Home › California › Butte County › First St over Hamilton Slough

First St over Hamilton Slough

Butte County, California · rated Fair in the 2025 National Bridge Inventory

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

First St over Hamilton Slough in Butte County, California, is rated in fair condition in the 2025 National Bridge Inventory (as of August 20, 2026).
Its lowest-rated component is the superstructure, rated 5 (fair condition) on the 0-9 scale.
It was built in 1938, making it 87 years old at the 2025 inventory.
It carries about 80 vehicles a day (traffic count year 2019).
Its listed owner is a city or municipal highway agency.
It is one of 278 of the 440 inventoried bridges in Butte County rated fair (63.2%); 24 (5.5%) are rated poor.
A fair rating means the lowest-rated major component scores 5 or 6 on FHWA's 0-9 scale: some deterioration or minor section loss, but the structure is sound. It is the middle class, not a warning.

Component ratings

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

Bridge	Built	Vehicles/day	Condition
Skyway over State Route 99	1965	37,400	Good
State Route 99 over Dry Channel	1953	32,600	Good
State Route 99 over Scrub Creek	1952	28,250	Good
State Route 99 over Nance Canyon	1952	28,250	Good
Cohasset Hwy over State Route 99	1966	27,008	Good
State Route 99 SB over Little Chico Creek	1965	24,750	Fair