| State: | UT |
| Type: | SR |
| Route: | 13 |
| Map Custom: | yes |
| Map Notes: | SR-13 highlighted in red |
| Section: | 107 |
| Length Mi: | 33.135 |
| Length Round: | 3 |
| Established: | 1977 |
| Direction A: | South |
| Terminus A: | in Brigham City |
| Junction: | in Brigham City in Corinne in Elwood in Tremonton in Riverside |
| Direction B: | North |
| Terminus B: | near Plymouth |
| Previous Type: | SR |
| Previous Route: | 12 |
| Next Type: | SR |
| Next Route: | 14 |
State Route 13 (SR-13) is a state highway in northern Utah, running 32.841miles parallel to I-15 in Box Elder County from Brigham City to Riverside. Most of SR-13 is a former routing of U.S. Route 191.
SR-13 begins at an intersection with US-89 and US-91 at the south end of Brigham City and heads north through the city, then turns west at the north end of the city to intersect I-15 and I-84. It continues northwest across the Bear River through Corinne and turns north parallel to I-15 and I-84 through Bear River City. It intersects I-15 and I-84 at Elwood and continues north around the east side of Tremonton.
North of Tremonton, SR-13 continues north through Riverside and Plymouth, turning northwest to end at another intersection with I-15 near Plymouth.
The road from SR-1 (by 1926 US-91, now SR-90) in Brigham City north to the Idaho state line became a state highway in 1910.[1] It was initially assigned the State Route 17 designation in the 1920s,[2] but in 1927 the state legislature changed the designation to State Route 41.[3] The portion south of SR-42 (now SR-102) in Tremonton became part of U.S. Route 30S in 1926,[4] and the entire route became Utah's portion of a southern extension of U.S. Route 191 in the late 1930s.[5] A new alignment around Tremonton and Garland was defined in 1935, with the old route becoming SR-82.[6]
The SR-41 designation was dropped in 1962, as State Routes 1 to 5 were assigned to proposed Interstate Highways (in Utah law; the routes were never signed as such), and SR-41 was on the route of I-15, which was SR-1 under Utah law. However, since I-15 near Brigham City was almost complete, only the portion of SR-41 north of Riverside was assigned SR-1; the remainder was instead renumbered as an extension of SR-84, which had ended at Hot Springs Junction north of Ogden.[1] Since the original proposed alignment of I-15 would have passed east of Tremonton and Riverside, this extension of SR-84 turned east at Riverside, following present SR-30 to SR-154 (Garland Road). When SR-154 was removed from the state highway system in 1969, SR-84 was extended farther east over part of it to SR-69 (now SR-38) near Collinston. Finally, in the 1977 renumbering, the part of SR-84 between Hot Springs Junction and Brigham City was redesignated US-89, and State Route 13 was created for the portion between Brigham City and Collinston.
By 1982, proposed I-15 had been moved west to its current alignment north of Tremonton, and a new SR-129 was created to connect it with Riverside along present SR-30. For continuity, SR-13 was cut back to Riverside, with the Riverside-Collinston portion also becoming SR-129. SR-13 was extended north from Riverside to I-15 at exit 392 near Plymouth in 1988, replacing what had been maintained as temporary I-15. A small realignment was made in 2008 at the SR-83 intersection in Corinne, moving SR-13 from the diagonal routing alongside the rail line to a straight north - south routing on 4800 West.
