CLAIM: Critics believe that supernatural events like these are absurd. Is it possible that this event actually happened?
RESPONSE: If you do not believe in God, then miracles are impossible. However, if an all-powerful God exists, then shutting off a river’s water would be no more difficult than shutting off a water faucet.
The Jordan River has dried up before. At various times (specifically in 1927), an earthquake at Tell ed-Damiyeh caused the Jordan River to dry up for roughly 24 hours. Hess observes, “From a geological perspective, the Jordan River Valley lies at the juncture of tectonic plates that create an unstable region. Earthquakes can occur and have been known to block the flow of the river.”
Naturalistic scholars argue that a natural earthquake was responsible for this miracle, but we don’t see how this fits the text. The text tells us:
(1) This was predicted according to perfect timing. The waters stopped (3:15-16) and resumed (4:18) as soon as the priests entered and exited. If we can explain away the miracle by appealing to an earthquake, we still cannot explain away the miracle of the predictions that Joshua gave.
(2) This occurred during flood season (v.15). In other words, the text is going out of its way to demonstrate that the waters were rushing before the miracle occurred.
(3) The waters piled up as a “heap” (v.13, 16) and they were “completely cut off” (v.16). This doesn’t fit with the concept of an earthquake swallowing up the water into the Earth, or blocking them with a physical obstruction.
(4) The land was “dry” in the river bed (v.17). An earthquake upstream would have stopped the water, but it wouldn’t have left the ground “dry.” Surely, the riverbed would have been sludgy and muddy.
(5) The point of this miracle was to demonstrate that God was with Joshua just as he was with Moses at the Red Sea (v.7). Consequently, naturalistic scholars also argue that the parting of the Red Sea has a naturalistic explanation (but see comments on Exodus 13:18).
For these reasons, we disagree with the naturalistic scholars regarding this miracle. God is free to use naturalistic means, but this is not the description of this event.
 Hess, Richard S. Joshua: An Introduction and Commentary. Downers Grove, IL: InterVarsity, 199(6) 104-105.