Dredged material may be carried away from the channel section by littoral and tidal currents. During the dredging process, the vessel travels along the entire length of the shoaled area casting material away from and beyond the channel prism. The sidecasting dredge picks up the bottom material through two dragarms and pumps it through a discharge pipe supported by a discharge boom. Dangerous and unpredictable conditions prevail in these shallow inlets making it difficult for conventional plant to operate except under rare ideal circumstances. The projects to which the sidecasters are assigned for the most part are at unstabilized, small inlets which serve the fishing and small-boat industries. The vessel is self-sustaining and can perform work in remote locations with a minimum of delay and service requirements. The dredging operations are controlled by steering the vessel on predetermined ranges through the project alignment. The discharge pipeline is suspended over the side of the hull by structural means and may be supported by either a crane or a truss-and-counterweight design. Instead of collecting the material in hoppers onboard the vessel, the side-casting dredge pumps the dredged material directly overboard through an elevated discharge boom thus, its shallow draft is unchanged as it constructs or maintains a channel. The hull design is similar to that of a hopper dredge however, sidecasting dredges do not usually have hopper bins. The sidecasting type of dredge is a shallow-draft seagoing vessel, especially designed to remove material from the bar channels of small coastal inlets.
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