Are you using the OpenRoads tools to create the pond?.
I don't have a video for the pond creation in OpenRoads but the workflow below should help you.
- Create the base for the pond using the design tools.
- Asssign a linear template to the base to create the earth banks of the pond.
- Create a terrain surface of the pond design.
- Use the Analyse Volumes tool to report volume to a Plane, which can be set as the Water level.