Previous Page 2 of 3 Next

Continued: Big river, big trouble: Dredges working overtime to open Mississippi

  • Article by: JIM ANDERSON , Star Tribune
  • Last update: August 5, 2014 - 9:12 AM

A vital link

Near Wabasha, just upriver from where the Goetz was dredging, the Big J.O. was among three towboats moored together. It’s one of 13 towboats owned by Yazoo River Towing Co. in Vicksburg, Miss., and the only one in the fleet that can’t go anywhere, said Patrick Smith, company president.

“It’s been a very big hit on us,” Smith said. “But I know the Corps of Engineers is working around the clock to clear up the channel. They do an amazing job.”

While the wait hasn’t been uncomfortable — modern towboats like the Big J.O., christened just this spring, have all the comforts, he added, including exercise rooms and computer access — the 10-member crew has been spending time getting the boat prepared for a fast and furious pace once traffic is moving again.

“That being said, there’s only so much cleaning you can do,” Smith added with a wistful chuckle.

It rains, and pours

This year’s shipping season was already off to a late start, with thick ice on Lake Pepin slow to melt. The traffic was just picking up when heavy rains began in April, and hit again in early June. As the rain fell, Mississippi tributaries, chiefly the Chippewa River in Wisconsin and the Zumbro in Minnesota, swelled and became a torrent, carrying with them tons of silt that tumbled quickly to the river bottom.

“I’d say it’s been a ragged year,” Nelson said.

More rain in late June was the final blow, with high water and fast currents forcing the Corps’ normal seasonal dredging operations off the river after they had barely gotten a start.

“That was the fourth high-water event of the year — it turned out to be a tough one,” said Jeff Hopkins, assistant master with the Corps of Engineers, helping supervise the crew that’s been working to clear a 9-foot navigational channel for barge traffic.

Along with the big Goetz, a smaller Corps dredge and several private contractors are working to unclog a portion of the river known as Pool 4, near Wabasha, which first closed on July 19; and a section near Winona called Pool 6, which closed July 23 after a towboat ran aground.

“Even if we can get the river open by [Friday], we’re not out of the woods,” said George Stringham, spokesman for the Corps in St. Paul. “There’s plenty of other places that need to be dredged, and dredged soon, or the river’s going to be closed again. This is going to be ongoing through the summer.”

Dredging is part of the annual maintenance routine for the Corps, but nothing like this year’s emergency operations, Hopkins added. His crew, many of whom are housed on the nearby Quarters Boat Taggatz, has been working in 12-hour shifts to clear the sandbars that formed when floodwaters quickly receded.

The dredging is a complicated process, he explained. Engineers first map the river bottom, then lay out a rectangular area called a “cut” for the 600-ton Goetz to eat into.

“People tend to think the sandbars are fairly evenly spread out, but they’re not,” Hopkins said. “It’s like sand dunes at the bottom.”

The varying depths are followed by Eric Carlson, leverman with the Corps, who controls the cutterhead with a joystick, guided by an array of computers acting as his underwater eyes. When it gets cranking, it can clear 2,000 cubic yards in an hour — more than 200 dump truck loads. Some of the sand is hauled off on barges, but most is piled on islands — stretching storage space in some areas. The Corps, Hopkins added, offers the sand for reuse.

The Corps has marching orders to maintain a 9-foot shipping channel, but the Goetz is going a little deeper — 12 feet — for good measure. “If we go a little deeper, hopefully we won’t have to be back here until next year,” Hopkins said.

While it works, the Goetz is held in position by a pair of huge stern vertical steel shafts called “spuds” — an improvement in technology on the old Dredge Thompson, retired two years after more than 65 years of river duty — that also nudge the boat forward by computer.

  • related content

  • Video: Minnesota’s river transport connection blocked by silt

    Tuesday August 5, 2014

    Crews are working 24 hours, 7 days a week to clear the Mississippi River of flood-related silt.

  • Photo gallery: River traffic in slow lane

    Monday August 4, 2014

    Barge and towboat traffic on the Upper Mississippi River is at a standstill after the navigation channel -- through...

  • Three dredges have been employed to remove sediment in the Upper Mississippi in an effort to restore service to the navigation channel.

  • The U.S. Army Corps of Engineers has been spearheading efforts to clear the river of silt before the buildup creates economic snags for shippers and consumers.

  • The cutter head of this dredge cuts a 200 foot swath into the navigation channel, insuring a 12-foot deep channel. The sand is dumped on the edge of the channel and will be removed later after safe navigation is restored. Barge and towboat traffic on the Upper Mississippi River is at a standstill after the navigation channel -- through which about half of the nation's grain exports pass -- became clogged with sediment from floodwaters this year, the same floodwaters that delayed the start of the shipping season by several weeks. The U.S. Army Corps...

  • Workers prepared to remove a section of sand transport pipe as the dredge closed in on the edge of the channel, where a 200-foot swath was created so as to ensure a 12-foot deep channel for safe shipping after the river reopens to barge and towboat traffic.

  • get related content delivered to your inbox

  • manage my email subscriptions


Connect with twitterConnect with facebookConnect with Google+Connect with PinterestConnect with PinterestConnect with RssfeedConnect with email newsletters