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2014 Water quality status and trends report

Surface water

Note: See Method page for definitions and acronyms used in this section.




(platinum-cobalt units)

Color — A measure of water transparency that is usually caused by particulates and dissolved organic materials, and influences the availability of light for photosynthetic organisms.

Corrected chlorophyll-a

Corrected chlorophyll-a — A green pigment found in all plants that facilitates photosynthesis and provides an estimate of algal biomass. Corrected means that pheophytin, a natural degradation product of chlorophyll, has been “subtracted out” of the result. High concentrations of chlorophyll reduce water clarity and limit the light available to shallow-water ecosystems.

Dissolved ammonia nitrogen
(µg/L as N)

Dissolved ammonia nitrogen — An inorganic form of nitrogen that serves as a nutrient for aquatic plants and algae. Ammonia nitrogen can be converted to nitrite and nitrate by bacteria (nitrification). The dissolved fraction is from a filtered water quality sample.

nitrite and nitrate
(µg/L as N)

Dissolved nitrite and nitrate — Inorganic forms of nitrogen that serve as nutrients for aquatic plants and algae. Although these are formed by the process of nitrification, other sources include fertilizers, atmospheric deposition and runoff. The dissolved fraction is from a filtered water quality sample.

Dissolved oxygen

Dissolved oxygen (DO) — Oxygen is required by fish and other marine organisms, and its concentration in water is heavily influenced by photosynthesis, water movement and water temperature. Natural conditions—such as groundwater from springs, water from swamps/wetlands, higher water temperatures, and calm and cloudy weather—can also decrease DO levels in water bodies.

(mg/L as CaCO3)

Hardness — An indication of the mineral content of the water, expressed as an equivalent amount of CaCO3. Florida’s groundwater is hard, due to interaction with limestone in the aquifer.

(standard units)

pH — An indication of water acidity on a scale of 0 to 14. A number less than 7 means the water is acidic, while a number greater than 7 means that the water is basic. Changes in pH can be caused by atmospheric deposition (acid rain), geology, vegetation and pollution.

(parts per thousand)

Salinity — A measure of the concentration of salts in water, usually in parts per thousand. Salinity determines what type of biota are found in an ecosystem.

Secchi disc transparency

Secchi disc transparency — A measure of water transparency with the use of a disc that has alternating black and white quadrants. A greater Secchi depth means a greater depth of water clarity.

Specific conductance
(uhmhos/cm @ 25° C)

Specific conductance — A measure of water’s resistance to electric current, and functions as an indirect measurement of the water’s salt content. Salinity and specific conductance are well correlated.

Total alkalinity
(mg/L as CaCO3)

Total alkalinity — A measure of water’s ability to neutralize acids (buffering capacity), usually measured in mg/L of CaCO3. More buffering capacity means higher resistance to a pH change as a result of the addition of acidic inputs, such as rain.

Total calcium
(mg/L as Ca)

Total calcium — An abundant alkaline earth metal always found in ionic form in water and an essential mineral for most plants and animals.

Total chloride

Total chloride — An ionized form of the element chlorine, which can be harmful to plants and animals in excess.

Total Kjeldahl nitrogen
(µg/L as N)

Total Kjeldahl nitrogen — The sum of organic and ammonia nitrogen, and can serve as an indicator of pollution.

Total magnesium
(mg/L as Mg)

Total magnesium — A common element essential to plants and animals, and is found in high concentrations in hard water.

Total nitrogen
(µg/L as N)

Total nitrogen — An element found in organic and inorganic forms that contributes to the growth of aquatic plants and algae. It is the sum of total Kjeldahl nitrogen and nitrite and nitrate.

Total organic carbon
(mg/L as C)

Total organic carbon — A measure of the organic carbon-bearing molecules in a water sample, and usually derived from decaying plant material in swamps and wetland areas.

Total phosphorus
(µg/L as P)

Total phosphorus — An element found in organic and inorganic forms that contributes to the growth of aquatic plants and algae.

Total potassium
(mg/L as K)

Total potassium — An essential element for plants and animals, and is generally found at higher concentrations in marine waters.

Total sodium
(mg/L as Na)

Total sodium — An essential element for plants and animals, and is generally found at higher concentrations in marine waters.

Total sulfate
(mg/L as SO4)

Total sulfate — An oxidized form of sulfur that has both natural and anthrophogenic sources, and can serve as an indicator of water hardness.

Total suspended solids

Total suspended solids — A measure of the amount of non-dissolved substances and particulates in the water. Higher concentrations of total suspended solids are often associated with reduced water clarity and higher color.


Turbidity — A measure of water transparency based on the scattering of light through the sample. Turbidity and total suspended solids often correlate well at individual sample stations.

Water temperature

Water temperature — Varies seasonally and influences plant and animal growth rates and behavior.

Note: The trend analysis demonstrates change during the report time period. This report does not attempt to analyze the cause of any change, nor the impact of any change.


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