Plain Language Summary

Turbidity is a widely accepted proxy for suspended sediment concentration and an important factor for contaminant transport and water quality. Here we show that turbidity depends on river discharge in long-term observations at multiple locations in an estuary. Such relationships are often used in rivers, but have not been commonly used in estuaries and tidal rivers, where tides and salinity also contribute to variability. Turbidity in the freshwater tidal region was more sensitive to discharge than in the saline estuary. Massive inputs of sediment due to extreme precipitation and flooding in 2011 resulted in increased sediment availability in the tidal river over multiple years. Turbidity throughout the tidal river was elevated for 2 years following the events, but changes were not apparent in the saline estuary. The observations provide guidance on recovery time scales for estuaries and tidal rivers to event-driven sediment inputs, which affects the delivery of material from the watershed to the coastal ocean as well as other impacts on water clarity.

About this article

This open access article, published Geophysical Research Letters in 2020, is based on research conducted in collaboration with the Hudson River National Estuarine Research Reserve. The article uses turbidity observations to characterize estuary response following extreme discharge such as from storm-related flooding, which can be a proxy for sediment release from dam removals.