Known Defect with River & Flood Analysis

Issue:
After installing River and Flood Analysis on a PC with Civil 3D, and after you add any components from that module there are two (2) separate issues.
1. You cannot delete viewports in Paper Space
2. If you try to Erase => All, if will leave the viewports, but will erase all data in Modelspace

 

Causes:
This is currently a known defect in Civil 3D and is currently under review with the developers under these defect numbers:
CIVILX-178 - Erase All Defect
CIVILX-90 - Viewports are not erasable

 

Solution:
If you encounter this issue, the only way to remove the viewports from Paperspace is to use the Cut (Ctrl +X) to remove them