Rolling Loess Prairies

In the span of two weeks this summer, streamflow here plummeted from over 2,100 cubic feet per second down to under 21—a swing of more than one hundredfold in either direction. The trigger was simple: late June's dry spell followed by July's storm.What's striking is the speed. Before European settlement, rolling loess prairie dominated this landscape—dense root systems that worked like a sponge, slowly absorbing summer rain and releasing it steadily through the growing season. That natural buffer is gone. Today's row crops shed water almost instantly, sending it racing downslope into streams that are already warm and nutrient-rich—conditions tailor-made for algal blooms. The timing of peak flow hitting the warmest, most algae-prone moment of the year is no accident; it's how the landscape now works.