Water Quality Parameters

This section includes general information on various water quality parameters throughout the Basin Summary Report and discusses why these parameters are significant measures of the health of the stream system.


Potential Impacts: A high alkalinity will protect sensitive aquatic organisms from changes in pH. The acid-neutralizing or buffering capacity of water is essential for aquatic life to thrive.

Potential Causes: Naturally occurring alkalinity is determined by the rock strata in which water flows through. Sedimentary rocks, which are rich in carbonate, bicarbonate, and hydroxide compounds, are indicative of a high alkalinity. Conversely, granitic rocks and sandstones are associated with a low alkalinity.


Potential Impacts: Elevated levels of ammonia can injure or kill aquatic life, such as fish and invertebrates. In fish, even low concentrations of ammonia can damage sensitive tissues such as gills, can deplete natural resistances to bacterial infections, and can hinder reproductive capacities and growth.

Potential Causes: Ammonia occurs naturally as a byproduct of protein metabolism and decomposition. Ammonia can also enter a water body from runoff of fertilizers and livestock waste and from discharges of untreated sewage and industrial wastewater.

Chloride (Cl -1)

Potential Impacts: Although small amounts of chlorides are essential to proper cell function in plants and animals, large concentrations of chlorides can damage aquatic life physiology and hinder reproductive fertility and growth.

Potential Causes: Chlorides occur naturally from the weathering and erosion of sedimentary rocks. Agricultural runoff, industrial wastewater, petroleum industrial activities, salt water intrusions, and effluent from wastewater treatment facilities (WWTFs) are sources of chlorides.


Potential Impacts: Chlorophyll-a, as a photosynthetic pigment found in green plants is an indicator of the presence of algae in the water. It is used to monitor the trophic status of lakes or the primary productivity of ecosystems.

Potential Causes: Elevated levels of nutrients could result in high concentrations of algal biomass.


Potential Impacts: Dioxin is a family of polychlorinated chemicals. It is carcinogenic, and is detrimental to animal and human health.

Potential Causes: Dioxin is present in the waste from the paper bleaching process and from the combustion of chlorinated compounds.

Dissolved Oxygen

Potential Impacts: The most important component for the survival of aquatic life is oxygen. DO is essentially the amount of oxygen available in water. Low dissolved oxygen will suffocate aquatic species, and a high amount of dissolved oxygen will reduce water odors.

Potential Causes: Elevated levels of organic nutrients can cause an over abundance of bacteria and algae, which will deplete oxygen from water. Human-caused increases in water temperature will also lower the capacity for water to hold oxygen.

Bacteria (Escherichia coli, Enterococci)

Potential Impacts: Escherichia coli and Enterococci are bacterial indicator species for the presence of fecal matter, pathogenic bacteria and viruses.

Potential Causes: Malfunctioning or failing onsite sewage facilities (OSSF), untreated domestic sewage, disposal of grease and runoff from agricultural and livestock activities can cause an overabundance of bacteria and other pathogens.

In-stream Flow Instantaneous Flow (Quantitative), Flow Severity (Qualitative)

Potential Impacts: Flow conditions affect water quality. Aquatic species are adapted to specific in-stream flow patterns. Low flow events, which are associated with hot summer months, can severely alter a stream habitat. High flow events often associated with heavy rain or melting snow can also disrupt an aquatic habitat.

Potential Causes: Drought or heavy rain events can disrupt normal flow patterns. Impediments, such as fallen trees, beaver dams or man-made dams can disrupt or alter in-stream flow.


Potential Impacts: Mercury is a highly toxic metallic element. When it is entered into an aquatic habitat, it can bond to form methylmercury. Methylmercury will accumulate in the fatty tissue of aquatic organisms. Humans that consume fish and other aquatic organisms with high concentrations of methylmercury risk developing acute neural toxicity and birth defects.

Potential Causes: Mercury occurs from natural or man made sources. The most common is atmospheric deposition from the burning of fossil fuels and other industrial activities.

Nitrogen,Nitrate-(NO3-N), Nitrite-(NO2-N)

Potential Impacts: An abundance of nutrients can increase plant and algal growth. Bacteria use oxygen in the decomposition of plant matter, which can reduce dissolved oxygen. Nitrites are an intermediate form of Nitrogen that can cause "brown blood disease" in fish by preventing the transfer of oxygen by hemoglobin. Nitrites can also adversely affect human health, especially for young children under the age of three.

Potential Causes: Nutrient sources are usually found in runoff from fertilizers and livestock facilities. They are also present in the effluent of waste water treatment facilities (WWTF).

Polychlorinated biphenyls (PCB)

Potential Impacts: Polychlorinated biphenyls are acutely toxic, and can disrupt the endocrine and neural processes in aquatic life and humans.

Potential Causes: PCBs are found in dielectric fluids used in transformers, capacitors and coolants.


Potential Impacts: Aquatic organisms have evolved to live in a specific range of pH. Biological and chemicals processes can be altered or affected if the pH drops or rises over certain thresholds. Fish species cannot survive if the pH drops below 4 or rises above 12.

Potential Causes: Runoff from mining operations and discharges of industrial wastewater can alter the pH of a water body.

Phosphate, Orthphospate-P, Total Phosphate-P

Potential Impacts: The majority of the phosphorus compounds found in water are phosphates. Orthophosphate is consumed by aquatic plants and organisms and is considered the "limiting factor" of aquatic plant growth. High or excessive levels of orthophosphate will give way to a higher yield in growth. Excessive plant growth can cause eutrophication, (the natural aging progression of a water body) which will lower the levels of dissolved oxygen.

Potential Causes: Phosphates occur naturally from the decomposition of organisms. Sources also include the weathering of rock material and runoff from fertilizers.


Potential Impacts: Salinity is the measurement of conductive ions in the water. High levels of sodium sulfate and magnesium sulfate produce a laxative effect in drinking water. High levels of total dissolved solids can cause an unpleasant taste in potable water.

Potential Causes: Weathering or erosion of rocks, salt mining and salt water intrusions are sources for an increase in salinity.

Secchi Transparency

Potential Impacts: Secchi transparency is used to calculate the depth to which natural light can penetrate the water column. It also used as a measurement of eutrophication, the natural aging progression of a water body.

Potential Causes: An abundance of algae and plants or excessive levels of TSS will decrease the ability for light to transmit through the water column.

Sulfate (SO4-2)

Potential Impacts: In the absence of oxygen and with a pH below 8, bacteria will reduce sulfate ions to sulfide ions. Sulfide ions will cause serious and unpleasant odor problems. Sulfates in sediment can also alter soil compositions and hinder or prevent growth of native plants.

Potential Causes: Sulfate is derived from rocks and soils containing gypsum, iron sulfides and organic compounds. Sulfur containing fossil fuels, heavy industrial activities and some fertilizers are also potential sources for sulfates.


Potential Impacts: The types of aquatic life that can survive in a water body are dependent upon the water temperature. The water temperature can affect the levels of dissolved oxygen. Water with a high temperature will have less of a capacity to hold oxygen. As the water temperature drops, cold-blooded animals such as fish can become more susceptible to pathogenic stress or shock, which can lead to infections or death.

Potential Causes: Releases of water from reservoirs can contribute to drops in temperature. Temperatures will increase with the removal of flora from riparian areas or from the release of heated water from industrial activities.

Total Dissolved Solids

Potential Impacts: Elevated amounts of total dissolved solids can be corrosive upon sewer and plumbing fixtures. Also, high TDS will affect the aesthetic quality of water.

Potential Causes: Elevated amounts of TDS occur naturally from salt deposits, salt water intrusions, and sedimentary rocks high in carbonate. Salt mining, petroleum exploration, potable water treatments, wastewater discharges, and chemical, storm water, fertilizer runoff can increase the amounts of total dissolved solids.

Total Hardness

Potential Impacts: Total hardness is the measurement of ions such as calcium and magnesium. A high hardness concentration will prevent the toxic effects of heavy metal pollutants. An elevated hardness measurement is indicative of a high alkalinity.

Potential Causes: The weathering or erosion of sedimentary rocks will contribute to a high total hardness in a water body.

Total Organic Carbon

Potential impacts: Total Organic Carbon is the measurement of the amount of organic carbon in water. It can be used as an indicator of eutrophication, as well as in potable water treatment.

Potential Causes: TOC is released in the decomposition of organisms. It is also present in herbicides, pesticides, fertilizers, and detergents.

Total Suspended Solids

Potential Impacts: An increase in the amount of total suspended solids will decrease the ability for light to penetrate through the water column. This can decrease the productivity of aquatic plants. As excessive amounts of TSS settle and become sediment, benthic habitats can be altered or destroyed.

Potential Causes: High erosion events, usually coinciding with the removal of riparian floral species and severe flow events, will create excess levels of TSS. Unsound agricultural practices can also contribute to an influx of soil erosion into waterways.

Volatile Suspended Solids

Potential Impacts: Volatile Suspended Solids are the inorganic compounds found in a total suspended solids measurement. They can be used as an indicator for the amount of organic suspended solids found in a water body.

Potential Causes: Industrial wastewater can contribute to a high amount of volatile suspended solids.

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