Steve – a couple of questions re post 28. I’ve never had my boat in or west of the Mississippi, at least not above Empire or so. These are new guy questions.
First, during early May the River was 13-14’ and falling at the Carrolton gage. Just by eyeball, the current was substantial in that period. I think I know that, during normal stages, the current runs 2.5 – 3.5 k at New Orleans. I also know that the current varies substantially depending on local features at any given point in the River. Any idea as to the magnitude of the River currents you encountered between the Industrial and Harvey locks? How did you evaluate that in your planning?
Second, why did you choose Harvey versus the downstream Algiers locks?
I’ve enjoyed following your travels and hope to heck to attend one of your get-togethers – just can’t seem to get schedules to work.
I know that this was directed to Steve but I would like to chime in if I may.
First of all, I can’t think of any ‘normal’ current in the Mississippi River. It varies by where you are and the ‘fall’ of the river over a short distance, what the width and depth of the river is, how many bends are in a stretch and the vessels position within the bend. It takes years of experience to read the river and even a section you know well varies from day to day.
That said, the section from Algiers Lock to Harvey Lock has only one major bend though it’s a doozy (Algiers Point) which is all of a sharp 120 degree turn and has the deepest sounding in the river at about 180’ mlw. At high river, down bound traffic are fighting like crazy to make the bend. If you are up bound, best be tucked well inside the point to stay clear of vessels being swept to the outside of the point. It is interesting to watch a large ship or tow work this bend, they start the turn after passing under the GNO Bridge which is a mile upstream. By the time the are into the bend and fully broadside to the stream they are making four knots sideways!
Traveling east to west along the ICWW upon exiting Industrial Lock you have two choices, turn left and head down bound about a mile to the Algiers Lock which is a straight shot with no bends. Or turn right and head upriver about eight and a half miles against the current and around Algiers Point to the Harvey Lock.
The local river gauge is at Carrollton Bend which is further upriver again from Harvey Lock. Low river is considered anything below three and a half feet on the Carrollton Gauge. Mean current at that gauge is 2-3 knots.
High river is considered anything above twelve feet on the gauge. Mean current will be at least five knots. Note that is mean current, it may be higher or lower in places. At this stage the USCG requires additional hp on tows, additional rigging on tows and barge fleets and additional reporting requirements. You don’t want to fall overboard in these conditions, even with a life jacket. You are likely to be swept away, dragged under and many unfortunates end up under barges in fleets where there is no way to get to the surface. Although I say that the mean current is five knots I have seen eight knot vessels struggle to average one knot upriver at this river stage.
At fourteen feet on the gauge the river is really running hard. The pressure on the levees is substantial. The Corps of Engineers will start opening gates on the Bonnet Carre Spillway to divert some flow into Lake Pontchartrain. It will never be allowed to go above 18’ because levees would top or fail. Once Bonnet Carre is fully open, they will start to open the Morganza Spillway above Baton Rouge which diverts water into the Atchafalaya Basin. This has only happened twice in the 40 years or so I have lived and worked on the river.
So, in my opinion, if the river is anything over say 5-7’ on the gauge, it’s a no brainer to use Algiers Locks if you are inexperienced on the river.
Both locks have published telephone numbers. If you have doubt, call the individual Lock masters to find out if you will have any delay in locking through. Harvey Canal is much more industrialized than the Algiers Cut Off Canal. You are likely to meet much more commercial traffic moving in and out compared to the Algiers Canal where you will meet larger but fewer steadily moving tows. There is a reason the traveling (non local shift tows) tows use the Algiers Locks. It’s easier.
Hope this helps your planning thoughts.
