- Grade Separation Underpasses - Dalhart TXA set of grade-separation underpasses was constructed in 1939 with the assistance of the United States Bureau of Public Roads. Two underpasses allow railroad traffic to span Denrock Ave.; one underpass brings Railroad St. (U.S. 87) under rail traffic. Multiple plaques on site read: C.R.I.&G. AND F.W. & D.C. RY. UNDERPASS Built in 1939 by the Texas Highway Department --- United States Bureau of Public Roads --- State Highway Commission Brady Gentry - Chairman Harry Hines - Member Robert Lee Bobbitt - Member Julian Montgomery Highway Engineer R. R. Tway Contractor