Water Testing Guide: Turbidity, pH, DO, and More

1. Water Testing!

2. Turbidity • Turbidity is a measure of the cloudiness or the clarity of water. • Turbidity is measure in nephelometric turbidity units (NTU). • The more turbid the water, the cloudier the water.

3. It is measured by passing light through the water and seeing how much is reflected off particles in the water.

4. Levels • Ideal Level: 1 NTU • High Level: 5 NTU and above

5. Turbidity increases as a result of phytoplankton, algae growth, sediment from solid particles such as clay from erosion, particles moved around from the bottom of water, wastes. • These particles flow into the water most often during storms.

8. Results of high turbidity 1. Heat raises water temperature—Cloudy water absorbs more sunlight, raising the water temperature. Warmer water can't carry as much oxygen.

9. 2. Shade limits plant growth—Sunlight can't get through to rooted aquatic plants. Fewer plants mean less photosynthesis to release oxygen. It also means fewer homes and hiding places for insects and small fish.

10. 3. Congestion clogs respiration—Particles clog fish gills depriving them of oxygen which stunts their growth

11. pH • The abbreviation pH stands for potential hydrogen. • In scientific terms, what pH would stand for is ability of molecules to attract hydrogen ions. An acidic molecule would have a low ability to attract hydrogen ions, while an alkaline molecule would have a high ability to attract hydrogen ions.

12. pH • The pH of a solution is measured on a scale from 0 to 14. • Below 7: acidic • 7: neutral • Above 7: basic

15. The pH level of a body of water is important however it is most important to monitor the pH levels over a period of time to see if the levels are changing.

16. Causes of changes in pH • Amount of plant growth • Type of rock in the water (limestone, granite) • Runoff from farms • Dumping of chemicals • Acid rain • Coal mine drainage

17. What happens when pH levels change? • Changes in the pH value of water are important to many organisms. • Most organisms have adapted to life in water of a specific pH and may die if it changes even slightly. • This is especially true of aquatic macroinvertebrates and fish eggs.

18. Are there normal levels of pH? • There is no "normal" pH that applies to all fish. Because fish originate in ponds, rivers, streams, lakes, and oceans that have different pH levels, their needs are different.

19. Are there pH levels that fish prefer? • Saltwater fish prefer pH of 8 or above. • Freshwater fish thrive in a lower pH range somewhere between 5.5 and 7.5, depending on the specific species

20. Dissolved Oxygen (DO) • Amount of oxygen that is dissolved in water. • DO is essential for a healthy stream. • A small amount of oxygen, up to ten molecules of oxygen per million of water is dissolved in water.

21. How does the dissolved oxygen get there? • Oxygen enters a stream mainly from the atmosphere

22. Aquatic plants and animals use this oxygen for respiration. • Consistently high dissolved oxygen is usually considered ideal.

23. Rapidly moving water, such as in a mountain stream or large river, tends to contain a lot of dissolved oxygen, whereas stagnant water contains less dissolved oxygen.

24. Bacteria in water can consume oxygen as organic matter decays. • Excess organic material in lakes and rivers can cause eutrophic conditions, which is an oxygen-deficient situation that can cause a water body "to die.”

25. What can cause changes in DO? • Photosynthesis is the primary process affecting the dissolved-oxygen/temperature relation; water clarity and strength and duration of sunlight, in turn, affect the rate of photosynthesis.

26. Dissolved oxygen levels can also change with temperature • Warmer temperatures= lower dissolved oxygen levels. • Cooler temperatures=more dissolved oxygen levels

27. Conditions may become especially serious during a spate of hot, calm weather, resulting in the loss of many fish. You may have heard about summertime fish kills in local lakes that likely result from this problem. (share article about Neuse Fish Kill)

29. What are levels of DO? • Average Level: 9.0 ppm • Must be 4-5 ppm to support diverse population of fish

31. Results of Changes in DO • When DO drops too low fish die. As salinity increases, DO decreases. • Cold water can hold more oxygen than warm water, because as water heats up the water molecules begin to move further apart from each other, causing oxygen to escape. • Oxygen can be used up by decomposing material or excessive plant growth due to fertilizers.

32. Temperature • Changes in temperature can make aquatic life susceptible to disease and at extreme levels can result in death • Most fish cannot tolerate temperatures below freezing or above 97 degrees

33. Nitrates • important nutrients that plants and animals depend on for survival. • Nitrates appear in water systems in the form of bacteria from chemicals and septic tank leaks.

34. Nitrates are a major ingredient in fertilizer. • Nitrates from fertilizer enter the water supply by run off from farm land, gardens, lawns, herbicides and animal feces.

35. Causes of Nitrates • fertilizer runoff (both farm and home) • manure pits • leaks in septic systems • animal waste • rain trapping car exhaust

36. Nitrates are important for water quality because excess amounts increase the growth of algae . • Large growths of algae reduce the oxygen level, making the water unsuitable for water animals and fish could die.

37. Bio-indicators • Bio-indicators: macroinvertibrates found living in water that are sensitive to pollution

38. High Level of bio-indicators: healthy water source • Low Level of bio-indicators: poor water source (indicator of high levels of pollution)

39. Causes of change in bio-indicators • pollution that results in changes in pH • Temperature • dissolved oxygen, or nitrate levels

40. Results of few varieties of bio-indicators present: the lack of a large number of different varieties of bio-indicators shows pollution

41. Coliform Count • The number of disease causing organisms in a water sample.

42. EPA standards of coliform • Drinking Water must have 0 colonies / 100 mL • Swimming can’t be over 2000 colonies / 100 mL

43. If coliform is present, the water cannot be used as drinking water. • If the coliform is high, the water cannot be used for recreational purposes, such as, swimming and skiing.

44. Causes of bacteria • Animal and human waste getting into the water.