County profile · official public datasets

Sweetwater County, WY

191 public highway bridges tracked in the FHWA National Bridge Inventory: 28.8% rated Good, 62.8% Fair, 8.4% Poor.

191
Public bridges: 28.8%
Good condition: 8.4%
Poor condition

The verdict

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

Sweetwater County posts a higher-than-median Poor-condition share among rated counties in the state across mid-size county bridge inventory.

15th
of 23 on Poor share: 8.4%
Poor-condition share: 191
public highway bridges: 1976
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.

Sweetwater County Bridge Snapshot

According to the Federal Highway Administration's 2024 National Bridge Inventory, Sweetwater County ranks #15 of 23 Wyoming counties with at least 5 public highway bridges on Poor-condition share (lower share ranks better; currently 8.4%). Sweetwater County, Wyoming contains 191 public highway bridges. Roughly 28.8% are rated “Good,” 62.8% “Fair,” and 8.4% “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

191

Public highway bridges in Sweetwater County

Good condition

28.8%

55 of 191 rated 7-9

Fair condition

62.8%

120 of 191 rated 5-6

Poor condition

8.4%

16 of 191 rated 4 or below

In-state Poor-share rank

#15 of 23

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

Condition distribution

Share of 191 NBI-tracked bridges by lowest applicable component rating.

Good

28.8% (55)

Fair

62.8% (120)

Poor

8.4% (16)

Sweetwater County's Poor-condition bridges carry 65,696 vehicle crossings a day

That is 6.6% of the county's reported daily bridge traffic on 8.4% of its bridges: Poor-condition structures carry less traffic than their share of the inventory. Each Poor bridge averages 4,106 crossings a day against 4,811 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 191 of 191 bridges in this county that report an average daily traffic count. Source: FHWA National Bridge Inventory, 2024 release.

58.1% of Sweetwater County's bridges have passed the 50-year mark

111 of the 191 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 28.8% 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 15.1% of the county's Poor-condition bridge traffic

WYO 530 SBL over UPRR / I-80 Bus, built 1978, carries 9,912 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 16-bridge count understates how much of the daily burden sits on a single crossing.

Share is of the 65,696 daily crossings on Poor-rated bridges that report a traffic count. Source: FHWA National Bridge Inventory, 2024 release.

1920s

1
1940s

8
1950s

15
1960s

86
1970s

9
1980s

19
1990s

12
2000s

28
2010s

10
2020s

3

What this shows Construction peaked in the 1960s, when 86 of the county's bridges still in the inventory were built, which is 45% of those with a recorded year. That cohort is now 55 to 64 years old in the 2024 inventory. Its average build year (1976) matches the Wyoming average (1976).

How Sweetwater County compares with Wyoming's closest counties by inventory size

The 5 Wyoming counties nearest Sweetwater County in number of bridges, with their condition splits. Its 8.4% Poor share is the 6th-lowest of these 6. Its average build year of 1976 against a peer-group mean of 1975 is in line with the group.

Showing the 5 closest of 22 Wyoming counties eligible for comparison.

Bridge inventory size and condition shares for Sweetwater County and the 5 Wyoming counties closest to it in inventory size
County	Bridges	Good	Fair	Poor	Avg. built
Carbon County	206	38.8%	54.4%	6.8%	1973
Johnson County	204	26.5%	70.6%	2.9%	1970
Sweetwater County (this page)	191	28.8%	62.8%	8.4%	1976
Park County	187	37.4%	58.3%	4.3%	1979
Fremont County	177	47.5%	46.3%	6.2%	1981
Crook County	176	30.7%	67.6%	1.7%	1974

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

Similar inventory size

Nearest county inventories outside WY (191 bridges here).

Jay County, IN · 191 bridges
Ripley County, IN · 191 bridges
Atchison County, MO · 191 bridges
Pawnee County, NE · 191 bridges

Similar average build year

Nearest mean year-built outside WY (1976 here).

Marion County, IN · avg 1976 · 958 bridges
Mohave County, AZ · avg 1976 · 641 bridges
Comanche County, OK · avg 1976 · 593 bridges
Prince George's County, MD · avg 1976 · 576 bridges

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

All 191 Good 55 Fair 120 Poor 16

Fair-condition bridges (120)

Sort:

Sweetwater County Bridge Snapshot

Condition distribution

Sweetwater County's Poor-condition bridges carry 65,696 vehicle crossings a day

58.1% of Sweetwater County's bridges have passed the 50-year mark

One structure carries 15.1% of the county's Poor-condition bridge traffic

How Sweetwater County compares with Wyoming's closest counties by inventory size

Nationwide counties with similar inventory size or average build year

Similar inventory size

Similar average build year

Fair-condition bridges (120)

WYO 530 NBL

US 30

I-80 EBL

I-80 EBL On Ramp

Sw Cnty Rd 23S

I-80 WBL

WYO 374

US 30

I-80 WBL

Sw Cnty Rd 58

Interchange Road

US 191

Scotts Bottom Road

I-80 EBL

I-80 WBL

Sw Cnty Rd 8

I-80 EBL

Connecticut Ave

I-80 WBL

3318: SHELL CREEK

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