International Dredging Review

International Dredging Review

Dan Krumholz is the new president of the WEDA Midwest Chapter elected at the chapter meeting held November 27 through 29 at the Crowne Pointe Hotel in Detroit. Krumholz is with the St. Paul District Corps of Engineers and works from the Fountain City Wisconsin office.

Don Seibert of Southwind Construction is vice president/treasurer and Dave Schlenker of Bay West Inc. is secretary.

In December Krumholz announced that the chapter would meet on October 1 through 3 2002 in the Twin Cities Minnesota.

The meeting began with an ice breaker on November 27 hosted by Bean Environmental J.F. Brennan Ryba Marine Cable Arm Clamshell Faust Corporation and Luedtke Engineering.

On the 28th a technical program of 10 talks was presented. This included reports by Corps of Engineers representatives on dredging programs at the Dredging Research and Development Program (DOER) the Mississippi River and Tributaries and the Great Lakes and Ohio River Region.

Don Ellis of Geoturf Inc. spoke on a geotextile tube dewatering project in Elberta Michgan. Geotubes are a low tech approach to dewatering all sorts of solids he said. Using a polymer from AquaChem at 10 to 20 ppm they let the tubes sit one week or 10 days after filling after which the material could be hauled away.

He described the hanging bag test which lets you know which fabric works best. It is a low-tech method of assessing performance of a particular sludge he said. Hang the bag so effluent can be captured create a representative sample and add it to the bag. Geotube cost is $5 per cubic yard of dredged material. For larger jobs this is not the most cost effective approach but where there is limited space and 30000 to 40000 cy of material this approach is justified.

Geoturf has three locations and they keep a variety of sizes of tubes at each location as well as turbidity curtains silt fence and plastic sheets to lay under the tubes.

A roll of geotube 200 feet long weights approximately 1000 lbs and will need equipment to handle it said Ellis. You can unroll it manually but be sure to tie it down or it will roll away when it is filled.

Victoria Pebbles works on transportation and sustainable development issues for the Great Lakes Commission (GLC) and is a member of the Commission’s Dredging Team (the Great Lakes Dredging Team GLTD.) She explained that the GLC represents eight U.S. states and two Canadian provinces to promote orderly development of the water and natural resources of the Great Lakes basin and St. Lawrence Seaway. The Dredging Team was formed in 1996.

There are 130 Great Lakes harbors requiring four million cubic yards of maintenance dredging every year she explained. This material is placed in 40 confined disposal facilities (CDF’s) throughout the region and many have reached capacity and are being closed. The GLDT has made it a priority to research these sites and other alternatives. The group is working through Congress to expand the Corps of Engineers’ authority for beneficial use of dredged material under Section 204 of the Water Resources Development Act of 1992. Beneficial use is now limited to aquatic habitat protection and restoration.

One and a half million boats operate on the Great Lakes said Pebbles. The GLDT is looking at the economic impact of recreational boating to increase funding for recreational harbors. With a $20 million annual budget for maintenance dredging some harbors are still left high and dry she said.

The GLDT website is

Michael Cox of the Channel Maintenance section of the Rock Island District Corps of Engineers talked on Dredging Opportunities and Challenges Along the Upper Mississippi River. His job is to coordinate with customers resource agencies and other districts and divisions to identify ways to efficiently manage the river he said. There are 1200 miles of navigation channel in three districts in the Upper Mississippi and tributaries said Cox. Of the 5.5 million cubic yards of dredging done per year in this channel most is done in the St. Louis District mainly by the Corps dustpan Dredge Potter. The challenges are in defining the proper equipment and placement sties he said. Where there are small volumes it is not economical to mobilize hydraulic equipment and mechanical dredges are used in these areas.

He described methods being used to reduce dredging including notching existing dikes and building chevron dikes and bendway weirs. Micro modeling with simulated bedload sediment can model proposals for structures and is a very useful tool he said.
A problem they are working on now is maintenance and repair of tight bendways in the river which are dangerous for large barge tows. The district is looking to see what changes they can make in bank stabilization to avoid creation of tight bends.

He described several new technologies being used for dredging and dredged material management including the Eddy Pump used at Ballard’s Island back channel in Indiana DRE Technologies’ Dry Dredge used at Peoria Lake on the Illinois Waterway and the dewatering systems used by J.F. Brennan in Iowa. New technologies are described on the website

John Lally of Bean Environmental LLC described the New Bedford Harbor Superfund Site where the hybrid dredge Bonacavor performed a five-day test of a PCB-contaminated site while the impacts were monitored. Ninety-seven percent of the PCB mass was removed leaving 29 ppm after dredging was completed down from 857 ppm prior to dredging. In one area the level was down to 10 ppm. The dredging caused little impact on air and water quality.

He describerd a tour of dredging disposal technologies in Holland. He viewed a horizontal disc cutter developed by Boskalis with emphasis on low turbidity and accuracy especially cutting slopes.

He visited the Slufter a placement area for contaminated material in Rotterdam that has a 200 million cubic yard capacity. It has been in operation for 10 years.

Ray Bergeron described Environmental Bucket Projects in Saginaw Michigan and Massena New York He showed a film of the Saginaw River project which was performed using the WINOPS dredge positioning system for x and y and Cable Arm’s Clamvision for depth penetration and its bucket open/close indicator.

Lowering the bucket more than one foot per second will cause turbidity by creating downward pressure said Bergeron. A normal dredging cycle for contaminated material is three minutes he said. With the aid of the monitoring and positioning systems the Cable Arm bucket can dredge to an accuracy of plus or minus three inches he said.

At the Reynolds Metals plant at Massena New York in the St. Lawrence River Faust Corporation dredged 160 cells 50 by 50-feet each using a Cable Arm clamshell. The project was shown in real time on a website where dredging activity turbidity monitoring results and air quality results were posted through project completion in October.

Other companies involved in the project were construction manager Bechtel Corporation project engineers Metcalf and Eddy and upland disposal contractor Parris Excavating.

Eric Seagren spoke on Dredging Contaminated Sediments. He described the capabilities of a hydraulic dredge explaining that percent solids by weight a dredge can move is no greater than what exists on the bottom; no hydraulic dredge can consolidate material he said.

Ellicott Machine Corporation developed a new environmental dredge as a result of the New Bedford Superfund Site demonstration he said. The new swinging ladder dredge incorporates the first improvements to this type of dredge since the company built the first one in 1906 he said. It includes precise positioning by keeping three spuds down at all times moving forward while dredging is underway the ability to pump into a tanker truck where the driver can dial in the percent solids he needs.

Marty Wangenstein of Bay West Inc. described the Badger Superfund Site 60 miles north of Madison Wisconsin where ammunition had been manufactured from 1942 through 1975. It was contaminated with powdered activated carbon and aluminum from water treatment facilities. The 17-acre site was contaminated from two to seven feet thick with 87000 cubic yards of impacted sediments including copper lead mercury methyl mercury and ammonia.

The material was dredged using a 10-inch Mudcat MC-2000 and a 275 hp booster and pumped into geotubes where it was dewatered using gravity flow. The metals were removed from the water and the remaining water containing ammonia was sprayed on 43 acres of surrounding agricultural and grasslands and 55 acres of forest. The tubes were 36 feet in diameter and stacked three high.

The cost for dredging was $6 per cubic yard with a total of $2 million for the laydown area and geotubes. The dewatered material is not considered a hazardous waste. It will take several years for the laydown area to drain completely and it will then be capped with clean material.

Jim Clausner discussed the Corps of Engineers Dredging Research and Development program in which the Corps of Engineers evaluates systems for use in managing dredged material. They have evaluated 11 technologies and describe 90 more in a database which is posted on the following website:

He described the Silt Wing Excavator the flexible dustpan the telescoping weir and the seabed impeller leveling and trenching device. The flexible dustpan will be tested in South Pass in March 2002 by the New Orleans District he said.

Steve Jones of the Corps of Engineers Mississippi Valley Division described the division’s 2300 river miles which contains 54 lock and dam structures. The navigation channel requires 116 million cubic yards of dredging per year at an average cost of $120 million.

Tim Fudge described the Corps of Engineers dredging mission in the Great Lakes and Ohio River Division. On the Ohio River near Evansville Bend the community comes out every year to welcome the dredge for the annual maintenance dredging he said. There is a high recreational use of the river here with good community support.

He described dredging projects in the Louisville Huntington and Pittsburgh Districts on the Ohio River and tributaries such as the Cumberland and Monongahela Rivers.

Doug Zande of the Detroit District reported that the lake levels are down which has caused a need to watch the harbors and channels more closely and dredge them more often. Historically the budget is $16 to $17 million for dredging he said but because of the lake levels that has been increased by $8 million to $25 million. The number of harbors to be dredged increased and the cost rose he said. In FY01 they reprogrammed $6 million from the O&M budget for dredging. In FY02 they will reprogram $4 to dredging from the O&M budget.

Zande described the website for the Navigation Data Center where all dredging statistics and information for the Corps of Engineers are posted and updated monthly. The site is:

Jimmy Aidala former chapter president thanked everyone for coming to the meeting which had been changed at the last minute from October 3 which was considered too soon after the September 11 disaster.