Secchi depth (clarity)
What is it? Secchi readings are an effective way to monitor water clarity in lakes and oceans, but not so helpful for shallow areas or streams.
Why is it important? Completely natural as well as man-made content 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
- Construction, dumping or pollution sites
What does it mean? Baseline testing is important as each body of water will have unique factors contributing to water clarity. Some very healthy lakes will have very low readings if they are naturally muddy or coloured. Recording in the same place over time will give you a more accurate picture of what is normal for your body of water.