Here are some great false color satellite images of the confluence of the Grand River and the Missouri Rivers. These photos were taken in 1992 (lower image) and then during the historic 1993 flood (upper image). The Grand River is coming in from the northwest (upper right) on these images and then flood waters are filling the entire valley - valley wall to valley wall. The curent flood levels on the Grand and Missouri Rivers at this location are less than in 1993, but appear to be within the top 10 percent of floods since 1900 at this location.
River Refuge @ Alligator Cove (see previous post) is approximately 90 river miles upstream of this location.
Landsat Thematic image. Bands 5, 4, and 2 mapped to red, green, and blue respectively. Images from Goddard Space Flight Center.