County profile · official public datasets

Larimer County, CO

559 public highway bridges tracked in the FHWA National Bridge Inventory: 49% rated Good, 49% Fair, 2% Poor.

559
Public bridges
49%
Good condition
2%
Poor condition

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.

Top 25%
lowest Poor share in state
2%
Poor-condition share
559
public highway bridges
1987
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.

Larimer County Bridge Snapshot

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

Condition distribution

Share of 559 NBI-tracked bridges by lowest applicable component rating.

Good
49% (274)
Fair
49% (274)
Poor
2% (11)

Larimer County's Poor-condition bridges carry 57,230 vehicle crossings a day

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.

28.8% of Larimer County's bridges have passed the 50-year mark

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.

One structure carries 33.2% of the county's Poor-condition bridge traffic

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.

When Larimer County's bridges were built

559 bridges with a recorded construction year, grouped by decade

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.

Source FHWA National Bridge Inventory (year built) As of 2024 NBI release

How Larimer County compares with Colorado's closest counties by inventory size

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.

Bridge inventory size and condition shares for Larimer County and the 5 Colorado counties closest to it in inventory size
County Bridges Poor
El Paso County 686 3.2%
Weld County 614 4.7%
Larimer County (this page) 559 2%
Adams County 535 6.9%
Jefferson County 464 6.3%
Denver County 458 1.7%

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.

Nationwide counties with similar inventory size or average build year

Two NBI-derived peer sets for Larimer County, both outside Colorado so the neighborhoods are not the same-state size table above.

Similar inventory size

Nearest county inventories outside CO (559 bridges here).

Similar average build year

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.

All bridges (559)

County Road 21

Fair

Over: Little Thompson River

0.7 Mi N of S County Line, Larimer, CO

Built 1970 Load: 8.3 t ADT: 1,985

County Road 43H

Fair

Over: Little Thompson River

0.1 Mi N of Co Rd 45B, Larimer, CO

Built 1960 Load: 10.3 t ADT: 97

Taft Hill Rd(Cr17)

Fair

Over: Big Thompson River

0.2 Mi N of 1st Street, Larimer, CO

Built 1978 Load: 10.7 t ADT: 21,217

County Road 80C

Fair

Over: N Frk Cache La Poudre Rv

2.6 Mi W of Co Rd 59, Larimer, CO

Built 1965 Load: 11.1 t ADT: 118

County Road 15

Fair

Over: Boxelder Creek

0.8 Mi N of Co Rd 78, Larimer, CO

Built 1980 Load: 13.0 t ADT: 365

County Road 82

Fair

Over: Rawhide Creek

0.2 Mi E of Co Rd 15, Larimer, CO

Built 1980 Load: 13.0 t ADT: 363

County Road 21C

Fair

Over: Cache La Poudre River

0.2 Mi N of Co Rd 50E, Larimer, CO

Built 1976 Load: 13.2 t ADT: 3,333

BEAR LAKE ROAD

Fair

Over: BIG THOMPSON RIVER

1.9 MILES SOUTH OF BEAVER, Larimer, CO

Built 1960 Load: 14.5 t ADT: 2,500

County Road 82

Fair

Over: Coal Creek

0.3 Mi E of Co Rd 7, Larimer, CO

Built 1980 Load: 14.9 t ADT: 665

County Road 56

Fair

Over: Larimer County Canal

0.9 Mi E of Co Rd 11, Larimer, CO

Built 1966 Load: 16.4 t ADT: 168

County Road 76H

Fair

Over: N Frk Cache La Poudre Rv

1.0 Mi E of Co Rd 37, Larimer, CO

Built 1970 Load: 16.4 t ADT: 47

County Road 63E

Fair

Over: Cache La Poudre River

75 Ft S of St Hwy 14, Larimer, CO

Built 1934 Load: 16.6 t ADT: 240

Rainbow Trout LN

Fair

Over: Big Thompson River

25 Ft S of US Hwy 34, Larimer, CO

Built 1977 Load: 16.9 t ADT: 18

Cedar Cove Road

Fair

Over: Big Thompson River

0.2 Mi N of US Hwy 34, Larimer, CO

Built 1977 Load: 16.9 t ADT: 27

County Road 37

Fair

Over: Lone Pine Creek

0.2 Mi N of Co Rd 74E, Larimer, CO

Built 1981 Load: 17.1 t ADT: 96

WCR 3 LCR 1

Fair

Over: Cache La Poudre River

0.4 Mi S of St Hwy 392, Larimer, CO

Built 1977 Load: 17.1 t ADT: 11,943

US 287 ACCESS

Fair

Over: LOUDEN CANAL

3.5 MI N OF JCT US 34, Larimer, CO

Built 1950 Load: 17.5 t ADT: 52

River Rim Road

Fair

Over: Big Thompson River

20 Ft S of US Hwy 34, Larimer, CO

Built 1977 Load: 17.5 t ADT: 380

Rocky River Road

Fair

Over: Big Thompson River

40 Ft S of US Hwy 34, Larimer, CO

Built 1977 Load: 17.5 t ADT: 1

Rose Hall Way

Fair

Over: Big Thompson River

35 Ft S of US Hwy 34, Larimer, CO

Built 1977 Load: 17.5 t ADT: 11

US 287 ML

Fair

Over: LARIMER-WELD CANAL

0.2 MI S of SH1, Larimer, CO

Built 1949 Load: 17.6 t ADT: 24,000

County Road 52

Fair

Over: Larimer & Weld Canal

1.2 Mi East of I-25, Larimer, CO

Built 1975 Load: 17.7 t ADT: 706

HCL+PGL BRT Guide

Fair

Over: Mail Creek

100 ft S of W Co. Rd 38, Larimer, CO

Built 2019 Load: 17.8 t ADT: 295

Mountain River Rd

Fair

Over: Little Thompson River

50 ft S of W CR 4, Larimer, CO

Built 1936 Load: 18.4 t ADT: 42

FDR 155

Fair

Over: CACHE LA POUDRE RIVER

50 FT SOUTH OF CO HWY 114, Larimer, CO

Built 1937 Load: 18.8 t ADT: 100

County Road 9

Fair

Over: North Poudre Canal

1.5 Mi N of Co Rd 70, Larimer, CO

Built 1980 Load: 18.8 t ADT: 888

ASPENGLEN CAMPGROU

Fair

Over: FALL RIVER

0.2 MILES FROM FALL RIVER, Larimer, CO

Built 1983 Load: 19.0 t ADT: 300

County Road 80C

Fair

Over: N Frk Cache La Poudre Rv

0.5 Mi E of Co Rd 37, Larimer, CO

Built 1981 Load: 19.0 t ADT: 380

Big Pine Lane

Fair

Over: Big Thompson River

15 Ft S of US Hwy 34, Larimer, CO

Built 1977 Load: 19.0 t ADT: 18

I 25 ML NBND

Fair

Over: N.POUDRE DITCH SAND CRK

11.6 MI NORTH OF JCT SH 1, Larimer, CO

Built 1950 Load: 19.1 t ADT: 12,500

US 34 ML

Fair

Over: DRAW

3.8 MI W OF LOVELAND, Larimer, CO

Built 1933 Load: 20.2 t ADT: 4,900

County Road 25E

Fair

Over: Pleas Valley Lake Canal

1.3 Mi N of Co Rd 52E, Larimer, CO

Built 1963 Load: 20.4 t ADT: 347

County Road 54E

Fair

Over: Pleas. Valley Lake Canal

0.7 Mi E of Co Rd 27E, Larimer, CO

Built 1962 Load: 20.4 t ADT: 246

County Road 56

Fair

Over: Larimer County Canal

1.1 Mi E of I-25, Larimer, CO

Built 1940 Load: 20.4 t ADT: 221

County Road 103

Fair

Over: Larimer Poudre Canal

6.8 Mi N of St Hwy 14, Larimer, CO

Built 1954 Load: 20.6 t ADT: 85

County Road 19

Fair

Over: Poudre Valley Canal

50 Ft N of Co Rd 64, Larimer, CO

Built 1963 Load: 20.8 t ADT: 1,254

US 287 ML

Fair

Over: LOUDEN CANAL

3.2 MI N OF JCT US 34, Larimer, CO

Built 1924 Load: 21.0 t ADT: 34,000

US 287 ML

Fair

Over: SIX MILE CREEK

21.5 MILES NORTH OF TEDS, Larimer, CO

Built 1960 Load: 21.2 t ADT: 3,900

County Road 13E

Fair

Over: Jackson Ditch

0.2 Mi No of Co Rd 52C, Larimer, CO

Built 1962 Load: 21.5 t ADT: 315

County Road 32E

Fair

Over: Cache La Poudre River

0.1 Mi E of Co Rd 3, Larimer, CO

Built 1972 Load: 21.5 t ADT: 6,341

County Road 48

Fair

Over: Larimer & Weld Canal

0.8 Mi East of I-25, Larimer, CO

Built 1970 Load: 21.7 t ADT: 2,271

US 287 ML

Fair

Over: LARIMER COUNTY CANAL

FT COLLINS, Larimer, CO

Built 1948 Load: 21.8 t ADT: 37,000

SH 14 ML

Fair

Over: YOUNGS GULCH

13 MI EAST OF ROAD TO EGG, Larimer, CO

Built 1950 Load: 22.1 t ADT: 1,100

County Road 74E

Fair

Over: South Lone Pine Creek

9.9 Mi E of Co Rd 68C, Larimer, CO

Built 1967 Load: 22.1 t ADT: 2,242

Rustic Road

Fair

Over: Cache La Poudre River

Just S of CR14, Larimer, CO

Built 1959 Load: 22.1 t ADT: 81

US 287 ML

Fair

Over: BIG THOMPSON RIVER

0.4 MI N OF JCT SH 402, Larimer, CO

Built 1950 Load: 22.2 t ADT: 18,000

US 287 ML

Fair

Over: LARAMIE POUDRE CANAL

0.1 MI N OF JCT SH 14, Larimer, CO

Built 1965 Load: 22.5 t ADT: 6,500

County Road 74E

Fair

Over: N Frk Cache La Poudre Rv

1.9 MIi E of Co Rd 37, Larimer, CO

Built 1953 Load: 23.0 t ADT: 2,655

FT COLLINS EXP WAY

Fair

Over: DITCH

1.2 MI S OF TEDS PLACE, Larimer, CO

Built 1987 Load: 23.4 t ADT: 8,900

US 34 ML

Fair

Over: HANDY DITCH

3.7 MI WEST OF LOVELAND, Larimer, CO

Built 1933 Load: 23.5 t ADT: 4,900
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.