Q.Will Pampas grass die if run over?
This year I decided to plant Pampas grass. Unfortunately it was at the same time the power company decided to replace a power pole on my property. The grass was up to about 2.5 ft before they flattened it to the ground. After they left I went out and cut it (at ground level) where it broke in half. Just wondering if it will recover or should I plant another.

Certified GKH Gardening Expert
Usually, this kind of damage will not affect the grass much, however, cutting back at this time will. It is best to leave them damaged and cut them in early spring, as they use the dead tops as insulation from the winter.
If you don't see any growth by next spring, then it is likely that the untimely pruning will have caused the premature death of the grass.
This article will help you with the care of Pampas Grass: https://www.gardeningknowhow.com/ornamental/foliage/pampas-grass/growing-pampas-grass.htm