Total bridges
818
Public highway bridges in Middlesex County
County profile · official public datasets
Middlesex County, MA
818 public highway bridges tracked in the FHWA National Bridge Inventory: 20.7% rated Good, 68.2% Fair, 11.1% Poor.
- 818
- Public bridges
- 20.7%
- Good condition
- 11.1%
- Poor condition
The verdict
According to the Federal Highway Administration's 2024 National Bridge Inventory.
Middlesex County posts a higher-than-median Poor-condition share among rated counties in the state across large county bridge inventory.
- 11th
- of 13 on Poor share
- 11.1%
- Poor-condition share
- 818
- public highway bridges
- 1958
- 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.
Middlesex County Bridge Snapshot
According to the Federal Highway Administration's 2024 National Bridge Inventory, Middlesex County ranks #11 of 13 Massachusetts counties with at least 5 public highway bridges on Poor-condition share (lower share ranks better; currently 11.1%). Middlesex County, Massachusetts contains 818 public highway bridges. Roughly 20.7% are rated “Good,” 68.2% “Fair,” and 11.1% “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
20.7%
169 of 818 rated 7-9
Fair condition
68.2%
558 of 818 rated 5-6
Poor condition
11.1%
91 of 818 rated 4 or below
In-state Poor-share rank
#11 of 13
Among Massachusetts counties with 5+ bridges, lower share ranks better
Condition distribution
Share of 818 NBI-tracked bridges by lowest applicable component rating.
Good 20.7% (169)
Fair 68.2% (558)
Poor 11.1% (91)
Middlesex County's Poor-condition bridges carry 3,395,813 vehicle crossings a day
That is 12.7% of the county's reported daily bridge traffic on 11.1% of its bridges: Poor-condition structures carry more traffic than their share of the inventory. Each Poor bridge averages 37,317 crossings a day against 21,585 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 818 of 818 bridges in this county that report an average daily traffic count. Source: FHWA National Bridge Inventory, 2024 release.
70.5% of Middlesex County's bridges have passed the 50-year mark
577 of the 818 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 20.7% 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 5.9% of the county's Poor-condition bridge traffic
I 93 over I 95 /ST128, built 1957, carries 200,824 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 91-bridge count understates how much of the daily burden sits on a single crossing.
Share is of the 3,395,813 daily crossings on Poor-rated bridges that report a traffic count. Source: FHWA National Bridge Inventory, 2024 release.
When Middlesex County's bridges were built
818 bridges with a recorded construction year, grouped by decade
- pre-1900 68
Built before 1900
68 bridges
- 1900s 45
1900–1909
45 bridges
- 1910s 21
1910–1919
21 bridges
- 1920s 23
1920–1929
23 bridges
- 1930s 39
1930–1939
39 bridges
- 1940s 25
1940–1949
25 bridges
- 1950s
1950–1959
179 bridges
- 1960s
1960–1969
161 bridges
- 1970s 33
1970–1979
33 bridges
- 1980s 29
1980–1989
29 bridges
- 1990s 45
1990–1999
45 bridges
- 2000s
2000–2009
90 bridges
- 2010s 44
2010–2019
44 bridges
- 2020s 16
2020–2029
16 bridges
What this shows Construction peaked in the 1950s, when 179 of the county's bridges still in the inventory were built, which is 21.9% of those with a recorded year. That cohort is now 65 to 74 years old in the 2024 inventory. Its average build year (1958) matches the Massachusetts average (1961).
How Middlesex County compares with Massachusetts's closest counties by inventory size
The 5 Massachusetts counties nearest Middlesex County in number of bridges, with their condition splits. Its 11.1% Poor share is the 5th-lowest of these 6. Its average build year of 1958 against a peer-group mean of 1961 is in line with the group.
Showing the 5 closest of 12 Massachusetts counties eligible for comparison.
| County | Bridges | Good | Fair | Poor | Avg. built |
|---|---|---|---|---|---|
| Worcester County | 1,014 | 25.5% | 66.9% | 7.6% | 1963 |
| Middlesex County (this page) | 818 | 20.7% | 68.2% | 11.1% | 1958 |
| Suffolk County | 489 | 22.7% | 67.7% | 9.6% | 1967 |
| Berkshire County | 450 | 34.7% | 57.6% | 7.8% | 1961 |
| Hampden County | 428 | 17.1% | 75.5% | 7.5% | 1956 |
| Essex County | 395 | 15.9% | 66.8% | 17.2% | 1957 |
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.
Nationwide counties with similar inventory size or average build year
Two NBI-derived peer sets for Middlesex County, both outside Massachusetts so the neighborhoods are not the same-state size table above.
Similar inventory size
Nearest county inventories outside MA (818 bridges here).
- Montgomery County, PA · 828 bridges
- Duval County, FL · 831 bridges
- Davidson County, TN · 832 bridges
- Lancaster County, PA · 801 bridges
Similar average build year
Nearest mean year-built outside MA (1958 here).
- Bucks County, PA · avg 1958 · 699 bridges
- Butte County, CA · avg 1958 · 437 bridges
- Cowley County, KS · avg 1958 · 337 bridges
- Marin County, CA · avg 1958 · 207 bridges
Source: FHWA National Bridge Inventory, 2024 release. Peers floor at 10 bridges so stub inventories cannot own the match.
Good-condition bridges (169)
HWY TAYLOR ST
GoodOver: I 495
0.25 MI S. ST. RTE 2, Middlesex, MA
Built 2015 Load: 1.1 t ADT: 3,000
HWY MAIN ST
GoodOver: WATER SUDBURY RIVER
.1 MI S OF ST-9, Middlesex, MA
Built 1878 Load: 20.2 t ADT: 7,950
HWY MYST VAL PKY
GoodOver: WATER ABERJONA RIVER
ADJACENT TO BMRR, Middlesex, MA
Built 1896 Load: 20.3 t ADT: 6,206
HWY TOWN FARM LN
GoodOver: RR MBTA/BMRR
1 MI S RT 3A & WOBURN ST, Middlesex, MA
Built 1925 Load: 22.7 t ADT: 800
HWY FRANKLIN ST
GoodOver: WATER SUDBURY RIVER
1000 FT N MT WAITE AV, Middlesex, MA
Built 1934 Load: 26.8 t ADT: 4,387
HWY BENNETTS CRS
GoodOver: WATER BENNETTS BROOK
150 SOUTH OF ROUTE 2A, Middlesex, MA
Built 1991 Load: 32.4 t ADT: 200
HWY PINGRY WAY
GoodOver: WATER BENNETTS BRK TRIB
850 FEET E OF BENNETTS CR, Middlesex, MA
Built 1991 Load: 32.4 t ADT: 200
HWY MIDDLESEX TP
GoodOver: WATER VINE BROOK
150 S OF ST-62, Middlesex, MA
Built 1998 Load: 32.4 t ADT: 6,207
ST129 BILLERICA RD
GoodOver: WATER RIVER MEADOW BROOK
1.6 KM W OF RTE 3, Middlesex, MA
Built 2022 Load: 32.4 t ADT: 14,535
HWY SHORE DRIVE
GoodOver: WATER FREEMAN LAKE SPLWY
0.3 MI WEST OF GRACE ST, Middlesex, MA
Built 1975 Load: 32.4 t ADT: 300
HWY CAMBRDGE TPK
GoodOver: WATER MILL BROOK
0.8 MI NW OF ST-2, Middlesex, MA
Built 2020 Load: 32.4 t ADT: 3,900
ST 9 WORCESTER RD
GoodOver: WATER RESERVOIR OUTLET
.5 MI. WEST OF TEMPLE ST, Middlesex, MA
Built 2016 Load: 32.4 t ADT: 41,604
I 90 EB
GoodOver: WATER MDC RES 3
MM 112/E OF EXIT 111/ST9, Middlesex, MA
Built 1957 Load: 32.4 t ADT: 52,197
HWY HILLSIDE DR
GoodOver: WATER DEER BROOK
0.2 MI S OF MARSHALL ST, Middlesex, MA
Built 2000 Load: 32.4 t ADT: 400
HWY OLD SWMLL RD
GoodOver: WATER DEER BROOK
RE, Middlesex, MA
Built 2000 Load: 32.4 t ADT: 400
HWY FRUIT ST
GoodOver: COMB MBTA/CSX & SUDBURY
.7 MI EAST OF I - 495, Middlesex, MA
Built 2023 Load: 32.4 t ADT: 2,600
HWY WEDGEWOOD DR
GoodOver: WATER BROOK
150 FT W OF SINGLETARY WY, Middlesex, MA
Built 2000 Load: 32.4 t ADT: 1,800
HWY CENTRAL ST
GoodOver: WATER LWR PAWTUCKET CNL
SOUTH OF MARKET ST, Middlesex, MA
Built 1835 Load: 32.4 t ADT: 12,184
HWY MARKET ST
GoodOver: WATER WESTERN CANAL
AT MICHALOPOULOS SQ, Middlesex, MA
Built 2019 Load: 32.4 t ADT: 6,900
HWY PAWTUCKET ST
GoodOver: WATER NORTHERN CANAL
AT FRENCH ST EXT, Middlesex, MA
Built 2022 Load: 32.4 t ADT: 2,900
HWY PAWTUCKET ST
GoodOver: WATER PAWTUCKET CANAL
AT MERRIMACK RIVER, Middlesex, MA
Built 2021 Load: 32.4 t ADT: 18,800
HWY VFW HWY
GoodOver: WATER BEAVER BROOK
1.6 KM E UNVRSTY OF LWLL, Middlesex, MA
Built 2022 Load: 32.4 t ADT: 25,788
HWY CANAL ST
GoodOver: WATER PAWTUCKET CANAL
0.15 KM FROM DUTTON ST, Middlesex, MA
Built 2019 Load: 32.4 t ADT: 10
HWY ELM ST
GoodOver: WATER MILLHAM BROOK
960 E OF BOUNDARY ST, Middlesex, MA
Built 2015 Load: 32.4 t ADT: 1,164
HWY FLORIDA RD
GoodOver: WATER ASSABET RIVER
0.1 MI N OF ST-62, Middlesex, MA
Built 2023 Load: 32.4 t ADT: 2,850
ST 38 MAIN ST
GoodOver: WATER MYSTIC RIVER
.1 MI N OF ST16, Middlesex, MA
Built 1908 Load: 32.4 t ADT: 67,900
HWY LONGLEY RD
GoodOver: WATER MULPUS BROOK
.1 MI. NE. OF RT. 2A, Middlesex, MA
Built 2021 Load: 32.4 t ADT: 800
HWY BROADWAY
GoodOver: RR MBTA/BMRR
2.4 KM NW OF JCT SR28&38, Middlesex, MA
Built 2020 Load: 32.4 t ADT: 28,000
HWY DUTTON RD
GoodOver: WATER HOP BROOK
0.4 MI SOUTH OF HUDSON RD, Middlesex, MA
Built 2021 Load: 32.4 t ADT: 4,000
HWY W MEADOW RD
GoodOver: WATER LOCKE BROOK
.15 MI. N. OF ST-119, Middlesex, MA
Built 2021 Load: 32.4 t ADT: 516
HWY WOERD AVE
GoodOver: WATER CHARLES RIVER
.6 KM. NE. OF NEWTON LINE, Middlesex, MA
Built 2021 Load: 32.4 t ADT: 2,760
HWY BEAVER BK RD
GoodOver: WATER BEAVER BROOK
.2 MI. E. OF LITTLETON LN, Middlesex, MA
Built 2023 Load: 32.4 t ADT: 2,929
ST 62 MIDDLESEX AV
GoodOver: WATER LUBBERS BROOK
225FT W OF NORTH STREET, Middlesex, MA
Built 2022 Load: 32.4 t ADT: 26,800
HWY SWANTON ST
GoodOver: WATER ABERJONA RIVER
E OF RT38 N OF WNCHSTR CT, Middlesex, MA
Built 2021 Load: 32.4 t ADT: 10,344
HWY SALEM ST
GoodOver: RR MBTA/BMRR
1.9 KM S RTE 93, Middlesex, MA
Built 2021 Load: 32.4 t ADT: 25,000
US 20 WB/BSTN PST
GoodOver: I 495
1.8 MI. E. OF NTHBORO TL., Middlesex, MA
Built 1962 Load: 32.5 t ADT: 28,074
HWY RINDGE RD
GoodOver: WATER FALULAH BROOK
3.6 MI. W. OF ST. 31, Middlesex, MA
Built 1997 Load: 32.7 t ADT: 3,103
HWY JEFFERSON ST
GoodOver: WATER WESTERN CANAL
0.96 KM. SW. OF RT. 38, Middlesex, MA
Built 1850 Load: 33.3 t ADT: 650
HWY WHITE PND RD
GoodOver: WATER ASSABET RIVER
.5 MI. S. OF ST.117, Middlesex, MA
Built 2007 Load: 33.5 t ADT: 180
HWY RIVER ST
GoodOver: WATER STONY BROOK
.1 MI SE OF NORTH ST, Middlesex, MA
Built 1997 Load: 33.5 t ADT: 3,100
HWY LINCOLN ST
GoodOver: COMB CSX & QUEBEC ST
0.40 KM W RT 3A, Middlesex, MA
Built 2002 Load: 33.9 t ADT: 1,681
HWY PEABODY ST
GoodOver: OTHER DEM RAIL TRAIL
0.4 MI SO OF RTE 111, Middlesex, MA
Built 2002 Load: 35.0 t ADT: 714
HWY GRAY ST
GoodOver: RR MBTA/BMRR
.4 MILES TWKS. TWN. LINE, Middlesex, MA
Built 1996 Load: 35.5 t ADT: 4,300
I 90 WB
GoodOver: WATER MDC RES 3
0.7 MI E OF TEMPLE ST, Middlesex, MA
Built 1957 Load: 35.6 t ADT: 47,529
HWY BROADWAY
GoodOver: WATER PAWTUCKET CANAL
NEAR GATE HOUSE, Middlesex, MA
Built 1852 Load: 35.6 t ADT: 9,000
ST 16 REV BCH PKWY
GoodOver: COMB RIVERS EDGE&MBTA&O
.2 MI E OF FELLSWAY, Middlesex, MA
Built 2018 Load: 35.6 t ADT: 68,300
HWY SPEEN ST
GoodOver: WATER FISKE POND
@ ST.135 AND SPEEN ST, Middlesex, MA
Built 2011 Load: 35.6 t ADT: 14,500
HWY TURNPIKE RD
GoodOver: WATER SQUANNACOOK RIVER
AT BARKER HILL ROAD, Middlesex, MA
Built 1999 Load: 35.6 t ADT: 1,699
HWY PELHAM IS RD
GoodOver: WATER SUDBURY RIVER
.4MI SW OF RT. 20, Middlesex, MA
Built 2012 Load: 35.6 t ADT: 1,900
I 90 RAMP R
GoodOver: OTHER MWRA AQUEDUCT
I-90 WB EXIT 15A RAMP, Middlesex, MA
Built 2017 Load: 35.6 t ADT: 7,800
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.