County profile · official public datasets

Doniphan County, KS

129 public highway bridges tracked in the FHWA National Bridge Inventory: 50.4% rated Good, 41.1% Fair, 8.5% Poor.

129
Public bridges: 50.4%
Good condition: 8.5%
Poor condition

The verdict

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

Doniphan 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.

83rd
of 104 on Poor share: 8.5%
Poor-condition share: 129
public highway bridges: 1977
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.

Doniphan County Bridge Snapshot

According to the Federal Highway Administration's 2024 National Bridge Inventory, Doniphan County ranks #83 of 104 Kansas counties with at least 5 public highway bridges on Poor-condition share (lower share ranks better; currently 8.5%). Doniphan County, Kansas contains 129 public highway bridges. Roughly 50.4% are rated “Good,” 41.1% “Fair,” and 8.5% “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

129

Public highway bridges in Doniphan County

Good condition

50.4%

65 of 129 rated 7-9

Fair condition

41.1%

53 of 129 rated 5-6

Poor condition

8.5%

11 of 129 rated 4 or below

In-state Poor-share rank

#83 of 104

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

Condition distribution

Share of 129 NBI-tracked bridges by lowest applicable component rating.

Good

50.4% (65)

Fair

41.1% (53)

Poor

8.5% (11)

Doniphan County's Poor-condition bridges carry 3,328 vehicle crossings a day

That is 3.5% of the county's reported daily bridge traffic on 8.5% of its bridges: Poor-condition structures carry less traffic than their share of the inventory. Each Poor bridge averages 303 crossings a day against 950 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 129 of 129 bridges in this county that report an average daily traffic count. Source: FHWA National Bridge Inventory, 2024 release.

39.5% of Doniphan County's bridges have passed the 50-year mark

51 of the 129 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 50.4% 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 73.2% of the county's Poor-condition bridge traffic

RS 2128 over MISSION CREEK, built 1939, carries 2,435 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 11-bridge count understates how much of the daily burden sits on a single crossing.

Share is of the 3,328 daily crossings on Poor-rated bridges that report a traffic count. Source: FHWA National Bridge Inventory, 2024 release.

1900s

2
1910s

2
1920s

3
1930s

7
1940s

2
1950s

11
1960s

14
1970s

17
1980s

22
1990s

24
2000s

14
2010s

8
2020s

3

What this shows Construction peaked in the 1990s, when 24 of the county's bridges still in the inventory were built, which is 18.6% of those with a recorded year. That cohort is now 25 to 34 years old in the 2024 inventory. Its average build year is 1977, 5 years newer than the Kansas average of 1972.

How Doniphan County compares with Kansas's closest counties by inventory size

The 5 Kansas counties nearest Doniphan County in number of bridges, with their condition splits. Its 8.5% Poor share is the 4th-lowest of these 6. Its average build year of 1977 against a peer-group mean of 1973 is in line with the group.

Showing the 5 closest of 103 Kansas counties eligible for comparison.

Bridge inventory size and condition shares for Doniphan County and the 5 Kansas counties closest to it in inventory size
County	Bridges	Good	Fair	Poor	Avg. built
Graham County	142	52.8%	39.4%	7.7%	1968
Geary County	140	46.4%	43.6%	10%	1972
Chautauqua County	130	41.5%	47.7%	10.8%	1964
Doniphan County (this page)	129	50.4%	41.1%	8.5%	1977
Stafford County	119	50.4%	46.2%	3.4%	1979
Pratt County	118	65.3%	34.7%	0%	1981

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

Similar inventory size

Nearest county inventories outside KS (129 bridges here).

Clay County, AL · 129 bridges
Cross County, AR · 129 bridges
Lake County, CA · 129 bridges
Lincoln County, CO · 129 bridges

Similar average build year

Nearest mean year-built outside KS (1977 here).

San Diego County, CA · avg 1977 · 1,632 bridges
King County, WA · avg 1977 · 1,238 bridges
Riverside County, CA · avg 1977 · 1,117 bridges
Shelby County, TN · avg 1977 · 1,077 bridges

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

All 129 Good 65 Fair 53 Poor 11

All bridges (129)

Sort:

MINOR T-625-3

Fair

Over: SMITH CREEK

4.4N 2.8E OF BLAIR, Doniphan, KS

Built 1994 Load: 39.3 t ADT: 35

MINOR T-143-1

Fair

Over: COLD RYAN BRANCH

TRIB N.BR. INDEPENDENCE, Doniphan, KS

Built 1993 Load: 40.2 t ADT: 30

K20 HWY

Fair

Over: N BRANCH INDEPENDENCE CR

7.30 M NE BROWN COLN, Doniphan, KS

Doniphan County Bridge Snapshot

Condition distribution

Doniphan County's Poor-condition bridges carry 3,328 vehicle crossings a day

39.5% of Doniphan County's bridges have passed the 50-year mark

One structure carries 73.2% of the county's Poor-condition bridge traffic

How Doniphan County compares with Kansas's closest counties by inventory size

Nationwide counties with similar inventory size or average build year

Similar inventory size

Similar average build year

All bridges (129)

MINOR T-625-3

MINOR T-143-1

K20 HWY

RS 28

RS 827 T-827-6

RS 828

K120 HWY

US36 HWY

US36 HWY

CO LINE LOCAL RD

US36 HWY

LOCAL T-41-1

K-7 HWY

IRR BIA ROUTE 826

LOCAL T-419-1

RS 201

LOCAL T-29-1

MINOR T-827-1

LOCAL T-734-1

RS 827 T-827-7

LOCAL T-616-3

RS 202

MINOR T-35-3

LOCAL T-216-1

LOCAL T-332-1

US-36 HWY WB

US-36 HWY EB

LOCAL T-37-1

RS 28

MINOR T-35-2

LOCAL T-410-1

LOCAL T-45-1

LOCAL T-616-1

LOCAL T-616-2

LOCAL T-616-4

LOCAL T-418-2

LOCAL T-744-1

LOCAL T-623-1

BIA IRR RTE 826

US36 K7 HWY

LOCAL T-21-1

US36 HWY EB

US36 K7 HWY

RS 827 T-827-4

LOCAL T-216-2

WB US-36 HWY

LOCAL T-214-1

MINOR T-251-1

US36 HWY

LOCAL T-109-1

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