Total bridges
563
Public highway bridges in Middlesex County
County profile · official public datasets
563 public highway bridges tracked in the FHWA National Bridge Inventory: 23.4% rated Good, 72.1% Fair, 4.4% Poor.
The verdict
According to the Federal Highway Administration's 2024 National Bridge Inventory.
Middlesex County pairs a better-than-median Poor-condition share among rated counties in the state with a newer average build year than the state inventory.
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.
According to the Federal Highway Administration's 2024 National Bridge Inventory, Middlesex County ranks #7 of 21 New Jersey counties with at least 5 public highway bridges on Poor-condition share (lower share ranks better; currently 4.4%). Middlesex County, New Jersey contains 563 public highway bridges. Roughly 23.4% are rated “Good,” 72.1% “Fair,” and 4.4% “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.
Total bridges
563
Public highway bridges in Middlesex County
Good condition
23.4%
132 of 563 rated 7-9
Fair condition
72.1%
406 of 563 rated 5-6
Poor condition
4.4%
25 of 563 rated 4 or below
In-state Poor-share rank
#7 of 21
Among New Jersey counties with 5+ bridges, lower share ranks better
Share of 563 NBI-tracked bridges by lowest applicable component rating.
That is 2.1% of the county's reported daily bridge traffic on 4.4% of its bridges: Poor-condition structures carry less traffic than their share of the inventory. Each Poor bridge averages 16,106 crossings a day against 29,014 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 563 of 563 bridges in this county that report an average daily traffic count. Source: FHWA National Bridge Inventory, 2024 release.
330 of the 563 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 23.4% 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.
US 1 over FORRESTAL ROAD, built 1932, carries 67,565 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 25-bridge count understates how much of the daily burden sits on a single crossing.
Share is of the 402,662 daily crossings on Poor-rated bridges that report a traffic count. Source: FHWA National Bridge Inventory, 2024 release.
563 bridges with a recorded construction year, grouped by decade
Built before 1900
4 bridges
1900–1909
3 bridges
1910–1919
6 bridges
1920–1929
21 bridges
1930–1939
26 bridges
1940–1949
28 bridges
1950–1959
67 bridges
1960–1969
65 bridges
1970–1979
125 bridges
1980–1989
44 bridges
1990–1999
92 bridges
2000–2009
48 bridges
2010–2019
34 bridges
What this shows Construction peaked in the 1970s, when 125 of the county's bridges still in the inventory were built, which is 22.2% of those with a recorded year. That cohort is now 45 to 54 years old in the 2024 inventory. Its average build year is 1972, 6 years newer than the New Jersey average of 1966.
The 5 New Jersey counties nearest Middlesex County in number of bridges, with their condition splits. Its 4.4% Poor share is the 2nd-lowest of these 6. Its average build year of 1972 against a peer-group mean of 1967 is 5 years newer.
Showing the 5 closest of 20 New Jersey counties eligible for comparison.
| County | Bridges | Good | Fair | Poor | Avg. built |
|---|---|---|---|---|---|
| Bergen County | 577 | 19.1% | 76.1% | 4.9% | 1964 |
| Middlesex County (this page) | 563 | 23.4% | 72.1% | 4.4% | 1972 |
| Morris County | 508 | 19.7% | 74.4% | 5.9% | 1964 |
| Essex County | 505 | 16.2% | 81% | 2.8% | 1963 |
| Monmouth County | 505 | 32.9% | 58.2% | 8.9% | 1971 |
| Mercer County | 414 | 40.3% | 50.5% | 9.2% | 1975 |
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 Middlesex County's. Source: FHWA National Bridge Inventory, 2024 release.
Two NBI-derived peer sets for Middlesex County, both outside New Jersey so the neighborhoods are not the same-state size table above.
Nearest county inventories outside NJ (563 bridges here).
Nearest mean year-built outside NJ (1972 here).
Source: FHWA National Bridge Inventory, 2024 release. Peers floor at 10 bridges so stub inventories cannot own the match.
Over: PORT READING RR & 94UTRN
0.9 MI N WOODBRIDGE SA, Middlesex, NJ
Over: BOUND BROOK
1.47M E.of CR622, Middlesex, NJ
Over: RAMPG(18SBTOCR672)
2.7 MILES NORTH OF US 1, Middlesex, NJ
Over: SAWMILL BROOK
1.4 MI SOUTH OF INT 9, Middlesex, NJ
Over: NJ TPK SNO RWY
AT INT 8A, Middlesex, NJ
Over: NJ Transit and Inman Ave
1 MI S OF RAHWAY RIVER, Middlesex, NJ
Over: US 9 NB AND RAMP 8
RT 18 & US 9 INTERCHANGE, Middlesex, NJ
Over: NJ 440 NB RAMP
0.6MI WEST OF GSP, Middlesex, NJ
Over: MILLSTONE RIVER
0.7 MILE NORTH OF RTE 33, Middlesex, NJ
Over: NJ TPK NSO-NSI SNI SNO
2.8 MI SOUTH OF INT 9, Middlesex, NJ
Over: CONRAIL JAMESBURG BR
.4 MI N INTERCHANGE 8A, Middlesex, NJ
Over: RARITAN RIVER
0.06 M North of CR 672, Middlesex, NJ
Over: SAWMILL BROOK
1.4 MI SOUTH OF INT 9, Middlesex, NJ
Over: MILL BROOK
0.62 miles E. of Mill Rd, Middlesex, NJ
Over: NJ 440
0.27 MI EAST OF ROUTE 35, Middlesex, NJ
Over: US ROUTE 1
1.35 MI SOUTH OF NJ 27, Middlesex, NJ
Over: NJ 18
3.01 Mi W. of US-9, Middlesex, NJ
Over: MANALAPAN BROOK
FORSGATE & RR AVE JCT, Middlesex, NJ
Over: I-287
0.53 MI S of I-287 Exit 6, Middlesex, NJ
Over: NJ TPK(I-95) NSO RWY
0.20 MI SW OF I-95, Middlesex, NJ
Over: NEW MARKET POND&CONRAIL
0.31 miles south of CR601, Middlesex, NJ
Over: NJ TPK(I-95) SNO RWY
0.60 MI SW OF I-95, Middlesex, NJ
Over: GREEN BROOK
0.5 MILE NORTH OF NJ 28, Middlesex, NJ
Over: PORT READING SECONDARY
0.31 MILE NE OF GROVE ST, Middlesex, NJ
Over: TRIB S. BR. RAHWAY RIVER
0.2 MI S. OF PARSONAGE RD, Middlesex, NJ
Over: RARITAN R JOHNSON GEORGE
1.13MI W OF NJ18&27 JCT, Middlesex, NJ
Over: AMTRAK
0.2 MI W/SCHALKS STN ROAD, Middlesex, NJ
Over: MATCHAPONIX BROOK
0.71 MI S OF PENSION ROAD, Middlesex, NJ
Over: US 1
1.35 MILES NORTH OF RT.18, Middlesex, NJ
Over: US 9
0.74 N. OF JCT 9 AND 34., Middlesex, NJ
Over: US 9 SB
AT 18-9 INTERCHANGE, Middlesex, NJ
Over: US 9 SOUTHBOUND
1.13 MI N OF RT 9/520 JCT, Middlesex, NJ
Over: BURTS CREEK
1.44 miles west of CR 535, Middlesex, NJ
Over: NJ TPK NSO-NSI-SNI-SNO*
3.5 MI NORTH OF INT 8A, Middlesex, NJ
Over: SOUTH RIVER
0.06 miles north of CR677, Middlesex, NJ
Over: NJ TPK INT.9 RAMP TW
.05 MI N INTERCHANGE 9, Middlesex, NJ
Over: READING ROAD
2.5 MI NORTH OF US 1 JCT., Middlesex, NJ
Over: IRELANDS BROOK
0.8 MILE WEST OF NJTPK, Middlesex, NJ
Over: DEEP RUN
0.57 miles north of CR677, Middlesex, NJ
Over: LAWRENCE BROOK
0.3 MILE EAST OF US 130, Middlesex, NJ
Over: WOODBRIDGE CTR DR.
0.5 MI WEST OF US 9 JCT, Middlesex, NJ
Over: CRANBURY BROOK
0.3 MI S OF PLAINSBORO RD, Middlesex, NJ
Over: S BRANCH OF RAHWAY RIVER
JCT OF RMPS & STREAM, Middlesex, NJ
Over: WESTONS MILL POND
0.30 MI S OF US 1, Middlesex, NJ
Over: Voorhees St
NJ 172 & NJ 18 JCT., Middlesex, NJ
Over: LEFFERTS LAKE
0.33 miles west of CR 645, Middlesex, NJ
Over: OAKLEYS BROOK
0.2 MILE EAST OF US 130, Middlesex, NJ
Over: MILLSTONE RIVER
0.1 MI W OF Groversmill, Middlesex, NJ
Over: HEATHCOTE BROOK
0.90 MI. E. OF RT 1, Middlesex, NJ
Over: TRIBUTARY OF LAWRENCE BR
.25 mi south of Major Rd, Middlesex, NJ
Read our methodology - how this data is sourced, computed, and verified.
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.