Photo: Richard Covey, Audubon South Carolina
Science

Hydrology

For over 37 years now, we have been collecting water samples from five locations (two more locations added in the last few years to accommodate sanctuary expansion) and running a simple battery of chemistry tests (pH, Dissolved Oxygen, Hardness, Nitrates, Nitrites, Phosphates, Turbidity). Our biggest concern for water pollution is non-point source agricultural runoff. Although we do not have the wherewithal to test for specific pesticides or herbicides, we can test for things like Nitrates, Nitrites, and Phosphates that are found in Agrichemicals. The assumption can be made, that if we are NOT having unusual levels of these things, then we are probably NOT having an issue with agrichemicals. Additionally, pH and DO can also be good indicators of other types of pollution or negative changes in water quality, while Turbidity can be indicative of siltation issues. Our theory is that if we can understand and continue to monitor what is normal for Four Holes Swamp, the better we will be able to identify the abnormal situation, and mitigate the problem.

An example… several years ago, the Mims Lake samples showed a huge spike in Nitrate levels. We discovered that the MacDougal Correctional Center’s ground application sewage treatment spray field had a breach in its berm. Sewage tainted water was trickling out of the field and into a secondary stream that flowed about 200 meters straight into the swamp about 200 meters upstream from the sample site. We were able to identify the problem and get the State to fix it. Problem solved!

Once again, our data has not strayed significantly from the baseline year, intimating that our water quality has stayed high.