Exhibiting the cumulative strength of its vast organization, two Bollinger shipyards teamed on an innovative project to increase the dredging depth of the Pine Bluff Sand and Gravel Co.
dustpan dredge, Wallace McGeorge
, from 62-ft. to 75-ft., enabling it to dredge at higher river stages and dispatch sooner on a falling river. To complete the task, Bollinger Quick Repair, Harvey, La., fabricated and installed 45-ton, 36- by 20-ft., port and starboard sections to the horn of the dredge, increasing the vessel's overall length from 252.5 to 288.5 ft. The shipyard then installed a new 46-ton, 40-ft. wide by 15- by 30-ft. high, A-frame which it had pre-fabricated for the dredge. The A-frame, which more closely resembles an inverted "U", is used to accommodate a new "ladder" that was fabricated at Bollinger Gulf Repair, New Orleans and installed at Bollinger Quick Repair.
"By assigning the work to two of our shipyards, we were able to complete the entire job in just over three months," said Allen Stein
, operations manager of Bollinger. The 120-ft. long by 17-ft. wide, 93-ton ladder is fitted between the legs of the A-frame and the two new hull sections so it can be raised or lowered to the required dredging depth. The 20-ton, 30.25-ft. wide dustpan suction head tips the lower "business" end of the ladder. The dustpan, which can be likened to a vacuum cleaner, is very efficient in excavating sand material from river bottoms. When the suction head is lowered to the river bottom, high velocity water jets on the suction head loosen the material, which is then drawn up by a single hull pump and transported through a floating pipeline mounted on pontoons and deposited outside navigation channels.
An EMD 20-645-E4-diesel engine powers the pumping and suction systems
and the boat's propulsion is supplied by two Caterpillar (CAT)
3516 diesels driving through Ulstein Z-drive units. Ducote Engineering Associates, Inc. of Jefferson, La. provided design and engineering services for the project. The Wallace McGeorge is under contract with the U. S. Army Corps
of Engineers (USACE), Memphis District, to help maintain Mississippi River deep
draft crossings between Baton Rouge and the Gulf of Mexico. According to Joaquin Mujica, USACE operations manager for South Louisiana ports, this area includes the largest U.S. ports based upon tonnage.
Mujica said the modified Wallace McGeorge will
give the USACE a "bigger stick", meaning deeper dredging capacity. He said dustpan dredges are more advantageous than cutterhead dredges in certain applications as they are self-propelled making them more mobile. He added that dustpan dredges are more economical than cutterheads for deep draft channel crossings.
Mark Lemoine of Pine Bluff's Alexandria, La. office said Brown and Root built the Wallace McGeorge, whose original name was Carl Burkhardt, in 1965 as a cutterhead dredge. Around 1980, it was converted to a dustpan dredge and renamed Lenel Bean by Bean Dredging, who had acquired the vessel. In 1991, Pine Bluff bought
the vessel and later renamed it Wallace McGeorge, for a member of the company's second generation of owners.