Corps’ oldest dredge still going strong after 83 years

Dredge Potter assists with emergency repairs at Lock and Dam 25
in Winfield, Missouri, Nov. 25, 2014. After engineers discovered
erosion along the overflow dike at Lock and Dam 25 the Dredge
Potter was brought in to assist in repairs before flooding could
threaten the stability of the dike.

The Corps oldest dredge wrapped up another successful dredging season on the Middle Mississippi, January 8.

The U.S. Army Corps of Engineers St. Louis District’s Dredge Potter, built in 1932 during the Great Depression did not let age stand in her way as she moved more than 3.2 million cubic yards of sediment this year – enough to cover a football field to a height of 1,500 feet.

The Potter and her crew of 50 began work on the muddy Mississippi River, August 1 aiding the St. Louis District in achieving its mission of maintaining a Congressionally-mandated 9-foot deep, 300-foot wide navigation channel.

Within the St. Louis District, dredging is performed on 300-miles of the Mississippi River, from Cairo up to just below Hannibal, Missouri, as well as 80 miles of the Illinois River and 36 miles of the Kaskaskia River.

The 240-foot long, 46-foot wide dustpan Dredge Potter was originally a steam-powered paddlewheel before her transformation to a more modern diesel-electric power in 2001.

“Dustpan dredges are very efficient on the main stem of the Mississippi River. They can move easily in and out of traffic, and were specifically designed to move the sand that’s in the Mississippi River,” Lance Engle, dredging project manager with the St. Louis District said.

New Capabilities

Spill barge Thomas N. George places dredge materials from the
Mississippi River to fill eroded areas near Lock 25 in
Winfield, Missouri. U.S. Army Corps of Engineers
St. Louis District officials used the Dredge Potter’s flexible
pipe assembly to move more than 100,000 cubic yards to
stabilize the overflow dike.

Bearing the name, Thomas N. George, a new spill barge joined the Potter for its inaugural season this year.

Named after the late Thomas George, former master of the Dredge Potter, the specialized spill barge uses a flexible floating dredge pipeline with the Corps’ dustpan dredge.

Using the floating flexible pipe allows the Dredge Potter more material placement options than using a traditional rigid metal pipe which requires left or right side-casting of the dredged material.

The flexible floating pipe allows the dredged material to be placed independently of the dredge as it moves to avoid fleeting areas and or for more versatility around well-used areas of the river.

November was a busy month

While nearly finished at the mouth of the Kaskaskia River, November 14, the Dredge Potter experienced a D-ring failure (a critical link in the suction ladder lifting chains). When the D-ring failed the Dredge Potter’s suction ladder dropped and became stuck nearly vertical under the dredge. The Potter’s crew worked tirelessly and five days later the ladder was recovered and secured without any additional damage.

Dredge Master Randy Jowers, St. Louis District Service Base staff and Marine Design Center developed an interim repair, and the Potter was back to work status by November 22, just in time to face another crisis on the river.

When engineers discovered erosion along the overflow dike at Lock and Dam 25 in Winfield, Missouri, the Dredge Potter and her crew answered the call. With no contract or government dredges available, the Potter was willing and available to assist with the emergency repairs before flooding could threaten the stability of the dike. If flooding causes the dike to fail, barge traffic on the river could come to a standstill.

With repairs to the ladder rigging complete the Potter and her crew immediately departed for Lock and Dam 25, November 22.

By November 23, the Potter had reached her destination. Upon arrival her crew began the process of setting up the 2,400-foot flexible pipeline. The flex pipe coupled with the spill barge gives the dredge team the ability to reach farther and aim more precisely when placing material. Two days later, the Potter was already placing material into the scour hole below the Lock 25 spillway. 258,000 cubic yards of dredge material was placed into the scour hole and in an adjacent stockpile.

"Without the flexible dredge pipe and the spill barge Thomas N. George, our only other option would have been dredging by mechanical means with a clamshell dredge," said Mike Rodgers, project manager for the emergency repairs at Lock and Dam 25.

The clamshell method would have moved roughly 2,000 cubic yards of material a day, with an estimated timeline of nearly three months to complete. Employing the Thomas N. George and flex pipe, the Dredge Potter team moved more than 20,000 cubic yards a day, completing the work in about ten days.

"With the flex pipe and the Thomas N. George spill barge, we have a lot more options to place of material," Rodgers said.  "Without it, we wouldn't have completed the permanent repair in time for the spring flood season."

Hardest working octogenarian on the river

For more than 80 years the Potter has remained true to her mission, making navigation possible for towboats to move commodities up and down the Mississippi.

St. Louis is the third largest inland port by tonnage, and commercial navigation thrives on the St. Louis District’s stretch of the river thanks in large part to the hard work of the Potter crew.

Operating 24 hours a day, the crew is organized into three watches, with two alternating watches while the third is off duty. There is one First Mate, three Second Mates and four Deckhands on watch at all times.

“If it were not for the dedicated Potter crew and Service Base staff, the Dredge Potter could have easily been down for repairs for a month, which would have been disastrous to maintaining the navigation channel and supporting the emergency scour repair at Lock 25 spillway,” said Engle.

A typical dredging season in St. Louis District runs from July to December, but can change based on river conditions. As recently as the 2012-2013 dredging season, more than 8 million cubic yards of sediment was dredged in a six month period to address low water conditions.

Corps' officials meet with Illinois leaders to discuss low water operations

Leaders discuss current and future actions the Corps will take to
 maintain a safe and reliable navigation channel during low water.

The U.S. Army Corps of Engineers Mississippi Valley Division Commander Maj. Gen John Peabody and St. Louis District Commander Col. Chris Hall met with state and local representatives yesterday in Alton, Ill., to discuss current and future actions the Corps will take to maintain a safe and reliable navigation channel during low water.

The meeting, which was led by Sen. Dick Durbin (D-Ill.), was also attended by Capt. Byron Black, U.S. Coast Guard commander of the Upper Mississippi River Sector, Rep. Jerry Costello (D-Ill.), Rep. John Shimkus (R-Ill.), Lt. Gov. Sheila Simon (D-Ill.) and river industry representatives.

"We've been preparing for this since early summer, which means continuous collaboration with our partners the U.S. Coast Guard and the navigation industry to help provide a safe and reliable channel on the greatest, navigable watershed in the world," Peabody said.

Peabody explained the removal of 890 cubic yards of limestone that began this week near Thebes, Ill., is just one phase of the action the Corps is taking to improve the navigation channel for the river industry. With the removal of the rock, Peabody said, the Corps' expects that restrictions on barges will not be necessary at this time.

"We remain cautiously optimistic that if we do have any interruptions, it will be short in duration as we continue to maintain a safe and reliable navigation channel," Peabody said.

The Corps also began increasing releases from Carlyle Lake December 15 to help provide the depth necessary for river commerce to pass Thebes before the rocks can be removed. The full extent of the releases is expected to reach Thebes by Dec. 24. This will provide an additional six inches of depth in this critical reach of the river. Releases will continue if needed until the river level increases through precipitation, or until Carlyle Lake reaches its winter pool elevation. With the additional release schedule, Carlyle Lake is expected to reach its winter pool level in approximately three weeks.

Peabody said the Corps is also looking at the possibility of additional releases from other reservoirs, if that becomes necessary.

During the meeting, Hall explained the dredging actions the Corps is undertaking and plans to continue through the low water. "The U.S. Army Dredge Potter has dredged more than 6 million cubic yards of material on the Upper and Lower Mississippi since it began operations in June."

"We will continue dredging problem areas, conducting channel patrols and surveys to keep commerce safely moving on the Middle Mississippi," Hall said.

For more information, visit www.mvs.usace.army.mil/lowwater. 

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UPDATE – Rock removal work underway on Middle Mississippi

The removal of 890 cubic yards of limestone from the
navigation channel on the Mississippi River near Thebes, Ill.
(Photo by U.S. Coast Guard)

The U.S. Army Corps of Engineers St. Louis District rock removal work is underway on the Mississippi River near Thebes, Ill.

Work began Saturday, Dec. 15, upstream of the Thebes railroad bridge. Low water on the river has allowed rock removal to be accomplished using excavating equipment. The progress of the excavation reduces the need for marine blasting, although that remains one of the options for permanently improving the channel for low water periods.

The U.S. Coast Guard is coordinating notices to mariners, and river closures are in effect for 16 hours on working days between 6 a.m. and 10 p.m. each day during the rock removal, with traffic allowed to pass for eight hours.

The work will remove around 890 cubic yards of limestone from the water-starved river to reduce the risk for vessels in the channel during low water. The rocks are part of a large formation that impedes the navigation channel during low water. More rock removal is planned for later dates, but the work beginning Saturday will address areas that will have the most immediate impact on the navigation.

Removing the rock formations are one of many operations the Corps and U.S. Coast Guard are undertaking along the narrowing river to maintain a 9-foot deep channel for river navigation. Dredging has been ongoing since early July to preserve the channel, as well as continued surveys, channel patrols to keep commerce safely moving on the Middle Mississippi.

The Corps is in constant communication and coordination with the Coast Guard and the river industry as the drought has reduced water levels throughout the Mississippi River Basin to historic lows.

The Corps of Engineers is working with the Fish and Wildlife Service and the Missouri Department of Conservation to avoid and minimize impacts to the environment. The focus by both the Corps and the Coast Guard, Hall said, is safety during the operation. The Coast Guard has established a safety zone for the affected sections of the river. The safety zone will prohibit access to the river and affected areas along the banks on both sides of the blasting sites.  Safe public access to the work area is limited. Coast Guard, Corps and local safety officials remind anyone planning to be in the area to be aware of posted signage and respect private property.

Coast Guard, Corps and local safety officials remind anyone planning to be in the area to be aware of posted signage and respect private property. Be aware that places newly revealed by low water are unstable.  Signage and other warning notices may not be immediately visible since many were placed when the river was at a higher stage.  Approaching the water at any time should include a life vest.  When in doubt, don’t go out.

For more information, visit www.mvs.usace.army.mil/lowwater. 

Follow us on Facebook: www.facebook.com/teamsaintlouis and Twitter: @Teamsaintlouis.

Corps releasing additional water from Carlyle Lake to aid Mississippi River traffic

Carlyle Lake is a multipurpose project located along the
Kaskaskia River in Southern Illinois providing flood damage
reduction, recreation, water supply, downstream navigation
and fish and wildlife conservation.

The U.S. Army Corps of Engineers St. Louis District began increasing releases from Carlyle Lake yesterday in support of safe navigation on the Mississippi River. 

Water from the lake will help provide the depth necessary for river commerce to pass Thebes, Ill., where rock formations pose a risk to navigation at -5 feet and below on the St. Louis gage. Carlyle Lake is located on the Kaskaskia River system in Southwest Illinois.

Carlyle Lake is one of few Corps reservoirs able to significantly capture water above its seasonal pool level to support navigation during the current drought. Maj. Gen John Peabody, Mississippi Valley Division commander, authorized all the lakes on the Upper Mississippi River system to hold an additional 10 percent above seasonal pool levels October 17 in anticipation of historic low levels on the Middle Mississippi.

Releases from Carlyle Lake began late Saturday, and will increase gradually to 4,000 cubic feet per second by Monday afternoon. The full extent of the releases is expected to reach Thebes by Dec. 24. This will provide an additional six inches of depth in this critical reach of the river. Releases will continue if needed until the river level increases through precipitation, or until Carlyle Lake reaches its winter pool elevation. With the additional release schedule, Carlyle Lake is expected to reach its winter pool level in approximately three weeks.

“With the Mississippi River watershed receiving less rain than forecasted, we are working to provide the water depth needed at a time when inches make a difference,” Peabody said. “We’ll continue to work closely with the navigation industry and our partners in the U.S. Coast Guard to keep the vital artery for commerce open.”

The releases are one of many measures the Corps and the U.S. Coast Guard are using in coordination with river industry to keep commerce moving during the drought. Additional measures include removing rock along the riverbed near Thebes, which is expected to begin this week. This work will provide a permanent improvement to the Middle Mississippi and will reduce risk to river traffic in low water. Additionally, dredging has been ongoing since early July, with the U.S. Army Dredge Potter moving more than 6 million cubic yards of sediment out of the navigation channel.

For more information, visit www.mvs.usace.army.mil/lowwater.  

Corps of Engineers to remove rock from Mississippi River channel

U.S. Army Corps of Engineers, Dredge Potter, dredging
 a section of the Upper Mississippi River, south of the
St. Louis Harbor.

The U.S. Army Corps of Engineers announced today the schedule for removing rock formations in the Mississippi River near Thebes, Ill., that pose a threat to navigation as water levels on the river drop.

The agency has awarded two contracts for rock removal work in a nearly six mile stretch of river. Newt Marine, Inc., of Dubuque, Iowa, will remove the rock formation upstream of Thebes; Kokosing Construction, from Fredericktown, Ohio, will remove the rock formation downstream of Thebes.

Work begins Saturday, Dec. 15, upstream of the Thebes railroad bridge. While final blasting plans are still being developed, full operations will begin early next week, with blasting to take place during daylight hours.  The U.S. Coast Guard is coordinating notices to mariners, and river closures are scheduled for 16 hours on working days starting Monday, Dec. 17, between 6 a.m. and 10 p.m. each day during the rock removal, with traffic allowed to pass for eight hours.

The work will remove around 890 cubic yards of limestone from the water-starved river to reduce the risk for vessels in the channel during low water. The rocks are part of a large formation that impedes the navigation channel during low water. More rock removal is planned for later dates, but the work beginning Saturday will address areas that will have the most immediate impact on the navigation.

Removing the rock formations are one of many operations the Corps and U.S. Coast Guard are undertaking along the narrowing river to maintain a 9-foot deep channel for river navigation. Dredging has been ongoing since early July to preserve the channel, as well as continued surveys, channel patrols to keep commerce safely moving on the Middle Mississippi.

“The drought across much of the Midwest is making river navigation challenging,” said Col. Chris Hall, St. Louis District commander. “We are taking additional measures and are confident that we will be able to maintain a safe and reliable channel for our partners in the river industry.”

The Corps is in constant communication and coordination with the Coast Guard and the river industry as the drought has reduced water levels throughout the Mississippi River Basin to historic lows.

The Corps of Engineers is working with the Fish and Wildlife Service and the Missouri Department of Conservation to avoid and minimize impacts to the environment. The focus by both the Corps and the Coast Guard, Hall said, is safety during the operation. The Coast Guard has established a safety zone for the affected sections of the river. The safety zone will prohibit access to the river and affected areas along the banks on both sides of the blasting sites.  Safe public access to the work area is limited. Coast Guard, Corps and local safety officials remind anyone planning to be in the area to be aware of posted signage and respect private property.

Coast Guard, Corps and local safety officials remind anyone planning to be in the area to be aware of posted signage and respect private property. Be aware that places newly revealed by low water are unstable.  Signage and other warning notices may not be immediately visible since many were placed when the river was at a higher stage.  Approaching the water at any time should include a life vest.  When in doubt, don’t go out.

For more information, visit www.mvs.usace.army.mil/lowwater. 

St. Louis Army Corps of Engineers gathering public input for River Training Structure assessment

Chevrons are a type of river training structure designed as a
blunt nosed, arch shape. (U.S. Army Corps of Engineers photo)

The St. Louis District U.S. Army Corps of Engineers will host two open house events to provide background information and get public feedback on the scope of an Environmental Assessment of New River Training Structures on the Middle Mississippi River.

The two open house events in Alton, IL, and Cape Girardeau, MO, will feature a brief overview of the Corps of Engineers’ river engineering mission, and information stations on River Training Structures with subject matter experts available to answer questions and get public input on what information should be considered in the assessment.

Tuesday, Feb. 7

6pm-8pm

National Great Rivers Museum - Classroom

#2 Locks and Dam Way, Alton, IL  62002

Thursday, Feb. 9

6pm-8pm

Cape Girardeau Nature Center - Multipurpose room

2289 County Park Drive

Cape Girardeau, MO  63701

River Training Structures are one of the ways the Corps of Engineers ensures America’s inland waterways are navigable for commerce, along with locks and dams, dredging, and revetments.

The St. Louis District is preparing an Environmental Assessment of new River Training Structures on the Middle Mississippi River (River Miles 195-0). Environmental Assessments are prepared in accord with the National Environmental Policy Act (NEPA) to determine the environmental effects of a proposed action. The assessment will determine if there are substantial and relevant considerations or data regarding construction of new River Training Structures that the Corps has not considered to date, and if further study is needed. River construction activities will continue during the Environmental Assessment process.

Public comments may be submitted in person at the open house events or may be submitted electronically to RiverTrainingStructures@usace.army.mil. Information on River Training Structures and the Corps’ navigation mission can be found at the St. Louis District River Engineering web site: http://www.mvs.usace.army.mil/arec/riverengineering.html

Teaching an old dredge new tricks: Army’s oldest dredge creates new habitat

Flexible dredge pipe connects to the USACE Dredge Potter.

(Photo by U.S. Army Corps of Engineers - St. Louis District)

The endangered Least Tern may have a new island to call home on the Mississippi River thanks to the U.S. Army Corps of Engineers - St. Louis District, the Dredge Potter and a flexible, floating dredge pipe.

Historically, the Least Tern nested on sandbars along the Mississippi River. The establishment of navigational pools, repeated flooding and an increase in recreational activities along the river has led to the decline of the population. 

As part of a pilot project during this year’s dredging season, the St. Louis District reused dredged material to build small islands using a flexible floating dredge pipe. 

“The flexible floating dredge pipe provides the St. Louis District opportunities to create a diversity of aquatic habitats such as sand islands and shallow water habitats in areas where it may not be possible without the use of dredged material,” Brian Johnson, biologist with the St. Louis District said.   

Each year dredging is performed on the Mississippi River in order to keep it open to the Congressionally-mandated depth for river traffic. Historically, dredged material placement locations and options have been limited by both equipment constraints and cost.  

When feasible, dredged material is recycled for beneficial uses within the river. Reuse is the preferred approach by the Corps of Engineers, and the St. Louis District is always seeking out innovative and creative ways to accomplish this task. 

“Our partners and stakeholders have challenged us to find more ways to reuse dredged material in an environmentally friendly way,” Johnson said. 

USACE Dredge Potter crew assembles flexible dredge pipe.

(Photo by U.S. Army Corps of Engineers - St. Louis District)

The Potter crew spent most of the off season prepping the dredge for the use of the flexible floating dredge pipe.

“It took a lot of planning ahead and creative ideas to make this happen,” Lance Engle dredge manager with the St. Louis District said.

Traditionally, the use of standard dredging practices limited the opportunity to reuse dredged material as sandbar or island habitat because of the physical limits of the rigid metal disposal pipe that is used.  

“Normally dredged material is side-cast along the main channel border in a linear fashion, resulting in a long, narrow disposal bar that is limited in size, elevation, and location,” Engle explained.

A St. Louis District experiment with flexible floating dredge pipe in 2005 led to the idea of using it to create islands and sandbars on the Middle Mississippi River. Demonstration projects by the New Orleans and Mobile Districts helped develop the idea and prepare the dredge crew for the new challenge.

Flexible dredge pipe helps create more diverse habitats.
(Photo by U.S. Army Corps of Engineers - St. Louis District)

The pipe’s flexibility allows the Dredge Potter to place dredged material in a specific location as it moves. This allows material to build up to create sandbars and island habitats in various shapes, sizes and elevations in the Middle Mississippi River while maintaining the navigation channel. 

These types of habitats are essential for the nesting and spawning of various fish and wildlife species such as the Least Tern.  

“The new method allows creation of more diverse environments for wildlife than traditional dredging methods,” Johnson added.  “These islands are often remote, providing protection from predators, boats and humans.” 

The flexible floating dredge pipe allows the St. Louis District to keep the river safe and open for navigation in an environmentally sensitive way.

“In the future, we hope this will be the way we do business,” Johnson said. “Eventually we hope to use the Dredge Potter not only for navigational purposes but for environmental management purposes as well.”