Assessment of Estuarine Water Quality at Fort Pulaski National Monument: 2023 Data Summary

In July 2023, the Southeast Coast Network assessed water-quality at Fort Pulaski National Monument as part of the National Park Service Vital Signs Monitoring Program. Monitoring was conducted following methods developed by the Environmental Protection Agency (EPA) as part of the National Coastal Assessment Program (EPA 2014). Laboratory analysis measured chlorophyll a and total and dissolved concentrations of nitrogen and phosphorous. Field measurements included water temperature, pH, dissolved oxygen, and salinity. Water clarity, which requires a Secchi depth measurement, was calculated when possible. All measured parameters were rated as good, fair, or poor based on thresholds set by the EPA (2012). • Water clarity was rated good at twenty-eight sites (93.3%), fair at one site (3.3%) and poor at one site (3.3%). • Chlorophyll a concentrations were rated good at nine sites (30%) and fair at twenty-one sites (70%). • Dissolved inorganic nitrogen concentrations were good at eleven sites (37%) and fair at nineteen sites (63%). • Dissolved inorganic phosphorus concentrations were fair at all thirty sites (100%). • Dissolved oxygen concentrations (bottom) were rated good at eight sites (27%) and fair at twenty-two sites (73%). • A water-quality condition summary index was calculated for each site sampled at Fort Pulaski National Monument based on the categorical assessments of chlorophyll a, DIN and DIP concentrations, dissolved oxygen, and water clarity. This summary index indicated fair water-quality conditions at all thirty sites (100%). • See supplemental materials to compare the distribution of good, fair, and poor ratings for each parameter across the period of record. • Based on the EPA summary water-quality index rating, overall water-quality conditions at Fort Pulaski National Monument during 2023 sampling were fair. • The EPA summary water-quality index rating is consistent with findings 2014–2018.

Assessment of Estuarine Water Quality at Fort Pulaski National Monument: 2023 Data Summary

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