Water Quality

Florida’s future depends on a continued supply of adequate clean fresh waterWater that is relatively free of salts.. Water quality and water quantity are both important: it does little good to have vast amounts of polluted water. Plants, fish and other animals, as well as humans, all require adequate amounts of clean water.

The quantity of water changed by human activity is far greater than the amount of water directly used by humans (Betz 1984). Each time humans withdraw ground water or surface water for a particular purpose, waste is generated. Household use generates wastewaterUsed domestic water for disposal, from baths, showers, toilets, washing machines and the like from toilets, sinks, showers, bathtubs, dishwashers and washing machines; phosphate mining generates phosphate slime; manufacturing generates chemical waste; irrigation generates runoffThe topographic flow of water from precipitation to stream channels located at lower elevations. Occurs when the infiltration capacity of an area's soil has been exceeded. It also refers to the water leaving an area of drainage. Also called overland flow. containing nutrientsAny food, chemical element or compound an organism requires to live, grow, or reproduce. from fertilizers, as well as from pesticidesA chemical that kills, controls, drives away, or modifies the behavior of pests. and herbicides. Even rain contains impurities generated by burning of fossil fuelsCarbon based remains of organic matter that has been geologically transformed into coal, oil and natural gas. Combustion of these substances releases large amounts of energy. Currently, humans are using fossil fuels to supply much of their energy needs., dust and ash. It’s not enough to be careful about the amount of water we use. We must also do our best to return it to the environment as pure as possible.

Water Supply

Some places in Florida, such as the Florida Keys and St. Petersburg, never had enough fresh waterWater that is relatively free of salts. to support large-scale development. Each day, 16 million gallons of water flow from wells near Homestead, on the mainland of Florida, to the Florida Keys. Water travels through a 130-mile-long pipeline supplying water all the way to Key West. St. Petersburg, “a peninsula on a peninsula” with the highest population density in Florida (3,100 persons per square mile), ran out of water in the 1920s and now relies on well fields in Hillsborough and Pasco counties. In other places, water use is rapidly surpassing inexpensive water supply.

“Although water is part of a global system, how it is used and managed locally and regionally is what really counts. Unlike oil, wheat and most other important commodities, water is needed in quantities too large to make it practical to transport long distances.”
Sandra Postel, Last Oasis, 1992, p. 23

Fast-growing Charlotte County gets water from DeSoto County, and Sarasota County gets water from wells in Manatee County. Other parts of Florida are also experiencing shortages. Water levels in the Floridan aquifer in coastal Walton, Okaloosa and Santa Rosa counties in the Panhandle have dropped as much as 100 feet below sea level. Near Orlando, groundwaterWater in the ground. Water that occupies the pore spaces found in some types of bedrock. levels have dropped 25 feet in places, and the flow in springs in the Wekiva River basin has diminished. Titusville on the east coast has notified the St. Johns River Water Management District that by 2010 it will not have enough water to meet the needs of projected growth.

Water resource caution areas, (also referred to as water use caution areas), places where water is either scarce or contaminated, now cover thousands of square miles throughout the state. The most extensive water resource caution areas are in southwest Florida in all or parts of Pasco,Pinellas, Hillsborough, Sarasota, Charlotte, DeSoto, Polk and Highlands counties. Florida’s water management districts are committed to finding new ways of meeting the demand for water. Providing high-quality drinking water is expensive, and using that water to meet all water needs is unnecessary.

Alternative sources of supplies

Floridians will increasingly use alternative supplies of water to meet nonpotable demands, instead of seeking new, often faraway and more pristine sources. Reclaimed water, for example, can be used to irrigate golf courses and landscaping, as well as in industrial processes and power generation. The use of desalination, particularly of brackish ground water, is increasing in Florida’s populated areas. Another way to increase water supply is conservation and increased efficiency. Household fixtures, such as toilets and showers, that save water are now available. Landscaping with native, drought-tolerant plants (Xeriscaping) also helps conserve water. Agriculture and industry have begun to implement new and more efficient ways of using water. Water management districts have begun to explore the option of storing water in aquifers during times of abundant rainfall and withdrawing it during times when rainfall is scarce, a process known as aquifer storage and recovery.

Water quality

Good quality water in adequate amounts is indispensable for the water we drink, but it is also essential for many other uses. We cannot safely swim or fish in polluted waters nor can Florida’s natural systems survive without adequate water of good quality. The recreational and ecological values of good quality water and other natural resources are frequently acknowledged but are rarely considered in management decisions because we don’t buy and sell them as we do other commodities. An article published in 1997 (Costanza et al.) in the journal Nature summarizes and synthesizes studies aimed at estimating the value of ecological functions and services. The authors conclude that the economic value of Earth’s natural systems averages $33 trillion per year, which is 1.2 times as much economic value created by humans and measured by the combined gross national product of all the countries in the world.

Scientists use a number of tests and measures to help them determine water quality. These include turbidity, nutrient levels, pHp(otential of) H(ydrogen); Scale used to measure the alkalinity or acidity of a substance through the determination of the concentration of hydrogen ions in solution. A pH of 7.0 is neutral. Values below 7.0, to a minimum of 0.0, indicate increasing acidity. Values above 7.0, to a maximum of 14.0, indicate increasing alkalinity., dissolved oxygenMeasures the amount of gaseous oxygen dissolved in an aqueous solution. Oxygen gets into water by diffusion from the surrounding air, by aeration (rapid movement), and as a waste product of photosynthesis., conductivity and temperature.

Turbidity is characterized by a cloudy or muddy appearance caused by suspended solids that decrease the ability of the sunlight to penetrate the water. The most common suspended solids are soil particles and algae. Water may sometimes be naturally turbid because of high amounts of organic

1. Relating to an organism.
2. Derived from an organism.

NutrientsAny food, chemical element or compound an organism requires to live, grow, or reproduce. in the proper amount are necessary for healthy aquatic systems, but in excess, nutrientsAny food, chemical element or compound an organism requires to live, grow, or reproduce., primarily nitrogen and phosphorus, can be harmful. Nutrients come from runoff containing fertilizer, waste from leaking septic tanks, decaying lawn debris and animal wastes. When too many nutrients are present, certain plants grow explosively and crowd out other plants, creating a monoculture. Increases in nutrients may result in algal blooms in lakes and rivers. When algae multiplies rapidly, it uses up dissolved oxygen, leaving less available for other forms of aquatic life. Excess nutrients also frequently increase nonnative nuisance plants, such as water hyacinth and hydrilla.

pH (potential of hydrogen) is the measure of the amount of hydrogen ions (H+) and hydroxide ions (OH-) in a solution. The more acidicHaving the properties of an acid, or containing acid; having a pH below 7.0 a solution, the greater the amount of hydrogen ions. The more basic or alkalineContaining an alkali or having the properties of an alkali; having a pH greater than 7.0 the solution, the greater the amount of hydroxide ions. The pH scale ranges from 0 to 14. The lower the pH, the more acidic the solution is; the higher the pH, the more basic the solution is. A solution with a pH of 7 is neutral, neither basic nor acidic. Pure water has a pH of 7. Orange juice has a pH of 4 and battery acid has a pH of 0.5. Milk of Magnesia has a pH of 10 and lye has a pH of 14. Most aquatic organismsAny form of life. prefer water with a pH ranging from 6.5 to 8.5. As acidity rises (pH falls), other compoundA compound is the atoms of different elements joined together. in contact with the water or the soil may release toxicPoisonous, a substance that reacts with specific cellular components to kill cells. elementsA molecule composed of one type of atom. Chemists have recognized or created 112 different types of elements. Two or more different elements form a compound. (for example, aluminum and mercurya heavy, silver-white, metallic element, the only metal that is liquid at room temperature; also called quicksilver. A virulent poison, dangerous to handle and work with.). Storm waterWater that results from a storm; can cause flooding and contamination of sewers. runoffThe topographic flow of water from precipitation to stream channels located at lower elevations. Occurs when the infiltration capacity of an area's soil has been exceeded. It also refers to the water leaving an area of drainage. Also called overland flow. containing leakage from faulty sewer lines or septic tanks, runoff from agricultural areas and acid rainRain (and snow, fog, dust particles, etc.) containing acids that form in the atmosphere when sulfur dioxides and nitrogen oxides from industrial emissions and automobile exhaust combine with water. can all decrease pH in lakes, rivers and estuariesThe wide lower course of a river where the tide flows in, causing fresh and salt water to mix., threatening aquatic organisms and releasing potentially harmful elementsA molecule composed of one type of atom. Chemists have recognized or created 112 different types of elements. Two or more different elements form a compound..

dissolved oxygenMeasures the amount of gaseous oxygen dissolved in an aqueous solution. Oxygen gets into water by diffusion from the surrounding air, by aeration (rapid movement), and as a waste product of photosynthesis. in water is essential for the survival of nearly all aquatic plants and animals. It is especially vital to a healthy population of microbes, which control amounts of phosphorus in the water and the formation of biofilmA complex aggregation of microorganisms marked by the excretion of a protective and adhesive matrix. Biofilms are also often characterized by surface attachment to which certain algae attach. Aquatic organisms, including most fish, generally thrive when dissolved oxygen levels are 5 parts per million (ppm) or greater. Oxygen in the water comes from the air and as a byproduct of photosynthesisIs the chemical process where plants and some bacteria can capture and organically fix the energy of the sun. This chemical reaction can be described by the following simple equation:
6CO₂ + 6H₂O + light energy >>> C₆H₁₂O₆ + 6O₂
The main product of photosynthesis is a carbohydrate, such as the sugar glucose, and oxygen which is released to the atmosphere. All of the sugar produced in the photosynthetic cells of plants and other organisms is derived from the initial chemical combining of carbon dioxide and water with sunlight. This chemical reaction is catalyzed by chlorophyll acting in concert with other pigment, lipid, sugars, protein, and nucleic acid molecules. Sugars created in photosynthesis can be later converted by the plant to starch for storage, or it can be combined with other sugar molecules to form specialized carbohydrates such as cellulose, or it can be combined with other nutrients such as nitrogen, phosphorus, and sulfur, to build complex molecules such as proteins and nucleic acids. Also see chemosynthesis. It is said that photosynthesis gives rise to three quarters of the world supply of oxygen that we breathe.. The cooler the water, the more dissolved oxygen it will hold. However, at night when photosynthesisIs the chemical process where plants and some bacteria can capture and organically fix the energy of the sun. This chemical reaction can be described by the following simple equation:
6CO₂ + 6H₂O + light energy >>> C₆H₁₂O₆ + 6O₂
The main product of photosynthesis is a carbohydrate, such as the sugar glucose, and oxygen which is released to the atmosphere. All of the sugar produced in the photosynthetic cells of plants and other organisms is derived from the initial chemical combining of carbon dioxide and water with sunlight. This chemical reaction is catalyzed by chlorophyll acting in concert with other pigment, lipid, sugars, protein, and nucleic acid molecules. Sugars created in photosynthesis can be later converted by the plant to starch for storage, or it can be combined with other sugar molecules to form specialized carbohydrates such as cellulose, or it can be combined with other nutrients such as nitrogen, phosphorus, and sulfur, to build complex molecules such as proteins and nucleic acids. Also see chemosynthesis. It is said that photosynthesis gives rise to three quarters of the world supply of oxygen that we breathe. stops, animals continue to use oxygen and the dissolved oxygen content of water drops.

Conductivity refers to how well the water conducts or transmits an electrical current. Pure distilled water does not conduct a current. As the concentration of mineralsComponent of rocks. A naturally occurring inorganic solid with a crystalline structure and a specific chemical composition. Over 2,000 types of minerals have been classified. and salts in the water increases, however, conductivity rises. Conductivity is therefore an indirect measure of the mineral content of water. Sediments from storm water runoff and intrusion of seawater increase the mineral content of water. Increases in conductivity may indicate water quality problems from increased salinityConcentration of dissolved salts found in a sample of water. Measured as the total amount of dissolved salts in parts per thousand. Seawater has an average salinity of about 34 parts per thousand (ppt), alternatively, measured as Specific Conductance or Specific Conductivity expressed in microSiemens per centimeter (µS/cm) normalized to a temperature of 25 degrees Celsius. Pure water is reckoned to be 0 µS/cm, and ocean seawater at 50,000 µS/cm. or increased sediment. Both of these make water less useful to humans and to natural systems.

Temperature affects the growth and life cycles of many aquatic organisms. Nearly all organisms have a temperature range they prefer or even require. Sediments can absorb heat and increase water temperature. Storm waterWater that results from a storm; can cause flooding and contamination of sewers. runoff from heated imperviousNot allowing fluid to pass through surfaces and power plant outfalls also increases water temperature. As water temperature increases, the life cycles of aquatic insects may accelerate. The growth of algae generally increases, whereas the growth of other plants such as aquatic grasses may decrease. Other aquatic organisms may become more sensitive and vulnerable to disease and their reproductive cycles may be disrupted with increased temperatures.

Causes and Sources of Water Pollution

Although pollution is often defined as contamination by harmful chemicals or waste materials, environmental pollution can be anything that harms or causes an imbalance in plants and animals in their natural habitat — even though the substance may not be harmful to humans. For example, phosphorus and nitrogen are common elementsA molecule composed of one type of atom. Chemists have recognized or created 112 different types of elements. Two or more different elements form a compound. of most fertilizers. They are not inherently harmful to humans. However, nitrogen runoff can be a pollutantSomething which contaminates (water, the air, etc.) with harmful or poisonous substances. in saltwater bays and estuariesThe wide lower course of a river where the tide flows in, causing fresh and salt water to mix., and phosphorus runoff can be a pollutant in freshwater habitats such as the Everglades and Lake Apopka and other freshwater lakes, because it causes an imbalance in the natural system.

Pollution is usually caused by human activities. Pollutants aren’t always detectable by smell, sight or taste. Water may look and smell clean and even taste fine, but it may still be contaminated and unsafe for drinking. Despite successes in cleaning up some water pollution, many modern pollutantsSomething which contaminates (water, the air, etc.) with harmful or poisonous substances. are very difficult to remove, and it is obviously better not to pollute in the first place. Heavy metalsMercury, lead, cadmium and nickel-highly toxic in very small quantities; can be fatal and bioaccumulate in environment-have cumulative effects in humans. and synthetic chemicals pose particular hazards to humans and other forms of life. Heavy metalsMercury, lead, cadmium and nickel-highly toxic in very small quantities; can be fatal and bioaccumulate in environment-have cumulative effects in humans., such as lead and mercurya heavy, silver-white, metallic element, the only metal that is liquid at room temperature; also called quicksilver. A virulent poison, dangerous to handle and work with., can interfere with production of hormones and with reproduction. Lead can further result in physical and mental developmental problems in children.

Other metals, such as copper and zinc, are less dangerous to humans but are toxicPoisonous, a substance that reacts with specific cellular components to kill cells. to aquatic life (Stauffer 1998). More than 10 million chemicals are manufactured today. Most are used in agriculture and industry. Some break down quickly, whereas others, like heavy metalsMercury, lead, cadmium and nickel-highly toxic in very small quantities; can be fatal and bioaccumulate in environment-have cumulative effects in humans., remain in the environment for decades. Fewer than 2 percent of these chemicals have been fully tested with regard to human health risks, and no health information is available for more than 70 percent of them (Stauffer 1998).

Water may be polluted in two general ways: by point source pollutionA specific source of water pollution , usually industrial effluent, as opposed to diverse sources of pollution of domestic origin and by non-point source pollutionThe diverse sources of pollution of domestic origin, usually from domestic sources. With point source pollutionA specific source of water pollution , usually industrial effluent, as opposed to diverse sources of pollution of domestic origin , the cause of the problem can be traced to a single source, for example, a pipe discharging waste from a factory. Non-point source pollutionThe diverse sources of pollution of domestic origin is more diffuse and originates from diverse sources over a wider area.

In the past, pollution from industrial and domestic point sources was common. Stronger regulations, new technologies and more advanced treatment of wastes have reduced point source pollutionA specific source of water pollution , usually industrial effluent, as opposed to diverse sources of pollution of domestic origin . Today most water quality problems result from non-point source pollution, including storm water runoff, septic tanks, runoffThe topographic flow of water from precipitation to stream channels located at lower elevations. Occurs when the infiltration capacity of an area's soil has been exceeded. It also refers to the water leaving an area of drainage. Also called overland flow. from croplands, dairies, feedlots and farms, and erosionTo wear away by the action of water, wind, or glacial ice. Removal of vegetation and trees can increase erosion of topsoil. from construction sites and unpaved roads. Non-point source pollutionThe diverse sources of pollution of domestic origin carries pesticidesA chemical that kills, controls, drives away, or modifies the behavior of pests. and fertilizers from lawns and fields, oil and greases from roads and parking lots, sediments from construction sites and clear-cutting of trees, and wastes from improperly functioning septic tanks.

In 1982, the state of Florida implemented a rule to reduce storm water runoff. Since 1982, all new developments have been required to use best management practices (BMPs) to minimize runoff during construction and to treat storm water after construction. These BMPs include requiring swales, retention ponds, detention ponds and detention ponds with filtration.

Florida Water Quality and Trends

Because Florida is so populous and has grown so rapidly, an important source of pollution, particularly of surface water, is urban Storm waterWater that results from a storm; can cause flooding and contamination of sewers.. Surface water quality problems occur with the greatest frequency in heavily populated areas — the southeast, in the central region near Orlando, in the St. Johns River basin particularly around Jacksonville, in Pensacola Bay and its tributaries, in the Peace River basin and along the west coast between Tampa and Naples. Water bodies whose watershedsCatchment area of a drainage basin. include large urban areas and intensive industry and agriculture have the poorest water quality. Developed areas have a much higher proportion of imperviousNot allowing fluid to pass through surface than rural areas. Impervious surfaces are covered with buildings or asphalt, concrete and other materials that prevent water from seeping into the ground. As a consequence, the volume of storm waterWater that results from a storm; can cause flooding and contamination of sewers. increases, carrying pollutantsSomething which contaminates (water, the air, etc.) with harmful or poisonous substances. with it.

The Effect of Covered Surfaces on Runoff
Source: Fernald and Purdum 1998; illustrating relationship of water distribution relative to degee of impervious to pervious areas.

Water Quality Monitoring

The Florida Department of Environmental Protection monitors water quality in over 600 surface water bodies throughout the state. Between 1986 and 1995, the water quality in 71 percent of these water bodies was unchanged, the water quality of 20 percent improved, and the water quality of 9 percent declined. In general, improvements were related to better control of point source pollutionA specific source of water pollution , usually industrial effluent, as opposed to diverse sources of pollution of domestic origin , particularly discharges from wastewaterUsed domestic water for disposal, from baths, showers, toilets, washing machines and the like treatment plants. Declines in water quality generally resulted from increases in storm water runoffThe topographic flow of water from precipitation to stream channels located at lower elevations. Occurs when the infiltration capacity of an area's soil has been exceeded. It also refers to the water leaving an area of drainage. Also called overland flow.. Florida’s ground water, as well as its surface water, is vulnerable to contamination.

Large portions of the state are covered with well-drained sandy soils overlying porous limestoneSedimentary rock composed of carbonate minerals, especially calcium carbonate. Limestone can be created by clastic and non-clastic processes. Clastic limestones are formed from the break up and deposition of shells, coral and other marine organisms by wave-action and ocean currents. Non-clastic limestones can be formed either as a precipitate or by the lithification of coral reefs, marine organism shells, or marine organism skeletons.. High amounts of rainfall contribute to the potential for contamination of ground water: in many places, anything on the surface is likely to percolate through to the ground water. Connection between ground water and surface water also means that anything found in surface water is likely to find its way into ground water and vice versa. In the 1980s, hundreds of wells in Florida were found to be contaminated with the soil fumigantA chemical compound used to purify with fumes Ethylene Dibromide (EDB).

Other wells were found to be contaminated with dry-cleaning solvent and gasoline from leaking underground storage tanks. This resulted in standards for water well construction and water testing within areas of known groundwaterWater in the ground. Water that occupies the pore spaces found in some types of bedrock. contamination. Ground water in Florida has also been found to be contaminated with nitrateForm of nitrogen commonly found in the soil and used by plants for building amino acids, DNA and proteins. It is commonly produced by the chemical modification of nitrite by specialized bacteria. Chemical formula for nitrate is NO₃-. from fertilizers or leachateSolution containing material leached from a soil. from septic tanks. Nitrate contamination of ground water may cause “blue baby syndrome”, a condition affecting human infants under 6 months of age. High levels of nitratesForm of nitrogen commonly found in the soil and used by plants for building amino acids, DNA and proteins. It is commonly produced by the chemical modification of nitrite by specialized bacteria. Chemical formula for nitrate is NO₃-. decrease the amount of oxygen carried in the baby’s blood. The skin around the eyes, mouth and feet appear blue. The syndrome may also cause difficulty breathing, loss of consciousness, convulsions and even death. When fertilizers are applied to anything growing in excess of wha can be consumed by growth percolates into ground water as pollutantsSomething which contaminates (water, the air, etc.) with harmful or poisonous substances. .

Human Imprints

Beginning in the 1800s, many of Florida’s natural systems were radically changed. Thousands of acres were drained for agriculture. Thousands more were drained for houses for the steady stream of new residents. Rivers were straightened and canals were dug for drainage and flood control and to make travel easier for ships and barges. Rivers were dammed for hydroelectric power and to create lakes for recreation. Forests were cut and trees were tapped for turpentine and rosin. In northern Florida, centuries-old long leaf pine trees were replaced with acre upon acre of fast-growing slash pine. Farther south, ancient cypress were logged and the land left bare.

Today, agricultural enterprises, businesses, houses, cities and roads cover 43 percent of the Florida landscape. Forests and wetlands comprise the other 57 percent. However, humans have left their imprint on nearly all of this remaining land. Most of the forests are now straight rows of young trees, the original trees having been logged. Also, many natural areas have been affected by invasive exotics (plants and animals from elsewhere) that “crowd out” native speciesSpecies that are originally found in a certain area. (Kautz et al. 1998).

Wildlife Impacts

A serious consequence of the conversion of the natural Florida landscape to human uses has been the fragmentation of remaining natural habitats. Water no longer flows unimpeded from uplands to coastal estuariesThe wide lower course of a river where the tide flows in, causing fresh and salt water to mix.. Wide ranging speciesA taxonomic category subordinate to a genus (or subgenus) and superior to a subspecies or variety, composed of individuals possessing common characters distinguishing them from other categories of individuals of the same taxonomic level. In taxonomic nomenclature, species are designated by the genus name followed by a Latin or Latinized adjective or noun. such as the endangered Florida panther and the black bear facehazards as they cross barriers such as roads and levees that isolate and fragment their habitats. Habitat fragmentation increases the amount of “edge” habitat. Although edges are desirable for some game species, such as deer and rabbits, and for some birds, such as song sparrows and cardinals, excessive amounts of edge are undesirable for interior forest dwellers. Edges of forests are also hotter and drier than the forests themselves and may become dominated by common weeds, whereas forest interiors are more diverse and support more rare species (Kautz et al. 1998).

Florida has responded to the loss, degradation and fragmentation of the natural environment with one of the most aggressive and farsighted land acquisition programs in the nation. As of March 2001, 8.7 million acres, covering nearly a quarter of the state, were publicly managed conservation lands (Florida Natural Areas Inventory, unpublished data). But public acquisition is not enough: there must be land management and in many instances, land restoration.

In the past century, conservation efforts focused on acquisition and preservation, basically putting a fence around what’s left, according to former U.S. Secretary of the Interior Bruce Babbitt. “We have finally come to recognize that that’s not enough. We cannot meet our obligation to the protection of creation by saying ‘fence off the back 40,’ put somebody in a uniform from the National Park Service here and say we’ve taken care of our obligation.” Today an “ecological revolution,” in Babbitt’s words, is occurring: it is ecological, not political, boundaries that are critical. You can’t preserve or manage or restore public lands in isolation from the landscapes of which they are a part.

Many things can be taken apart, but some, such as biological systems, are very difficult to put back together again. On the surface, a biological system may look like it’s “fixed,” but it might not work. Some parts may be missing, some may be forgotten or some may not be put back in the proper relationship to other parts. Complexity and diversity tend to be hallmarks of unaltered systems, and this makes restoration very difficult. Like a broken eggshell, a fragmented and altered ecosystem that is put back together may never be as strong and resilient as the original. In spite of these challenges, throughout Florida, ecosystemsa community of organisms, including humans, interacting with one another and the environment in which they live. are being “put back together”.