Total bridges
175
Public highway bridges in San Miguel County
County profile · official public datasets
San Miguel County, NM
175 public highway bridges tracked in the FHWA National Bridge Inventory: 41.1% rated Good, 50.9% Fair, 8% Poor.
- 175
- Public bridges
- 41.1%
- Good condition
- 8%
- Poor condition
The verdict
According to the Federal Highway Administration's 2024 National Bridge Inventory.
San Miguel County posts a higher-than-median Poor-condition share among rated counties in the state across mid-size county bridge inventory.
- 28th
- of 32 on Poor share
- 8%
- Poor-condition share
- 175
- public highway bridges
- 1972
- 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.
San Miguel County Bridge Snapshot
According to the Federal Highway Administration's 2024 National Bridge Inventory, San Miguel County ranks #28 of 32 New Mexico counties with at least 5 public highway bridges on Poor-condition share (lower share ranks better; currently 8%). San Miguel County, New Mexico contains 175 public highway bridges. Roughly 41.1% are rated “Good,” 50.9% “Fair,” and 8% “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
41.1%
72 of 175 rated 7-9
Fair condition
50.9%
89 of 175 rated 5-6
Poor condition
8%
14 of 175 rated 4 or below
In-state Poor-share rank
#28 of 32
Among New Mexico counties with 5+ bridges, lower share ranks better
Condition distribution
Share of 175 NBI-tracked bridges by lowest applicable component rating.
Good 41.1% (72)
Fair 50.9% (89)
Poor 8% (14)
San Miguel County's Poor-condition bridges carry 6,735 vehicle crossings a day
That is 1.5% of the county's reported daily bridge traffic on 8% of its bridges: Poor-condition structures carry less traffic than their share of the inventory. Each Poor bridge averages 481 crossings a day against 2,274 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 175 of 175 bridges in this county that report an average daily traffic count. Source: FHWA National Bridge Inventory, 2024 release.
52% of San Miguel County's bridges have passed the 50-year mark
91 of the 175 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 41.1% 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 35.5% of the county's Poor-condition bridge traffic
US-84 over I-25 NBL/SBL, built 1966, carries 2,388 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 14-bridge count understates how much of the daily burden sits on a single crossing.
Share is of the 6,735 daily crossings on Poor-rated bridges that report a traffic count. Source: FHWA National Bridge Inventory, 2024 release.
When San Miguel County's bridges were built
175 bridges with a recorded construction year, grouped by decade
- 1900s 1
1900–1909
1 bridges
- 1910s 3
1910–1919
3 bridges
- 1920s 1
1920–1929
1 bridges
- 1930s 7
1930–1939
7 bridges
- 1940s
1940–1949
20 bridges
- 1950s
1950–1959
16 bridges
- 1960s
1960–1969
31 bridges
- 1970s
1970–1979
24 bridges
- 1980s
1980–1989
40 bridges
- 1990s 11
1990–1999
11 bridges
- 2000s 11
2000–2009
11 bridges
- 2010s 9
2010–2019
9 bridges
- 2020s 1
2020–2029
1 bridges
What this shows Construction peaked in the 1980s, when 40 of the county's bridges still in the inventory were built, which is 22.9% of those with a recorded year. That cohort is now 35 to 44 years old in the 2024 inventory. Its average build year (1972) matches the New Mexico average (1973).
How San Miguel County compares with New Mexico's closest counties by inventory size
The 5 New Mexico counties nearest San Miguel County in number of bridges, with their condition splits. Its 8% Poor share is the 6th-lowest of these 6. Its average build year of 1972 against a peer-group mean of 1972 is in line with the group.
Showing the 5 closest of 31 New Mexico counties eligible for comparison.
| County | Bridges | Good | Fair | Poor | Avg. built |
|---|---|---|---|---|---|
| Socorro County | 188 | 16.5% | 76.1% | 7.4% | 1961 |
| Sandoval County | 182 | 40.7% | 54.4% | 4.9% | 1979 |
| San Miguel County (this page) | 175 | 41.1% | 50.9% | 8% | 1972 |
| San Juan County | 174 | 36.8% | 56.9% | 6.3% | 1977 |
| Rio Arriba County | 160 | 47.5% | 46.3% | 6.3% | 1973 |
| Colfax County | 140 | 37.9% | 57.1% | 5% | 1969 |
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 San Miguel 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 San Miguel County, both outside New Mexico so the neighborhoods are not the same-state size table above.
Similar inventory size
Nearest county inventories outside NM (175 bridges here).
- Smith County, MS · 175 bridges
- Warren County, MS · 175 bridges
- Hamilton County, NE · 175 bridges
- Madison County, NY · 175 bridges
Similar average build year
Nearest mean year-built outside NM (1972 here).
- Santa Clara County, CA · avg 1972 · 964 bridges
- Madison County, AL · avg 1972 · 710 bridges
- Kern County, CA · avg 1972 · 668 bridges
- York County, PA · avg 1972 · 569 bridges
Source: FHWA National Bridge Inventory, 2024 release. Peers floor at 10 bridges so stub inventories cannot own the match.
Fair-condition bridges (89)
State Hwy 433
FairOver: South Canadian River
Conchas Dam, San Miguel, NM
Built 1940 Load: 11.7 t ADT: 150
New Mexico Ave
FairOver: LA MANTECA ARROYO
0.12 MI N. OF JCT NM-329, San Miguel, NM
Built 1912 Load: 13.0 t ADT: 192
47-A19A
FairOver: TECOLOTE CREEK
0.95 MI S OF NM-283, San Miguel, NM
Built 1980 Load: 13.6 t ADT: 198
FDR 263
FairOver: GALLINAS RIVER
3.5 MI NW/O E.V.LONG CG, San Miguel, NM
Built 1958 Load: 15.9 t ADT: 100
FDR 122
FairOver: HOLY GHOST CREEK
1.138 MI NW/O NM 63 JCT, San Miguel, NM
Built 1939 Load: 16.2 t ADT: 250
FDR 122
FairOver: HOLY GHOST CREEK
0.121 MI NW/O NM 63 JCT, San Miguel, NM
Built 1939 Load: 18.1 t ADT: 250
FDR 263
FairOver: GALLINAS RIVER
3.9 NW/O E.V. LONG CG, San Miguel, NM
Built 1958 Load: 18.5 t ADT: 100
FDR 263
FairOver: GALLINAS RIVER
4.7 MI NW/O E.V. LONG CG, San Miguel, NM
Built 1965 Load: 18.8 t ADT: 100
47-B28A
FairOver: TRES HERMANOS CREEK
0.3 MI E OF I-25 FRNTG RD, San Miguel, NM
Built 1930 Load: 24.3 t ADT: 224
FR-2116
FairOver: UNNAMED WATERWAY
10.3 MI N OF JCT NM-3, San Miguel, NM
Built 1941 Load: 24.3 t ADT: 239
47-A04A
FairOver: CANADA DEL ROCIO
.67 MI W JCT NM-94 @ 3.9, San Miguel, NM
Built 1980 Load: 24.3 t ADT: 198
FORKED LIGHTNING R
FairOver: GLORIETA WASH
I-25 Exit 307. 3.7 miles, San Miguel, NM
Built 1950 Load: 24.5 t ADT: 2
NM-94
FairOver: MANUELITAS CREEK
3.3 MI NW OF JCT NM-518, San Miguel, NM
Built 1960 Load: 25.1 t ADT: 1,609
NM-223
FairOver: PECOS RIVER
0.3 MI E JCT NM-63/PECOS, San Miguel, NM
Built 1988 Load: 25.5 t ADT: 1,440
L-00015
FairOver: PECOS ARROYO
0.3 M S OF N VEGAS INTRCH, San Miguel, NM
Built 1947 Load: 25.9 t ADT: 4,795
FDR 122
FairOver: HOLY GHOST CREEK
0.291 NW/O 122/63 JCT, San Miguel, NM
Built 1939 Load: 25.9 t ADT: 250
FDR 122
FairOver: HOLY GHOST CREEK
0.157 MI NW/O NM 63, San Miguel, NM
Built 1939 Load: 26.2 t ADT: 250
NM-63
FairOver: RIO MORA
16.5 MI N OF JCT NM-223, San Miguel, NM
Built 1940 Load: 26.5 t ADT: 464
I-25 NBL
FairOver: RIO GALLINAS
1.5 MI S OF NM-104, San Miguel, NM
Built 1982 Load: 26.6 t ADT: 9,083
I-25 SBL
FairOver: RIO GALLINAS
1.5 MI S OF NM-104, San Miguel, NM
Built 1982 Load: 26.6 t ADT: 9,083
FDR 92
FairOver: COW CREEK
.7 MI N/O COW CREEK CG, San Miguel, NM
Built 1958 Load: 27.5 t ADT: 75
47-C53B
FairOver: UNNAMED WATERWAY
15.7 MI NE OF NM-104, San Miguel, NM
Built 1982 Load: 27.8 t ADT: 198
NM-283
FairOver: I-25 NBL/SBL
0.9 M S OF S VEGAS INTRCH, San Miguel, NM
Built 1973 Load: 29.4 t ADT: 422
47B059
FairOver: PECOS RIVER
.05 MI W OF NM-3 @MP-62.4, San Miguel, NM
Built 1988 Load: 29.9 t ADT: 198
US-84
FairOver: UNNAMED WATERWAY
13.2 MI S I-25, San Miguel, NM
Built 1940 Load: 30.8 t ADT: 2,388
NM-419
FairOver: LA CINTA CREEK
37.0 MI N OF NM-104, San Miguel, NM
Built 1978 Load: 30.9 t ADT: 43
I-25 NB
FairOver: Pecos River
1.7 Mi S of Jct NM-3, San Miguel, NM
Built 1966 Load: 31.5 t ADT: 9,215
I-25 SB
FairOver: Pecos River
1.7 Mi S of Jct NM-3, San Miguel, NM
Built 1966 Load: 31.5 t ADT: 9,215
I-25 NBL
FairOver: I-25 SERVICE ROAD
4.4 Mi S US-84/Romerovill, San Miguel, NM
Built 1966 Load: 31.5 t ADT: 10,556
I-25 SBL
FairOver: Frontage Rd/FR2135
4.4 Mi S US-84/Romerovill, San Miguel, NM
Built 1966 Load: 31.5 t ADT: 8,817
NM-419
FairOver: TREMENTINA CREEK
4.5 MI N OF NM-104, San Miguel, NM
Built 1984 Load: 31.8 t ADT: 43
FL-4658
FairOver: GALLINAS RIVER
0.1 MI W OF 12TH STREET, San Miguel, NM
Built 1909 Load: 32.4 t ADT: 6,264
FL-5663
FairOver: PAJARITO ARROYO
0.1 MI N OF INDEPENDENCE, San Miguel, NM
Built 1911 Load: 32.4 t ADT: 2,002
NM-518
FairOver: SAN GUIJUELA ARROYO
1.2 MI S OF JCT NM-266, San Miguel, NM
Built 1939 Load: 32.4 t ADT: 3,490
FR-2116
FairOver: UNNAMED WATERWAY
0.1 MI N OF JCT NM-3, San Miguel, NM
Built 1941 Load: 32.4 t ADT: 239
FL-5661
FairOver: ARROYO HERMANOS
0.1 MI N OF VALENCIA ST, San Miguel, NM
Built 1911 Load: 32.4 t ADT: 1,451
NM-63
FairOver: PECOS RIVER
0.9 MI N OF JCT NM-223, San Miguel, NM
Built 1963 Load: 32.4 t ADT: 2,487
NM-63
FairOver: PECOS RIVER
6.2 MI N OF JCT NM-223, San Miguel, NM
Built 1963 Load: 32.4 t ADT: 730
FR-2123
FairOver: I-25 NBS/SBL
2.7 Mi S of Jct NM-3, San Miguel, NM
Built 1966 Load: 32.4 t ADT: 644
FR-2130
FairOver: I-25 NBLS/SBLS
27.1 Mi N of Santa Fe C/L, San Miguel, NM
Built 1966 Load: 32.4 t ADT: 522
NM-63
FairOver: PECOS RIVER
15.5 MI N OF JCT I-25, San Miguel, NM
Built 1967 Load: 32.4 t ADT: 561
NM-63
FairOver: PECOS RIVER
16.37 MI N OF JCT I-25, San Miguel, NM
Built 1967 Load: 32.4 t ADT: 561
I-25 NBL/SBL/FRTG
FairOver: UNNAMED WATERWAY
15.1 MI N OF SANTA FE C/L, San Miguel, NM
Built 1966 Load: 32.4 t ADT: 9,224
I-25 NBL/SBL/FRTG
FairOver: UNNAMED WATERWAY
29.3 MI N OF SANTA FE C/L, San Miguel, NM
Built 1966 Load: 32.4 t ADT: 9,714
I-25 NBL/SBL
FairOver: LOCAL RURAL ROAD
21.7 M N US-84/ROMEROVLLE, San Miguel, NM
Built 1967 Load: 32.4 t ADT: 7,120
I-25 NBL
FairOver: UNNAMED WATERWAY
8.3 MI N OF NM-104/VEGAS, San Miguel, NM
Built 1967 Load: 32.4 t ADT: 6,897
I-25 NBL/SBL
FairOver: LOCAL RURAL ROAD
ONAVA I/C EXIT 356, San Miguel, NM
Built 1967 Load: 32.4 t ADT: 6,959
I-25 NBL/SBL/FRNTG
FairOver: UNNAMED WATERWAY
0.5 MI N OF JCT US-84, San Miguel, NM
Built 1966 Load: 32.4 t ADT: 11,619
NM-104
FairOver: I-25/R/R/CITY ST/WATERWY
0.2 MI E OF LOOP-15, San Miguel, NM
Built 1982 Load: 32.4 t ADT: 4,042
47-004
FairOver: UNNAMED WATERWAY
0.1 MI W OF NM-94 @MP-3.9, San Miguel, NM
Built 1974 Load: 32.4 t ADT: 198
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.