Abstract
Saltwater intrusion is a pervasive threat to coastal ecosystems. Common management strategies entail the installment of engineered flow control structures, though there is a dearth of work on their prevalence across the landscape and how different structures impact salinity under various hydrologic conditions. We manually classified more than 900 structures with most either being culvert pipes or riser structures. We then investigated how these structures impacted salinity in surface waters after the landfall of Hurricane Florence in 2018 and during the Summer of 2020. To accomplish this, we combined longitudinal and depth surveys, with long-term monitoring of salinity up and downstream of three flow control structures. Our results reveal that a flow control structure’s ability to exclude or trap saltwater from/in upstream environments depends on its position inland and design. Engineered structures were effective at excluding saltwater, while unintentional structures sometimes trapped saltwater in upstream environments. This work sheds light on important factors land managers should consider when putting in place new structures for freshwater management purposes.
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Data Availability Statement
Some or all data, models, or code generated or used during the study are available in a repository online in accordance with funder data retention policies. Data will be made publicly available upon acceptance through Zenodo DOI: https://doi.org/10.5281/zenodo.7319870.
Acknowledgments
The authors have no known conflicts of interest. Many thanks to Emily Bernhardt for lending us her Cast Away CDT profiler. Thanks to Theo Jass for his field efforts in collecting and maintaining much of the data that went into developing this work. The funding of this work was provided by National Science Foundation (Nos. DEB 1427188, DEB-1713435, DEB-1713502, and EAR-1462169).
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Published In
Journal of Water Resources Planning and Management
Volume 149 • Issue 6 • June 2023
Copyright
© 2023 American Society of Civil Engineers.
History
Received: May 3, 2022
Accepted: Dec 21, 2022
Published online: Mar 21, 2023
Published in print: Jun 1, 2023
Discussion open until: Aug 21, 2023
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