Total bridges
16
Public highway bridges in Alamosa County
County profile · official public datasets
Alamosa County, CO
16 public highway bridges tracked in the FHWA National Bridge Inventory: 37.5% rated Good, 62.5% Fair, 0% Poor.
- 16
- Public bridges
- 37.5%
- Good condition
- 0%
- Poor condition
The verdict
According to the Federal Highway Administration's 2024 National Bridge Inventory.
Alamosa County posts a top-10% lowest Poor-condition share among rated counties in the state across rated county bridge inventory.
- Top 9%
- lowest Poor share in state
- 0%
- Poor-condition share
- 16
- public highway bridges
- 1985
- 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.
Alamosa County Bridge Snapshot
According to the Federal Highway Administration's 2024 National Bridge Inventory, Alamosa County ranks #6 of 64 Colorado counties with at least 5 public highway bridges on Poor-condition share (lower share ranks better; currently 0%). Alamosa County, Colorado contains 16 public highway bridges. Roughly 37.5% are rated “Good,” 62.5% “Fair,” and 0% “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
37.5%
6 of 16 rated 7-9
Fair condition
62.5%
10 of 16 rated 5-6
Poor condition
0%
0 of 16 rated 4 or below
In-state Poor-share rank
#6 of 64
Among Colorado counties with 5+ bridges, lower share ranks better
Condition distribution
Share of 16 NBI-tracked bridges by lowest applicable component rating.
Good 37.5% (6)
Fair 62.5% (10)
Poor 0% (0)
25% of Alamosa County's bridges have passed the 50-year mark
4 of the 16 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 37.5% 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.
When Alamosa County's bridges were built
16 bridges with a recorded construction year, grouped by decade
- 1950s 2
1950–1959
2 bridges
- 1960s 2
1960–1969
2 bridges
- 1980s 2
1980–1989
2 bridges
- 1990s
1990–1999
9 bridges
- 2020s 1
2020–2029
1 bridges
What this shows Construction peaked in the 1990s, when 9 of the county's bridges still in the inventory were built, which is 56.3% of those with a recorded year. That cohort is now 25 to 34 years old in the 2024 inventory. Its average build year (1985) matches the Colorado average (1982).
How Alamosa County compares with Colorado's closest counties by inventory size
The 5 Colorado counties nearest Alamosa County in number of bridges, with their condition splits. Its 0% Poor share is the 3rd-lowest of these 6. Its average build year of 1985 against a peer-group mean of 1979 is 6 years newer.
Showing the 5 closest of 63 Colorado counties eligible for comparison.
| County | Bridges | Good | Fair | Poor | Avg. built |
|---|---|---|---|---|---|
| Mineral County | 26 | 34.6% | 65.4% | 0% | 1973 |
| Custer County | 20 | 45% | 50% | 5% | 1972 |
| Gilpin County | 19 | 10.5% | 89.5% | 0% | 1984 |
| Lake County | 17 | 52.9% | 35.3% | 11.8% | 1985 |
| Alamosa County (this page) | 16 | 37.5% | 62.5% | 0% | 1985 |
| San Juan County | 13 | 53.8% | 38.5% | 7.7% | 1981 |
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 Alamosa 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 Alamosa County, both outside Colorado so the neighborhoods are not the same-state size table above.
Similar inventory size
Nearest county inventories outside CO (16 bridges here).
- Aleutians East County, AK · 16 bridges
- North Slope County, AK · 16 bridges
- Grant County, KS · 16 bridges
- Cataño County, PR · 16 bridges
Similar average build year
Nearest mean year-built outside CO (1985 here).
- Hillsborough County, FL · avg 1985 · 840 bridges
- Lancaster County, NE · avg 1985 · 661 bridges
- Nueces County, TX · avg 1985 · 528 bridges
- Grayson County, TX · avg 1985 · 513 bridges
Source: FHWA National Bridge Inventory, 2024 release. Peers floor at 10 bridges so stub inventories cannot own the match.
Fair-condition bridges (10)
Access State Park
FairOver: Franklin Eddy Canal
San Luis State Park, Alamosa, CO
Built 1985 Load: 20.1 t ADT: 50
COUNTY ROAD 112
FairOver: LA JARA CREEK
7.2 MI SE OF ALAMOSA, Alamosa, CO
Built 1990 Load: 23.0 t ADT: 98
COUNTY ROAD 112
FairOver: ROCK CREEK
4.9 MI SE OF ALAMOSA, Alamosa, CO
Built 1990 Load: 23.2 t ADT: 121
US 160 ML
FairOver: RIO GRANDE
AT EAST END OF ALAMOSA, Alamosa, CO
Built 1966 Load: 26.1 t ADT: 13,000
CR 15 / 15 Mile Rd
FairOver: EMPIRE LATERAL
.2 MI S OF SH 370, Alamosa, CO
Built 1998 Load: 26.3 t ADT: 25
Co Rd 4 Mile Lane
FairOver: Hooper Lateral
.6 Mi E of CR 102, Alamosa, CO
Built 2021 Load: 34.3 t ADT: 41
STATE ST (CR 650)
FairOver: RIO GRANDE RIVER
.1 MI N OF 1ST ST, Alamosa, CO
Built 1982 Load: 39.4 t ADT: 1,994
SH 368 ML
FairOver: ALAMOSA FARM LATERL CANA
2.9 MI E OF JCT SH 371, Alamosa, CO
Built 1955 Load: 40.3 t ADT: 230
CNTY RD 2 MI LANE
FairOver: HOOPER LATERAL
.9 MI E OF CR 102, Alamosa, CO
Built 1995 Load: 44.8 t ADT: 50
COUNTY ROAD 108
FairOver: COSTILLA CANAL
2 MI W OF SH17, Alamosa, CO
Built 1997 Load: 75.6 t ADT: 49
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.