In July, Lemon Bay Conservancy volunteers marked the completion of our 12th year of water quality testing in the ponds and creek system at Lemon Creek Wildflower Preserve. Each month, conditions permitting, volunteers launch kayaks and collect water samples at 14 locations within 6 different freshwater ponds and 3 sites in the brackish waters of Lemon Creek.
At each location two bottles of water are collected according to protocols developed by the University of Florida/IFAS LakeWatch program. Water from one bottle is strained through a filter and stored in a desiccant container for later analysis by the LakeWatch team to determine the total chlorophyll level.
The second bottle will be used to measure levels of total phosphorous and total nitrogen. The samples are taken to a storage freezer at the Rotonda Community Center where they are periodically picked up by a LakeWatch staff member and taken to Gainesville for analysis at their lab. (You might wonder why we take the samples to Rotonda. Volunteers in Rotonda also use the LakeWatch protocols and have been collecting samples in the canal system there for more than 20 years! They allow our samples to be
stored for pickup along with theirs.)
At each location, in addition to the water samples, volunteers use a Secchi disk to take measurements of water clarity and pond depth. To measure clarity, the disk is lowered into the pond until it is no longer visible and the depth at which it disappears from view is recorded as the “vanishing point.” A review of Secchi disk readings over time helps in understanding changes in water clarity and provides a comparison to other ponds. Each year, the LakeWatch team provides summary reports that show trends in our water quality overtime.
There are significant differences among the various water bodies that we sample. We are seeing reductions of excess nutrients in several ponds, but not all of them. Reports for the creek locations do not show consistent patterns. We welcome new volunteers to join our water quality testing team, both to help log data on shore and to collect samples on the water.
If you’d like to get involved, please call the office at 941-830-8922, or send us a note at lbconservancy@comcast.net.