USGS Hydrologic Investigation of West Africa's Congo River (part one)

The following podcast is a product of the USGS Eastern Region Office of Communications and the South Carolina Water Science Center.

[Intro]: Audio mix–from audio diary of John Shelton: "The Congo River is incredible, it's like no other river you could ever imagine. Unknown depths and species of fish that have never been identified, and flow volumes that are ten times greater than that of Niagara Falls. We really didn't know what we were in for. At one point a whirlpool opened up on the right side of the boat, it was just a perfect structure, just incredible circulation it was, you could see the gapping hole.  And, I yelled a Ned and gentleman in the front of the boat; they were looking in the opposite direction and our boat driver, who is a local Congoleese and did not speak English, veered the boat over into the whirlpool. The boat tipped and was now stuck in the whirlpool, and I am frantically trying to get out, and suddenly we realized that we were heading upriver with no boat driver. Going in we did have a plan, but we had to understand that it probably wasn’t going to work and just be ready to improvise and come up with a different strategy."

That's John Shelton USGS Data Chief for the South Carolina Water Science Center. Join us as today as we chronicle the triumphs and tribulations on a USGS investigation of the Congo River. I'm Ray Douglas, and you are tuned to Water Science for a changing world.

Douglas: John, thanks for talking with us today. I’m sure there are very few USGS hydrologists with experience breeding pythons. Could that have been why you were chosen for this expedition?

Shelton: slight chuckle...Thanks for having me. That is true, that was a hobby I had for a brief period in college, but no longer a python breeder, but it probably didn’t play much of a fact in me going to the Congo. Actually, I was asked in 2005 by Headquarters staff to go to Iraq and do some acoustic work in Iraq with some Iraqi engineers and assist in developing hydrologic monitoring networks, and so I think when the opportunity came up to go to the Congo, Headquarters said, Well, John was crazy enough to go to Iraq, maybe we can talk him into going to the Congo.  

Douglas: Can you give us an overview of the teamwork that it took to make this mission possible, and the individual tasks for each team?

Shelton: We had three distinct teams who were working on this project, but the primary team was the biologists who were working with the American Museum of Natural History, and they were concerned with were tasked with looking at the different fish species in the lower Congo River, identifying those species, finding their location, how many different locations were they found in the river, and what their interaction with other species was. The second team was the Kayak Team, who was actually National Geographic’s Adventurer of the Year, they were tasked with taking videography and still photos down reaches of the Congo that had never been seen before. They were also going to be able to collect some pretty important data for us. We were going to rig up their kayaks with special scientific equipment for looking at bathymetry in the river, how deep is the river down the center line from 85 mile reach. They were going to have GPS on the kayaks be able to give us pinpoint locations of those depths. Then we also gave them water quality sampling supplies, they were going to take water quality samples in all the tribs that they ran into on different parts of Congo. The third team was going to be Ned Gardner and myself. Ned worked for the American Museum of Natural History, and we were classed as the Hydrology Team, we were going to be quantifying total flow volume and doing some pretty intense velocity and bathymetry mapping.

Douglas: What was your first impression when you arrived?

Shelton: We landed in Kinshasa, which is the capitol city in the Democratic Republic of the Congo. It has a population of greater than ten million people. But, it also has an unemployment rate of somewhere between 80 and 90 percent. And Zulu villages we stayed in had absolutely nothing… no electricity, no running water, but the people were some of the most happy, hospitable, open people I’ve ever met. They were awesome.

Douglas: And what about the Congo, the river itself? What were your first impressions of it?

Shelton: We went to an area just below Kinshasa, just below Malaybo Pool called the Kinsuka Rapids, and that’s an area of somewhat restriction in the river where there’s an incredible amount of flow and pretty restricted area. And our first sight of that river at that location was just awestruck, with just waves and boils and explosions in the river that was just like nothing I’d ever seen before in the U.S. It was, it was breathtaking, awesome river.

Douglas: John, in reviewing your field notes, I noticed that there was some concern early on when you first saw the rapids, and some of your team members wanted to resort to a different way to view the river. Can you tell me a little about that?

Shelton: Umm...the kayak team after they saw the banks from the river really needed an aerial view so they could scope out their entire trek of the river. They were going to do an 85 mile run of a reach of the river that had never been successfully navigated, so we needed to see if we could get in an aircraft that could go over that area to see what the best routes were. At that time the government in the DRC (Democratic Republic of Congo) was not really happy with the idea of a private flight over the river, but through our efforts with National Geographic, they were able to do some negotiating, and the government allowed us to go in an aircraft. That airplane ride was incredible. We went from just below Kinshasa almost to the coast, I believe, and the Congo is just, it’s so huge, it’s hard to explain with words, but some of the features we saw in the river were turbulence structures, and rapids, and whirlpools, and boils, and being able to define those structures from the air was incredible, because you knew if you could define those features at that altitude, then the absolute magnitude on the river was going to be tremendous.

Douglas: Can you tell us a little about your idea to turn these kayaks into death-defying data-collection devices, and just what they were supposed to reveal.

Shelton: Sure, we decided that if we could outfit those kayaks with echo sounders, which included transducers in the hull of the kayaks, which would send a pulse to give us river depth, we were also going to equip them with data loggers, so that all of the depth measurements, which would be continuous down the reach of the river, would be logged, and then also georeferrenced; so we had to have GPS (Global Positioning System) and receivers mounted in the kayaks to give the location of those depths. We were going to merge all that data into a single file, so that we would be able have a single line depth recording down an entire 85-mile reach of the river. What we came up with was just an awesome kayak system, and it was to have all that equipment mounted in a single vessel that was not designed to collect that kind of data, was just impressive. We were excited to see what we had done and how it was going to work.

Douglas: You've engineered quite a kayak there. Now tell us about the test.

Shelton: That test was just just incredibly exciting. We were just below Malaybo Pool, we had a huge group of the locals there with us. They were excited. They had never seen anybody try to put a boat in those waters, they were so rough, so turbulent, such huge waves, and it was just an awesome, awesome sight. We outfitted the boats, we put them in the water and sent them on about, it was probably less than a mile run just as a preliminary test to see if everything was going to function properly. And made the run, and the coolest part about that was watching the locals and hearing the response when they saw those boats make it through those rapids, there was just this huge roar of excitement and cheering, to see those boats paddle back over. They ran over, and with the guys still in their boats, the locals grabbed the front and back of the boats and lifted them up on their shoulders like they was war heroes and brought them back to the beach and…We sat down and pulled the data out of the files and looked to see if anything had worked, and it was perfect. We had gotten a great bathymetry plot of that three quarter mile run below Malaybo Pool and everything was good to go.

Douglas: So everything works... what’s next?

Shelton: The kayakers took all the equipment they needed and they were off, it was going to be a four-day trek for them, they were going to do 85 miles in 4 days and collect samples we needed and collect the bathymetry and georeferrenced information down this 85-mile stretch. So now it was up to Ned and I, we were going to start our journey. We were going to start the velocity and bathymetry mapping in the lower reaches of that 85-mile stretch.

Douglas: Alright, well hold it right there… I understand that USGS brought a secret weapon.

Shelton: We did bring a secret weapon; that secret weapon was an acoustic Doppler current profiler. That particular instrument is used to profile velocities at multiple locations. We could map 3-diminsional velocities and depths in real time, and that data is updated multiple times per second. We were able to map 3-diminsional velocities to perfectly demonstrate what those turbulence flow structures looked like and how they were related to upstream flows and changes in bed form.

Douglas: John, I was reviewing some of the footage, and I noticed that on one of those voyages, you almost got a little too close to one of those turbulence structures. Can you share with us what happened?

Shelton: The turbulence there was unbelievable, and I was just awestruck by some of the turbulent features we were seeing. At one point a whirlpool opened up on the right side of the boat, it was just a perfect structure, just incredible circulation it was, you could see the gaping hole. I yelled a Ned and gentleman in the front of the boat; they were looking in the opposite direction I yelled and pointed to point out this whirlpool to them; and our boat driver, who was a local Congoleese and did not speak English, saw me yelling and pointing, and I’m afraid that he thought I wanted to see the structure close up, so he veered the boat over into the whirlpool. The boat tipped, all our equipment was rolling around, and finally the boat righted itself, we recovered all our equipment and our hearts started beating again, we  breathed a sigh of relief and suddenly we realized that we were heading upriver with no boat driver. The boat had tipped, the driver had propelled himself over backwards from the boat and was now stuck in the whirlpool, frantically trying to get out, so I jumped to the back of the perog, it's a carved wooden canoe, turned the boat around, went back and Ned and the gentleman from National Geographic were able to grab our boat driver and pull him back in the boat and… we were back on.

Douglas: John, thanks for stopping by today and setting the stage for this three part episode. By the way, what was the name of your driver?

Shelton: Our boat driver’s name was Papa Durock; Toppa realized on that particular day the importance of personal flotation devices and life vests, and we never saw Pappa without a life vest the remainder of the trip.

Douglas: You've listening to part one of a special USGS hydrologic investigation of the Congo River in west Africa. Be sure to join us next month as this episode continues on Water Science for a Changing World.

[Close] Water Science for a changing world is a product of the U.S. Geological Survey's Eastern Region Office of Communications and the South Carolina Water Science Center. Audio mix–from audio diary of John Shelton.