Grade control structures like check dams and ground sills are commonly used to manage hazards in steep streams. Experiments showed that these structures do not always reduce slope or limit sediment transport as expected. Instead, they can cause fluctuations in bed level and sediment transport. The size of sediment particles plays a big role in these fluctuations. Despite the presence of grade control structures, the slope of the stream did not decrease. The structures did, however, change how sediment is stored and released, leading to more frequent but smaller sediment pulses.