County profile · official public datasets

Montgomery County, MD

515 public highway bridges tracked in the FHWA National Bridge Inventory: 38.8% rated Good, 56.3% Fair, 4.9% Poor.

515
Public bridges
38.8%
Good condition
4.9%
Poor condition

The verdict

According to the Federal Highway Administration's 2024 National Bridge Inventory.

Montgomery County pairs a higher-than-median Poor-condition share among rated counties in the state with a newer average build year than the state inventory.

14th
of 24 on Poor share
4.9%
Poor-condition share
515
public highway bridges
1978
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.

Montgomery County Bridge Snapshot

According to the Federal Highway Administration's 2024 National Bridge Inventory, Montgomery County ranks #14 of 24 Maryland counties with at least 5 public highway bridges on Poor-condition share (lower share ranks better; currently 4.9%). Montgomery County, Maryland contains 515 public highway bridges. Roughly 38.8% are rated “Good,” 56.3% “Fair,” and 4.9% “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

515

Public highway bridges in Montgomery County

Good condition

38.8%

200 of 515 rated 7-9

Fair condition

56.3%

290 of 515 rated 5-6

Poor condition

4.9%

25 of 515 rated 4 or below

In-state Poor-share rank

#14 of 24

Among Maryland counties with 5+ bridges, lower share ranks better

Condition distribution

Share of 515 NBI-tracked bridges by lowest applicable component rating.

Good
38.8% (200)
Fair
56.3% (290)
Poor
4.9% (25)

Montgomery County's Poor-condition bridges carry 242,194 vehicle crossings a day

That is 1.7% of the county's reported daily bridge traffic on 4.9% of its bridges: Poor-condition structures carry less traffic than their share of the inventory. Each Poor bridge averages 9,688 crossings a day against 21,166 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 513 of 515 bridges in this county that report an average daily traffic count. Source: FHWA National Bridge Inventory, 2024 release.

44.9% of Montgomery County's bridges have passed the 50-year mark

231 of the 515 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 38.8% 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 16.5% of the county's Poor-condition bridge traffic

CLARA BARTON PARKW over CLARA BARTON PARKWAY (SB, built 1959, carries 40,057 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 242,194 daily crossings on Poor-rated bridges that report a traffic count. Source: FHWA National Bridge Inventory, 2024 release.

When Montgomery County's bridges were built

515 bridges with a recorded construction year, grouped by decade

bridges

What this shows Construction peaked in the 1960s, when 84 of the county's bridges still in the inventory were built, which is 16.3% of those with a recorded year. That cohort is now 55 to 64 years old in the 2024 inventory. Its average build year is 1978, 6 years newer than the Maryland average of 1972.

Source FHWA National Bridge Inventory (year built) As of 2024 NBI release

How Montgomery County compares with Maryland's closest counties by inventory size

The 5 Maryland counties nearest Montgomery County in number of bridges, with their condition splits. Its 4.9% Poor share is the 4th-lowest of these 6. Its average build year of 1978 against a peer-group mean of 1974 is in line with the group.

Showing the 5 closest of 23 Maryland counties eligible for comparison.

Bridge inventory size and condition shares for Montgomery County and the 5 Maryland counties closest to it in inventory size
County Bridges Poor
Prince George's County 576 3.1%
Montgomery County (this page) 515 4.9%
Frederick County 486 2.7%
Anne Arundel County 389 1.5%
Baltimore city County 374 8.6%
Howard County 309 5.8%

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 Montgomery 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 Montgomery County, both outside Maryland so the neighborhoods are not the same-state size table above.

Similar inventory size

Nearest county inventories outside MD (515 bridges here).

Similar average build year

Nearest mean year-built outside MD (1978 here).

Source: FHWA National Bridge Inventory, 2024 release. Peers floor at 10 bridges so stub inventories cannot own the match.

All 515 Good 200 Fair 290 Poor 25

Good-condition bridges (200)

VALLEY ROAD

Good

Over: BOOZE CREEK

40 FT E OF FALLEN OAK RD, Montgomery, MD

Built 1964 Load: 67.4 t ADT: 216

GOLD MINE ROAD

Good

Over: HAWLINGS RIVER

0.4 MILES WEST OF MD 650, Montgomery, MD

Built 2019 Load: 67.7 t ADT: 2,792

MUNCASTER ROAD

Good

Over: ROCK CREEK

1 MILE NORTH OF MD 115, Montgomery, MD

Built 2006 Load: 68.0 t ADT: 7,803

MONTROSE ROAD

Good

Over: RAMP TO I-270

0.1 MI W OF I-270, Montgomery, MD

Built 1990 Load: 68.5 t ADT: 22,375

SUNDOWN ROAD

Good

Over: HAWLINGS RIVER

2.0 MILES EAST OF MD 108, Montgomery, MD

Built 1996 Load: 70.3 t ADT: 6,900

CLARKSBURG ROAD

Good

Over: BENNETT CREEK TRIBUTARY

0.2 MI W BETHESDA CH RD, Montgomery, MD

Built 2003 Load: 71.2 t ADT: 4,123

OLDE MILL RUN ROAD

Good

Over: MD200 (ICC)

0.7 mi E OF REDLAND RD, Montgomery, MD

Built 2010 Load: 72.1 t ADT: 1,073

ESWORTHY ROAD

Good

Over: MUDDY BRANCH

AT QUERY MILL ROAD, Montgomery, MD

Built 1999 Load: 73.0 t ADT: 3,639

BEACH DRIVE

Good

Over: SILVER CREEK

0.4 MILES EAST OF MD 185, Montgomery, MD

Built 2022 Load: 73.2 t ADT: 4,900

MD 355

Good

Over: RELOCATED RANDOLPH ROAD

2.5 MI N. OF I-495, Montgomery, MD

Built 2009 Load: 74.5 t ADT: 60,000

MD 118

Good

Over: CSX TRANSPORTATION

0.98 MILE N OF MD 117, Montgomery, MD

Built 1998 Load: 74.8 t ADT: 25,451

AVERY ROAD

Good

Over: ROCK CREEK

0.75 MI N OF JCT SR 28, Montgomery, MD

Built 1994 Load: 74.8 t ADT: 3,894

NORBECK RD & NORWO

Good

Over: NORTHWEST BRANCH

0.7 MILES EAST OF MD 182, Montgomery, MD

Built 2002 Load: 75.7 t ADT: 20,520

FATHER HURLEY BOUL

Good

Over: CSXT RAILROAD

NORTH OF MD 118, Montgomery, MD

Built 2010 Load: 76.2 t ADT: 588

GOSHEN ROAD

Good

Over: CABIN BRANCH

0.2 MI N OF CENTERWAY RD, Montgomery, MD

Built 2004 Load: 76.6 t ADT: 25,587

PYRITE LANE

Good

Over: JAMES CREEK

1.4 MILES EAST OF MD-97, Montgomery, MD

Built 2005 Load: 79.4 t ADT: 518

DORSET AVENUE

Good

Over: WILLETT BRANCH

1 MI N OF MD RTE 190, Montgomery, MD

Built 1999 Load: 80.7 t ADT: 1,744

MONTROSE ROAD

Good

Over: OLD FARM CREEK

0.5 MI. W. OF JEFFERSON, Montgomery, MD

Built 2008 Load: 85.7 t ADT: 66,690

STONEYBROOK DRIVE

Good

Over: CSXT RAILROAD

0.1 MILE WEST OF MD 192, Montgomery, MD

Built 2001 Load: 89.8 t ADT: 6,654

TIVOLI LAKE BOULEV

Good

Over: BEL PRE CREEK

1.7 MILE EAST OF MD 97, Montgomery, MD

Built 2017 Load: 96.9 t ADT: 310

CENTURY BOULEVARD

Good

Over: TRIB TO LITTLE SENECA CR

0.3 MILES WEST OF I-270, Montgomery, MD

Built 2014 Load: 96.9 t ADT: 3,720

MD 28

Good

Over: MUDDY BRANCH

0.03 MILE EAST OF MD 899A, Montgomery, MD

Built 2004 Load: 99.9 t ADT: 24,594

MD 108

Good

Over: TRIB TO JAMES CREEK

1.24 MILES EAST OF MD 97, Montgomery, MD

Built 1994 Load: 99.9 t ADT: 22,100

MD 124

Good

Over: WHETSTONE RUN

1.23 MILE NORTH OF MD 355, Montgomery, MD

Built 1990 Load: 99.9 t ADT: 23,940

IS 270 RAMP L(1)

Good

Over: GUNNERS BRANCH

IS 270/MIDDLEBROOK INTER, Montgomery, MD

Built 1991 Load: 99.9 t ADT: 6,945

CO 141 (MIDDLEBROO

Good

Over: GUNNERS BRANCH

0.1 MILE WEST OF IS 270, Montgomery, MD

Built 1959 Load: 99.9 t ADT: 16,296

LONGDRAFT ROAD

Good

Over: LONG DRAUGHT BRANCH

0.4 MI N OF GREAT SENECA, Montgomery, MD

Built 1977 Load: 99.9 t ADT: 3,200

REDLAND ROAD

Good

Over: CRABBS CREEK

0.7 MILES EAST OF MD 355, Montgomery, MD

Built 1981 Load: 99.9 t ADT: 25,649

MONTGOMERY VILLAGE

Good

Over: NORTH CREEK

2.8 MI NORTH OF MD 355, Montgomery, MD

Built 1972 Load: 99.9 t ADT: 31,432

SAM EIG HIGHWAY

Good

Over: TRIBUTARY TO MUDDY BRANC

1 MI E OF MUDDY BRANCH RD, Montgomery, MD

Built 1991 Load: 99.9 t ADT: 34,100

RANWORTH DRIVE

Good

Over: TRIBUTARY TO LITTLE SENE

0.5 MI N OF MD RTE 117, Montgomery, MD

Built 1994 Load: 99.9 t ADT: 150

WICKHAM ROAD

Good

Over: ROCK CRK NORTH BRANCH TR

N OF BOWIE MILL ROAD, Montgomery, MD

Built 2002 Load: 99.9 t ADT: 684

WICKHAM ROAD

Good

Over: TRIB. TO ROCK CREEK N. B

N OF BOWIE MILL ROAD, Montgomery, MD

Built 2002 Load: 99.9 t ADT: 376

OLD BALTIMORE ROAD

Good

Over: JAMES CREEK

1.2 MI. N. OF MD 108, Montgomery, MD

Built 1998 Load: 99.9 t ADT: 3,623

FDA BOULEVARD

Good

Over: TRIBUTARY TO PAINT BRANC

.4 MI W OF CHERRY HILL RD, Montgomery, MD

Built 2010 Load: 99.9 t ADT: 2,710

WISCONSIN AVENUE

Good

Over: BETHESDA METRO PED. TUNN

70 FT SOUTH OF MD 410, Montgomery, MD

Built 1984 Load: 99.9 t ADT: 40,769

EDISON PARK DRIVE

Good

Over: TRUCK LOADING DOCKS

0.4 MI NORTH OF MD 28, Montgomery, MD

Built 1968 Load: 99.9 t ADT: 130

SNOWDEN FARM PARKW

Good

Over: LITTLE SENECA CREEK

N. OF FREDERICK ROAD, Montgomery, MD

Built 2011 Load: 99.9 t ADT: 6,303

SNOWDEN FARM PARKW

Good

Over: TRIB TO LITTLE SENECA CR

N. OF FREDERICK ROAD, Montgomery, MD

Built 2011 Load: 99.9 t ADT: 5,795

FOREMAN BOULEVARD

Good

Over: TRIB TO LITTLE SENECA CR

E. OF FREDERICK ROAD, Montgomery, MD

Built 2011 Load: 99.9 t ADT: 3,500

WEST OLD BALTIMORE

Good

Over: CABIN BRANCH

0.5 MI EAST OF MD 121, Montgomery, MD

Built 2016 Load: 99.9 t ADT: 2,221

SERPENTINE WAY

Good

Over: TRIB TO PAINT BRANCH

0.7 MILES WEST OF US-29, Montgomery, MD

Built 1975 Load: 99.9 t ADT: 3,476

CENTURION WAY

Good

Over: SANDY BRANCH

3.3 MILES NORTH MD-190, Montgomery, MD

Built 2000 Load: 99.9 t ADT: 6,433

OBSERVATION DRIVE

Good

Over: TRIB TO LITTLE SENECA CR

0.3 MI. EAST OF I-270, Montgomery, MD

Built 1994 Load: 99.9 t ADT: 11,584

HOMECREST ROAD

Good

Over: NORTHWEST BRANCH TRIB

0.9 MI. E. OF MD 97, Montgomery, MD

Built 1972 Load: 99.9 t ADT: 105

UPSHIRE CIRCLE

Good

Over: SHADY BRANCH

.7 MI W OF MUDDY BR ROAD, Montgomery, MD

Built 1990 Load: 99.9 t ADT: 265

VICTORY FARM DRIVE

Good

Over: TRIBUTARY TO WHETSTONE R

0.3 MI N OF GIRARD ST, Montgomery, MD

Built 1981 Load: 99.9 t ADT: 3,667

CARNATION DRIVE

Good

Over: WATTS BRANCH TRIBUTARY

1.25 MI N OF MD 28, Montgomery, MD

Built 1969 Load: 99.9 t ADT: 480

MD 200

Good

Over: Mill Creek

4.98 mi west of MD 97, Montgomery, MD

Built 2008 Load: 99.9 t ADT: 42,498

MD 200

Good

Over: Mill Creek Tributary

4.56 mi west of MD 97, Montgomery, MD

Built 2008 Load: 99.9 t ADT: 42,498

Read our methodology - how this data is sourced, computed, and verified.

Related

Browse all → | Rankings →
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.