Total bridges
486
Public highway bridges in Frederick County
County profile · official public datasets
Frederick County, MD
486 public highway bridges tracked in the FHWA National Bridge Inventory: 43.2% rated Good, 54.1% Fair, 2.7% Poor.
- 486
- Public bridges
- 43.2%
- Good condition
- 2.7%
- Poor condition
The verdict
According to the Federal Highway Administration's 2024 National Bridge Inventory.
Frederick County posts a top-quartile lowest Poor-condition share among rated counties in the state across mid-size county bridge inventory.
- Top 25%
- lowest Poor share in state
- 2.7%
- Poor-condition share
- 486
- public highway bridges
- 1971
- 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.
Frederick County Bridge Snapshot
According to the Federal Highway Administration's 2024 National Bridge Inventory, Frederick County ranks #6 of 24 Maryland counties with at least 5 public highway bridges on Poor-condition share (lower share ranks better; currently 2.7%). Frederick County, Maryland contains 486 public highway bridges. Roughly 43.2% are rated “Good,” 54.1% “Fair,” and 2.7% “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
43.2%
210 of 486 rated 7-9
Fair condition
54.1%
263 of 486 rated 5-6
Poor condition
2.7%
13 of 486 rated 4 or below
In-state Poor-share rank
#6 of 24
Among Maryland counties with 5+ bridges, lower share ranks better
Condition distribution
Share of 486 NBI-tracked bridges by lowest applicable component rating.
Good 43.2% (210)
Fair 54.1% (263)
Poor 2.7% (13)
Frederick County's Poor-condition bridges carry 17,033 vehicle crossings a day
That is 0.3% of the county's reported daily bridge traffic on 2.7% of its bridges: Poor-condition structures carry less traffic than their share of the inventory. Each Poor bridge averages 1,310 crossings a day against 7,809 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 486 of 486 bridges in this county that report an average daily traffic count. Source: FHWA National Bridge Inventory, 2024 release.
47.5% of Frederick County's bridges have passed the 50-year mark
231 of the 486 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 43.2% 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 39.6% of the county's Poor-condition bridge traffic
SHOOKSTOWN ROAD over CARROLL CREEK, built 1911, carries 6,750 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 13-bridge count understates how much of the daily burden sits on a single crossing.
Share is of the 17,033 daily crossings on Poor-rated bridges that report a traffic count. Source: FHWA National Bridge Inventory, 2024 release.
When Frederick County's bridges were built
486 bridges with a recorded construction year, grouped by decade
- pre-1900 12
Built before 1900
12 bridges
- 1900s 9
1900–1909
9 bridges
- 1910s 8
1910–1919
8 bridges
- 1920s 23
1920–1929
23 bridges
- 1930s 23
1930–1939
23 bridges
- 1940s 2
1940–1949
2 bridges
- 1950s 37
1950–1959
37 bridges
- 1960s
1960–1969
75 bridges
- 1970s
1970–1979
76 bridges
- 1980s
1980–1989
104 bridges
- 1990s
1990–1999
46 bridges
- 2000s 39
2000–2009
39 bridges
- 2010s 23
2010–2019
23 bridges
- 2020s 9
2020–2029
9 bridges
What this shows Construction peaked in the 1980s, when 104 of the county's bridges still in the inventory were built, which is 21.4% of those with a recorded year. That cohort is now 35 to 44 years old in the 2024 inventory. Its average build year (1971) matches the Maryland average (1972).
How Frederick County compares with Maryland's closest counties by inventory size
The 5 Maryland counties nearest Frederick County in number of bridges, with their condition splits. Its 2.7% Poor share is the 2nd-lowest of these 6. Its average build year of 1971 against a peer-group mean of 1975 is in line with the group.
Showing the 5 closest of 23 Maryland counties eligible for comparison.
| County | Bridges | Good | Fair | Poor | Avg. built |
|---|---|---|---|---|---|
| Prince George's County | 576 | 36.6% | 60.2% | 3.1% | 1976 |
| Montgomery County | 515 | 38.8% | 56.3% | 4.9% | 1978 |
| Frederick County (this page) | 486 | 43.2% | 54.1% | 2.7% | 1971 |
| Anne Arundel County | 389 | 32.6% | 65.8% | 1.5% | 1980 |
| Baltimore city County | 374 | 16% | 75.4% | 8.6% | 1964 |
| Howard County | 309 | 35.9% | 58.3% | 5.8% | 1978 |
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 Frederick 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 Frederick County, both outside Maryland so the neighborhoods are not the same-state size table above.
Similar inventory size
Nearest county inventories outside MD (486 bridges here).
- St. Clair County, IL · 486 bridges
- Cattaraugus County, NY · 484 bridges
- Black Hawk County, IA · 489 bridges
- Suffolk County, MA · 489 bridges
Similar average build year
Nearest mean year-built outside MD (1971 here).
- Wayne County, MI · avg 1971 · 1,026 bridges
- Washington County, PA · avg 1971 · 655 bridges
- Linn County, OR · avg 1971 · 566 bridges
- Monmouth County, NJ · avg 1971 · 505 bridges
Source: FHWA National Bridge Inventory, 2024 release. Peers floor at 10 bridges so stub inventories cannot own the match.
Fair-condition bridges (263)
MONTEVUE LANE
FairOver: CARROLL CREEK
1.1 MI. W OF US 15, Frederick, MD
Built 1995 Load: 30.4 t ADT: 9,791
MD 180
FairOver: BALLENGER CREEK
1.74 MILES WEST OF IS 70, Frederick, MD
Built 1925 Load: 30.8 t ADT: 3,850
MD 550
FairOver: MONOCACY RIVER
2.68 MILES N OF MD 194, Frederick, MD
Built 1967 Load: 30.8 t ADT: 3,691
MD 28
FairOver: MONOCACY RIVER
0.98 MI W OF MONT CO, Frederick, MD
Built 1931 Load: 31.3 t ADT: 9,175
BIGGS FORD ROAD
FairOver: MONOCACY RIVER
0.55 MI E OF US RTE 15, Frederick, MD
Built 1970 Load: 31.3 t ADT: 6,393
MD 28
FairOver: TUSCARORA CREEK
1.85 MILES WEST OF MD 85, Frederick, MD
Built 2007 Load: 32.2 t ADT: 3,212
US 15
FairOver: LITTLE HUNTING CREEK
.87 MILE NORTH OF MD 806A, Frederick, MD
Built 1962 Load: 32.7 t ADT: 30,800
US 40
FairOver: MIDDLE CREEK
0.12 MILE EAST OF MD 17, Frederick, MD
Built 1936 Load: 32.7 t ADT: 5,522
US 15 SBR
FairOver: FISHING CREEK
0.07 MI N OF POWELL RD, Frederick, MD
Built 1961 Load: 32.7 t ADT: 43,080
US 15 SB
FairOver: TOMS CREEK
0.65 MILE N OF US 15BU, Frederick, MD
Built 1965 Load: 32.7 t ADT: 18,340
US 40 MEDIAN CROSS
FairOver: ROCK CREEK
0.28 M W OF BOWERS ROAD, Frederick, MD
Built 1969 Load: 32.7 t ADT: 25
US 15/340
FairOver: BALLENGER CREEK
1.95 MILES SOUTH OF IS 70, Frederick, MD
Built 1968 Load: 32.7 t ADT: 53,991
MD 75
FairOver: BENS BRANCH
0.19 MI S OF MD 874C, Frederick, MD
Built 1964 Load: 32.7 t ADT: 10,783
MD 26
FairOver: LINGANORE CREEK
0.22 M W OF BR NO 1016800, Frederick, MD
Built 1950 Load: 32.7 t ADT: 5,482
MD 26
FairOver: BRANCH OF LINGANORE CREE
0.58 M W ALBAUGH ROAD, Frederick, MD
Built 1950 Load: 32.7 t ADT: 5,272
MD 550
FairOver: FRIENDS CREEK
0.15 M S OF BENTZEL ROAD, Frederick, MD
Built 1981 Load: 32.7 t ADT: 7,861
LEGORE BRIDGE ROAD
FairOver: MONOCACY RIVER
3 MI N OF WOODSBORO, Frederick, MD
Built 1903 Load: 32.7 t ADT: 2,045
PARK MILLS ROAD
FairOver: BENNETT CREEK
2.75 MI SOUTH OF MD 80, Frederick, MD
Built 1965 Load: 32.7 t ADT: 674
KEY PARKWAY
FairOver: ROCK CREEK
500 W OF WILLOWDALE DR., Frederick, MD
Built 1990 Load: 32.7 t ADT: 3,560
COLLEGE AVENUE
FairOver: CARROLL CREEK FLOODPLAIN
0.2 MI NORTH OF MD 144, Frederick, MD
Built 1992 Load: 32.7 t ADT: 1,652
NORTH McCAIN DRIVE
FairOver: ROCK CREEK
0.2 MI. NORTH OF US 40, Frederick, MD
Built 1996 Load: 32.7 t ADT: 9,790
CHRISTOPHERS CROSS
FairOver: EDISON BRANCH
2.7 MI. WEST OF US 15, Frederick, MD
Built 1989 Load: 32.7 t ADT: 4,108
HAYWARD ROAD
FairOver: OPOSSUM BRANCH
0.7 MILES WEST OF US 15, Frederick, MD
Built 1990 Load: 32.7 t ADT: 6,712
TUSCANNEY DRIVE
FairOver: EDISON BRANCH
1.3 MI WEST OF US 15, Frederick, MD
Built 1998 Load: 32.7 t ADT: 4,027
BIGGS FORD ROAD
FairOver: DUBLIN BRANCH
1.5 MI E OF US RTE 15, Frederick, MD
Built 2004 Load: 32.7 t ADT: 3,911
ELMER DERR ROAD
FairOver: US 15
0.7 MI W OF US 340, Frederick, MD
Built 1969 Load: 33.1 t ADT: 999
MD 75
FairOver: BUSH CREEK
.65 MILE SOUTH OF MD 75FB, Frederick, MD
Built 1972 Load: 33.6 t ADT: 6,492
LIMESTONE LANE
FairOver: BR OF HOLLOW CREEK
AT BEECHTREE LANE INTERSC, Frederick, MD
Built 1960 Load: 33.6 t ADT: 50
MD 85
FairOver: ROCKY FOUNTAIN RUN
0.03 MILE NORTH OF MD 880, Frederick, MD
Built 1929 Load: 34.0 t ADT: 6,713
IS 270
FairOver: CSX TRANSPORTATION
1.0 MILE SOUTH OF MD 85, Frederick, MD
Built 1950 Load: 34.0 t ADT: 80,340
MD 75
FairOver: FAHRNEY BRANCH
0.43 MILE SOUTH OF MD 80, Frederick, MD
Built 1933 Load: 34.5 t ADT: 7,952
LANDER ROAD
FairOver: US 340
@ US 340, Frederick, MD
Built 1965 Load: 34.9 t ADT: 2,734
MD 144FA
FairOver: MONOCACY RIVER
1.04 MILE EAST OF IS 70, Frederick, MD
Built 1955 Load: 35.4 t ADT: 13,861
MD 77
FairOver: BR OF HUNTING CREEK
2.72 MI E OF WASH CO, Frederick, MD
Built 1971 Load: 35.4 t ADT: 3,271
ANNANDALE ROAD
FairOver: TOMS CREEK
0.62 MI W OF EMMITSBURG, Frederick, MD
Built 1980 Load: 35.4 t ADT: 1,505
ARNOLDTOWN ROAD
FairOver: BROAD RUN
0.2 MI N PICNIC WOODS RD, Frederick, MD
Built 1982 Load: 35.4 t ADT: 339
WWTP ROAD
FairOver: CARROLL CREEK
1.8 MI EAST OF MD 355, Frederick, MD
Built 1936 Load: 35.4 t ADT: 3,813
W. COLLEGE TERRACE
FairOver: CARROLL CREEK
0.2 MI NORTH OF MD 144, Frederick, MD
Built 1933 Load: 35.4 t ADT: 4,060
MT PHILLIP ROAD
FairOver: IS 70
1.77 MI W OF MD 180, Frederick, MD
Built 1967 Load: 35.8 t ADT: 5,102
US 40
FairOver: TRIB TO HAWBOTTOM BRANCH
0.29 MI E OF HOLLOW ROAD, Frederick, MD
Built 1936 Load: 36.3 t ADT: 5,522
ST MARKS ROAD
FairOver: US 340
0.96 MI W OF MD 180, Frederick, MD
Built 1964 Load: 36.3 t ADT: 53
DOUBS ROAD
FairOver: TUSCARORA CREEK
1.23 MI W OF NEW DESIGN R, Frederick, MD
Built 1950 Load: 36.3 t ADT: 327
MD 75
FairOver: LINGANORE CREEK
0.73 MI N OF MD 75FC, Frederick, MD
Built 1968 Load: 36.7 t ADT: 4,752
IS 70 EBR
FairOver: US 40AL
0.28 M E OF BR NO 1014500, Frederick, MD
Built 1967 Load: 37.2 t ADT: 74,920
BARTHOLOWS ROAD
FairOver: IS 70 CSX TRANSPORTATIO
2.26 MI E OF MD 75, Frederick, MD
Built 1974 Load: 37.2 t ADT: 3,994
SOUTH MARKET STREE
FairOver: CARROLL CREEK
510 SOUTH OF MD 144, Frederick, MD
Built 1988 Load: 37.2 t ADT: 8,900
US 340 WBR
FairOver: S MOUNTAIN ROAD
0.27 MILE EAST OF MD 180, Frederick, MD
Built 1964 Load: 37.6 t ADT: 23,492
MD 77
FairOver: OWENS CREEK
0.02 MI W OF FRUSHOUR RD, Frederick, MD
Built 1932 Load: 38.1 t ADT: 3,131
MD 180
FairOver: CATOCTIN CREEK
0.55 MILE EAST OF MD 872, Frederick, MD
Built 1928 Load: 38.1 t ADT: 4,580
IS 70 WBR
FairOver: US 40 ALT
0.28 M E OF BR NO 1014500, Frederick, MD
Built 1967 Load: 38.1 t ADT: 74,920
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.