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Management and Monitoring
Field measurements are collected for every water body sampled.
Dissolved oxygen, pH, specific conductance, and water temperature are
measured using a field meter. These measurements are conducted in
accordance with DEP Standard Operating Procedures (SOPs). Other
observations included with the field measurements are cloud cover, wind
direction, wind velocity, and air temperature. Weather conditions and
other events that could affect the water quality or result in analytical
results that are not representative of a water body (i.e. flooding,
heavy rains, drought conditions, etc) are also recorded.
Dissolved Oxygen - Oxygen
dissolves in water from both atmospheric and biological sources.
Oxygen gets into water by diffusion from the surrounding air, by
aeration (rapid movement) and as a waste product of photosynthesis.
The amount of dissolved oxygen gas is highly dependent on
temperature. Dissolved oxygen is essential for aquatic life. Algae
blooms, high nutrient levels, and seasonal conditions can result in
low or very high levels of dissolved oxygen levels which can result
in fish kills, among other things.
pH - This is a measurement of
the acidity or alkalinity of water. Values range between 0 and 14.
A low pH (below 7) represents acidic conditions, and a high pH
(above 7) represents alkaline conditions. A pH of 7 indicates the
water is near neutral conditions. Several factors influence the pH
of a water body including acid precipitation, bedrock and soil
composition, plant growth, organic material, and possible chemical
Secchi Depth - Secchi depth is
measured with a Secchi Disk. Secchi depth measurements are related
to turbidity, chlorophyll, and color in that all relate to water clarity.
- Specific Conductance − Specific conductance is a measure
of the ability of a liquid, to conduct electricity. The
conductance is a function of the amount and type of ions in the
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Alkalinity - Alkalinity is a measure of water's capacity to
neutralize acids. Alkalinity is important because it keeps the pH of a
water body constant in spite of changes due to acid rain or other
sources, protecting aquatic life.
Ammonia (NH3) - Ammonia is used as a fertilizer. Even very
low concentrations of ammonia can be toxic under the certain conditions.
As a nutrient, ammonia can contribute to eutrophication of water. An
abundance of nutrients in water leads to excess plant growth and
eventually to eutrophication.
Biochemical Oxygen Demand (BOD-5) − BOD is a test for
determining how much oxygen is utilized by microorganisms during a 5 day
incubation period. High BOD levels can have detrimental effects on a
water body including fish kills.
Calcium - Calcium salts and calcium ions occur commonly in
nature. Calcium is an important contributor to water hardness. Calcium
can reduce the toxicity of many chemical compounds making it very
important to aquatic life.
Chloride - Chloride is the most abundant component of
seawater. Sources of chloride include human and animal waste and
saltwater intrusions. High levels of chloride can harm metallic pipes
and inhibit growing plants.
Chlorophyll a - Chlorophyll a is a green pigment found in
plants. Chlorophyll a measurements are used to estimate phytoplankton
biomass. Levels of Chlorophyll a in surface waters naturally fluctuate
over time. Consistently high levels are indicators of poor water quality
and may be a result of excess nutrient loading.
Color - Color is not an indicator of water quality. Some natural
metallic ions, plankton, industrial wastes, and weeds are sources that
affect the color of water. Water bodies can be naturally tannic, or tea
colored, from the presence of tannins.
- Fecal Coliform bacteria are found in the fecal
waste of warm blooded animals. While some of these bacteria are not harmful,
they are indicators that pathogens may be present. Analysis results are
used to assess the sanitary quality of the water. High levels of fecal coliform bacteria can result in low dissolved oxygen levels.
Fluoride may occur naturally in waters or added in controlled amounts.
It is commonly found in drinking water as a method of reducing dental
carries. Too much fluoride can be harmful to human health. Fluoride in
surface water is mainly derived from natural minerals in rocks and soil.
Magnesium - Magnesium ions may contribute to water hardness.
Varying concentrations of magnesium and calcium in a water body can play
a role in the distribution of aquatic life.
Nitrate + Nitrite (NO3 + NO2) as N
- Nitrate and nitrite are
naturally occurring nutrients that contain a nitrogen atom joined to
oxygen atoms, with nitrate containing three oxygen atoms and nitrite
containing two. Nitrates in water bodies typically originate from
fertilizers, septic tanks and animal waste from runoff or seepage into
groundwater. Nitrates encourage plant growth. An abundance of nitrates
in water leads to excess plant growth and eventually eutrophication of
the water if the sources are not addressed.
- Total Organic is one of several measurements
of the organic content in water. The presence of organic contaminants in
waters may degrade ion exchange capacity or serve as a nutrient source
for undesired plant growth. An abundance of nutrients in water leads to
excess plant growth and eventually eutrophication of the water if the
sources are not addressed.
Orthophosphate (PO4) - As a
nutrient, orthophosphate can contribute to eutrophication of water.
An abundance of nutrients in water leads to excess plant growth and
eventually to eutrophication. Sources of
phosphate include organic and inorganic fertilizers, animal waste, human
waste effluent and industrial waste.
Potassium (K) - Potassium is important for both plant and
human nutrition. Sources include groundwater (mineral dissolution),
decomposing plants, and agricultural runoff.
Sulfate (SO4) - Sulfate occurs naturally in water with a
large range in concentrations. Unnatural sources of sulfate include
agricultural, disposal, and industrial waste.
Total Dissolved Solids (TDS)
- Solids are suspended or
dissolved matter in water. TDS measures the combined amount of inorganic
and organic substance dissolved in water. It is not a measure of water
quality but an indicator of the presence of chemical contaminants.
Total Kjeldahl Nitrogen (TKN) − TKN measures the sum of
ammonia and organic nitrogen in water. An abundance of nutrients in
water leads to excess plant growth and eventually to eutrophication.
Total Nitrogen - The sum amount of nitrate, nitrite, ammonia,
and organic nitrogen of water. An abundance of nutrients in water leads
to excess plant growth and eventually eutrophication of the water if the
sources are not addressed.
Total Phosphorus - Elemental phosphorus is toxic. In nature, it
exists as phosphates. Phosphates exist in three forms: orthophosphate, metaphosphate, and organically bound phosphate. Total phosphorus is the
sum of these concentrations. An abundance of phosphate in a system can
result in excess plant growth and eventually to eutrophication if it is
the growth-limiting nutrient of that system.
Total Suspended Solids - This refers to the amount of solid
material suspended in the water. It differs from turbidity in that it
provides the actual weight of suspended matter.
Turbidity - Turbidity is a measure of the colloidal suspension
of tiny particles and precipitates in spring water. High turbidity water
blocks light from penetrating the water which can be harmful to aquatic
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