Clarity

How depth is measured

Lower your disk into the water until you can't see it any longer. Make sure you take note of how much rope you've lowered into the water.

What it means

Completely natural and man-made things can affect water clarity. Be sure to note if you've had a recent rainfall or if you've noticed unusual events near the test site. Your water clarity can be affected by:

• A recent rainfall that has stirred up the bottom
• How much sediment is suspended
• Algae blooms
• Natural mixing
• Dumping or pollution sites

How the secchi disk works.