Published Papers
An Earthen Sill As a Measure to Mitigate Salt Intrusion in Estuaries
Gijs G. Hendrickx, Laura A. Manuel, Stuart G. Pearson, Stefan G. J. Arninkhof, Ehab A. Meselhe
At a global scale, deltas are vital economic hubs, in part due to the combination of their access to inland regions via river systems with their proximity to sea. However, with the sea in close vicinity also comes the threat of freshwater contamination by saline seawater, especially during droughts. This study explores the potential of a mitigation measure to estuarine salt intrusion, namely the construction of a (temporary) earthen sill—a measure implemented in the Lower Mississippi River near New Orleans (LA, USA). This study suggests design guidelines on how a sill can be used to mitigate estuarine salt intrusion: the design should focus on the longitudinal placement and the height of the sill, and the mitigating efficiency of the sill reduces with increasing tidal range. Overall, a (temporary) sill has great potential to reduce salt intrusion in salt wedge estuaries if there is sufficient water depth available.
Hydrometeorological Drivers of the 2023 Louisiana Water Crisis
P. W. Miller, M. Hiatt
During summer and fall 2023, Louisiana experienced a historic local drought while dry conditions elsewhere in the central US withheld vital runoff from the Mississippi River, leading to below-normal discharge into the Gulf of Mexico. Thus, by late October 2023, Louisiana was gripped by two super-imposed water crises: a severe local drought and saltwater contamination in the Mississippi River channel. This study frames the development of the water emergency through the lens of flash drought using the Evaporative Demand Drought Index (EDDI). The EDDI shows south Louisiana experience a flash drought during June 2023, while the Mississippi River basin was subsequently characterized by large expanses of high-percentile EDDI in August-September 2023 shortly before the saltwater intrusion episode along the lower Mississippi River. Over the last 15 years, MRB-wide EDDI percentile has oscillated between years-long elevated and depressed states, accounting for 23.7% of the monthly discharge anomaly near New Orleans.