Outflow weir
If you will notice, there was very little water in the outflow weir. The water never got much higher than that. It was my fault. I did not realize that the concrete sides and seams in the flume would pass water just as easily as the soil. Thus the part of this experiment that was intended to measure bulk saturated hydraulic conductivity of the soil mass failed because of inadequate control on the boundary conditions. It did, however, show that this kind of sensor could be used to indicate the rise of the phreatic surface in an embankment. The next time, I would seal the concrete.