To document storm events that may induce a redistribution of sediment in the vicinity of the New York Bight 12-mile sewage sludge dumpsite, current meter moorings were deployed in water depths from 20 m (near the mouth of New York Harbor) to 53 m (within the Hudson Shelf Valley) from July 1986 through June 1989. Ten usable instrument records ranging from one month to one year in duration were obtained; eight of them near-bottom records. Seasonal and geographic variability of wind-induced flow were examined. The wind is most efficient in driving the subtidal currents in the 2--10 day frequency band during winter when the water column is well mixed and when the eastward component of the wind often induces and sustains an up-valley (northward) bottom flow. Maximum efficiency occurs for wind from 300¿ (WNW) and at sites located within the Hudson Shelf Valley. A continental shelf bottom boundary layer model (Glenn and Grant, 1987) was used to estimate resuspended sediment transport. Model inputs include bottom currents (observed), orbital wave velocities (estimated), and sediment grain size (from the literature). Model output indicates that sediment resuspension at the current meter sites occurs approximately 5% of the time, primarily during winter months. The difference in along-valley flux between two moorings provides a rough estimate (6-month time series) of deposition and erosion.

The net deposition (+0.02 mm) was no greater than the deposition and erosion resulting from individual storms. A three-dimensional circulation model (You et al., 1991) is applied to increase the spatial resolution of the near-bottom current field (4 km grid) for a storm event in May of 1987. Given these velocities that vary in space and time, the redistribution of sediment was modeled for different surface wave conditions. Areas of deposition aligned with the Hudson Shelf Valley due to less wave-induced resuspension in deeper waters. Given all the uncertainties in the input variables (grain size, surface waves) and the simplistic assumptions made in modeling the deposition and erosion, it is still uncertain how much sludge is permanently removed from the area, but episodic redistribution of surficial sediment evidently occurs throughout the Inner New York Bight. ¿ American Geophysical Union 1994