Total bridges
559
Public highway bridges in Larimer County
County profile · official public datasets
559 public highway bridges tracked in the FHWA National Bridge Inventory: 49% rated Good, 49% Fair, 2% Poor.
The verdict
According to the Federal Highway Administration's 2024 National Bridge Inventory.
Larimer County pairs a top-quartile lowest Poor-condition share among rated counties in the state with a newer average build year than the state inventory.
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.
According to the Federal Highway Administration's 2024 National Bridge Inventory, Larimer County ranks #16 of 64 Colorado counties with at least 5 public highway bridges on Poor-condition share (lower share ranks better; currently 2%). Larimer County, Colorado contains 559 public highway bridges. Roughly 49% are rated “Good,” 49% “Fair,” and 2% “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.
Total bridges
559
Public highway bridges in Larimer County
Good condition
49%
274 of 559 rated 7-9
Fair condition
49%
274 of 559 rated 5-6
Poor condition
2%
11 of 559 rated 4 or below
In-state Poor-share rank
#16 of 64
Among Colorado counties with 5+ bridges, lower share ranks better
Share of 559 NBI-tracked bridges by lowest applicable component rating.
That is 1.4% of the county's reported daily bridge traffic on 2% of its bridges: Poor-condition structures carry less traffic than their share of the inventory. Each Poor bridge averages 5,203 crossings a day against 8,152 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 557 of 559 bridges in this county that report an average daily traffic count. Source: FHWA National Bridge Inventory, 2024 release.
161 of the 559 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 49% 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.
SH 392 ML over CACHE LA POUDRE RIVER, built 1959, carries 19,000 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 57,230 daily crossings on Poor-rated bridges that report a traffic count. Source: FHWA National Bridge Inventory, 2024 release.
559 bridges with a recorded construction year, grouped by decade
1900–1909
1 bridges
1910–1919
2 bridges
1920–1929
7 bridges
1930–1939
19 bridges
1940–1949
12 bridges
1950–1959
29 bridges
1960–1969
76 bridges
1970–1979
48 bridges
1980–1989
102 bridges
1990–1999
58 bridges
2000–2009
78 bridges
2010–2019
99 bridges
2020–2029
28 bridges
What this shows Construction peaked in the 1980s, when 102 of the county's bridges still in the inventory were built, which is 18.2% of those with a recorded year. That cohort is now 35 to 44 years old in the 2024 inventory. Its average build year is 1987, 5 years newer than the Colorado average of 1982.
The 5 Colorado counties nearest Larimer County in number of bridges, with their condition splits. Its 2% Poor share is the 2nd-lowest of these 6. Its average build year of 1987 against a peer-group mean of 1987 is in line with the group.
Showing the 5 closest of 63 Colorado counties eligible for comparison.
| County | Bridges | Good | Fair | Poor | Avg. built |
|---|---|---|---|---|---|
| El Paso County | 686 | 31.3% | 65.5% | 3.2% | 1984 |
| Weld County | 614 | 36.8% | 58.5% | 4.7% | 1986 |
| Larimer County (this page) | 559 | 49% | 49% | 2% | 1987 |
| Adams County | 535 | 43.9% | 49.2% | 6.9% | 1990 |
| Jefferson County | 464 | 33.8% | 59.9% | 6.3% | 1984 |
| Denver County | 458 | 41.9% | 56.3% | 1.7% | 1991 |
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 Larimer County's. Source: FHWA National Bridge Inventory, 2024 release.
Two NBI-derived peer sets for Larimer County, both outside Colorado so the neighborhoods are not the same-state size table above.
Nearest county inventories outside CO (559 bridges here).
Nearest mean year-built outside CO (1987 here).
Source: FHWA National Bridge Inventory, 2024 release. Peers floor at 10 bridges so stub inventories cannot own the match.
Over: North Poudre Canal
0.7 Mi E of Co Rd 37, Larimer, CO
Over: SHEEP CREEK
50 FT SO OF LARIMER CR 80, Larimer, CO
Over: Dry Creek Tributary
0.8 Mi N of Co Rd 4, Larimer, CO
Over: Fall River
0.2 Mi W of US Hwy 34, Larimer, CO
Over: CO.RD 82 BUCKEYE ROAD
10 MI N OF WELLINGTON, Larimer, CO
Over: Larimer Co. Canal No. 2
0.1 Mi E of Meadowlark Av, Larimer, CO
Over: Greeley Loveland Canal
100 Ft N of 1st St, Larimer, CO
Over: Home Supply Ditch
0.2 Mi E of Co Rd 23, Larimer, CO
Over: CO.RD 82 BUCKEYE ROAD
11.3 MI SOUTH OF WYOMING, Larimer, CO
Over: I 25 ML
1.5 MI N OF SH 1, Larimer, CO
Over: Little Thompson River
0.7 Mi N of Co Rd 2E, Larimer, CO
Over: Cache La Poudre River
0.7 M W of Jct US Hwy 287, Larimer, CO
Over: WINDSOR RES CANAL SR
1.6 MI N OF JCT SH 14, Larimer, CO
Over: HOME SUPPLY DITCH
3.5 MI W OF LOVELAND, Larimer, CO
Over: Fall River
80 Ft W of US Hwy 34, Larimer, CO
Over: Fall River
100 Ft S of US Hwy 34, Larimer, CO
Over: Poudre Valley Canal
1.3 Mi N of Co Rd 60E, Larimer, CO
Over: Larimer County Canal
2.0 Mi N of Co Rd 56, Larimer, CO
Over: LAKE CANAL
At Woodlawn Dr., Larimer, CO
Over: Joe Wright Creek
100 Ft N of St Hwy 14, Larimer, CO
Over: Poudre Valley Canal
0.1 Mi East of I-25, Larimer, CO
Over: N FK BIG THOMPSON RIVER
11.7 MI E OF ESTES PARK, Larimer, CO
Over: FALL RIVER
W SIDE OF ESTES PARK, Larimer, CO
Over: Cache La Poudre River
0.1 Mi E of Co Rd 23, Larimer, CO
Over: FALL RIVER
US 34 BUS. IN ESTES PARK, Larimer, CO
Over: S Frk Cache La Poudre Rv
4.1 Mi N of Co Rd 44H, Larimer, CO
Over: Dry Creek
1.8 Mi E of Co Rd 31, Larimer, CO
Over: Little Thompson River
0.2 Mi N of Co Rd 4F, Larimer, CO
Over: Fossil Creek Res. Inlet
Jct. with Co Rd 9, Larimer, CO
Over: CANAL CATTLE UNDERPASS
12 MILES NORTH OF TEDS PL, Larimer, CO
Over: Big Thompson River
1.2 Mi N of Co Rd 18, Larimer, CO
Over: Fall River
200 Ft SW of US Hwy 34, Larimer, CO
Over: Larimer Co. Canal No. 2
20 Ft. E of Lynnwood St., Larimer, CO
Over: Cottonwood Creek
0.1 Mi S of Co Rd 18E, Larimer, CO
Over: Box Elder Creek
100 Ft E of Co Rd 9, Larimer, CO
Over: SPRING CREEK
FORT COLLINS, Larimer, CO
Over: LARIMER COUNTY CANAL SR
5 MI N OF JCT SH 14, Larimer, CO
Over: Laramie River
6.0 Mi North of St Hwy 14, Larimer, CO
Over: Louden Ditch
0.2 Mi N of Co Rd 24, Larimer, CO
Over: LARIMER CO CANAL
2.2 MI N OF FT COLLINS, Larimer, CO
Over: LOUDEN DITCH
2.2 M. WEST OF LOVELAND, Larimer, CO
Over: N. Poudre Canal/Park Cr.
4.9 Mi E of US Hwy 287, Larimer, CO
Over: I 25 ML
I-25 WELLINGTON INTER., Larimer, CO
Over: BIG THOMPSON RIVER
1.5 MI E OF ESTES PARK, Larimer, CO
Over: FRONTAGE ROAD
9.9 MI S OF WYOMING S.L., Larimer, CO
Over: FRONTAGE ROAD
8.6 MI S OF WYOMING S.L., Larimer, CO
Over: FRONTAGE ROAD
7.6 MI S OF WYOMING S.L., Larimer, CO
Over: LARIMER COUNTY CANAL
5.2 MI N OF JCT SH 14, Larimer, CO
Over: Lake Canal
.2 Mi S of CR 38, Larimer, CO
Over: LARIMER COUNTY CANAL SR
5 MI N OF JCT 14/E of I25, Larimer, CO
Read our methodology - how this data is sourced, computed, and verified.
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.