The Feather River Route line segment is divided into the following subdivisions:
∑ UP Fresno Subdivision from BNSF Stockton Sub Xing to El Pinal
∑ UP Sacramento Subdivision from El Pinal to Haggin [and Oroville]
The former Western Pacific line through Stockton has been closed from Scotts (just south of the former location of Stockton Tower, now known to the UP as BNSF Stockton Sub Xing) to the former crossing of the ex-WP and ex-SP lines at El Pinal. The ex-SP line is used instead for both the route from Stockton to Haggin (ex-WP) and that from Stockton to Elvas (ex-SP). The ex-SP segment is two Main Tracks, CTC-controlled, while the remaining ex-WP line is single-track CTC-controlled. Speeds are 40 mph through Stockton, 60 mph on the ex-WP (after a 20 mph restriction through El-Pinal), and 40 mph again in the Sacramento area.
At the former location of Stockton Tower (BNSF Stockton Sub Xing, MP 84.7), the ex-SP Fresno Subdivision crosses the BNSF Stockton Subdivision on a flat crossing with two tracks in each direction. In addition to little-used connectors in the south-to-east (lower right) and south-to-west (lower left) quadrants, there is an east-to-north connector (upper right) quadrant, built in the mid 1990s after the mergers, from the north track of the BNSF at Keddie Junction to Church (MP 84.5), which also has crossovers to permit access to both main tracks. There is a spur for storage of Altamont Commuter Express trains at Market (MP 84.2), which use the former SP depot on the west side of the line at Stockton (ACE), MP 84.0. One mile north of the depot, at the former WP flat crossing at El Pinal (MP 83.0/95.1), the ex-WP single-track line curves north-northwest while the former SP two main track line continues north.
Once past the 20 mph speed limit through the junction at El Pinal, the speed limit rises to 60 mph. At North Channel, the former WP line to the Stockton Harborís north side once went west. The straight and level line across the San Joaquin and Sacramento River Deltas has an 11,715 ft. siding at Hammer Lane (MP 97.7-100.4), followed by Kingdon (MP 104.7), a hold signal at CP F105 (MP 104.9), the location of Terminous Junction, where the WP branch to Terminous on a navigable waterway once headed west, Villinger (MP 107.8), a former crossing with an SP branch to Brackís Landing on that same waterway, Los Vinos, a detector at MP 109.5, a 3,400 ft. siding at Thornton (MP 113.5-114.3), where the line turns due north and crosses the Mokelumne/Consumnes River(s), Glannville, and a 6,171 ft. siding at Phillips (MP 121.3-122.6). There is a detector at MP 124.7, Franklin, a spur at Laguna Creek (MP 129.8), where the speed limit drops from 60 to 40 mph, a 4,416 ft. siding at Pollock (MP 131.9-132.9), Kenwood (MP 133.2), where there is a spur, Cordova (MP 134.4), where there is a spur, and a 13,301 ft. siding at the former WP yard (on the east side of the line) at South Sacramento (MP 134.2-136.9), where the WP locomotive shops once occupied the west side of the line and the speed limit falls to 25 mph. Turning north-northeast under a bridge carrying the Sacramento light rail tracks, and passing the former location of the WP Sacramento depot on the west side of the track, the line passes under the SP line between Sacramento and Elvas and reaches the junction with the connectors north from that line at Haggin (MP139.8).