Floodplains come in lots of shapes and sizes. This was evidenced by the rainstorms that moved through North Carolina at the end of December. Those storms came over a period of two days dropping between 2 and 3 inches of rain across most of the region.
With most plants dormant this time of year, there was little uptake of the rain and most of it found its way to our local streams, lakes, and rivers. Indeed, according to one news report, the levels at Jordan Lake peaked at about 17 feet above its normal levels due to wet and wetter conditions in December 2015.
For most of our area floodplains, this was their time to show off what they do. That is, as stream channels get filled to capacity and overflow, floodplains fill and function to slow the velocity of water, reduce its stress on eroding stream banks, and infiltrate flood waters back into the soil.
It’s not always a quick process, either. Low down in the watershed near Kinston, the Neuse River can flood its banks and have its floodplains inundated for weeks. Closer to the headwaters of the Neuse, Rocky Branch at NC State’s campus can overtop its banks and have its flows return to its banks within hours after a heavy storm.
Whether it’s in the lower or upper watershed, having a stream that is able to access its floodplain is a natural process and helpful in reducing downstream flooding, replenishing groundwater, and improving water quality.