I think actually the opposite of what you said is correct.
built the two new towers in 1992-1993 to reduce the strain on controllers working in the old central tower (built with the airport in 1974.) The plan as I remember it from newspaper articles back then was to split the airport between the two towers during the day. At night, when things calmed down, the central tower would handle operations.
Of course, this was back when Delta's DFW
hub was very large (second largest in the system before DL
beefed up SLC
). Back then, we were hearing all kinds of talk about how DFW
was going to surpass Chicago and Atlanta to become the nation's busiest airport. Of course, that didn't happen - we're now fourth, behind ATL
The old central tower now looks like it's been mothballed. It's highly unlikely the FAA would close the two new towers after investing millions of dollars in them.
As an aside: DFW
has seven towers total: the three FAA towers, the American ground control tower between Terminals A and C, and ramp control towers on Terminals A, C and E. The new International Terminal D also looks like it's going to have a ramp control tower.
Dallas Love Field has four towers - the old main tower on top of the terminal (from 1958), the newer FAA tower built in 1990 or so, and the two ramp control towers (built in 1968 for American and Braniff, and now used by Southwest and general aviation operators, respectively.)