ABSTRACT

ABSTRACT: The navigation channel of the Mississippi River in the vicinity of the Head of Passes

(HOP) downstream of New Orleans is an area where significant dynamic shoaling occurs. During the

traditional high-water period in the spring, the shoaling in this area occurs rapidly and can represent a

hazard to deep-draft vessel traffic. The shoaling must be removed rapidly to maintain adequate channel

depth. Currently, dredging of the channel at HOP is conducted using hopper dredges, primarily due to

their mobility. Hydraulic dredges with conventional spudding systems and floating discharge pipelines,

such as cutterhead dredges, are considered a safety hazard in this area due to their inability to rapidly (and

consistently) move out of the way of vessel traffic. Unfortunately, hopper dredges simply move the

dredged material out of the channel and redeposit it in open-water disposal sites at the heads of Pass A

Loutre and South Pass. There are two disadvantages to this technique. First, the disposal sites periodically

become so filled with material that the hoppers cannot bottom dump dredged material at the sites. The

dredged material must be handled again at additional cost to provide sites for hopper disposal. Secondly,

there is no beneficial use of the dredged material. Hopper dredges can use direct pump-out to place

material beneficially in adjacent shallow open-water areas for marsh restoration, but this is considered

costly and has never been done before at the HOP.

This report presents the demonstration results of the dustpan dredge Beachbuilder using a flexible

discharge at the Head of Passes/Southwest Pass on the Mississippi River in June 2002. Dustpan dredges

equipped with a flexible-discharge floating hose and sufficient pumping capacity potentially have the

mobility required for safe passage of vessel traffic and can economically pump dredged material the

distances required for placement in a beneficial use scenario such as marsh construction. This report

details and discusses the project activities, operational characteristics of the Beachbuilder, and feasibility

of using a flexible-discharge dustpan dredge to augment the hydraulic dredging capabilities of the

U.S. Army Corps of Engineers on the Mississippi and other rivers. The goal of this report is to use the

project results to identify potential opportunities for reducing overall costs for channel maintenance and

increasing beneficial use of dredged materials during dredging Corps navigation projects.

DISCLAIMER: The contents of this report are not to be used for advertising, publication, or promotional purposes.

Citation of trade names does not constitute an official endorsement or approval of the use of such commercial products.

All product names and trademarks cited are the property of their respective owners. The findings of this report are not

to be construed as an official Department of the Army position unless so designated by other authorized documents.