County profile · official public datasets

Howard County, MD

309 public highway bridges tracked in the FHWA National Bridge Inventory: 35.9% rated Good, 58.3% Fair, 5.8% Poor.

309
Public bridges
35.9%
Good condition
5.8%
Poor condition

The verdict

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

Howard 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.

16th
of 24 on Poor share
5.8%
Poor-condition share
309
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.

Howard County Bridge Snapshot

According to the Federal Highway Administration's 2024 National Bridge Inventory, Howard County ranks #16 of 24 Maryland counties with at least 5 public highway bridges on Poor-condition share (lower share ranks better; currently 5.8%). Howard County, Maryland contains 309 public highway bridges. Roughly 35.9% are rated “Good,” 58.3% “Fair,” and 5.8% “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

309

Public highway bridges in Howard County

Good condition

35.9%

111 of 309 rated 7-9

Fair condition

58.3%

180 of 309 rated 5-6

Poor condition

5.8%

18 of 309 rated 4 or below

In-state Poor-share rank

#16 of 24

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

Condition distribution

Share of 309 NBI-tracked bridges by lowest applicable component rating.

Good
35.9% (111)
Fair
58.3% (180)
Poor
5.8% (18)

Howard County's Poor-condition bridges carry 46,181 vehicle crossings a day

That is 0.5% of the county's reported daily bridge traffic on 5.8% of its bridges: Poor-condition structures carry less traffic than their share of the inventory. Each Poor bridge averages 2,566 crossings a day against 20,094 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 308 of 309 bridges in this county that report an average daily traffic count. Source: FHWA National Bridge Inventory, 2024 release.

46.9% of Howard County's bridges have passed the 50-year mark

145 of the 309 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 35.9% 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 23.7% of the county's Poor-condition bridge traffic

TAMAR DRIVE over UNNAMED STREAM, built 1970, carries 10,941 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 18-bridge count understates how much of the daily burden sits on a single crossing.

Share is of the 46,181 daily crossings on Poor-rated bridges that report a traffic count. Source: FHWA National Bridge Inventory, 2024 release.

When Howard County's bridges were built

309 bridges with a recorded construction year, grouped by decade

bridges

What this shows Construction peaked in the 1970s, when 81 of the county's bridges still in the inventory were built, which is 26.2% of those with a recorded year. That cohort is now 45 to 54 years old in the 2024 inventory. Its average build year is 1978, 6 years newer than the Maryland average of 1972.

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

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

The 5 Maryland counties nearest Howard County in number of bridges, with their condition splits. Its 5.8% Poor share is the 4th-lowest of these 6. Its average build year of 1978 against a peer-group mean of 1969 is 9 years newer.

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

Bridge inventory size and condition shares for Howard County and the 5 Maryland counties closest to it in inventory size
County Bridges Poor
Anne Arundel County 389 1.5%
Baltimore city County 374 8.6%
Howard County (this page) 309 5.8%
Washington County 300 4.7%
Harford County 275 4.7%
Allegany County 245 6.1%

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

Similar inventory size

Nearest county inventories outside MD (309 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 309 Good 111 Fair 180 Poor 18

Good-condition bridges (111)

RESORT ROAD

Good

Over: UNNAMED PERENNIAL STREAM

1.0 MI NORTH OF US 40, Howard, MD

Built 2019 ADT: 1,233

RESORT ROAD

Good

Over: UNNAMED INTERMITTENT STR

0.7 MI NORTH OF US 40, Howard, MD

Built 2019 ADT: 1,233

RIVER ROAD

Good

Over: TRIBUTARY TO PATAPSCO RI

0.6 MI E OF MD RTE 32, Howard, MD

Built 1975 Load: 21.8 t ADT: 1,160

MD 32 EB

Good

Over: CEDAR LANE

1.19 MILE NORTH OF US 29, Howard, MD

Built 1994 Load: 29.0 t ADT: 48,582

MD 32 WB

Good

Over: CEDAR LANE

1.19 MILE NORTH OF US 29, Howard, MD

Built 1994 Load: 29.0 t ADT: 48,582

US 1

Good

Over: MD 100

0.51 MILE NORTH OF MD 103, Howard, MD

Built 1994 Load: 30.4 t ADT: 35,932

MD 216

Good

Over: US 29

.16 M N OF ICE CRYSTAL DR, Howard, MD

Built 2001 Load: 31.7 t ADT: 17,672

US 29 RAMP 7

Good

Over: US 40 EBR

0.13 MILE EAST OF US 29, Howard, MD

Built 2012 Load: 32.4 t ADT: 14,400

LINDEN CHURCH ROAD

Good

Over: MD 32

750 E TEN OAKS ROAD, Howard, MD

Built 2013 Load: 32.4 t ADT: 4,275

MD 108

Good

Over: MD 32

0.09 M E OF TEN OAKS ROAD, Howard, MD

Built 1996 Load: 32.7 t ADT: 19,870

ROVER MILL ROAD

Good

Over: MIDDLE PATUXENT RIVER

0.6 Mile E of McEndree Rd, Howard, MD

Built 1970 Load: 32.7 t ADT: 100

TOLL HOUSE ROAD

Good

Over: HUDSON BRANCH

30 FT S OF FREDERICK RD, Howard, MD

Built 1967 Load: 32.7 t ADT: 200

SWIMMER ROW WAY

Good

Over: TRIB MIDDLE PATUXENT R

200 ft East of S Trotter, Howard, MD

Built 2000 Load: 32.7 t ADT: 50

HESPERUS DRIVE

Good

Over: TRIB TO WILDE LAKE

1/4 MI SOUTH OF MD 108, Howard, MD

Built 1972 Load: 32.7 t ADT: 50

ELLICOTT WOODS LN

Good

Over: TRIB TO BONNIE BR

At Worthington Way, Howard, MD

Built 1990 Load: 32.7 t ADT: 50

THUNDER HILL ROAD

Good

Over: UNNAMED STREAM

1/8 MI S of MD 108, Howard, MD

Built 1972 Load: 32.7 t ADT: 200

OLD STOCKBRIDGE DR

Good

Over: DEEP RUN

1/8 MI W of MD 103, Howard, MD

Built 1972 Load: 32.7 t ADT: 300

US 40 WB

Good

Over: IS 70

US 40 @ IS 70, Howard, MD

Built 1968 Load: 33.6 t ADT: 6,355

COLUMBIA ROAD

Good

Over: LITTLE PATUXENT RIVER

0.5 MI N OF L. PATUX PKWY, Howard, MD

Built 1987 Load: 33.6 t ADT: 6,934

MD 216

Good

Over: US 29

.16 M N OF ICE CRYSTAL DR, Howard, MD

Built 2001 Load: 34.0 t ADT: 17,672

TRIDELPHIA ROAD

Good

Over: MD 32

4.30 MI W OF MD 144, Howard, MD

Built 2020 Load: 34.3 t ADT: 7,200

KNIGHTS BRIDGE RD

Good

Over: HAMMONDS BRANCH

0.1 MI S LOCH LEVEN CT, Howard, MD

Built 1992 Load: 35.4 t ADT: 940

GUILFORD ROAD

Good

Over: MIDDLE PATUXENT RIVER

0.04 MI N BERGER RD, Howard, MD

Built 1982 Load: 35.8 t ADT: 8,192

FOUNDRY STREET

Good

Over: LITTLE PATUXENT RIVER

0.03 MI N OF GORMAN RD, Howard, MD

Built 1975 Load: 36.7 t ADT: 5,511

MD 732R

Good

Over: MD 32

0.17 M S OF GUILFORD ROAD, Howard, MD

Built 1991 Load: 37.2 t ADT: 15,761

GREAT STAR DRIVE

Good

Over: MD 32

1.15 MI E OF MD 108, Howard, MD

Built 1995 Load: 37.6 t ADT: 3,513

MD 32

Good

Over: RIV RD CSX PATAPSCO RIV

ON CARROLL COUNTY LINE, Howard, MD

Built 2003 Load: 37.6 t ADT: 19,240

STEPHENS ROAD

Good

Over: HAMMOND BRANCH

0.3 M N WHISKEY BOTTOM RD, Howard, MD

Built 2021 Load: 37.6 t ADT: 3,350

TWINSTREAM DRIVE

Good

Over: TRIB TO BONNIE BR

75 W of Bonnie Branch Rd, Howard, MD

Built 2000 Load: 38.1 t ADT: 25

MD 732R

Good

Over: CSX TRANS BROCK BRIDGE

ON ANNE ARUNDEL CO LINE, Howard, MD

Built 1990 Load: 39.0 t ADT: 15,761

WHISKEY BOTTOM RD

Good

Over: CSX RR TRACKS

ANNE ARUNDEL COUNTY LINE, Howard, MD

Built 1943 Load: 40.4 t ADT: 10,475

HOPKINS/GORMAN RD

Good

Over: US 29

OVER US 29, Howard, MD

Built 2001 Load: 40.8 t ADT: 7,207

MD 216 RAMP A (8)

Good

Over: MD 216

.78 MI S OF I-95, Howard, MD

Built 2003 Load: 40.8 t ADT: 3,691

MD 932B-BURNTWOODS

Good

Over: MD 32

0.051 M S OF TEN OAKS RD, Howard, MD

Built 2008 Load: 40.8 t ADT: 2,405

SANNER ROAD

Good

Over: TRIB OF MIDDLE PATUXENT

0.3 MI S PINDELL SCHOOL, Howard, MD

Built 2003 Load: 41.7 t ADT: 2,493

MURRAY HILL ROAD

Good

Over: MIDDLE PATUXENT RIVER

0.1 MI S VOLLMERHAUSEN RD, Howard, MD

Built 1988 Load: 42.6 t ADT: 3,576

STEVENS FOREST ROA

Good

Over: LITTLE PATUXENT RIVER

0.1 MI E OF US 29, Howard, MD

Built 1990 Load: 42.6 t ADT: 5,350

SOUTH ENTRANCE ROA

Good

Over: LITTLE PATUXENT RIVER

0.08 MILE WEST OF US 29, Howard, MD

Built 2004 Load: 43.1 t ADT: 4,200

CASTLEBRIDGE ROAD

Good

Over: UNNAMED STREAM

400 N OF HOMEWOOD RD, Howard, MD

Built 1995 Load: 43.1 t ADT: 50

BROKEN LAND PKWY

Good

Over: LITTLE PATUXENT RIVER

0.31 MI S OF US 29, Howard, MD

Built 1992 Load: 43.5 t ADT: 32,730

MD 32

Good

Over: BR OF MIDDLE PATUXENT RI

1.5 MI N OF BURNTWOODS RD, Howard, MD

Built 2020 Load: 43.7 t ADT: 29,475

ACCESS ROAD

Good

Over: HUDSON BRANCH

FREDERICK RD & ROGERS AVE, Howard, MD

Built 2003 Load: 44.4 t ADT: 10

US 29 RAMP D(1)

Good

Over: US 29

1.77 MILES NORTH OF MD 32, Howard, MD

Built 1991 Load: 45.4 t ADT: 10,581

MD 100

Good

Over: SNOWDEN RIVER PARKWAY

0.86 MILE WEST OF MD 103, Howard, MD

Built 1998 Load: 45.8 t ADT: 82,092

MD 100

Good

Over: SNOWDEN RIVER PARKWAY

0.86 MILE WEST OF MD 103, Howard, MD

Built 1997 Load: 45.8 t ADT: 82,092

ROGERS AVENUE

Good

Over: SUCKER BRANCH

0.4 MI N OF US RTE 40, Howard, MD

Built 1988 Load: 45.8 t ADT: 9,270

BROKEN LAND PKWY

Good

Over: LITTLE PATUXENT RIVER

0.125 MI S OF MD RTE 32, Howard, MD

Built 1986 Load: 46.7 t ADT: 21,288

Kerby Hill Rd.

Good

Over: MD 210 Service Rd.

1.5 MILE SOUTH OF I-495, Howard, MD

Built 2021 Load: 47.6 t ADT: 6,525

MD 100

Good

Over: EXECUTIVE PARK DRIVE

0.91 MILE WEST OF MD 104, Howard, MD

Built 1998 Load: 49.9 t ADT: 79,752

MD 100

Good

Over: CSX RR OCONNOR RD

0.24 M W OF AA CO LINE, Howard, MD

Built 1996 Load: 49.9 t ADT: 83,402

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

Related

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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.