2019 Mississippi River

[mahtoo]

The LA511 web site does not have LA Hwy 15 closed YET (LA HWY 15 is the road that goes over just about all the structures at Morganza) When I went in 2011 they did not allow any parking on most areas of La hwy 15 and you had to keep moving. Stopping was not allowed and there were plenty of State police and what looked like unmarked patrol cars in the area. While this is obviously a point of interest, I think the main cause of concern is a run away barge or a sea going vessel losing steering. If that happens and causes damage to a levee then is Katie Bar the door. Deep draft vessels can go only as far north on the Mississippi River as the Hwy 190 Bridge in Baton Rouge. I don't know what kind of restrictions the coast guard has on navigation on the Mississippi or if there are any plans to do so. Maybe somebody can provide that info

I drove through Morgan City yesterday and the river is very high there and has been for some time.

While not surprised, I was not expecting them to open Morganza right now. Water levels and flow rates at the ORCS are close to, but still less than when they opened in 2011. I suspect they are allowing for the anticipated crests that are a result of the continued rain in the upper Mississippi river basin. I did hear there is a flood event on the Arkansas river right now. I don't know if the Arkansas river drains to the Mississippi River or to the Red River. FYI the red river connects to the Atchafalaya and not the Mississippi River just to the west of the ORCS. The Atchafalaya is a distributary of the Red River And the Mississippi rivers. 100% of the flow of the Red river goes to the Atchafalaya. The Atchafalaya is no small river and carries a lot of water. I suspect that most of the silt carried by the Atchafalaya is from the Red River Basin.

Hwy 1 is the hwy over the Morganza structure. Hwy 15 is the hwy over the structures at the Old River Complex several miles north of the juncture of Hwy 1 and 15. I suspect that is what you meant.

At times in the past tender boats were kept in the area near to the ORC to hopefully assist/prevent any barge traffic from being sucked into the OR structures. I would be surprised if a tender boat is not on standby already. Tender boats were also employed in the area on the Miss R in the area upstream of the old 190 bridge, across from Southern Univ, to assist barge traffic heading downstream. I forgot the name of the point in that area but from looking at the curve/alignment of the Miss you can imagine why navigation in that area during high water would be tricky at best.

I'm not aware of any restrictions to navigation at this time.

I've not kept track of flow rates so I'm not sure how close to the 1.5M cfs and rising we are. The major concern at this time is to prevent overtopping of the Morganza structure itself.

[HelmutVII]

A picture is worth a thousand words.😁😁😁

[Ragin4U]

https://www.mvn.usace.army.mil/Missi...tageDischarge/

Someone will have to explain these numbers!!

[HelmutVII]

I have to cut my grass . will interpret later tonight.

[CajunEXPRESS]

According to this source the Arkansas River is a tributary of the Mississippi River.

https://www.google.com/search?client...75.OZVwrSAf0_w

[CharlieK]

Logjam removed in 1849.....not 1950

[LouisianaB]

https://www.wafb.com/2019/05/28/park...-river-levels/

[HelmutVII]

According to this source the Arkansas River is a tributary of the Mississippi River.

https://www.google.com/search?client...75.OZVwrSAf0_w

Then may be one of the reasons they are opening the Morganza sooner than 2011.

[HelmutVII]

https://www.mvn.usace.army.mil/Missi...tageDischarge/

Someone will have to explain these numbers!!

The first table is a listing of river data at different stations along the Mississippi river from Venice to Cairo Illinois. These are not the only river stations that are monitored, these are just selected stations. The second column is the Water surface elevation at the station based on NAVD88 (North American Vertical Datum) 2004.65. the third column is the same information that has been adjusted to NAVD. NAVD is using the DATUM or zero point) as Mean Sea level with 0.0 being the elevation at sea level taking into account high and low tides. As you can see from Venice to Knox Landing (at the ORCS). The values go up as you would expect. Stations above Knox Landing have an asterisk because they are not based on NAVD the number is arbitrary. So according to todays report the water level is 64.4 feet above sea level at Knox landing. I will get back to this later. The final column is the 24 hour deviation. In one row you will see discharge at 1,355,000 CFS. This appears to be the flow rate of the river at Red River landing (could be Baton Rouge) with a deviation of -7000 cfs from the previous 24 hour period.

The second table is the same information for the Atchafalaya River. The Latitude discharge is shown at 1,951,000 cfs. This could be for both the river itself and the Wax Lake outlet I am not sure. That's a lot of water and is more than the Mississippi river.

The final chart is the information at the three ORCS structures, showing the water surface elevation on each side of the structure. The delta head is the difference between the river side and the channel side. Todays values are 19.8, 19.0 and 21.0 feet. This corresponds to about 9.0 psi at the bottom of the structure. That doesn't sound like much but it is about 1300 pounds per square foot. Considering the size of the structure and number of square feet involved it adds up pretty quick.

Getting back to the water surface elevation at knox Landing being 64.4 feet. This is at mile 313.5 (give or take) this corresponds to a slope of 0.205 feet per mile. The distance from the mouth of the Atchafalya river to the same location is about 155 miles. This corresponds to a slope of 0.415 feet per mile. That means that the slope of the water surface going down the Atchfalaya is twice the slope of the Mississippi River. The common understanding is water flows down hill, MORE ACCURATELY water flows in the DIRECTION OF THE DOWNSLOPE OF THE ENERGY GRADE LINE. ANY river monitoring station will provide the guage reading which is a measure of the WATER SURFACE ELEVATION. This is a very important piece of information along with the average velocity of the water. These two pieces of information will allow a computation of the potential energy (water surface elevation ) and kinetic energy (velocity squared divided by 2 times the acceleration due to gravity). Without getting into detail, AND VERY SIMPLIFIED everything is based on an energy balance using Bernoullis theorem along with Mannings formula (to calculate energy losses due to friction) to perform open channel flow calculations.

IF you REALLY REALLY REALLY want to study some more about this subject I suggest this book

https://www.amazon.com/Open-Channel-.../dp/1932846182

It is the bible of open channel flow and the same book I used when I took CIVE 454 in college. Some say it is a substitute for a sleeping pill. Others say it is the best text book ever written. It can be both.

[Oiler]

The first table is a listing of river data at different stations along the Mississippi river from Venice to Cairo Illinois. These are not the only river stations that are monitored, these are just selected stations. The second column is the Water surface elevation at the station based on NAVD88 (North American Vertical Datum) 2004.65. the third column is the same information that has been adjusted to NAVD. NAVD is using the DATUM or zero point) as Mean Sea level with 0.0 being the elevation at sea level taking into account high and low tides. As you can see from Venice to Knox Landing (at the ORCS). The values go up as you would expect. Stations above Knox Landing have an asterisk because they are not based on NAVD the number is arbitrary. So according to todays report the water level is 64.4 feet above sea level at Knox landing. I will get back to this later. The final column is the 24 hour deviation. In one row you will see discharge at 1,355,000 CFS. This appears to be the flow rate of the river at Red River landing (could be Baton Rouge) with a deviation of -7000 cfs from the previous 24 hour period.

The second table is the same information for the Atchafalaya River. The Latitude discharge is shown at 1,951,000 cfs. This could be for both the river itself and the Wax Lake outlet I am not sure. That's a lot of water and is more than the Mississippi river.

The final chart is the information at the three ORCS structures, showing the water surface elevation on each side of the structure. The delta head is the difference between the river side and the channel side. Todays values are 19.8, 19.0 and 21.0 feet. This corresponds to about 9.0 psi at the bottom of the structure. That doesn't sound like much but it is about 1300 pounds per square foot. Considering the size of the structure and number of square feet involved it adds up pretty quick.

Getting back to the water surface elevation at knox Landing being 64.4 feet. This is at mile 313.5 (give or take) this corresponds to a slope of 0.205 feet per mile. The distance from the mouth of the Atchafalya river to the same location is about 155 miles. This corresponds to a slope of 0.415 feet per mile. That means that the slope of the water surface going down the Atchfalaya is twice the slope of the Mississippi River. The common understanding is water flows down hill, MORE ACCURATELY water flows in the DIRECTION OF THE DOWNSLOPE OF THE ENERGY GRADE LINE. ANY river monitoring station will provide the guage reading which is a measure of the WATER SURFACE ELEVATION. This is a very important piece of information along with the average velocity of the water. These two pieces of information will allow a computation of the potential energy (water surface elevation ) and kinetic energy (velocity squared divided by 2 times the acceleration due to gravity). Without getting into detail, AND VERY SIMPLIFIED everything is based on an energy balance using Bernoullis theorem along with Mannings formula (to calculate energy losses due to friction) to perform open channel flow calculations.

IF you REALLY REALLY REALLY want to study some more about this subject I suggest this book

https://www.amazon.com/Open-Channel-.../dp/1932846182

It is the bible of open channel flow and the same book I used when I took CIVE 454 in college. Some say it is a substitute for a sleeping pill. Others say it is the best text book ever written. It can be both.

Definitely the sleeping pill.....😴

[Ragin4U]

The first table is a listing of river data at different stations along the Mississippi river from Venice to Cairo Illinois. These are not the only river stations that are monitored, these are just selected stations. The second column is the Water surface elevation at the station based on NAVD88 (North American Vertical Datum) 2004.65. the third column is the same information that has been adjusted to NAVD. NAVD is using the DATUM or zero point) as Mean Sea level with 0.0 being the elevation at sea level taking into account high and low tides. As you can see from Venice to Knox Landing (at the ORCS). The values go up as you would expect. Stations above Knox Landing have an asterisk because they are not based on NAVD the number is arbitrary. So according to todays report the water level is 64.4 feet above sea level at Knox landing. I will get back to this later. The final column is the 24 hour deviation. In one row you will see discharge at 1,355,000 CFS. This appears to be the flow rate of the river at Red River landing (could be Baton Rouge) with a deviation of -7000 cfs from the previous 24 hour period.

The second table is the same information for the Atchafalaya River. The Latitude discharge is shown at 1,951,000 cfs. This could be for both the river itself and the Wax Lake outlet I am not sure. That's a lot of water and is more than the Mississippi river.

The final chart is the information at the three ORCS structures, showing the water surface elevation on each side of the structure. The delta head is the difference between the river side and the channel side. Todays values are 19.8, 19.0 and 21.0 feet. This corresponds to about 9.0 psi at the bottom of the structure. That doesn't sound like much but it is about 1300 pounds per square foot. Considering the size of the structure and number of square feet involved it adds up pretty quick.

Getting back to the water surface elevation at knox Landing being 64.4 feet. This is at mile 313.5 (give or take) this corresponds to a slope of 0.205 feet per mile. The distance from the mouth of the Atchafalya river to the same location is about 155 miles. This corresponds to a slope of 0.415 feet per mile. That means that the slope of the water surface going down the Atchfalaya is twice the slope of the Mississippi River. The common understanding is water flows down hill, MORE ACCURATELY water flows in the DIRECTION OF THE DOWNSLOPE OF THE ENERGY GRADE LINE. ANY river monitoring station will provide the guage reading which is a measure of the WATER SURFACE ELEVATION. This is a very important piece of information along with the average velocity of the water. These two pieces of information will allow a computation of the potential energy (water surface elevation ) and kinetic energy (velocity squared divided by 2 times the acceleration due to gravity). Without getting into detail, AND VERY SIMPLIFIED everything is based on an energy balance using Bernoullis theorem along with Mannings formula (to calculate energy losses due to friction) to perform open channel flow calculations.

IF you REALLY REALLY REALLY want to study some more about this subject I suggest this book

https://www.amazon.com/Open-Channel-.../dp/1932846182

It is the bible of open channel flow and the same book I used when I took CIVE 454 in college. Some say it is a substitute for a sleeping pill. Others say it is the best text book ever written. It can be both.

"This corresponds to about 9.0 psi at the bottom of the structure. That doesn't sound like much but it is about 1300 pounds per square foot."
"This corresponds to a slope of 0.415 feet per mile. That means that the slope of the water surface going down the Atchfalaya is twice the slope of the Mississippi River. "

Incredible.
Thanks for the edification. Hydraulics is a complicated field but you do a good job of dumbing it down!

[HelmutVII]

"This corresponds to about 9.0 psi at the bottom of the structure. That doesn't sound like much but it is about 1300 pounds per square foot."
"This corresponds to a slope of 0.415 feet per mile. That means that the slope of the water surface going down the Atchfalaya is twice the slope of the Mississippi River. "

Incredible.
Thanks for the edification. Hydraulics is a complicated field but you do a good job of dumbing it down!

Thanks for your kind words.

Opening of Morganza is postponed.

https://katc.com/news/covering-louis...QcPlyd0LV-ziKU

Water levels near the ORCS have fallen a little over a half of a foot in the past 7 days. I was wondering why they were going to open it at levels lower than when they opened in 2011. I wonder if they will delay sinking of the barge in the Bayou Chene?

[Turbine]

Arkansas River bursts through levee north of Little Rock.

https://amp.usatoday.com/amp/1297285001

[cajunfan79]

Arkansas River bursts through levee north of Little Rock.

https://amp.usatoday.com/amp/1297285001

would this delay the opening of the morganza, being water that would have been channeled down south now spilling out? Don't know the effect it has futher down here, maybe someone with knowledge can chime in?

[Ragin4U]

would this delay the opening of the morganza, being water that would have been channeled down south now spilling out? Don't know the effect if has futher down here, maybe someone with knowledge can chime in?

I think it's got to make its way back to the river at some point. But you are right, maybe a delay, maybe a little lower level on the Mississippi