Total bridges
964
Public highway bridges in Santa Clara County
County profile · official public datasets
Santa Clara County, CA
964 public highway bridges tracked in the FHWA National Bridge Inventory: 38.3% rated Good, 56.1% Fair, 5.6% Poor.
- 964
- Public bridges
- 38.3%
- Good condition
- 5.6%
- Poor condition
The verdict
According to the Federal Highway Administration's 2024 National Bridge Inventory.
Santa Clara County posts a better-than-median Poor-condition share among rated counties in the state across large county bridge inventory.
- Top 31%
- lowest Poor share in state
- 5.6%
- Poor-condition share
- 964
- 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.
Santa Clara County Bridge Snapshot
According to the Federal Highway Administration's 2024 National Bridge Inventory, Santa Clara County ranks #18 of 58 California counties with at least 5 public highway bridges on Poor-condition share (lower share ranks better; currently 5.6%). Santa Clara County, California contains 964 public highway bridges. Roughly 38.3% are rated “Good,” 56.1% “Fair,” and 5.6% “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
38.3%
369 of 964 rated 7-9
Fair condition
56.1%
541 of 964 rated 5-6
Poor condition
5.6%
54 of 964 rated 4 or below
In-state Poor-share rank
#18 of 58
Among California counties with 5+ bridges, lower share ranks better
Condition distribution
Share of 964 NBI-tracked bridges by lowest applicable component rating.
Good 38.3% (369)
Fair 56.1% (541)
Poor 5.6% (54)
Santa Clara County's Poor-condition bridges carry 1,499,973 vehicle crossings a day
That is 4.8% of the county's reported daily bridge traffic on 5.6% of its bridges: Poor-condition structures carry less traffic than their share of the inventory. Each Poor bridge averages 27,777 crossings a day against 34,452 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 964 of 964 bridges in this county that report an average daily traffic count. Source: FHWA National Bridge Inventory, 2024 release.
56.5% of Santa Clara County's bridges have passed the 50-year mark
545 of the 964 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 38.3% 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 11% of the county's Poor-condition bridge traffic
INTERSTATE 880 over NORTH FOURTH STREET, built 1960, carries 165,000 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 54-bridge count understates how much of the daily burden sits on a single crossing.
Share is of the 1,499,973 daily crossings on Poor-rated bridges that report a traffic count. Source: FHWA National Bridge Inventory, 2024 release.
When Santa Clara County's bridges were built
964 bridges with a recorded construction year, grouped by decade
- 1900s 5
1900–1909
5 bridges
- 1910s 24
1910–1919
24 bridges
- 1920s 38
1920–1929
38 bridges
- 1930s 28
1930–1939
28 bridges
- 1940s 29
1940–1949
29 bridges
- 1950s 64
1950–1959
64 bridges
- 1960s
1960–1969
215 bridges
- 1970s
1970–1979
189 bridges
- 1980s
1980–1989
95 bridges
- 1990s
1990–1999
196 bridges
- 2000s 60
2000–2009
60 bridges
- 2010s 21
2010–2019
21 bridges
What this shows Construction peaked in the 1960s, when 215 of the county's bridges still in the inventory were built, which is 22.3% of those with a recorded year. That cohort is now 55 to 64 years old in the 2024 inventory. Its average build year (1972) matches the California average (1970).
How Santa Clara County compares with California's closest counties by inventory size
The 5 California counties nearest Santa Clara County in number of bridges, with their condition splits. Its 5.6% Poor share is the 5th-lowest of these 6. Its average build year of 1972 against a peer-group mean of 1974 is in line with the group.
Showing the 5 closest of 57 California counties eligible for comparison.
| County | Bridges | Good | Fair | Poor | Avg. built |
|---|---|---|---|---|---|
| Orange County | 1,164 | 53.2% | 43.8% | 3% | 1978 |
| Riverside County | 1,117 | 56.4% | 41.2% | 2.4% | 1977 |
| Santa Clara County (this page) | 964 | 38.3% | 56.1% | 5.6% | 1972 |
| Fresno County | 916 | 38.9% | 57.3% | 3.8% | 1969 |
| Sacramento County | 740 | 50.9% | 45.7% | 3.4% | 1973 |
| Kern County | 668 | 50.1% | 43.3% | 6.6% | 1972 |
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 Santa Clara 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 Santa Clara County, both outside California so the neighborhoods are not the same-state size table above.
Similar inventory size
Nearest county inventories outside CA (964 bridges here).
- Marion County, IN · 958 bridges
- Denton County, TX · 991 bridges
- Hennepin County, MN · 936 bridges
- Jackson County, MO · 930 bridges
Similar average build year
Nearest mean year-built outside CA (1972 here).
- Madison County, AL · avg 1972 · 710 bridges
- York County, PA · avg 1972 · 569 bridges
- Middlesex County, NJ · avg 1972 · 563 bridges
- Saunders County, NE · avg 1972 · 506 bridges
Source: FHWA National Bridge Inventory, 2024 release. Peers floor at 10 bridges so stub inventories cannot own the match.
Poor-condition bridges (54)
WALSH AVE
PoorOver: SAN TOMAS AQUINO CREEK
NEAR SAN TOMAS EXPWY, Santa Clara, CA
Built 1973 Load: 48.3 t ADT: 18,000
MTN VIEW-ALVISO RD
PoorOver: SAN TOMAS AQUINO CREEK
JUST SOUTH OF SH 237, Santa Clara, CA
Built 1973 Load: 50.5 t ADT: 5,291
YOSEMITE DRIVE
PoorOver: INTERSTATE 680
04-SCL-680-M6.98-MPS, Santa Clara, CA
Built 1974 Load: 51.2 t ADT: 11,717
S680-S101 CONNECTR
PoorOver: I 280 I 680 US 101 STORY
04-SCL-680-M0.01-SJS, Santa Clara, CA
Built 1982 Load: 57.0 t ADT: 36,000
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.