Total bridges
174
Public highway bridges in San Juan County
County profile · official public datasets
San Juan County, NM
174 public highway bridges tracked in the FHWA National Bridge Inventory: 36.8% rated Good, 56.9% Fair, 6.3% Poor.
- 174
- Public bridges
- 36.8%
- Good condition
- 6.3%
- Poor condition
The verdict
According to the Federal Highway Administration's 2024 National Bridge Inventory.
San Juan County posts a higher-than-median Poor-condition share among rated counties in the state across mid-size county bridge inventory.
- 24th
- of 32 on Poor share
- 6.3%
- Poor-condition share
- 174
- public highway bridges
- 1977
- 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 Juan County Bridge Snapshot
According to the Federal Highway Administration's 2024 National Bridge Inventory, San Juan County ranks #24 of 32 New Mexico counties with at least 5 public highway bridges on Poor-condition share (lower share ranks better; currently 6.3%). San Juan County, New Mexico contains 174 public highway bridges. Roughly 36.8% are rated “Good,” 56.9% “Fair,” and 6.3% “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
36.8%
64 of 174 rated 7-9
Fair condition
56.9%
99 of 174 rated 5-6
Poor condition
6.3%
11 of 174 rated 4 or below
In-state Poor-share rank
#24 of 32
Among New Mexico counties with 5+ bridges, lower share ranks better
Condition distribution
Share of 174 NBI-tracked bridges by lowest applicable component rating.
Good 36.8% (64)
Fair 56.9% (99)
Poor 6.3% (11)
San Juan County's Poor-condition bridges carry 27,547 vehicle crossings a day
That is 2.7% of the county's reported daily bridge traffic on 6.3% of its bridges: Poor-condition structures carry less traffic than their share of the inventory. Each Poor bridge averages 2,504 crossings a day against 5,347 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 174 of 174 bridges in this county that report an average daily traffic count. Source: FHWA National Bridge Inventory, 2024 release.
35.6% of San Juan County's bridges have passed the 50-year mark
62 of the 174 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 36.8% 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 59.6% of the county's Poor-condition bridge traffic
IRR/US64/491 WBL over SAN JUAN RIVER, built 1936, carries 16,419 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 27,547 daily crossings on Poor-rated bridges that report a traffic count. Source: FHWA National Bridge Inventory, 2024 release.
When San Juan County's bridges were built
174 bridges with a recorded construction year, grouped by decade
- 1920s 3
1920–1929
3 bridges
- 1930s 9
1930–1939
9 bridges
- 1940s 9
1940–1949
9 bridges
- 1950s 13
1950–1959
13 bridges
- 1960s
1960–1969
20 bridges
- 1970s
1970–1979
49 bridges
- 1980s
1980–1989
26 bridges
- 1990s 14
1990–1999
14 bridges
- 2000s 17
2000–2009
17 bridges
- 2010s 12
2010–2019
12 bridges
- 2020s 2
2020–2029
2 bridges
What this shows Construction peaked in the 1970s, when 49 of the county's bridges still in the inventory were built, which is 28.2% of those with a recorded year. That cohort is now 45 to 54 years old in the 2024 inventory. Its average build year (1977) matches the New Mexico average (1973).
How San Juan County compares with New Mexico's closest counties by inventory size
The 5 New Mexico counties nearest San Juan County in number of bridges, with their condition splits. Its 6.3% Poor share is the 4th-lowest of these 6. Its average build year of 1977 against a peer-group mean of 1971 is 6 years newer.
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 | 175 | 41.1% | 50.9% | 8% | 1972 |
| San Juan County (this page) | 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 Juan 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 Juan County, both outside New Mexico so the neighborhoods are not the same-state size table above.
Similar inventory size
Nearest county inventories outside NM (174 bridges here).
- Hempstead County, AR · 174 bridges
- Eagle County, CO · 174 bridges
- Washington County, IN · 174 bridges
- Lac qui Parle County, MN · 174 bridges
Similar average build year
Nearest mean year-built outside NM (1977 here).
- San Diego County, CA · avg 1977 · 1,632 bridges
- King County, WA · avg 1977 · 1,238 bridges
- Riverside County, CA · avg 1977 · 1,117 bridges
- Shelby County, TN · avg 1977 · 1,077 bridges
Source: FHWA National Bridge Inventory, 2024 release. Peers floor at 10 bridges so stub inventories cannot own the match.
All bridges (174)
STATE HIGHWAY 57
FairOver: CHACO WASH
NEAR FAJADA BUTTE., San Juan, NM
Built 1975 Load: 15.4 t ADT: 200
New Mexico Rd 511
FairOver: Navajo Dam Spillway
25 mi E of Farmington NM, San Juan, NM
Built 1942 Load: 22.0 t ADT: 800
NM-371
FairOver: SAN JUAN RIVER
0.8 MI S OF US-64/FRMGTON, San Juan, NM
Built 1996 Load: 23.7 t ADT: 13,898
45-Z003
FairOver: BOHANAN ARROYO
3.8 MI N OF JCT NM 516, San Juan, NM
Built 1941 Load: 24.3 t ADT: 1,297
NM-516
FairOver: UNNAMED WATERWAY
4.3 MI N OF JCT US 64, San Juan, NM
Built 1937 Load: 24.3 t ADT: 28,871
NM-516
FairOver: UNNAMED WATERWAY
3.6 MI NE OF BROWING PRKW, San Juan, NM
Built 1937 Load: 24.3 t ADT: 21,732
NM-516
FairOver: UNNAMED WATERWAY
4.0 MI N OF BROWING PRKWY, San Juan, NM
Built 1937 Load: 24.3 t ADT: 21,732
NM-170
FairOver: LA PLATA RIVER
2.7 MI N OF JCT NM-574, San Juan, NM
Built 1955 Load: 24.3 t ADT: 3,268
IRR/US-64
FairOver: RED WASH
14.2 MI W OF JCT US-491, San Juan, NM
Built 1960 Load: 24.3 t ADT: 4,536
US-550 SBL
FairOver: HAMPTON ARROYO
0.70 MI N OF JCT NM 516, San Juan, NM
Built 1961 Load: 25.1 t ADT: 14,956
US-550 NBL
FairOver: HAMPTON ARROYO
0.70 MI NORTH JCT NM-516, San Juan, NM
Built 1961 Load: 25.1 t ADT: 14,956
US-550
FairOver: KUTZ CANYON
2.9 MI S OF JCT US 64, San Juan, NM
Built 1947 Load: 25.8 t ADT: 6,326
45-6675
FairOver: STEVENS ARROYO
0.5 MI S US-64 @ MP-39.8, San Juan, NM
Built 1957 Load: 26.3 t ADT: 1,925
US-64
FairOver: SAN JUAN RIVER
1.6 MI W OF NM-511, San Juan, NM
Built 1996 Load: 26.6 t ADT: 2,283
NM-516
FairOver: NORTH FARMINGTON DITCH
2.15 MI N JCT US64/NM-516, San Juan, NM
Built 1985 Load: 27.8 t ADT: 20,831
US-64/491 EBL
FairOver: SAN JUAN RIVER
US-64 Shiprock, San Juan, NM
Built 1975 Load: 27.9 t ADT: 16,419
IRR BIA RTE N4055
FairOver: GAAGII WASH
7.2M S 4.0M W FARMINGTON, San Juan, NM
Built 1985 Load: 29.2 t ADT: 269
IRR/US-64
FairOver: SHIPROCK WASH
7.9 MI W OF JCT US-491, San Juan, NM
Built 1956 Load: 29.3 t ADT: 4,536
IRR BIA RTE N5001
FairOver: CLAH WASH
4.0M E 0.5M S TOADLENA TP, San Juan, NM
Built 1978 Load: 29.9 t ADT: 127
45-3500
FairOver: FLORA VISTA ARROYO
0.3 MI S NM 516, San Juan, NM
Built 1967 Load: 31.7 t ADT: 623
US-550
FairOver: SAN JUAN RIVER
0.7 Mi S of Jct US-64, San Juan, NM
Built 1947 Load: 32.2 t ADT: 6,326
US-64
FairOver: BAKER ARROYO
0.60 MI E OF JCT US 491, San Juan, NM
Built 1936 Load: 32.4 t ADT: 14,873
45Z004
FairOver: UNNAMED WATERWAY
0.45 MI WEST JCT US 550, San Juan, NM
Built 1952 Load: 32.4 t ADT: 3,676
US-64 EBL/WBL
FairOver: UNNAMED WATERWAY
10.01 M E OF JCT US-550, San Juan, NM
Built 1936 Load: 32.4 t ADT: 14,873
NM-516
FairOver: UNNAMED WATERWAY
3.1 MI N OF JCT US 64, San Juan, NM
Built 1937 Load: 32.4 t ADT: 36,708
NM-516
FairOver: UNNAMED WATERWAY
5.0 MI N OF BROWING PRKWY, San Juan, NM
Built 1937 Load: 32.4 t ADT: 21,732
US-550
FairOver: UNNAMED WATERWAY
7.0 MI N OF US 64, San Juan, NM
Built 1946 Load: 32.4 t ADT: 9,219
US-64 EBL/WBL
FairOver: UNNAMED WATERWAY
5.10 MI W OF JCT NM-170, San Juan, NM
Built 1956 Load: 32.4 t ADT: 18,125
IRR/US-64
FairOver: SHOE GAME WASH
NEW MEX./ARIZ STATE LINE, San Juan, NM
Built 1956 Load: 32.4 t ADT: 4,536
NM-516
FairOver: UNNAMED WATERWAY
2.40 MI W OF US-550, San Juan, NM
Built 1958 Load: 32.4 t ADT: 19,020
NM-516 WB
FairOver: ANIMAS RIVER
0.1 MI N OF NM-248/AZTEC, San Juan, NM
Built 1960 Load: 32.4 t ADT: 16,254
NM-516 EB
FairOver: ANIMAS RIVER
0.1 MI W Jct US550/AZTEC, San Juan, NM
Built 1960 Load: 32.4 t ADT: 16,254
FL-4192/Aztec Ruin
FairOver: AZTEC ARROYO
0.1 MI N OF JCT NM-516, San Juan, NM
Built 1960 Load: 32.4 t ADT: 1,297
US-64
FairOver: UNNAMED WATERWAY
0.7 MI W OF US550/BLOOMFL, San Juan, NM
Built 1966 Load: 32.4 t ADT: 14,291
US-491
FairOver: MALPAIS ARROYO
US 491 MM 102.01, San Juan, NM
Built 1969 Load: 32.4 t ADT: 4,089
IRR/US-491
FairOver: UNNAMED WATERWAY
38.8 MI N OF JCT I-40, San Juan, NM
Built 1973 Load: 32.4 t ADT: 5,746
IRR/US-491
FairOver: UNNAMED WATERWAY
40.3 MI N OF JCT I-40, San Juan, NM
Built 1973 Load: 32.4 t ADT: 5,746
US-64
FairOver: GLADE ARROYO
W JCT MAIN & BROADWAY, San Juan, NM
Built 1974 Load: 32.4 t ADT: 15,167
US-64 EBL/WBL
FairOver: UNNAMED WATERWAY
3.48 MI W OF JCT NM-170, San Juan, NM
Built 1975 Load: 32.4 t ADT: 19,991
IRR/US-491
FairOver: UNNAMED WATERWAY
43.2 MI N OF JCT I-40, San Juan, NM
Built 1975 Load: 32.4 t ADT: 5,746
IRR/US-491
FairOver: NASCHITTI WASH
41.3 MI N OF JCT I-40, San Juan, NM
Built 1975 Load: 32.4 t ADT: 5,746
NM-173
FairOver: PUMP CANYON
3.11 MI W OF JCT NM-511, San Juan, NM
Built 1977 Load: 32.4 t ADT: 558
IRR/US-491
FairOver: YELLOW ARROYO
5.3 MI N OF JCT US-64, San Juan, NM
Built 1978 Load: 32.4 t ADT: 4,089
US-491
FairOver: MALPAS ARROYO
8.3 MI N OF JCT US-64, San Juan, NM
Built 1978 Load: 32.4 t ADT: 4,089
US-64
FairOver: ANIMAS RIVER
.1 MI E Broadway/Scott Av, San Juan, NM
Built 1958 Load: 32.4 t ADT: 7,060
FL-4385
FairOver: GLADE ARROYO
0.2 MI N MAIN ST/FARMINGT, San Juan, NM
Built 1977 Load: 32.4 t ADT: 4,178
45-3000
FairOver: HAMPTON ARROYO
SABENA ST. IN AZTEC, San Juan, NM
Built 1973 Load: 32.4 t ADT: 623
US-64
FairOver: VAUGHN ARROYO
11.78 MI E OF JCT US-491, San Juan, NM
Built 1979 Load: 32.4 t ADT: 14,873
NM-516
FairOver: ANIMAS RIVER
1.7 MI N JCT US64/NM-516, San Juan, NM
Built 1985 Load: 32.4 t ADT: 20,831
45-7900
FairOver: ESCAVADA WASH
8.6 MI S OF JCT US 550, San Juan, NM
Built 1987 Load: 32.4 t ADT: 642
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.