>>716123750
Realistically you just lure them to drop off from a destroyed bridge forever

If that somehow isn't accepted by you then concrete funnels that lead into rotating sawblades (with guys on the other end with billhooks pulling out the stumps that come out the other side)

Or just incineration traps, giant fields of fire and so on. Or just use construction equipment to crush literallly endless amount of zombfags like >>716124998