water quality notes

Water Quality Indicators Notes

Using the presentation, fill in the chart for each water quality indicator.

Name of IndicatorIndicatesWhat does the test tell us about the water?Healthy IndicatorsWhat results would we expect to see if the water was good water quality?Causes What causes the water to be poor water quality?Impact If the water was not good quality for this indicator, what would happen?
Acidity (pH).If the water is more acidic (less than 7) or more basic (more than 7)Living things can survive within specific ranges of pH (6.0 -7.5)Contamination by industrial waste, agricultural and urban runoff, or drainage from mining operationsWhen the pH is outside of the healthy range, organisms can become ill or die
Turbidity.The amount of dirt and microscopic organisms are floating in the water. The more murky (cloudy) the water, more turbid the water is.Lower turbidity, clearer waterTurbid water results from soil erosion, urban runoff, and bottom sediment disturbancesIf water is more turbid, then less sunlight can reach the plants. This results in less organisms that can live in the water.
Bacteria (fecal coliform).If fecal coliform or other disease causing bacteria are in the waterNo fecal coliform is presentBacteria enter the water through runoff from farms or sewage discharge.Swimming in or drinking from waters with high fecal coliform levels can increase a person’s risk of getting sick
Dissolved oxygen.The amount of oxygen that is dissolved in the water. Dissolved oxygen increases with cooler temperatures and more turbulence (movement of water)High levels of dissolved oxygenExcess algae growth that dies and decomposes, using up the oxygen in the waterLow levels of dissolved oxygen makes it difficult for aquatic animals to live
Plant growth.Thick plant growth in the water indicates the water contains large amounts nitrates and phosphatesBalanced ecosystem with natural amount of plant materialExcess runoff containing nitrogen and phosphorus from fertilizers, farms, sewage and detergentsLight cannot reach deeper areas; creation of dead zones with low oxygen levels
Macroinvertebrates.The level of pollution in the waterA wide variety of macroinvertebrate species (organisms including aquatic insects, crayfish, clams, snails, and worms), especially those that are intolerant to pollution, are found.Pollution and sediment enters the streamPoor water quality can affect the types and number of organisms that can live in the water