County profile · official public datasets

Harper County, KS

372 public highway bridges tracked in the FHWA National Bridge Inventory: 25% rated Good, 65.3% Fair, 9.7% Poor.

372
Public bridges: 25%
Good condition: 9.7%
Poor condition

The verdict

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

Harper County pairs a higher-than-median Poor-condition share among rated counties in the state with an older average build year than the state inventory.

90th
of 104 on Poor share: 9.7%
Poor-condition share: 372
public highway bridges: 1965
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.

Harper County Bridge Snapshot

According to the Federal Highway Administration's 2024 National Bridge Inventory, Harper County ranks #90 of 104 Kansas counties with at least 5 public highway bridges on Poor-condition share (lower share ranks better; currently 9.7%). Harper County, Kansas contains 372 public highway bridges. Roughly 25% are rated “Good,” 65.3% “Fair,” and 9.7% “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.

Total bridges

372

Public highway bridges in Harper County

Good condition

25%

93 of 372 rated 7-9

Fair condition

65.3%

243 of 372 rated 5-6

Poor condition

9.7%

36 of 372 rated 4 or below

In-state Poor-share rank

#90 of 104

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

Condition distribution

Share of 372 NBI-tracked bridges by lowest applicable component rating.

Good

25% (93)

Fair

65.3% (243)

Poor

9.7% (36)

Harper County's Poor-condition bridges carry 3,726 vehicle crossings a day

That is 5.2% of the county's reported daily bridge traffic on 9.7% of its bridges: Poor-condition structures carry less traffic than their share of the inventory. Each Poor bridge averages 104 crossings a day against 552 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 372 of 372 bridges in this county that report an average daily traffic count. Source: FHWA National Bridge Inventory, 2024 release.

66.7% of Harper County's bridges have passed the 50-year mark

248 of the 372 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 25% 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 49.4% of the county's Poor-condition bridge traffic

US160 HWY over SAND CREEK, built 1956, carries 1,840 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 36-bridge count understates how much of the daily burden sits on a single crossing.

Share is of the 3,726 daily crossings on Poor-rated bridges that report a traffic count. Source: FHWA National Bridge Inventory, 2024 release.

1910s

4
1920s

12
1930s

61
1940s

46
1950s

35
1960s

51
1970s

55
1980s

31
1990s

19
2000s

41
2010s

16
2020s

1

What this shows Construction peaked in the 1930s, when 61 of the county's bridges still in the inventory were built, which is 16.4% of those with a recorded year. That cohort is now 85 to 94 years old in the 2024 inventory. Its average build year is 1965, 7 years older than the Kansas average of 1972.

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

The 5 Kansas counties nearest Harper County in number of bridges, with their condition splits. Its 9.7% Poor share is the 6th-lowest of these 6. Its average build year of 1965 against a peer-group mean of 1976 is 11 years older.

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

Bridge inventory size and condition shares for Harper County and the 5 Kansas counties closest to it in inventory size
County	Bridges	Good	Fair	Poor	Avg. built
Kingman County	391	48.3%	45.8%	5.9%	1976
Dickinson County	375	47.7%	47.2%	5.1%	1974
Harvey County	372	57.3%	35.5%	7.3%	1971
Harper County (this page)	372	25%	65.3%	9.7%	1965
Saline County	369	68.6%	29.5%	1.9%	1971
Nemaha County	359	41.5%	49%	9.5%	1986

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

Similar inventory size

Nearest county inventories outside KS (372 bridges here).

Clinton County, IA · 372 bridges
Johnson County, IA · 372 bridges
Wharton County, TX · 372 bridges
Solano County, CA · 373 bridges

Similar average build year

Nearest mean year-built outside KS (1965 here).

Windsor County, VT · avg 1965 · 483 bridges
Bedford County, PA · avg 1965 · 417 bridges
Crawford County, PA · avg 1965 · 399 bridges
Columbia County, PA · avg 1965 · 271 bridges

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

All 372 Good 93 Fair 243 Poor 36

Good-condition bridges (93)

Sort:

Harper County Bridge Snapshot

Condition distribution

Harper County's Poor-condition bridges carry 3,726 vehicle crossings a day

66.7% of Harper County's bridges have passed the 50-year mark

One structure carries 49.4% of the county's Poor-condition bridge traffic

How Harper 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 (93)

RS 301 NE 100 AVE

NW 120 RD

LOCAL Q.6-16.5

RS 302 NW 100 RD

SW 60th Road

NW 120th Ave.

NW 70 AVE

NW 60 AVE

NW 40 AVE

NE 30th Ave.

NW 150th Road

RS 296 (NW 100 AVE

NW 30 Rd

NW 120 Ave

LOCAL L.6-20.1

SE 70th Rd RS 299

SE 90th Road

NW 90 RD 8.0-O.8

NE 70 RD

US160 HWY

K44 HWY

K44 HWY

RS 302 NW 100 RD

NE 120 RD

NE 110 RD Z.1-6.0

K44 HWY

US160 HWY

US160 HWY

RS 302 NW 100 Rd

SE 30th RD Y.1-20

SW 15 AVE

K2 HWY

US160 HWY

RS 295 SW 140 Ave

LOCAL U.1-28

SE 87 RD

K44 HWY

K2 HWY

US160 HWY

SW 150 Ave

NE 30 RD

NE 130 Rd

RS 1845 NW 100 RD

US160 HWY

US160 HWY

NE 80 AVE Z.0-9.6

NW 90 RD 8.0-0.1

SW 100 Rd

US160 HWY

NW 120 Rd

Related