USGS Hydrologic Investigation of West Africa's Congo River (part 3)
USGS South Carolina Water Science Center Data Chief, John Shelton in a special hydrologic expedition down the Congo River, West Africa. Part three of the three part episode, reveals a hydrologic data set that changed the world record books.
Location Taken: US
The following podcast is a product of the U.S. Geological Survey's South Carolina Water Science Center
[Intro]: Audio and mix–from audio notes of John Shelton - Crew and Congo River Sounds continue to end.
John Shelton: The Congo river is incredible it's like no other river you have ever imagine. Unknown depths, unknown species of fish, and the flow volume is ten times that of Niagra Falls.
Going in we did have a plan but some of the stretches of the lower Congo had never been successfully navigated, and you had to be ready to improvise and come up with a different strategy. We really didn't know what we were in for.
Ray Douglas: That's John Shelton USGS Data Chief for the South Carolina Water Science Center. Join us today as we chronicle the final triumph of this USGS investigation of the Congo river. I'm Ray Douglas, and this is Water Science for a Changing World.
John it's been a long journey but thanks for having a seat with us to finalize this chapter on the Congo river. I understand that some of the same equipment used here in the States was use to measure the Congo River, in particular the Acoustic Doppler Current Profiler.
John Shelton: Yes the ADCP is one of the fastest growing technologies for stream flow measurement in the USGS. It has wide spread use across the country and is providing an outstanding piece of equipment for stream flow measurement.
Ray Douglas: John isn't data collection your primary duty here in South Carolina?
John Shelton: That's right, we're concerned with collecting data at approximately two-hundred stations across the State and making sure that data is high quality and in on time.
Ray Douglas: And, how was it that USGS came about being chosen for this job on the Congo?
John Shelton: The researchers on the project had been in contact with our hydrologist in our Connecticut center named Dave Berkley who had done some of the model predictions. And, it was actually on Dave's recommendation that they contact headquarters because he knew that we had the ability and the equipment to be able to verify these extreme variation in velocity and possibly the extreme variation in depth as well.
Ray Douglas: John what are some of the key differences in how you use the data logging equipment there on the Congo compared to how you use it here in the U.S.?
John Shelton: In just general stream flow monitoring networks everything is built to sustain some type of flood condition. But as far as installing a depth sounder and GPS system and data-logger in a kayak to sustain an eighty-five mile trek down one of the biggest rivers in the world, and most violent rivers in the world, we had to come up with some pretty unique applications in order to go through some of the extreme conditions like this, I am pretty sure it's a first.
Ray Douglas: You certainly had some unique equipment but you also had some pretty unique performers on your team, eighty-five miles? that's a pretty big trek.
John Shelton: I gotta give Trip Jennings a little credit here, it was he and his team of kayakers who agreed to make this trek, twice! And just getting back up river, the eighty-five mile stretch was an all day affair because keep in mind this is deep in the heart of the Congo and transportation is very difficult. But they were going back up for the second time down one of the most powerful rivers in the world. And were totally excited and happy to be able to do that for us.
Ray Douglas: And again, who actually initiated this exploration, and why was it so important?
John Shelton: The primary investigator on this trip was Dr. Melanie Stiassny with the American Museum of Natural History in New York. Her theory was these fish were in isolated populations due to some physical differences within the river. Whether it be extreme depths or incredibly varying velocities.
Ray Douglas: And in particular, what did USGS have to offer here?
Melanie needed some ground truthing of the theories that were going on of about what the physical characteristics of the river were that were causing these changes in species. And so, the USGS was recognized as a leader in this kind of technology and so they asked us if it would be possible to put a hydrologist on the ground to verify these predictive models.
Ray Douglas: Well there was a lot of interest in catching a Tiger fish, and I am sure your staff are going to remember the electric catfish by all means. But was there any other fish species there that helped determine that the depths were actually real.
John Shelton: The species that sticks in my mind the most is Lamprologus Lethops and the interesting fact is that we only found those species dead. And every fish that we found generally had air-bubbles under the skin. Those air-bubbles and no eyes really indicated that the fish was a depth dweller. And the theory then was that some force was causing these fish to come up from great depths at a rapid rate and they were getting a fatal decompression sickness.
Ray Douglas: So John let's get back to the kayakers and where we left off with episode two. Can you reconnect us there and take us back in?
John Shelton: So the kayakers had agreed to perform their trek a second time another eighty-five mile trek. I was a little leery and hesitant but after the extreme letdown of the failure the first time I was also very excited that they were willing to do this. We were able to piece together some equipment we had along with us and make some repairs of what we assumed had cause the failure and send them on their way. And, based on their prior ordeal, they were hoping to get down as fast as they could and not run into anybody they didn't want to run into. So eighty-five mile trek, did it two days and night of the first day they slept on an island in the middle of the river.
Ray Douglas: O.K. so they are back, and what were the results?
John Shelton: When we were reunited with them and pulled the data from the cards we were just... ecstatic to see that it has been one-hundred percent successful. We had documented a single line bathemetry trek down that eighty-five mile reach and had recorded depths in excess of seven-hundred and fifty feet. Just an incredible data set.
Ray Douglas: Well not only did you data support Melanie's theory but rumor has it that the data had a little prize of it's on. Can you tell us about that?
John Shelton: Not only did the data that we collect support Melanie's theory that the different hydraulic structures in the river segregated these and made new species but we had also documented the deepest river in the world at seven-hundred fifty-five feet.
Ray Douglas: John can you give us an idea through comparison how deep some of those canyons actually are?
John Shelton: To give you an example or put this in to perspective we were seeing these extreme variations in depth of couple hundred feet. With depths in excess of five-hundred feet, the Hoover dam is around five-hundred feet, U.S. Capital or Niagra Falls around two-hundred feet. I think the Golden Gate is somewhere from the top of the highest tower around seven-hundred forty-six feet so we could have submerged the Golden Gate in these holes of the Congo.
Ray Douglas: Other than the raw data, was this investigation documented, to prove it, in any other way?
John Shelton: Well everywhere we went we had the crew of at least three National Geographic television members with us. They were recording and interviewing everywhere we went.
Ray Douglas: That's great so you actually have, documentation, data and did they produce a show?
John Shelton: Yes they did, they did a great job and from all the footage they were able to collect they produced an episode of National Geographic Explorer called "Monster Fish of the Congo".
Ray Douglas: John I know the Congo was quite the test but it seems the data did pay off. And it looks like from the footage, everyday after work you had plenty to do, the kids were there waiting.
John Shelton: The kids were great they would be at our camp every afternoon, every evening and follow us around. I couldn't understand them and they couldn't understand me but we played and, they were just a lot of fun.
Ray Douglas: John any closing thoughts from you experience from this region of the world?
John Shelton: Some of the villages we stayed in were in the middle of nowhere and those people had absolutely nothing, no vehicles, no running water, no electricity, but they were just incredibly happy and helpful and just wanted to do whatever they could to help us out, they were, they were awesome folks.
Ray Douglas: John, thanks for taking the time to talk with us.
John Shelton: Thanks any time.
Ray Douglas: You've been listening to part three of a special USGS investigation of Africa's Congo River.
Water Science for a changing world is a product of the U.S. Geological Survey's South Carolina Water Science Center.