From The Blog
Understanding the Water Quality in Kiawah Island Ponds
KICA’s Lakes Management Department maintains the health of the island’s 122 stormwater ponds. The ponds are designed to pass water through KICA’s drainage system and off of Kiawah Island. However, they are also an amenity for members, making it a great place to bird watch, fish with the family, or simply enjoy the outdoors. Lakes Supervisor Matt Hill described the process of managing the ponds as “finding a balance between a natural and aesthetically-pleasing value.”
On a daily basis, the ponds receive golf course and road run-off in addition to rainwater and tidal flows. These factors mean that nothing can be taken for granted and the department keeps that in mind. Since 1987, the department has monitored water quality with in-house testing. Early records indicate testing was a little less frequent than it is now, but the department currently tests 26 island ponds each week. They use these results to compare a number of parameters throughout the year, responding to ponds based on their data history.
How KICA Tests Water Quality in Ponds
The KICA Lakes Management team uses a YSI multiparameter water quality monitoring sonde. The device enables them to take a sample and receive a reading on temperature, conductivity, salinity, depth, and pH dissolved oxygen. Later, the team downloads the data and adds it to a spreadsheet with information dating back to 1987. The sheet allows them to track trends and identify changes in the pond over time. The department also contracts South Carolina’s Department of Natural Resources (DNR) to perform monthly (in the cooler months) and bi-monthly (in the warmer months) testing for algae and phytoplankton in the water. Twice a year, they also test for bacteria. These readings help the department monitor for algal growth, which can be harmful if large quantities bloom. If DNR reports abnormal algal growth, the department makes a point to spray the pond for a short-term solution, while considering if a larger, long-term solution is needed. A few years ago, algae became a problem in Ocean Park, which led the team to apply Phoslok that reduced the need for herbicides to an eighth of what was previously used.
Water quality testing is a tool to see a snapshot of what is going on in the water and the trends in each individual pond. If a parameter reading changes in a way that’s out of the ordinary, that tells the team something about the pond. This allows Matt and the Lakes Management team to be ahead of potential algal or undesirable vegetation growth.
Taking a Closer Look at the Stormwater Ponds on Kiawah Island
There are many exterior factors that become interior, including fertilizer, waste, and stormwater, when it runs off into the pond system. The ponds are home to many living things, including alligators, fish and wading birds, so they are always changing. In the mornings when the CO2 levels tend to be higher, the ponds tend to be more acidic. The temperature of the water in ponds has a direct impact on oxygen levels (warmer water holds less oxygen than cooler water) which can result in fish kills. The combination of KICA’s in-house testing and DNR’s testing enables the team to be ahead of potential problems.
With more than 30 years of pond management practices, the KICA Lakes Management department stays busy, especially in the summer months, to maintain the beauty and functionality of the stormwater ponds. Matt and his team of experts are making daily management decisions to improve the health of the ponds, so members and visitors of Kiawah Island can relax and enjoy the wildlife and beauty that Kiawah Island offers.