US 20 over South Fork Casper Creek

Natrona County, Wyoming · rated Good in the 2025 National Bridge Inventory

United States Bridge Conditions2025 National Bridge Inventory, FHWACompiled August 20, 2026

• US 20 over South Fork Casper Creek in Natrona County, Wyoming, is rated in good condition in the 2025 National Bridge Inventory (as of August 20, 2026).
• Its lowest-rated component is the deck, rated 7 (good condition) on the 0-9 scale.
• It was built in 1976, making it 49 years old at the 2025 inventory.
• It carries about 2,931 vehicles a day (traffic count year 2024).
• Its listed owner is the state highway agency.
• It is one of 45 of the 135 inventoried bridges in Natrona County rated good (33.3%); 5 (3.7%) are rated poor.
• A good rating means every major component - deck, superstructure, substructure, or culvert - is rated 7 or higher on FHWA's 0-9 scale: no more than minor problems.

View this bridge on a map → (42.95891, -106.65594)

Component ratings

Bridge details

Source: FHWA National Bridge Inventory, 2025 data as reported by the Wyoming department of transportation.

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Background: how bridge ratings work · what "poor" and "structurally deficient" actually mean · how often bridges are inspected.