As more water drains into the Blue River, it’s physical size greatly increases.

 

Once a Flowline StreamRiver (a 1-Dimensional feature) is equal to or larger than 100 ft across, it is represented in the NHD as an Area StreamRiver (a 2-Dimensional feature).  Because the flow network is built on NHDFlowline features and not on NHDAreafeatures, an NHDFlowline Artificial Path is added within the NHDArea StreamRiver in order to maintain network connectivity.