County profile · official public datasets

Bowman County, ND

69 public highway bridges tracked in the FHWA National Bridge Inventory: 65.2% rated Good, 31.9% Fair, 2.9% Poor.

69
Public bridges: 65.2%
Good condition: 2.9%
Poor condition

The verdict

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

Bowman County pairs a top-quartile lowest Poor-condition share among rated counties in the state with a newer average build year than the state inventory.

Top 21%
lowest Poor share in state: 2.9%
Poor-condition share: 69
public highway bridges: 1984
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.

Bowman County Bridge Snapshot

According to the Federal Highway Administration's 2024 National Bridge Inventory, Bowman County ranks #11 of 53 North Dakota counties with at least 5 public highway bridges on Poor-condition share (lower share ranks better; currently 2.9%). Bowman County, North Dakota contains 69 public highway bridges. Roughly 65.2% are rated “Good,” 31.9% “Fair,” and 2.9% “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

Public highway bridges in Bowman County

Good condition

65.2%

45 of 69 rated 7-9

Fair condition

31.9%

22 of 69 rated 5-6

Poor condition

2.9%

2 of 69 rated 4 or below

In-state Poor-share rank

#11 of 53

Among North Dakota counties with 5+ bridges, lower share ranks better

Condition distribution

Share of 69 NBI-tracked bridges by lowest applicable component rating.

Good

65.2% (45)

Fair

31.9% (22)

Poor

2.9% (2)

Bowman County's Poor-condition bridges carry 55 vehicle crossings a day

That is 0.3% of the county's reported daily bridge traffic on 2.9% of its bridges: Poor-condition structures carry less traffic than their share of the inventory. Each Poor bridge averages 28 crossings a day against 287 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 69 of 69 bridges in this county that report an average daily traffic count. Source: FHWA National Bridge Inventory, 2024 release.

39.1% of Bowman County's bridges have passed the 50-year mark

27 of the 69 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 65.2% 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 54.5% of the county's Poor-condition bridge traffic

Hamilton Street over Buffalo Creek, built 1958, carries 30 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 2-bridge count understates how much of the daily burden sits on a single crossing.

Share is of the 55 daily crossings on Poor-rated bridges that report a traffic count. Source: FHWA National Bridge Inventory, 2024 release.

1920s

1
1930s

3
1940s

1
1950s

2
1960s

13
1970s

8
1980s

10
1990s

10
2000s

13
2010s

8

What this shows Construction peaked in the 1960s, when 13 of the county's bridges still in the inventory were built, which is 18.8% of those with a recorded year. That cohort is now 55 to 64 years old in the 2024 inventory. Its average build year is 1984, 9 years newer than the North Dakota average of 1975.

How Bowman County compares with North Dakota's closest counties by inventory size

The 5 North Dakota counties nearest Bowman County in number of bridges, with their condition splits. Its 2.9% Poor share is the 2nd-lowest of these 6. Its average build year of 1984 against a peer-group mean of 1975 is 9 years newer.

Showing the 5 closest of 52 North Dakota counties eligible for comparison.

Bridge inventory size and condition shares for Bowman County and the 5 North Dakota counties closest to it in inventory size
County	Bridges	Good	Fair	Poor	Avg. built
Dunn County	74	62.2%	35.1%	2.7%	1988
Mercer County	72	40.3%	54.2%	5.6%	1975
Bowman County (this page)	69	65.2%	31.9%	2.9%	1984
Emmons County	67	65.7%	31.3%	3%	1975
Cavalier County	66	24.2%	50%	25.8%	1973
Hettinger County	64	34.4%	50%	15.6%	1963

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 Bowman 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 Bowman County, both outside North Dakota so the neighborhoods are not the same-state size table above.

Similar inventory size

Nearest county inventories outside ND (69 bridges here).

Irwin County, GA · 69 bridges
Edwards County, KS · 69 bridges
Barry County, MI · 69 bridges
Maries County, MO · 69 bridges

Similar average build year

Nearest mean year-built outside ND (1984 here).

Hennepin County, MN · avg 1984 · 936 bridges
Duval County, FL · avg 1984 · 831 bridges
El Paso County, CO · avg 1984 · 686 bridges
Bell County, TX · avg 1984 · 660 bridges

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

All 69 Good 45 Fair 22 Poor 2

Good-condition bridges (45)

Sort:

Bowman County Bridge Snapshot

Condition distribution

Bowman County's Poor-condition bridges carry 55 vehicle crossings a day

39.1% of Bowman County's bridges have passed the 50-year mark

One structure carries 54.5% of the county's Poor-condition bridge traffic

How Bowman County compares with North Dakota's closest counties by inventory size

Nationwide counties with similar inventory size or average build year

Similar inventory size

Similar average build year

Good-condition bridges (45)

US HIGHWAY 12

ND HIGHWAY 67

US HIGHWAY 12

146th Avenue

COUNTY ROAD

93rd St SW

144th Street

130th Ave SW

US HIGHWAY 85

139th Ave. SW

99th St SW

163rd Avenue

US HIGHWAY 85

GRIFFIN ROAD

80th St SW

137TH AVENUE

92nd Street

150th Ave SW

141st Street

86th St SW

78TH STREET

161st Ave. SW

141ST AVENUE

ND HIGHWAY 67

163rd Avenue SW

149th Ave. SW

95th St. SW

US HIGHWAY 85

81ST STREET

87th St. SW

US HIGHWAY 12

130th St SW

Camp Crook Rd.

DIAL HOUSE ROAD

147TH AVENUE

132ND AVENUE

133RD AVENUE

ND HIGHWAY 67

COUNTY HIGHWAY

COUNTY HIGHWAY

82nd Street

158th Avenue SW

152nd AVENUE

137TH AVENUE

US HIGHWAY 12

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