Today due to damming projects primarily by Israel the Jordan rarely exceeds 100ft in width, and 10ft in depth.
The Estuary is the widest point.
thames
The widest point of the tennessee river is near the tributary of the ohio river, reaching 1 1/2 miles wide at its widest point.
The estuary between Shoeburyness and Sheerness is 8 Km wide. The estuary between Whitstable and Foulness is 29 Km
The merced river gets up to 50 ft wide at its widest point.
It gets wider all the way to the sea, like most rivers.
The river mersey is 1.2km
300m
26km at chelyabinks
The River Thames flows into an estuary near Southend in Essex. It is actually between the Counties of Essex and Kent where it meets the North Sea.
8,979
the mouth
That would be the River Thames.