Total bridges
528
Public highway bridges in Merced County
County profile · official public datasets
Merced County, CA
528 public highway bridges tracked in the FHWA National Bridge Inventory: 32.2% rated Good, 59.5% Fair, 8.3% Poor.
- 528
- Public bridges
- 32.2%
- Good condition
- 8.3%
- Poor condition
The verdict
According to the Federal Highway Administration's 2024 National Bridge Inventory.
Merced County posts a higher-than-median Poor-condition share among rated counties in the state across large county bridge inventory.
- 39th
- of 58 on Poor share
- 8.3%
- Poor-condition share
- 528
- public highway bridges
- 1967
- 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.
Merced County Bridge Snapshot
According to the Federal Highway Administration's 2024 National Bridge Inventory, Merced County ranks #39 of 58 California counties with at least 5 public highway bridges on Poor-condition share (lower share ranks better; currently 8.3%). Merced County, California contains 528 public highway bridges. Roughly 32.2% are rated “Good,” 59.5% “Fair,” and 8.3% “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
32.2%
170 of 528 rated 7-9
Fair condition
59.5%
314 of 528 rated 5-6
Poor condition
8.3%
44 of 528 rated 4 or below
In-state Poor-share rank
#39 of 58
Among California counties with 5+ bridges, lower share ranks better
Condition distribution
Share of 528 NBI-tracked bridges by lowest applicable component rating.
Good 32.2% (170)
Fair 59.5% (314)
Poor 8.3% (44)
Merced County's Poor-condition bridges carry 296,215 vehicle crossings a day
That is 9.1% of the county's reported daily bridge traffic on 8.3% of its bridges: Poor-condition structures carry more traffic than their share of the inventory. Each Poor bridge averages 6,732 crossings a day against 7,217 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 528 of 528 bridges in this county that report an average daily traffic count. Source: FHWA National Bridge Inventory, 2024 release.
70.3% of Merced County's bridges have passed the 50-year mark
371 of the 528 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 32.2% 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 8.6% of the county's Poor-condition bridge traffic
STATE ROUTE 99 NB over BLACK RASCAL CANAL, built 1962, carries 25,500 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 44-bridge count understates how much of the daily burden sits on a single crossing.
Share is of the 296,215 daily crossings on Poor-rated bridges that report a traffic count. Source: FHWA National Bridge Inventory, 2024 release.
When Merced County's bridges were built
528 bridges with a recorded construction year, grouped by decade
- 1910s 9
1910–1919
9 bridges
- 1920s 29
1920–1929
29 bridges
- 1930s 35
1930–1939
35 bridges
- 1940s 45
1940–1949
45 bridges
- 1950s 58
1950–1959
58 bridges
- 1960s
1960–1969
156 bridges
- 1970s 56
1970–1979
56 bridges
- 1980s 38
1980–1989
38 bridges
- 1990s 24
1990–1999
24 bridges
- 2000s 37
2000–2009
37 bridges
- 2010s 37
2010–2019
37 bridges
- 2020s 4
2020–2029
4 bridges
What this shows Construction peaked in the 1960s, when 156 of the county's bridges still in the inventory were built, which is 29.5% of those with a recorded year. That cohort is now 55 to 64 years old in the 2024 inventory. Its average build year (1967) matches the California average (1970).
How Merced County compares with California's closest counties by inventory size
The 5 California counties nearest Merced County in number of bridges, with their condition splits. Its 8.3% Poor share is the 6th-lowest of these 6. Its average build year of 1967 against a peer-group mean of 1965 is in line with the group.
Showing the 5 closest of 57 California counties eligible for comparison.
| County | Bridges | Good | Fair | Poor | Avg. built |
|---|---|---|---|---|---|
| Sonoma County | 609 | 24.1% | 69% | 6.9% | 1967 |
| Tulare County | 589 | 42.4% | 54.2% | 3.4% | 1959 |
| Merced County (this page) | 528 | 32.2% | 59.5% | 8.3% | 1967 |
| Ventura County | 501 | 55.7% | 40.1% | 4.2% | 1969 |
| Shasta County | 492 | 47.6% | 49.4% | 3% | 1967 |
| Tehama County | 450 | 36.9% | 56.2% | 6.9% | 1961 |
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 Merced 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 Merced County, both outside California so the neighborhoods are not the same-state size table above.
Similar inventory size
Nearest county inventories outside CA (528 bridges here).
- LaSalle County, IL · 528 bridges
- Nueces County, TX · 528 bridges
- New Castle County, DE · 527 bridges
- Marathon County, WI · 530 bridges
Similar average build year
Nearest mean year-built outside CA (1967 here).
- Allegheny County, PA · avg 1967 · 1,294 bridges
- Suffolk County, MA · avg 1967 · 489 bridges
- Multnomah County, OR · avg 1967 · 473 bridges
- Le Flore County, OK · avg 1967 · 469 bridges
Source: FHWA National Bridge Inventory, 2024 release. Peers floor at 10 bridges so stub inventories cannot own the match.
Fair-condition bridges (314)
STATE ROUTE 99 NB
FairOver: BEAR CREEK
10-MER-099-16.38-MER, Merced, CA
Built 1962 Load: 23.7 t ADT: 25,500
STATE ROUTE 59 NB
FairOver: BEAR CREEK
10-MER-059-15.23-MER, Merced, CA
Built 1940 Load: 24.0 t ADT: 14,000
STATE ROUTE 152 WB
FairOver: DELTA-MENDOTA CANAL
10-MER-152-15.09, Merced, CA
Built 1955 Load: 24.0 t ADT: 12,425
STATE ROUTE 152 EB
FairOver: DELTA-MENDOTA CANAL
10-MER-152-15.09, Merced, CA
Built 1950 Load: 24.0 t ADT: 12,425
STATE ROUTE 99 NB
FairOver: STATE ROUTE 140
10-MER-099-15.78-MER, Merced, CA
Built 1962 Load: 24.0 t ADT: 25,500
STATE ROUTE 140
FairOver: DELTA-MENDOTA CANAL
10-MER-140-0.58, Merced, CA
Built 1951 Load: 24.0 t ADT: 1,175
BAXTER ROAD
FairOver: DUTCHMAN CREEK
1.2 MI N BUCHANAN HLW RD, Merced, CA
Built 1965 Load: 24.0 t ADT: 50
WOLFSEN ROAD
FairOver: SALT SLOUGH
0.8 MI N/E OF SR 165, Merced, CA
Built 1949 Load: 24.0 t ADT: 105
STATE ROUTE 33
FairOver: OUTSIDE CANAL
10-MER-033-18.41, Merced, CA
Built 1936 Load: 24.3 t ADT: 7,475
STATE ROUTE 140
FairOver: EL CAPITAN CANAL
10-MER-140-34.51, Merced, CA
Built 1920 Load: 24.3 t ADT: 6,500
STATE ROUTE 99 NB
FairOver: STATE ROUTE 140
10-MER-099-13.86-MER, Merced, CA
Built 1962 Load: 24.3 t ADT: 21,000
AZUSA ROAD
FairOver: SAN JUAN CANAL
0.5 MI E OF SR 33, Merced, CA
Built 1922 Load: 24.3 t ADT: 500
SNELLING ROAD
FairOver: SOUTH FORK CANAL CREEK
3.3 MI S/O SR 59, Merced, CA
Built 1966 Load: 24.3 t ADT: 1,500
HORNITOS ROAD
FairOver: F. P. CREEK
2.3 MI SE MERCED FALLS RD, Merced, CA
Built 1971 Load: 24.3 t ADT: 300
INGOMAR GRADE ROAD
FairOver: SAN LUIS WASTEWAY
0.5 MI NW HENRY MILLER AV, Merced, CA
Built 1950 Load: 24.3 t ADT: 6,331
OSLO ROAD
FairOver: LATERAL #6
0.5 MI N AUGUST AVENUE, Merced, CA
Built 1950 Load: 24.3 t ADT: 40
YAMATO WAY
FairOver: LIVINGSTON CANAL
AT EUCALYPTUS AVE, Merced, CA
Built 1960 Load: 24.3 t ADT: 40
CENTRAL AVENUE
FairOver: LIVINGSTON CANAL
AT OLIVE AVE, Merced, CA
Built 1950 Load: 24.3 t ADT: 620
FOX ROAD
FairOver: CANAL CREEK
20 FT. N BELLEVUE ROAD, Merced, CA
Built 1960 Load: 24.3 t ADT: 145
REILLY ROAD
FairOver: MILES CREEK
0.7 MI E OF SR 59, Merced, CA
Built 1955 Load: 24.3 t ADT: 150
EAST YOSEMITE AVE
FairOver: FAIRFIELD CANAL
0.9 MI W ARBOLEDA DR, Merced, CA
Built 1950 Load: 24.3 t ADT: 2,569
BUTTS ROAD
FairOver: DELTA-MENDOTA CANAL
0.7 MI W WHITWORTH ROAD, Merced, CA
Built 1950 Load: 24.3 t ADT: 10
WALTZ ROAD
FairOver: BEAR CREEK
1.2 MI NE CUNNINGHAM ROAD, Merced, CA
Built 1965 Load: 24.3 t ADT: 38
TYLER ROAD
FairOver: MILES CREEK
0.38 MI NORTH REILLY ROAD, Merced, CA
Built 1962 Load: 24.3 t ADT: 50
INDIANA AVENUE
FairOver: ARROYO CANAL
2.0 MI S OF SR 152, Merced, CA
Built 1958 Load: 24.3 t ADT: 1,095
INDIANA AVENUE
FairOver: POSO SLOUGH
2.8 MI SOUTH OF SR 152, Merced, CA
Built 1964 Load: 24.3 t ADT: 1,273
PALM AVENUE
FairOver: SAN JUAN CANAL
0.5 MI S OF SR 152, Merced, CA
Built 1959 Load: 24.3 t ADT: 1,610
DENTON ROAD
FairOver: SAN JUAN CANAL
0.1 MI W OF PALM AVE, Merced, CA
Built 1959 Load: 24.3 t ADT: 400
HEALY ROAD
FairOver: DUTCHMAN CREEK
0.1 MI N SANDY MUSH ROAD, Merced, CA
Built 1972 Load: 24.3 t ADT: 400
SANDY MUSH ROAD
FairOver: DUTCHMAN CREEK
4.2 MI W OF SR 99, Merced, CA
Built 1972 Load: 24.3 t ADT: 400
KAHLON ROAD
FairOver: MARIPOSA CREEK
2.4 MI SE OF E MISSION RD, Merced, CA
Built 1938 Load: 24.3 t ADT: 384
OLD STATE ROUTE 99
FairOver: FARMDALE SLOUGH
0.2 MI SE/O E MISSION AV, Merced, CA
Built 1938 Load: 24.3 t ADT: 270
OLD STATE ROUTE 99
FairOver: NORTH FARMDALE SLOUGH
0.2 MI NW/O E MISSION AV, Merced, CA
Built 1938 Load: 24.3 t ADT: 270
STATE ROUTE 152
FairOver: CCID MAIN CANAL
10-MER-152-19.52-LBNS, Merced, CA
Built 1923 Load: 24.6 t ADT: 28,000
STATE ROUTE 99 SB
FairOver: STATE ROUTE 140
10-MER-099-13.86-MER, Merced, CA
Built 1962 Load: 24.6 t ADT: 21,000
INTERSTATE 5 SB
FairOver: SAN LUIS WASTEWAY
10-MER-005-21.42, Merced, CA
Built 1966 Load: 24.6 t ADT: 15,500
INTERSTATE 5 NB
FairOver: SAN LUIS WASTEWAY
10-MER-005-21.42, Merced, CA
Built 1966 Load: 24.6 t ADT: 17,300
WHEALAN ROAD
FairOver: MILES CREEK
0.3 MI N MISSION AVE, Merced, CA
Built 1968 Load: 24.6 t ADT: 218
STATE ROUTE 99 NB
FairOver: R STREET
10-MER-099-15.42-MER, Merced, CA
Built 1962 Load: 24.9 t ADT: 25,500
OAKDALE ROAD
FairOver: CANAL CREEK
0.9 MI E AMSTERDAM RD, Merced, CA
Built 1940 Load: 24.9 t ADT: 477
OLIVE AVE
FairOver: FAIRFIELD CANAL
1.0 MI W ARBOLEDA DR, Merced, CA
Built 1974 Load: 24.9 t ADT: 1,945
COTTONWOOD ROAD
FairOver: CCID MAIN CANAL
0.5 MI E OF SR 33, Merced, CA
Built 1926 Load: 24.9 t ADT: 340
CUNNINGHAM RD
FairOver: MILES CREEK
2.2 MI N CHILDS AVE, Merced, CA
Built 1983 Load: 24.9 t ADT: 34
STATE ROUTE 33
FairOver: POSO SLOUGH
10-MER-033-4.37, Merced, CA
Built 1962 Load: 25.6 t ADT: 5,200
MINTURN ROAD
FairOver: N BRANCH DEADMAN CREEK
0.8 MI N BUCHAN HOLLOW RD, Merced, CA
Built 1974 Load: 25.6 t ADT: 1,540
OLIVE AVE
FairOver: WASTEWAY
0.9 MI W ARBOLEDA DR, Merced, CA
Built 1960 Load: 25.6 t ADT: 1,945
COTTONWOOD RD
FairOver: INTERSTATE 5
10-MER-005-28.23, Merced, CA
Built 1967 Load: 25.9 t ADT: 25
STATE ROUTE 59
FairOver: OWENS CREEK
10-MER-059-11.37, Merced, CA
Built 1925 Load: 26.2 t ADT: 7,700
TAGLIO ROAD
FairOver: DELTA-MENDOTA CANAL
0.1 MI W ORCHARD ROAD, Merced, CA
Built 1956 Load: 26.2 t ADT: 150
STATE ROUTE 140
FairOver: OUTSIDE CANAL
10-MER-140-2.30, Merced, CA
Built 1968 Load: 26.6 t ADT: 1,175
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.