Dredging Operations

General Dredging Information

The Dustpan Dredge is like a large vacuum cleaner. This type dredge is used on the Mississippi River. The suction head, approximately the width of the dredge, is lowered to the face of the material to be removed. High velocity water jets loosen the material which is then drawn by pump as a slurry through the dredge pipe and floating pipeline where the material is deposited outside of the navigation channel.

The cutterhead dredge is similar except for a rotating cutter which loosens the material to be pumped. This type of dredge is used for dredging tougher material that is found on the White River and harbors. Our dredging requirements are accomplished by both contract and government owned and operated dredges.

Dredging Mission

The largest dustpan dredge in North America, U.S. Army Corps of Engineers, Memphis District, uses the Hurley to remove sediment from within the navigation channels of the Mississippi River. Dustpan dredges are unique to the Mississippi River system and work to maintain a navigable channel for commercial navigation to move unimpeded.

The Hurley has a large suction head with high velocity water jets that loosen the silt and sand materials on the river bed and pump this material through a floating pipeline and is deposited outside the navigation channel near the riverbank.

Dredge Hurley

History

The Dredge Hurley was built in 1993 by Halter Marine in Moss Point, Mississippi for the USACE Memphis District. It was originally built to replace the 1933-built Dredge Burgess and designed to dredge to a maximum depth of 40 feet. Not long after entering service, the need to dredge deeper was realized.

A project to lengthen the dredge and increase its digging depth was authorized in 1997 and concept engineering was completed in 1999. In 2000, portions of the project were funded and completed. New azimuth bow thrusters and a new ladder hoist system were installed. The new A-frame and ladder hoist winch was sized for the eventual planned lengthening of the dredge and ladder.

Extreme high water in 2007 brought the need for a deep digging dredge was re-realized. Soon, the lengthening project was authorized and funded. In 2009, the ladder extension project began at Ensley Engineer Yard in Memphis. The ladder was lengthened by 48 feet to a total length of 108 feet. The vessel hull was also increased by 48 feet from 305 to 353 feet. This increased length allows the dredge Hurley to dredge up to 75 feet deep.

Dredge Hurley Videos

Dredge Hurley

Hurley DPIP    

The Dredge Hurley is the largest dustpan dredge in North America, coming in at 348.5 feet long and 58 feet wide. Its hull is 11 feet deep, and its draft is 7 feet. It is a self-propelled dredge and operates using anchor wires and its propellers. There is one dredge pump on board and it is powered by dual 1500HP electric motors. The Hurley has a 38-inch diameter suction pipe with a 32-inch diameter discharge pipe.