Colorado Bridges

8,965 highway bridges across 64 counties · NBI 2024 data

4.8% in poor condition
National avg: 6.8%
3,197
5,336
432
Good: 3,197 (35.7%) Fair: 5,336 (59.5%) Poor: 432 (4.8%)

About Colorado's Bridge Infrastructure

Colorado maintains 8,965 highway bridges across 64 counties, forming critical links in the state's transportation network. With an average construction year of 1982, the typical bridge in Colorado is approximately 44 years old—5 years newer than the national average of 49 years. The state's oldest bridge dates back to 1887, representing over a century of service and offering a window into historic bridge engineering practices.

Currently, 4.8% of Colorado's bridges are rated in poor condition, better than the national average of 6.8%. This indicates relatively strong investment in bridge maintenance and replacement programs. A "poor" condition rating indicates significant deterioration requiring attention, though these bridges remain safe for travel at their posted limits. Federal regulations require bridge inspections at least every 24 months to ensure public safety.

Bridge conditions in Colorado reflect decades of infrastructure investment decisions shaped by geography, climate, traffic demands, and available funding. Bridges here carry 9,663 vehicles daily on average—21% higher than the national average—placing greater demands on structural maintenance. The state's 86,348,671 total daily bridge crossings underscore how essential this infrastructure is to daily commerce and commuting.

The material composition of Colorado's bridge inventory reflects regional construction practices and evolving engineering standards. The predominant construction material is steel, accounting for 32.4% of all structures. Material choice affects maintenance requirements, expected lifespan, and vulnerability to environmental factors specific to the region. Understanding these patterns helps transportation planners allocate resources effectively and prioritize infrastructure investments.

432 of 8,965 Colorado bridges have a rating of 4 or below. Rating 4 = advanced deterioration.

#BridgeRatingLocationBuiltDaily Traffic
1144TH AVENUE
over LOST CREEK
Critical condition requiring immediate attention. Built 66 years ago, approaching the end of typical service life.
0
Adams County Co. · 1.2 MILES WEST OF SH 791960
2County Road 79.0
over Salado Creek
Critical condition requiring immediate attention. Low-traffic rural crossing.
0
Las Animas County Co. · 2.8 Mi N of CR 6420202
3County Road GG
over Hell Creek
Critical condition requiring immediate attention. Low-traffic rural crossing.
0
Washington County Co. · 1.9 Mi. N. of Co. Rd. 2719858
4SH6 DITCH RIDER RD
over BURLINGTON CANAL SR
Critical condition requiring immediate attention. Built 78 years ago, approaching the end of typical service life. Serves 19,000 vehicles per day.
1
Adams County Co. · 0.7 MI N OF JCT SH 224194819,000
5COUNTY ROAD 27
over ARKANSAS RIVER
Critical condition requiring immediate attention. At 119 years old, this is among Colorado's oldest structures. Low-traffic rural crossing.
1
Fremont County Co. · .1 MI N OF US 50190741
6SLATE RIVER ROAD
over NO DATA ENTERED
Critical condition requiring immediate attention. Low-traffic rural crossing.
2
Gunnison County Co. · 8 MILES NW CRESTED BUTTE200615
7FOREST ROAD 305
over M THOMPSON CR
Critical condition requiring immediate attention. Built 70 years ago, approaching the end of typical service life. Low-traffic rural crossing.
2
Pitkin County Co. · 7.8 MI SW OF CARBONDALE195610
8COUNTY ROAD 191
over ARKANSAS RIVER
Critical condition requiring immediate attention. At 118 years old, this is among Colorado's oldest structures.
2
Chaffee County Co. · .3 MI E of SH 2911908
9FDR 360
over SOUTH FORK
Serious deterioration affecting structural elements.
3
Rio Grande County Co. · 1.2 MI SW OF SOUTH FORK1976738
10HOLZWARTH ACCESS R
over COLORADO RIVER
Serious deterioration affecting structural elements. Low-traffic rural crossing.
3
Grand County Co. · West side of park approx19822

Bridges by County

El Paso County holds 8% of Colorado's bridges. Las Animas County has the highest deficiency rate.

CountyBridgesConditionPoorPoor %Avg ADT
El Paso County
Largest bridge inventory in Colorado.
686
245
408
223.2%14,394
Weld County
One of Colorado's largest bridge inventories.
614
219
365
294.7%6,419
Larimer County
One of Colorado's largest bridge inventories. Below-average deficiency rate.
559
200
333
112.0%7,343
Adams County
High-traffic area averaging 21,074 vehicles per bridge daily.
535
191
318
37
376.9%21,074
Jefferson County464
166
276
29
296.2%18,194
Denver County
Below-average deficiency rate. High-traffic area averaging 40,997 vehicles per bridge daily.
458
164
273
81.7%40,997
Arapahoe County
Poor condition rate significantly above state average.
391
140
233
28
287.2%19,656
Mesa County
Below-average deficiency rate.
319
114
190
51.6%4,717
Boulder County
Below-average deficiency rate.
311
111
185
72.3%10,249
Pueblo County264
94
157
124.5%8,361

Infrastructure Profile

Key Metrics
Average bridge age44 years
Average year built1982
Oldest bridge1887
Newest bridge2024
Avg daily traffic/bridge9,663
Total daily crossings86.3M
Rating Distribution (0–9 scale)
0–4 = Poor · 5–6 = Fair · 7–9 = Good
Construction Materials
Steel2,906(32.4%)
Prestressed Concrete2,848(31.8%)
Concrete2,810(31.3%)
Wood/Timber285(3.2%)
Metal (Other)82(0.9%)
Masonry30(0.3%)
Other4(0.0%)

Colorado vs. National Average

Poor Condition
4.8%
National: 6.8%✓ Better
Good Condition
35.7%
National: 44.1%✗ Worse
Average Age
44 yr
National: 49 yr✓ Better
Avg Daily Traffic
9,663
National: 7,954✓ Better
Data Source: Federal Highway Administration, National Bridge Inventory 2024. Bridge conditions rated 0–9 per FHWA Recording and Coding Guide. "Poor" = rating ≤ 4 on deck, superstructure, substructure, or culvert.
Inspections typically occur every 24 months. Structurally deficient does not mean unsafe.
Colorado Bridges — 8,965 Bridges, 4.8% Poor | BridgeReport.org