Port #26: The BIG BANG !!!!

Great Loop II Date: 9/25/2014

Day # 56 (Thursday): 110 miles (1520 total miles)

Locks: 0 (10 total locks)

Port #26: Cape Girardeau, MO

UnTide, Infinite Sea and Ocean Breeze all elected an early morning departure so we could have plenty of daylight to get to our first anchorage, Little Diversion River south of Cape Girardeau, MO..  Untide lead the pack of three.  OB took the middle of the grouping and Infinite Sea pulled up the rear.  Untide traveled a few MPH faster.  They were still in VHF radio range however OB and Infinite Sea were staying together and well behind at about the same speed.

A beautiful sunrise on a calm and cloudless morning.

We saw many eddies and swirls from the weir dams under the water.

Limestone outcroppings were more frequent.  The eddies and swirls continued from the weir dams.  Some caused big whirlpools in the water that we had to avoid.  

The day unfolded perfectly with sunny skies and no fog.  We still had quite a few oncoming tows to navigate around.  We were having a fine time, dodging some logs along the way, working our passes out with the tow captains and keeping our distance from the ever present swirling waters moving over the weir dams.  Although the Mississippi had just receded from flood stage, it quickly went back to below normal pool.  We had not noticed it being low water, but the tow captains had mentioned it in their conversations.

Debris left behind from the earlier flooding.  Look closely...there's a red nun buoy on the left and a green can buoy on the right in the middle of the debris!

We passed this huge quarrying operation.  Notice the water...

Todd was worried one of these machines might fall from the precipice of the quarry.

Loading limestone into the barges.

Tow ready and waiting for loaded barges to be readied for transport.

More limestone outcroppings.

The Kaskaskia River Lock and Dam.  Some Loopers opt to stay here tied off the lock wall.

We passed by Chester, IL, the birthplace of Popeye.  Stephanie (Infinite Sea) and I had communicated about taking pictures of the sign that stated that fact.  I also took pictures of a large lighted marker anchored to a tug that had sunk outside of the channel earlier in the month.

The Queen of the Mississippi docked at Chester, IL.

Chester, IL. claims to be the birthplace of Popeye.  The Chester Yacht Club proudly advertises it on the side of their club house...'Popeye City'.

More barge traffic as the navigatable part of the river narrows below Chester.

Marker for the sunken tow boat.

In the meantime, Todd had communicated with the tow captain of a large approaching barge unit.  After Todd positioned OB to pass the barge, a large log presented itself right in our path so Todd moved OB a little more to starboard.  BANG !!!!  Todd instantly and instinctively tried to move OB off the water covered weir dam.  OB shuttered in anger!

Click on the picture to see the weirs in the middle of the river better.

This is the actual track from our Navionics.  It's easy to see where we hit the weir dam and how we narrowly missed the next two as we moved back into the navigatable part of the river.  Stranger yet, I looked at our log from our 2010 Loop...we hit a log just 5 miles before this point that caused prop damage.  Too much of a coincidence!

This is a picture of a chevron weir dam like the one we hit...only the one we hit was submerged and supposed to be one we could travel over.

These are wing dams.  Weirs are also built like these only they are under water and come from the shore into the river.  Gravel lining the shoreline is a hint there are weir dams coming from the shoreline.

Another hint is the way the water looks.  The water where we were looked like th water on the left...there just wasn't enough water.

Todd put OB in neutral and instantly went back to check to see if we were taking on water.  The earth and time stopped for those moments.  I had pictures of us sinking to the bottom like the tug we'd seen marked a few miles back.  Todd called back to me in the bridge and had me maneuver OB first in forward then reverse, one engine at the time.  Then he had me turn the rudder starboard (right) and port (left).  No water was coming in, both shafts were turning without vibration and the rudder stems seemed fine.

As all this unfolded, we had communicated with Infinite Sea what was happening as they passed us.  They waited ahead.  A tow at the coal dock we had just passed also called to offer help.  We were so thankful for all who watched and worried as we flounder for those moments.

Todd called the approaching barge that was nearly beside us letting the captain know we were sitting in place until he passed.  Next was to test OB’s ability to move.  OB was sitting between two weir dams as Todd carefully maneuvered OB to the sailing line (deep water and the boating channel).  OB maneuvered well.

Next was to bring OB slowly up to the 900 RPM we’d been running to see how she responded.  There was some vibration but nothing really bad.  We breathed a sigh of relief.  We knew we had prop damage and hoped our rudders, shafts, struts and cutlass bearings (everything aft of the engines that make OB move and turn) were okay.

The rest of the day was somewhat of a blur as we worried about what we couldn’t see (the underside of the boat).  Our next test was to turn into the Mighty Mississippi’s current to get into our anchorage for the night.  Todd had to increase the RPMs to 1200 to 1500.  There was a little more vibration but much less than we expected.

We had followed Infinite Sea for the entire trip.  They were in constant contact.  Once anchored, Stephanie and Paul came back to OB on their dinghy and spent a pleasant evening with us on the bridge.  It gave us time to thank them for staying with us even after we knew OB was manageable and was good for navigation.

 

A mural wall at Cape Girardeau, MO.

Looking downstream at the Mighty Prop Eating Mississippi River behind us.

Looking upstream in the Little Diversion Canal with Infinite Sea, UnTide, Canadian Flyer and a sailboat in front of us.

 The night was peaceful.  Little Diversion Canal was our anchorage during Loop #1.  It is a place where the boat never moves and we went to sleep listening to crickets and tree frogs.

What follows was taken from public blogs as well as from the Army Corps of Engineers who put in and manage the weir dams in the Mississippi.  By all rights we should have been able to move over the weir dam without hitting it.  Once out of the water, we found if there had been as little as 2 to 6 more inches of water we’d have passed unscathed.

The Mississippi River is perhaps the U.S’s most visible and enduring example of an altered river. Where the Upper Mississippi River was once free flowing with islands, backwaters, and wide floodplains to support diverse fish and wildlife, it is now a series of pools, created by an extensive lock and dam system. The Mississippi’s conversion to a “working river” that can support barge transportation was achieved by the U.S. Army Corps of Engineers’ (Corps) extensive work to manipulate and harness the river’s natural flow, functions and features.

In addition to the 29 locks and dams on the River, the Corps maintains a 9 foot deep navigation channel on the river using “river training structures” like chevrons, wing dikes, and bendway weirs.  These structures are placed in the river to help the river self- scour and reduce the need for dredging. Between 1980 and 2009, the Corps built at least 380 new river training structures in the Middle Mississippi, including 40,000 feet of wing dikes and bendway weirs between 1990 and 1993. The Corps built at least twenty-three chevrons between 2003 and 2010. (That’s what we hit…see the picture below of our actual track taken from our Navionics).

The Corps frequently argues that these new structures are more cost effective and create a more diverse stream bed, which can be environmentally beneficial. However, the Corps’ St. Louis District office has not documented any adverse or beneficial impacts, relying on mostly models and a handful of surveys that do not fully support the Districts’ claims that these structures are eco-friendly. Despite the addition of so many new structures to the river, the Corps has not updated their environmental impact statement since 1976.

Even more concerning for many riverside communities along the Mississippi River are concerns that adding these structures to the river bottom is significantly increasing flood levels. At least 51 peer-reviewed scientific studies demonstrate that river training structures are significantly increasing the risks of floods for riverside communities. These structures have increased flood levels by up to 15 feet in some locations and 10 feet in broad stretches of the river where these structures are prevalent. Despite the evidence of increasing flood risk, the Corps denies the validity of these claims.  (http://www.americanrivers.org/blog/flood-risk-rising-mississippi-river/)

Weirs:

A weir is like a dam that is designed to be topped. That is to say, it's a structure that's built under the surface of the river's water to change the flow characteristics of the water. Bendway weirs are a popular concept for reducing the erosion and meandering problems noted above. Weirs angled upstream appear to cut down on the amount of erosion on the outer bank of the river by minimizing the secondary currents of the river spinning outward.  (http://www.theatlantic.com/technology/archive/2011/05/what-weve-done-to-the-mississippi-river-an-explainer/239058/2/)

The hydraulic effects of the weirs reduce erosion on the outer bank of the bend by reducing flow velocities near the outer bank, reducing the concentration of currents on the outer bank of the bend, and producing a better current alignment through the bend and downstream crossing. In addition, the Bendway Weir is able to solve many stream alignment problems while simultaneously improving aquatic and stream corridor habitat

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Navigable River Weirs:

In a navigable river a Bendway Weir is a rock sill (5,000 pound maximum weight stone) located in the navigation channel of a bend, usually angled 20 to 30 degrees upstream (into flow), spaced from 400 to 1,400 ft apart, varying in length from 400 to 1,600 ft, and level-crested at an elevation low enough to allow normal river traffic to pass over unimpeded. The weir should be high and long enough to intercept a large percentage of flow at the river cross-section where the weir is located. Weirs are typically built in sets (4 to 14 weirs per bend) and are designed to act as a system to control velocities and current directions through the bend and well into the downstream crossing. (http://chl.erdc.usace.army.mil/chl.aspx?p=s&a=ARTICLES;109)