The M.E. tested diatom levels in the bodies and it turns out the unsub drowns his victims at different locations every time, not just where he abducts them or where the bodies are later discovered.
Research revealed that the same high truancy levels were to be found in every inner city district.
levels
The probability of this chain of events all happening at once is one in 2 million flights - about once every two months at current levels of air traffic.