How wide was the Yalu battle area?

How wide was the river mouth where the Yalu battle took place?

The relevant Korean Bay and river-mouth area was roughly 20 kilometers, or about 12 miles, across.

The action took place in the broader Korean Bay and Yalu mouth area rather than a narrow river channel. The estimated span was roughly 20 kilometers, or about 12 miles. That width left room for opposing fleets, escorts, and transports to maneuver rather than forcing them into a confined passage. The answer makes the battle map and the convoy's operating space easier to visualize.