Workers have been excavating the sides of the crossing under State Route 180 (SR 180) outside of downtown Fresno, preparing for the construction of a retaining wall with a rebar mesh and sprayed concrete (also known as shotcrete). Crews have approximately 15 feet more to excavate before they reach the bottom of the trench where a concrete box will be constructed that will carry the trains under SR 180, a rail spur and the Dry Creek Canal.