Versions:
-Minecraft Forge: 14.23.5.2847
-Industrial Renewal: 0.17.6

What happens:
Built a dam according to specs like in the video tutorial, except one intake is along a section of dam that's one block back from the other, but otherwise both dam segments have enough of their own concrete.

One intake is working at 100% efficiency, but the one that's one block back, says that it's own block is an invalid dam block.
Full message:

Efficiency: 76%
Concrete Amount: 110/143
Dam Intake at: X:-8765 Y: 52 Z:-6628 is not a valid dam block

and the coordinates read-out matches the block I clicked on

What should happen:
Both intakes should be operating at 100% efficiency

There is gravel in the side