Water Quality

Water Temperature:  Life in the aquatic environment is dependent upon the temperature of the water. For aquatic species, the temperature of the water regulates their life processes (metabolism), their ability to survive, and their ability to reproduce. Water temperature also affects decomposition of biological waste found in both the water and the bottom sediments. Increased decomposition produced by elevated water temperature can cause dissolved oxygen levels to decline, resulting in the death of stream organisms, including fish. The streams in Jefferson County suffer from elevated water temperature during the summer months primarily due to the removal of trees along stream banks (riparian area). The loss of shading elevates water temperature in the streams, lowers dissolved oxygen levels and frequently results in fish kills.

pH:  The pH of a stream is the measure of how acidic or basic the water is. If the stream becomes either excessively acidic or basic, it can have a very negative impact on aquatic life. Low pH can be caused by the introduction of organic material during low flows. High pH can be produced by increased photosynthesis (plants using sunlight to create stored energy), or by wash-off of lime applied to croplands, golf courses or lawns. Most streams in Jefferson County have pH in normal limits.

Total Suspended Solids:  The term total suspended solids (TSS) is a description of the organic and inorganic material suspended in water. There is a considerable problem in Jefferson County with suspended solids in streams. The solids settle out and accumulate on the bottom producing seriously altered streambeds. Interaction between the chemicals in the sediments and the suspended solids reduce dissolved oxygen levels in the water. The accumulation of sediments on the bottom can also eliminate suitable habitat and clog the gills of stream organisms.

Suspended solids originate from construction sites, farms, lawns, streets, parking lots, and commercial sites as storm water washes off of these areas. Suspended solids can also arise from combined sewer overflows, as sewer lines fill with storm water beyond their capacity to transport. There is an Erosion Prevention and Sediment Control Ordinance in development for Jefferson County that could reduce suspended solids originating from construction sites. Soil erosion is one of our top water quality problems.

Total Dissolved Solids:  Total dissolved solids (TDS) consist of salts, organic matter and dissolved materials. Most aquatic life can tolerate a relatively high range of variation for dissolved solids. However, some dissolved solids can be introduced in sufficient quantities to produce negative impacts on aquatic life. Runoff from streets and parking lots, particularly in winter when salts are applied, can produce aquatic conditions unsuitable for life in streams. Runoff from chemically treated lawns, golf courses and croplands can also produce inhospitable conditions in streams. Lawn chemicals are regularly detected in all of our local streams.

Nutrients:  Nitrogen and Phosphorus found in streams are generally referred to as nutrients. Nutrient levels in most Jefferson County streams are often high and result in serious reduction of health in aquatic communities. Typically, high levels of nutrients can arise from a variety of potential sources including treatment plant discharge, septic tank seepage, combined sewer overflows (CSO), sanitary sewer overflows (SSO), runoff of fertilizers, or animal waste products. Nutrients in aquatic systems may result in increased abundance and growth of both rooted vegetation and algae in streams. This problem will increase if trees are removed from stream banks, increasing sunlight and resulting in excessive growth of algae. This excessive growth of algae can cause underlying mats of algae to become shaded, and the result can be mass die off of these underlying mats. The decomposition of dead algae can cause increased oxygen use and result in low dissolved oxygen levels. Fish kills can occur in Jefferson County streams as a result of a combination of elevated water temperature and nuisance levels of algae growth.

Metals:  Metals are important pollutants because they can produce toxicity (harmful health affects) in streams. High metals content can have negative impacts on aquatic communities. Metals sampled and tested include Arsenic, Beryllium, Cadmium, Chrome, Copper, Iron, Lead, Mercury, Nickel, Selenium, Silver and Zinc. Every stream sampled in Jefferson County has had metals at levels that sometimes exceed the limits set by the Kentucky Division of Water (KDOW). Studies have shown that metals violations can be the result of natural geology. The shales in this area are well known for metals content and may contribute to metals violations in Jefferson County streams. Atmospheric fallout can also be a potential source for metals, especially toxic metals like mercury and lead that have proven to be harmful in very small quantities.

Pesticides and Herbicides:  On a seasonal basis, several pesticides and herbicides have been found in stream water, particularly after storm events when they are washed off the surrounding land. They are of concern because, like metals, they can produce toxic effects. Several different pesticides (chemicals used to kill unwanted pests) and herbicides (chemicals used to kill unwanted plants) are sampled within each stream.

Bacteria sampling:  Bacteria samples are taken monthly for fecal coliforms and fecal streptococcus. Fecal coliform and fecal streptococcus are bacteria found in the intestines and feces of warm-blooded animals. Fecal coliform and fecal streptococcus, if present in water, may indicate possible sewage contamination and the presence of contagious diseases, such as Hepatitis. Violations of bacteria levels were based on primary and secondary recreational (swimmable / fishable) contact standards, as published by KDOW. All stream stations sampled in Jefferson County had numerous violations for recreational contact, and none of the sampled streams were suitable for recreational use.

Macroinvertebrate Sampling:   Macroinvertebrates are invertebrates that are large enough to be seen with the naked eye. These may include aquatic insects, snails, clams, mussels, crayfish and worms. The macroinvertebrate community structure can provide information on the health of a stream. Over extended periods of time, the types of macroinvertebrates present can reflect water quality and/or habitat quality of a stream. Among the types of water quality conditions that affect macroinvertebrates are metals toxicity, sedimentation, nutrient enrichment, dissolved oxygen stress, and temperature stress. Macroinvertebrate communities in Jefferson County streams generally indicate moderate to severe levels of impact on either water quality and/or habitat quality.

Criteria:  The parameters monitored in Jefferson County streams are based on standards established by the Kentucky Division of Water (KDOW) in the administrative regulations: 401 KAR Chapter 5 Water Quality 1995. The streams in Jefferson County are classified as Warmwater Aquatic Habitat. Many of the parameters are narrative standards that allow no adverse affect on the aquatic community. Other parameters have been developed with set ranges or a minimum / maximum allowable level. Standards have been established for alkalinity, pH, flow, temperature, dissolved oxygen, solids, ammonia, toxic substances, metals, some pesticides, some organics, chlorides, chlorines, cyanides, hydrogen sulfide, and fecal coliforms.

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