A COMPARISON BETWEEN DREDGE INDUCED SEDIMENT RESUSPENSION AND THAT PRODUCED BY NATURAL STORM EVENTS

Abstract

Field observations indicate that the effect of dredge-induced resuspension on sediment transport within small estuaries is generally negligible in comparison to the transport induced by natural storm events. Data obtained in the Thames River, near New London, Connecticut show dredge-induced resuspension to be essentially a near field phenomenon. The resultant plume of material increases total suspended load in the river by approximately 25% but extends over less than 2.5% of the total estuarine area. In contrast storms are observed to increase total suspended load by a factor of three, influencing concentration levels throughout the estuary. These factors, in combination with the lower frequency of dredging vis-a-vis significant storm events, appear to effectively limit the influence of dredge-induced resuspension.