At flood stage

We sampled the last two Fridays without mishap (9/19/08 & 9/26/08). Thompson Lake water depth is about 2.5 m, up about 0.6 m from the summer. On the 26th, a cyanobacteria bloom was evident with a more dense bloom at the south end. The news for us has been on Lake Chautauqua. On the 19th, as we sped by motor boat to the south end, I noticed a lot of drift wood in water. Sometimes when the water rises, it floats wood from the banks and you have to keep an eye open to avoid bigger pieces. But we also noticed the water was darker. Upon reaching the south end, we saw the river was coming "in" through Quiver Lake, which is a connected lake to the Illinois River. At this spot, pelicans were gathering, I'm guessing because it was good fishing. I took a bottom core and it is hard to see in this posting, but about 1-2" new sediment had come into our sampling site. I also post a picture of our sampling rig - our old Cheyenne and double-axel trailer . . . hey, they aren't pretty but they get the job done. We had parked the rig on dry pavement and upon returning in our boat (the students have name it the "Prairie Shark"), we saw thing had gotten pretty wet. The lake had risen in depth at about 7" in 2 hours! We thought things might have stabilized by Friday (9/26) but we measured river current of 0.40 m/sec at the south end and 0.26 m/sec in the middle of the lake. Although it is thought that, someday, Thompson will be opened to the IL River like Chautauqua, the connection will be under greater management. Still, our comparative study continues to yield interesting, and hopefully valuable, results. You can see the water level for the Illinois River at Havana, IL in the graph shown here or at this site.