Mississippi Basin Model construction and instruments

Regular readers may remember my earlier posts about the Mississippi Basin Model from early 2010, July 2010, and Dec. 2010. This was the most comprehensive hydraulic model ever built, meaning it covered the largest land extent of any model. The Corps of Engineers also built a Chesapeake Bay Model and one of San Francisco Bay. The Chesapeake model only had a full operational life of three years and is now gone.  But the San Francisco model still exists and is open to visitors in a warehouse in Sausalito.

Building a model like this is a complex project requiring precise scaling and ultra-precise shaping of the terrain. I found some photographs that help explain how a scale physical hydraulic model like this is constructed.

In the first photograph, metal templates that show the topography have been laid out across the soil at specified intervals. The templates usually have vertical exaggeration, such as 1:10, meaning vertical distance is scaled 10 times greater than the horizontal scale. Then the soil is moved and shaped to approximately match the templates.

At the Mississippi Basin Model, the original earth work, excavating canals, and installing piping was performed by German prisoners of war.  The Germans were repatriated in 1946, and civilian employees completed the rest of the model.  The template method of shaping the terrain was used between 1946 and approximately 1953. But the expansive soil in the area required a shift to the contour method of construction (not shown in these photographs).

In the second photograph, the workers are carefully pouring concrete and shaping the surface to exactly match the top of the templates. This is painstaking work requiring years of experience. The labor, time, and space requirements underscore why building physical models is so expensive.

This is an electronic water-level follower, meaning an instrument to measure water level. Notice that electronic circuits means vacuum tubes!

Finally, here is one of the Stevens chart recorders that plots the water level over time. As the paper drum turns, an ink pens moves up and down on the guide rails.

This is a January, 2010, photograph of one of the controls rooms at the Basin Model. Since then, all the Stevens recorders have been removed, probably stolen.

Historical black and white photographs courtesy of the Coastal and Hydraulics Laboratory, Engineer Research and Development Center, US Army Corps of Engineers.

Shelter 3 at the Waterways Experiment Station, Vicksburg, Mississippi

In the previous article, I described how the Waterways Experiment Station in Vicksburg, Mississippi, formerly conducted numerous tests using hydraulic models. Some were outside, like the famous Mississippi Basin Model in Jackson (see the December 2010 update). But most models were inside shelters or hangars to keep them out of the weather and limit dirt and debris.
Shelter 3 is an example. There is nothing glamorous about it; it is just a steel roof over a dirt floor. When complete, it covered 97,300 square feet of model space. Most of this shelter will be torn down soon, so the models were dismantled and miscellaneous equipment was moved out in 2010.

(Notice the "blooming" around the windows and doors. This is diffraction that occurs when the source of light is many stops brighter than the main part of the image. It is worse with small-sensor point-and-shoot cameras. High-speed black and white film would have responded similarly because of the thickness of the emulsion, but a thin, low-speed film like Kodak Panatomic-X would have minimized the blooming. The quality of the lens coating and the number of elements also affects diffraction.)
Until the building is demolished, it serves as a convenient place for employees to park cars. In a 1949 aerial photograph of the lab, a low wood shelter occupies this location, but in a 1981 photograph, this steel building is present. Many of the World War II-era wood shelters were replaced with steel in the 1960s.
A few treasures remain. A sizable collection of file cabinets and map cases contain old project files. As time goes by and technicians retire, fewer and fewer remain who remember what the files pertain to. It is unlikely that a hydraulic model would ever be rebuilt, but most Corps of Engineers projects, such as locks, dams, and waterways, last for centuries, so the data in the files may be of value in the future. But how will these files be stored and organized? Eventually the bugs and mildew will eat the paper if they don't move the files to a climate-controlled space.
There is still one model in the north part of the shed, but I have not seen it used in a long time. It was a section model of the Dalles on the Columbia River. You see a number of odd little footprints in the soft dirt, probably raccoon. There are also fox on station
The south side of the shelter was used by a joint US Army Corps of Engineers and US Geological Survey program that developed and calibrated river sediment samplers. Measuring how much suspended sediment moves down rivers is difficult and labor-intensive because field crews have to cross the river and collect water samples at various depths. Bedload samples are even harder to collect and calibrate.
For the field work, they used sturdy Army Bridge Erection Boats. These were sent away to some other Army base. I like strange heavy-duty equipment like this.

All images except the last (the boat) are from my Panasonic G1 digital camera with a Lumix 14-45mm lens, tripod-mounted. The in-camera black and white mode is very nice, with results as good as reprocessing the RAW file.

Update April 30, 2012: The shelter is actively being dismantled.

Update: Mississippi Basin Model - Further Decline

Dear Readers, bad news: what is left of the famous Mississippi Basin hydraulic model in Jackson (in Butts Park off McRaven Street) has deteriorated noticeably in the last year.

This was the largest hydraulic model in the world, meaning it covered the largest continental land area ever to be assembled into one comprehensive tool to test water flows. It was last used during the 1973 Mississippi River flood when the Old River Control Structure was almost undermined. The structure's failure would have led to a large proportion of the river's flow going down the Atchafalaya River waterway rather then along the present path past Baton Rouge and New Orleans and on to the Balize Delta. The model was maintained through the 1970s but finally discontinued because of the expensive manpower requirements. The land was deeded to the Department of the Interior and subsequently to the City of Jackson in the early 1990s. Since then, trees and brush have covered much of the site, buildings have fallen down, and vandals have damaged equipment and stolen property.
You can get an idea of the vast size of this operation from the photograph above. This is part of the lower Mississippi below Vicksburg. The accordion-folded mesh serves as friction to simulate trees (hardwood bottom land) in the delta plain. This area is not as overgrown as other areas because of the broad expanse of concrete.
One of the compressor houses still has its roof, and the equipment inside is still present. Another one-story building on the site has completely collapsed. Another one suffered a fire so intense that the steel roof joists warped.
In the lower-river control house, a number of the Stevens chart recorders have been stolen since last January. These machines provided a permanent record of a flood in the form of stage hydrographs. They recorded on chart paper with pens, similar to tide recorders and just about every other type of technical data recorder in the mid-20th century.
The punched paper you see above was for the flow controller system. This controlled a variety of orifices in the flow controller tank, which in turn released precisely measured amounts of water to the model. The charts could be played back many times to rerun particular flow events or storms. A coworker told me that at one time, many bookcases were filled with these paper rolls. Fascinating technology, but I can imagine the manpower required.

You can see more photographs of the site in this January 2010 blog entry: Basin Model. If you want to see what is left, visit soon. The deterioration appears to be accelerating. It's really sad to let this historic civil engineering wonder go.

UPDATE JULY 2017:  A volunteer organization has been formed to clean and clear the site and develop it as an education/interpretive center. They have already done amazing work at clearing trees and cleaning off some of the concrete walkways. Readers interested in participating in the cleanup work, please contact: 

Sarah McEwen

President, Friends of the Mississippi River Basin Model

601-376-9131

Twitter: @MSRiverBasinMod

Facebook: @FriendsofMississippiRiverBasin Model

The Mississippi River Basin Model, Jackson, MS

The Mississippi River Basin Model at the Waterways Experiment Station (WES) was the largest hydraulic model ever built. It was also the most complex attempt ever undertaken to model the river system that drains a good part of the North American continent. The purpose of the model was to test the behavior of the 1.25 million square mile Mississippi River and Tributaries Project and evaluate levees, floodways, cutoffs, and reservoirs. The ambitious project was conceived by Lt. General Eugene Reybold in the early 1940s after smaller models had proven their worth in examining the behavior of individual projects.


During World War II, many engineers and technicians were serving in the war effort and manpower was scarce. General Reybold arranged to use German prisoners of war as laborers to clear and prepare the site. A site was chosen in Clinton, Mississippi, about 35 miles east of the Waterways Experiment Station in Vicksburg. By the end of the war, about 1,800 prisoners of the Afrika Korps were living nearby in an internment camp. I have read that many of these men were engineers and highly-trained professionals who worked on the project with enthusiasm and typical German precision and engineering prowess. (Also, this assignment may have been a bit more pleasant than cutting timber in lumber camps in Wisconsin in winter.). Some of the officers married Clinton women.

The project took 20 years to complete, with the last sections finished in 1966. WES used the model during the great flood of 1973 to predict what would happen if the Old River Control Structure in Louisiana were to fail, allowing a major portion of the of the Mississippi system's water to flow down the Atchafalaya watershed. The last use was in 1993, during the record-breaking floods of the Mississippi system in the upper Midwest. When the Corps planned to breach some of the main stem levees near Prairie du Rocher and Fort de Chartres, Illinois, the model was partially revived to examine water flow and effects of the levee breaches. The Corps finally closed the project permanently and turned the land over to the City of Jackson in 1993. The City of Jackson mowed the grass through 2006, but abandoned all maintenance after that.

The concrete portions of the model are still largely intact. You can easily visit the site by taking Springridge Road south from Interstate 20 and then turning left on McRaven Road. Turn left into Buddy Butts Park. Part of the site has a fence, but much of it has fallen down. The land is no longer clear as in the aerial photograph above, and brush and trees are slowly taking over. But, as of January 2010, you can still easily climb the observation platforms, walk around in the river basins, and pretend that you have walked from Morgan City to Sioux City.

The concrete shaping of the landscape was amazing. Imagine the survey skill required to precisely shape the terrain representing a major portion of the continent. The little pegs in the channels are friction elements.

Some of the buildings are falling down, but several of the control houses are largely intact.

Stevens paper chart recorders

The control buildings still have rows of Stevens paper chart recorders on shelves, abandoned in place just as if the technicians planned to return to work some morning. One of my coworkers was a property officer and remembers how she had to record the serial numbers on all the instruments and pumps annually. (July 2016 update: the recorders have been stolen.)

The massive pumps are still in place, slowly rusting and getting overgrown. From what I can tell, the City of Jackson does not maintain anything on the site. This is a good example of how nature takes over, a small scale experiment of the transitions speculated in the History Channel's Life After People.

I took these photographs on January 18, 2010 with an Olympus E-330 digital camera. The first three photographs in this blog are courtesy of the Coastal and Hydraulics Laboratory, Engineer Research and Development Center, U.S. Army Corps of Engineers, Vicksburg, Mississippi.

Update May 7, 2013 (anniversary of V.E. Day): The historian of Mississippi Valley Division, Mr. Charles Camillo, generously sent me this photograph of the POWs working on one of the drainage canals. Date and photographer not recorded. 

Update July 26, 2016: For more photographs of the Basin Model, please click the links:

http://worldofdecay.blogspot.com/2010/12/update-mississippi-basin-model-further.html

http://worldofdecay.blogspot.com/2010/07/update-on-mississippi-basin-model-in.html

http://worldofdecay.blogspot.com/2013/01/mississippi-basin-model-construction.html

http://worldofdecay.blogspot.com/2015/11/mississippi-river-basin-model.html

UPDATE JULY 2017:  A volunteer organization has been formed to clean and clear the site and develop it as an education/interpretive center. Readers interested in participating in the cleanup work, please contact: 

Sarah McEwen

President, Friends of the Mississippi River Basin Model

601-376-9131

Twitter: @MSRiverBasinMod

Facebook: @FriendsofMississippiRiverBasin Model