Total bridges
184
Public highway bridges in Box Elder County
County profile · official public datasets
Box Elder County, UT
184 public highway bridges tracked in the FHWA National Bridge Inventory: 23.4% rated Good, 70.7% Fair, 6% Poor.
- 184
- Public bridges
- 23.4%
- Good condition
- 6%
- Poor condition
The verdict
According to the Federal Highway Administration's 2024 National Bridge Inventory.
Box Elder County pairs a higher-than-median Poor-condition share among rated counties in the state with an older average build year than the state inventory.
- 26th
- of 29 on Poor share
- 6%
- Poor-condition share
- 184
- public highway bridges
- 1977
- avg year built
Poor is an FHWA condition category from the lowest applicable component rating (4 or below), not a live crossing-safety or closure decision. Rankings cover counties with at least five public highway bridges.
Box Elder County Bridge Snapshot
According to the Federal Highway Administration's 2024 National Bridge Inventory, Box Elder County ranks #26 of 29 Utah counties with at least 5 public highway bridges on Poor-condition share (lower share ranks better; currently 6%). Box Elder County, Utah contains 184 public highway bridges. Roughly 23.4% are rated “Good,” 70.7% “Fair,” and 6% “Poor.” Poor means the lowest applicable deck, superstructure, substructure, or culvert rating is 4 or below on the 0–9 NBI scale. It is a condition category, not a live safety or closure decision.
Responsible agencies inspect covered bridges on risk-based intervals under current NBIS rules and submit inventory data to FHWA annually. The list below shows every NBI-tracked bridge in the county. Use the “Sort by” controls to change the ordering, and click any row for its reported inspection date, traffic count, and condition fields.
Source: FHWA National Bridge Inventory. See methodology for full definitions.
Good condition
23.4%
43 of 184 rated 7-9
Fair condition
70.7%
130 of 184 rated 5-6
Poor condition
6%
11 of 184 rated 4 or below
In-state Poor-share rank
#26 of 29
Among Utah counties with 5+ bridges, lower share ranks better
Condition distribution
Share of 184 NBI-tracked bridges by lowest applicable component rating.
Good 23.4% (43)
Fair 70.7% (130)
Poor 6% (11)
Box Elder County's Poor-condition bridges carry 10,641 vehicle crossings a day
That is 0.6% of the county's reported daily bridge traffic on 6% of its bridges: Poor-condition structures carry less traffic than their share of the inventory. Each Poor bridge averages 967 crossings a day against 10,462 for a Good-condition one. A Poor rating is a condition category, not a closure or a live safety judgement; it means the lowest applicable component rating is 4 or below.
Computed over the 182 of 184 bridges in this county that report an average daily traffic count. Source: FHWA National Bridge Inventory, 2024 release.
46.7% of Box Elder County's bridges have passed the 50-year mark
86 of the 184 bridges with a recorded construction year were built in 1974 or earlier. Age alone is not a defect: a well-maintained older bridge can rate Good, and 23.4% of this county's inventory does. Even so, this older cohort is the population from which future Poor ratings are drawn, which is why the age profile below matters alongside the condition split above.
Cutoff derives from the 2024 release year minus a 50-year design life. Source: FHWA National Bridge Inventory, 2024 release.
One structure carries 79.1% of the county's Poor-condition bridge traffic
SR-126 over I-15 (SR-15) NBL AND SBL, built 1968, carries 8,412 vehicles a day, the most of any Poor-rated structure here. The county's Poor-condition exposure is concentrated rather than evenly spread, so the 11-bridge count understates how much of the daily burden sits on a single crossing.
Share is of the 10,641 daily crossings on Poor-rated bridges that report a traffic count. Source: FHWA National Bridge Inventory, 2024 release.
When Box Elder County's bridges were built
184 bridges with a recorded construction year, grouped by decade
- 1910s 1
1910–1919
1 bridges
- 1920s 1
1920–1929
1 bridges
- 1930s 6
1930–1939
6 bridges
- 1940s 12
1940–1949
12 bridges
- 1950s
1950–1959
16 bridges
- 1960s
1960–1969
36 bridges
- 1970s
1970–1979
35 bridges
- 1980s
1980–1989
24 bridges
- 1990s
1990–1999
23 bridges
- 2000s 11
2000–2009
11 bridges
- 2010s
2010–2019
17 bridges
- 2020s 2
2020–2029
2 bridges
What this shows Construction peaked in the 1960s, when 36 of the county's bridges still in the inventory were built, which is 19.6% of those with a recorded year. That cohort is now 55 to 64 years old in the 2024 inventory. Its average build year is 1977, 7 years older than the Utah average of 1984.
How Box Elder County compares with Utah's closest counties by inventory size
The 5 Utah counties nearest Box Elder County in number of bridges, with their condition splits. Its 6% Poor share is the 6th-lowest of these 6. Its average build year of 1977 against a peer-group mean of 1985 is 8 years older.
Showing the 5 closest of 28 Utah counties eligible for comparison.
| County | Bridges | Good | Fair | Poor | Avg. built |
|---|---|---|---|---|---|
| Box Elder County (this page) | 184 | 23.4% | 70.7% | 6% | 1977 |
| Washington County | 177 | 20.3% | 78.5% | 1.1% | 1987 |
| Sevier County | 157 | 19.1% | 80.3% | 0.6% | 1983 |
| Davis County | 139 | 28.8% | 70.5% | 0.7% | 1996 |
| Summit County | 138 | 14.5% | 81.2% | 4.3% | 1982 |
| Weber County | 129 | 14.7% | 80.6% | 4.7% | 1979 |
Each share is of that county's own total tracked bridges; peers are the counties with 5 or more bridges whose inventory size is closest to Box Elder County's. Source: FHWA National Bridge Inventory, 2024 release.
Nationwide counties with similar inventory size or average build year
Two NBI-derived peer sets for Box Elder County, both outside Utah so the neighborhoods are not the same-state size table above.
Similar inventory size
Nearest county inventories outside UT (184 bridges here).
- Independence County, AR · 184 bridges
- Mills County, IA · 184 bridges
- Henderson County, KY · 184 bridges
- Adams County, OH · 184 bridges
Similar average build year
Nearest mean year-built outside UT (1977 here).
- San Diego County, CA · avg 1977 · 1,632 bridges
- King County, WA · avg 1977 · 1,238 bridges
- Riverside County, CA · avg 1977 · 1,117 bridges
- Shelby County, TN · avg 1977 · 1,077 bridges
Source: FHWA National Bridge Inventory, 2024 release. Peers floor at 10 bridges so stub inventories cannot own the match.
Poor-condition bridges (11)
15600 N.ST. CO.RD.
PoorOver: WEST CANAL
5800 W. 15600 N. GARLAND, Box Elder, UT
Built 1950 Load: 7.8 t ADT: 189
TOWN ROAD
PoorOver: MALAD RIVER
WEST SIDE OF ELWOOD, Box Elder, UT
Built 1969 Load: 14.3 t ADT: 265
TOWN STR.-FA. #526
PoorOver: DEEP CREEK
WEST SIDE OF SNOWVILLE, Box Elder, UT
Built 1941 Load: 15.9 t ADT: 417
TOWN ROAD-FA.#512
PoorOver: MALAD RIVER
W. OF I-15 INT. IN ELWOOD, Box Elder, UT
Built 1945 Load: 24.0 t ADT: 338
SR-126
PoorOver: I-15 (SR-15) NBL AND SBL
4200 N 2350 W, Box Elder, UT
Built 1968 Load: 28.8 t ADT: 8,412
POCATELLO VAL.CO.R
PoorOver: I-84 (SR-84) EBL & W
POCATELLO VALLEY INTER, Box Elder, UT
Built 1959 Load: 29.8 t ADT: 20
450 SO.ST. TOWN RD
PoorOver: CORINNE CANAL
350 E. 450 S. FIELDING, Box Elder, UT
Built 1940 Load: 30.1 t ADT: 13
CO. RD. 25800 NO.
PoorOver: MALAD RIVER
1 MILE EAST OF PORTAGE, Box Elder, UT
Built 1930 Load: 31.4 t ADT: 125
COUNTY ROAD
PoorOver: WEST CANAL
2.5 MILES E. OF FIELDING, Box Elder, UT
Built 1945 Load: 31.4 t ADT: 71
COUNTY ROAD
PoorOver: MALAD RIVER
SOUTH SIDE OF ELWOOD, Box Elder, UT
Built 1978 Load: 32.1 t ADT: 146
CO.RD.-INTCHG.X-RD
PoorOver: I-84 (SR-84)
AT THE BOTHWELL INTERCHG., Box Elder, UT
Built 1989 Load: 42.1 t ADT: 645
Read our methodology - how this data is sourced, computed, and verified.
Related
Data sourced from official public datasets. See our methodology for details. Retrieved and formatted by PlainBridges
Every figure on PlainBridges is rendered directly from federal source data, no number is typed in by an editor. This page draws directly on federal source data, no figure is typed in by an editor. See our editorial standards & corrections policy, the methodology behind these numbers, or report a data error. NBI condition categories reflect the latest reported inventory record, not a live safety, closure, or travel decision.