Introduction A popular, and lucrative type of housing development in the coastal and piedmont environments of North Carolina, consists of canals dug shoreward from rivers and theconstruction of houses along these canals.  The canals give homeowners easy boat access to the rivers or estuaries adjacent to the development.  Water  in dead end canals would seem to become stagnant and propagate growth of micro-organisms and the build up of undesirable chemicals, especially nutrients and heavy metals.  The research performed will measure several microbiological and chemical

Testing Methods

Two sample sites were set up for each canal, one at the entry way of the canal and the second at the end of the canal.  Each site was tested weekly at various hours of the day to ensure a total review of each site.  The testing parameters included; temperature, conductivity and total dissolved solids, Power of Hydrogen, scherichia Coli or E. coli, total coliform, nitrates, phosphates, dissolved oxygen, time, and sky conditions.

Temperature

The temperature of a body of water is important to the inhabitants of that environment.  Temperature of water is influenced by many different factors;  the color, darker and muddier waters are able to retain heat from the sun at a higher rate than any clear body of water.  The depth and volume of a water way are also key factors, the deeper and wider the waterway is, the longer it will take for the water to gain heat.  Another factor that plays a role in temperature is the amount of vegetation surrounding the waterway blocking the sun, reducing the amount of heat the water receives.  The latitude and the time of year is able to manipulate the temperature of water in many environments.
 

Climates and seasons fluctuate, which means that the amount of heat varies, cold in the winter and hot in the summer.  Lastly, the temperature of waterways contributing to the canals has an effect on the temperature of the canal.  The water may be from an mountain stream, a river, or a vast water body, like an ocean.  All these factors work together to influence the temperature of one small body of water and influence the life that is able to survive in these waters.

Most aquatic life must have a particular range of temperature in which there is optimum growth and comfort.  Fish and most aquatic organisms are cold-blooded, when the water is cold, a fish has a low metabolic rate versus when the water is warm, they have a higher metabolic rate.  Most fish can survive comfortably between 0º and 36º Celsius, if the temperature goes any lower or higher than that range, many fish will become unproductive and may migrate to more suitable environments, or they may die.

Conductivity and Total Dissolved Solids (T.D.S.)

Conductivity is the measure of a solutions ability to conduct electricity. Conductivity is directly related to T.D.S., as well as the purity of water.  Total Dissolved Solids are salts or dissolved solids, such as chlorine, nitrate, sulfate, phosphate, sodium, calcium, and other anions that come from stones and soils in the river bed.  T.D.S. are the salts that are able to conduct electricity, therefore the higher T.D.S. the high the rate of conductivity and the lower T.D.S. the lower the rate of conductivity.

Plants and animals need salts within their nutrient intake to survive, but high salt levels can become extremely toxic for the environment and limit the growth to those plants and animals with a low tolerance for salts.  On the other side of the coin, low levels of salts as nutrients can become a limiting factor in an ecological area, and will not be able to support the life in that environment.

Power of Hydrogen  (pH)

 The pH of water is the balance of hydrogen ions (H*) and hydroxide ions (OH-) within the water.  The more hydrogen ions there are, the more acidic the water is, and the more hydroxide ions within the water, the more basic it will be.  The scale begins with 0 and increases to 14 by

by powers of ten.  The lowest numbers being the most acidic and the highest numbers being the most basic, with 7 being the neutral factor.  Fresh water environments are very fragile to acidic types of pollution, they do not contain as many salts to act as buffers to enable them to maintain a neutral balance.  Most fish and aquatic organisms can withstand pH levels between 5.0 and 9.0, but most fish prefer levels between 6.5 and 8.2. Most fresh water nvironments have been destroyed by acid rain, and industrial and residential contamination. These types of pollution may lead to synergistic effects.

Synergistic effects are when two elements are introduced into a particular environment, they produce effects greater than their original sum.  For example, a particular fish may be able to survive in water at a pH of 4, but the metal ions that begin to react at that particular pH can cause toxic water that the fish cannot survive in.

Microbiology

Bacteria are usually harmless to man, as humans we have many types of fecal coliform within our intestines that aid in the digestion of food.  Some of these bacteria that are released into aquatic systems are considered pathogens and can cause various illnesses, such as typhoid fever, viral infections, gastroenteritis, and hepatitis A.  Much of the bacteria in water comes from the the species that do inhabit the water.  This type of pollution is natural and the environment is able to break these pollutants down, but the most dangerous and pathogenic bacteria come from the waste and feces of warm blooded animals, like humans.  These contaminants are released into waterways through overflow of domestic waste, faulty septic tanks, and illegal waste disposal methods. Those people and animals that inhabit or are exposed to the dangerous waters, can be presented with serious health risks.

Escherichia Coli is the most common bacterial contaminate in the waterways and are generally found in the intestines and feces of warm-blooded animals.  According to the United States Environmental Protection Agency study in 1986, the mean average of total colonies of E coli. should not exceed 126 colonies per 100 milliliters.  This total is said to correlate to about eight swimmers per one thousand to develop a gastrointestinal illness.  If the levels exceed this standard then there should be cause for concern in areas of recreation.

Total Coliform is the collective amount of fecal waste, from warm-blooded animals, and all other species of life within the environment.  This is pollution count is important, however, it does not carry the high risks of disease that E. coli. carries.
 
 

Nitrates

The bases of growth and development of species is based on several different natural cycles, one of these is the nitrogen cycle. This cycle is very complex and has a careful balance; to upset this balance can lead to terrible consequences.

Nitrogen makes up about 78% of the air we breathe daily.  Even though nitrogen surrounds everything on the earth, excesses of nitrates in water bodies can cause environmental roblems.  Nitrogen generally enters water in the form of nitrites, which are converted to nitrates by acteria and algae through a process that depletes the amount of available oxygen in the water for fish and other aquatic organisms.  Increased amounts of nitrates in the water allows for uncontrollable growth of algae, called algal blooms.  An algal bloom is a condition where excessive nutrient levels cause rapid growth of algae.  An algal bloom can cause change in the color of the water and will reduce the amount of dissolved oxygen available for aquatic life.  High levels of nitrite, if not quickly converted to nitrates can lead to a serious condition in fish called, “brown blood disease”.  High levels of nitrites can cause harm to humans, by causing hemoglobin, the oxygen carrier in blood, to produce methemoglobin, which destroys the ability of red blood cells to carry oxygen.

 Major contributors in high nutrient levels of water may be; lawn and farm run fertilizer run off, animal waste, industrial waste, car exhaust and leaking septic tanks.

Phosphate

 The phosphate cycle is another important cycle within the environment, it is essential to the growth and development of plants.  Phosphate is usually the limiting factor in photosynthesis

for plants, zooplankton, and bacteria.  High phosphate levels in waterways contribute to the destruction of a once ecologically stable area in a similar way as nitrogen.  The fact that phosphate is generally the limiting factor in plant evelopment,  indicates that when there are high levels of phosphates in the water then there is cause for concern of algal blooms, which can kill off a body of water.

The recommended maximum phosphate-phosphorus level for rivers is 0.1
mg/L (Hach).  High levels of phosphate can come from industrial waste, and
lawn and farm fertilizer run off.

Dissolved Oxygen “DO”

 All higher forms of life require oxygen for survival.  Fish and other aquatic organisms require their oxygen in the form of dissolved oxygen or DO.  Oxygen is able to enter into rapidly moving water or water that has been moving in waves or over waterfall wherever it has the ability to exchange with oxygen in the atmosphere and aerate itself.  Moving streams or rivers generally contain high amounts of DO; where as non-circulating water is stagnating with very little DO.

 Most aquatic organisms are able to sustain life in areas where DO levels are between 3 mg/L and 5 mg/L.  Any less DO in the water is considered to low to support any substantial amount of life.
 

Several conditions can lead to low levels of DO; nonmoving water,such as in canals; high levels of nitrates and phosphates, which cause algal blooms; and warm water, which does not have the ability to hold dissolved oxygen very well.  Effects of the low DO levels are fish migrations, algal blooms, fish kills, and an overall consequence of a “dead” body of water that is unable to sustain any life.

 
 
 

Winslow Acres  Length            = 1/4 mile  Width             =  10 yards  Contributory   =  Pasquotank River    Special Notes and Observations: No algae build up  Many fish inhabiting the canal  High boat traffic within the canal  Week of 6-7-99 had above average levels of E. coli  Week of 6-7-99 had above average levels of phosphates

 

 *     Higher than normal levels of  phosphates
 *     Above normal level of E. coli  toward the tail of the canal.  Residents along the canal who do use the
        canal for recreational purposes should know that there is a greater than 8 in 1000 chance that gastro-
        intestinal problem will occur.

Dances Bay  Length  = ±250 yards  Width   =  7 yards  Contributory  = The Little River    Special Notes and Observations:  High algae growth (tail)  High fish content in the earlier parts of May ‘99  Unable to locate any fish in June

• Below average dissolved oxygen levels  in weeks 6-14-99 and 6-28-99 (tail)
• Higher than normal phosphate/phosphorus levels (head and tail)
• Located in a farming area

 

 
 
 
 
 



*  Higher than normal levels of phosphates

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Hobbs Landing  Length   = 50 yards  Width   = 4 yards  Contributory  =  Little River  Special Notes and Observations : Ducks and other wildlife inhabiting area  Swamp like conditions located behind the canal  High algae growth  Few to no fish able to live in the canal  Located in a farming area  Below inhabitable levels of dissolved oxygen from week 5-30-99 through 6-28-99



*  Low levels of dissolved oxygen may lower the chances of any aquatic life within the canal.

*  High levels of conductivity generally indicate high levels of salts or a higher salinity.   Since these are
    fresh waters high salts are irregular and thus a destructive factor for aquatic life.

*  Above normal level of E. coli  toward the tail of the canal.  Residents along the canal who do use
    canal for recreational purposes should know that there is a greater than 8 in 1000 chance that gastro
    intestinal problem will occur.

*  High levels of phosphates may be from farm fertilizer run off or any other non point source.

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Nixonton Terrace  Length  = 100 yards  Width   = 7 yards  Contributory  =  Little River   Special Notes and Observations:  Boats and other watercraft docked in the water / possible gas and oil leaks  Many fish within the water  Recreational activities within the canal  Above average levels of E. coli during week of 6-21-99 near mouth of the canal

*     High levels of nitrates may be from farm fertilizer run off or any other nonpoint source.
*     High levels of phosphates may be from farm fertilizer run off or any other non point  source.

Halls Creek Trailer Court  Length   = 65 yards  Width   = 6 yards Contributory  =  Halls Creek    Special Notes and Observations:  Ducks and other wildlife inhabit the area near the canal  Trash and debris buildup at the tail of the canal

• Algae growth at the tail of the canal
• Bad odor or stench coming from the water.
• Below average levels of dissolved oxygen during weeks 6-21-99 and 6-28-99
• Located in a farming area

*     Abnormal levels of E coli. towards the tail of the canal.  Residents along the canal who do use the canal
        for recreational purposes should know that there is a greater than 8 in 1000 chance that gastro-
        intestinal problem will occur.  High E. coli levels may be from the ducks and other wildlife, as well as
        faulty septic tanks.

*     High levels of nitrates near the mouth of the canal which may be from farm fertilizer run off or any other
       non point source.

*     High levels of phosphates throughout the canal which may be from farm fertilizer run off or any other
        non-point source.

Pike Road  Length  = 1/4 mile  Width   = 7 yards  Contributory  =  Little River    Special Notes and Observations: Very long canal  Fish within the canal  Located near  farm areas

*     High levels of phosphates within the canal which may be from farm fertilizer run off or any other non-point
        source

Dissolved Oxygen

• The