of a lake or reservoir. EVAPORATION: A process by which heated water changes from a liquid to a vapor.

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EXOTICS: Plants or animals that are not native to Florida; these plants have been brought in from other countries or continents. Without natural enemies to control population growth these plants or animals tend to grow unchecked and become problems. GRASS CARP: Exotic fish species from Asia introduced in the U.S. as a biological control method. Grass carp is essentially a herbivore (plant eater) and is primarily to control Hydrilla in lakes throughout Florida. GROUNDWATER: Water that is underground in the aquifers. HARDNESS: The quality of impure water that is imparted by the presence of dissolved salts, esp. calcium sulfate or bicarbonate. HYDRAULIC RESIDENCE TIME: The time required for the lakes volume to replace itself. HYDRILLA: An invasive exotic plant introduced to the U.S. by the aquarium industry. Hydrilla grows as a submersed aquatic plant, which forms dense floating mats that impede boat traffic. LIMNOLOGY: The science of rivers and lakes. MESOTROPHIC: Refers to a lake with intermediate nutrient availability and biological productivity. NUTRIENTS: Elements or chemicals essential to life including carbon, oxygen, nitrogen, phosphorus, and others. OLIGOTROPHIC: Greek word meaning poorly nourished. Oligotrophic describes a lake with low plant productivity and high water clarity. OPEN AREA: A land use term used to describe agricultural, water and undeveloped land. PERCOLATION: Downward seepage of surface water through the ground, recharging the groundwater within the aquifer systems. PHOTOSYNTHESIS: The chemical process by which chlorophyll containing plants use light to convert carbon dioxide and water into carbohydrates releasing oxygen as a by-product. PHYTOPLANKTON: microscopic free-floating plants found in aquatic systems. PRODUCTIVITY: The rate of formation of organic matter (living) by biological process over a defined period of time. RESIDENTIAL DEVELOPMENT: In this report, a land use term used to describe high and low density residential development. RUNOFF: Excess rainwater which flows over the land surface into water bodies, carrying both nutrients and pollutants. SECCHI DISC: A black and white disk, 20 cm in diameter, used to measure water clarity. SINKHOLE: A land surface feature that usually develops during times of low groundwater levels: occurs when the weight of sediments above an empty cavern causes the cavern’s ceiling to collapse, creating a depression in the land or a hole in the bottom of a lake or other surface waterbody. SOLUBLE: A substance that is capable of being dissolved or liquefied. SPRING: Water flowing upward to the land surface from an underground aquifer.

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STORMWTAER RUNOFF: The water flowing over the land during and immediately after a heavy rainfall that is unusually full of pollutants, sediments, and nutrients. TN: Total Nitrogen. TP: Total Phosphorus. TRANSPIRATION: A process by which water vapor is released to the air from plants. When combined with evaporation, it creates evapotranspiration. TROPHIC STATE INDEX: (T.S.I) A numeric value condensed from several individual water quality parameters used to assess water quality; this is a tool used by lake managers to describe one aspect water quality- richness or productivity. TROPHY: Refers to the rate of organic matter supplied by or to the lake per unit of time; it is then an expression of the combined effects of organic matter supplied to the lake. WETLANDS: An area where water covers the ground for more than a month a year.

CITY OF LAKELAND - University of South Florida...Lakeland Lakes Program during its first ten years...

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