Early morning at the Econlockhatchee River near Orlando
It's currently out of its banks and into its floodplain. While this is a bummer for hiking and biking, floodplain inundation is crucial for many aquatic species. The calm flooded water provides a temporary safe haven for many species to breed. These species also provide food for predators that take advantage of the flooding.
Many plants have evolved to thrive with periodic inundation as well. The cypress tree is a great example. A leading hypothesis on the function of the "cypress knees" or pneumatophores that you can see in this picture is that they provide a means for gas exchange through the root system when it's submerged and the water becomes anaerobic. They also likely provide advanced structural support.
Unfortunately, many rivers in the USA have been so modified by channelization, dams, or canals that proper floodplain connectivity is often not adequately achieved and the effect is detrimental on not only the surrounding riparian ecosystem, but also many ecosystems downstream, even including coral reefs which are my study system for my dissertation