County profile · official public datasets

Sumner County, KS

659 public highway bridges tracked in the FHWA National Bridge Inventory: 50.2% rated Good, 47.2% Fair, 2.6% Poor.

659
Public bridges: 50.2%
Good condition: 2.6%
Poor condition

The verdict

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

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

Top 31%
lowest Poor share in state: 2.6%
Poor-condition share: 659
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.

Sumner County Bridge Snapshot

According to the Federal Highway Administration's 2024 National Bridge Inventory, Sumner County ranks #32 of 104 Kansas counties with at least 5 public highway bridges on Poor-condition share (lower share ranks better; currently 2.6%). Sumner County, Kansas contains 659 public highway bridges. Roughly 50.2% are rated “Good,” 47.2% “Fair,” and 2.6% “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

659

Public highway bridges in Sumner County

Good condition

50.2%

331 of 659 rated 7-9

Fair condition

47.2%

311 of 659 rated 5-6

Poor condition

2.6%

17 of 659 rated 4 or below

In-state Poor-share rank

#32 of 104

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

Condition distribution

Share of 659 NBI-tracked bridges by lowest applicable component rating.

Good

50.2% (331)

Fair

47.2% (311)

Poor

2.6% (17)

Sumner County's Poor-condition bridges carry 14,396 vehicle crossings a day

That is 3% of the county's reported daily bridge traffic on 2.6% of its bridges: Poor-condition structures carry more traffic than their share of the inventory. Each Poor bridge averages 847 crossings a day against 841 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 659 of 659 bridges in this county that report an average daily traffic count. Source: FHWA National Bridge Inventory, 2024 release.

37.6% of Sumner County's bridges have passed the 50-year mark

248 of the 659 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 50.2% 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 64.9% of the county's Poor-condition bridge traffic

I-35 HWY NB (KTA) over LOCAL ROAD, built 1956, carries 9,350 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 17-bridge count understates how much of the daily burden sits on a single crossing.

Share is of the 14,396 daily crossings on Poor-rated bridges that report a traffic count. Source: FHWA National Bridge Inventory, 2024 release.

1900s

3
1910s

1
1920s

24
1930s

41
1940s

7
1950s

92
1960s

58
1970s

54
1980s

107
1990s

110
2000s

118
2010s

33
2020s

11

What this shows Construction peaked in the 2000s, when 118 of the county's bridges still in the inventory were built, which is 17.9% of those with a recorded year. That cohort is now 15 to 24 years old in the 2024 inventory. Its average build year is 1978, 6 years newer than the Kansas average of 1972.

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

The 5 Kansas counties nearest Sumner County in number of bridges, with their condition splits. Its 2.6% Poor share is the 3rd-lowest of these 6. Its average build year of 1978 against a peer-group mean of 1980 is in line with the group.

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

Bridge inventory size and condition shares for Sumner County and the 5 Kansas counties closest to it in inventory size
County	Bridges	Good	Fair	Poor	Avg. built
Johnson County	781	75%	23.6%	1.4%	1992
Sumner County (this page)	659	50.2%	47.2%	2.6%	1978
Butler County	591	59.2%	34.7%	6.1%	1966
McPherson County	586	66.6%	32.8%	0.7%	1979
Reno County	573	51.8%	42.1%	6.1%	1980
Shawnee County	563	62.9%	34.1%	3%	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 Sumner 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 Sumner County, both outside Kansas so the neighborhoods are not the same-state size table above.

Similar inventory size

Nearest county inventories outside KS (659 bridges here).

Salt Lake County, UT · 659 bridges
Bell County, TX · 660 bridges
Alameda County, CA · 658 bridges
Lancaster County, NE · 661 bridges

Similar average build year

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

Orange County, CA · avg 1978 · 1,164 bridges
Allen County, IN · avg 1978 · 613 bridges
Livingston County, IL · avg 1978 · 579 bridges
Buncombe County, NC · avg 1978 · 555 bridges

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

All 659 Good 331 Fair 311 Poor 17

Good-condition bridges (331)

Sort:

Sumner County Bridge Snapshot

Condition distribution

Sumner County's Poor-condition bridges carry 14,396 vehicle crossings a day

37.6% of Sumner County's bridges have passed the 50-year mark

One structure carries 64.9% of the county's Poor-condition bridge traffic

How Sumner 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

Good-condition bridges (331)

E. 70th St. S.

E. 120th Ave.

LOCAL 52-39-6

E. 100th St. S.

N. Caldwell Rd.

LOCAL 56-43-8

LOCAL 11-64-5

LOCAL 54-43-5

US166 HWY

W. 140th St. S.

LOCAL 46-29-3

LOCAL 21-34-8

K49 HWY

RS 788 17-56-5

LOCAL 22-5-5

LOCAL 15-4-9

LOCAL 6-15-1

LOCAL 15-2-9

MINOR 33-34-3

W. 60th St. S.

LOCAL 0-41-6

LOCAL 50-45-1

LOCAL 24-47-2

LOCAL 50-49-1

LOCAL 42-57-9

LOCAL 54-59-1

W. 119th St.

MILL ST. BR. 5

HARVEY AVE. BR. 9

US160 HWY

US160 HWY

W. 50th Ave. N.

US166 HWY

US166 HWY

LOCAL 40-23-5

S. 130th St. E.

K-15 HWY

LOCAL 4-15-2

MINOR 4-63-2

RS1342 (40th St)

K55 HWY

US166 HWY

US166 HWY

LOCAL 42-9-9

I-35 HWY SB (KTA)

I-35 HWY NB (KTA)

MULVANE IC RAMP

LOCAL 16-63-7

RS 645 42-41-0

LOCAL 33-52-7

Related