T&P in Weatherford Texas

I could sure use some help from anyone familiar with T&P in the Weatherford area of Texas around 1900. Family legend has it that my great-great grandfather worked as a bridge engineer on the line there. But wasn't most of the line already done by 1900? What would a bridge engineer in Weatherford be doing? I'd appreciate any thoughts you might have on the subject.

Many thanks!

He would probably be involved with maintaining the structures.

Railroads are often upgraded. Wooden bridges from about 1880 were untreated and would need replacement. Iron bridges needed replacement with steel. New locomotives might not fit through truss structures. Perhaps street underpasseswould be needed.
Bridge engineer? Useful fellow!
B Burton