1. INTRODUCTION

The following paragraphs present methods for estimating sedimentation in dredging channels and harbor basins. Emphasis is placed on the methods used to compute the sedimentation that results in a need for maintenance dredging. Methods and dredging equipment necessary to accomplish maintenance dredging can be found in other references (e.g., Herbich, 1992). The methods discussed below have been used extensively by the authors for projects throughout the world. Recent important applications have been made for New York Harbor (Moffatt & Nichol Engineers, 1996; Moffatt & Nichol Engineers, 1998a), Colombia South America (Moffatt & Nichol Engineers, 1996) and Thailand (Moffatt & Nichol Engineers, 1998b). The methods have also been used in connection with subchannel placement cells for contaminated dredged material (Headland and Kotulak, 1999).

It should be noted that there are numerous more sophisticated numerical models for sedimentation in channels and harbors. Examples include two-dimensional (horizontal) models such as MIKE-21, which is a finite-difference model (Danish Hydraulics Institute, 1999) and the SED2D finite-element model (Araithurai and Krone, 1977), which is part of the FAST-TABS numerical modeling system. These models have been used extensively by the authors and example applications are presented at the end of this section. The following paragraphs, however, focus on the application of simpler analytical models. These models can be easily applied to practical problems and have the advantage of being...