TURBIDITY

A measure of the dispersion of light in a column of river water due to various things suspended in the water. These suspended materials include mud and other non-living things, as well as algae and other small forms of life.

INSTRUCTIONS FOR USING TEST KIT:

1. Place the two turbidity tubes on a piece of clean white paper. Place a sample of river water in one and a sample of distilled water in the other. It is important that both samples be properly measured and up to the 50 ml. line on the tubes.

2. Fill the dropper provided with turbidity solution to the 0.5 ml mark on the dropper tube. Carefully compare the black dot at the bottom of each turbidity tube. The one at the bottom of the distilled-water tube should be very clear; the one at the bottom of the river-water tube should be fuzzier.

3. Constantly comparing the appearance of the black dots, empty droppers of this solution into the distilled water until the two dots are equally fuzzy. Stir the tube after adding each dropper's load. Note that you must ignore the color of the water. This will be frustrating at first, but you are concerned with the fuzziness of the dots, NOT the color of the samples! Note also that a "dropper-load" in this test refers to the dropper filled up to the 0.5 ml level noted on the tube!

4. To convert drops to Jackson Turbidity Units, multiply the number of dropper loads you put into distilled-water tube by 5.

QUESTIONS TO THINK ABOUT:

EFFECTS OF TOO MUCH TURBIDITY:

• Diversity of aquatic organisms declines
• Water gets warmer (check temperature)
• Dissolved Oxygen is lower if the temperature is raised
• Less light penetrates the river
• Photosynthesis is decreased
• Suspended solids clog fish gills, they may die
• River-bed habitats are filled in and destroyed

WHY IS THIS STUFF IN YOUR RIVER?

• Has there been much development lately?
• Are the river banks covered with vegetation?
• How eroded are the banks?
• Is there a gravel quarry upstream?
• If you live in a city, was the summer dry, followed by recent rains?
• Do ypu see any carp in the water?

*IS HIGH TURBIDITY A TEMPORARY PROBLEM? IF SO , WHAT CAUSED IT, AND WHAT DO YOU NEED TO DO NOW?

*Click here to return to the Water Quality Index Menu

*Click here to return to the NORP Main Menu