Structure 2 0078 · Siskiyou County, CA

Interstate 5 over Willow Street

Carries Interstate 5 over Willow Street, 02-sis-005-2.09-dmr.

Overall conditionGood

Set by its lowest-rated component: Deck and Superstructure and Substructure at 7 of 9.

How ratings work
Decksets the rating7/9 · Good
Superstructuresets the rating7/9 · Good
Substructuresets the rating7/9 · Good
0 failed4 poor6 fair9 excellent

Elevation

Side view, colored by inspection rating
SEMI-TRUCK · 72 FT147 FT OVERALL25 FT0ELEVATION · LENGTHS TO SCALE
Deck 7/9Superstructure 7/9Substructure 7/9

147 ft end to end, longest span 57 ft: about 2 semi-trucks nose to tail. Lengths and the semi-truck on the deck are drawn to the same scale. Each part is colored by its latest inspection rating. The inventory records lengths but not heights or the layout of the shorter spans, so those are drawn as typical for a tee-beam bridge.

Built1960rebuilt 1987
Length147.3 ft44.9 m
Daily traffic18,000counted 2024
Last inspectedJuly 2024every 24 months

Location

StateCalifornia
CountySiskiyou
Location02-sis-005-2.09-dmr
CarriesInterstate 5
CrossesWillow Street
Coordinates41.21170, -122.27446

Physical Characteristics

MaterialConcrete Continuous
DesignTee Beam
Total Length147.3 ft (44.9 m)
Max Span57.1 ft (17.4 m)
Deck Width86.6 ft (26.4 m)
Deck Area1185.4 sq m
Main Spans3
Year Built1960 (reconstructed 1987)

Traffic

Avg Daily Traffic18,000 (2024)
Truck Traffic28%
Lanes On Bridge4
Lanes Under Bridge2

Inspection & Ownership

Last InspectionJuly 2024
Inspection FrequencyEvery 24 months
OwnerState Highway Agency
Historical SignificanceBridge is not eligible for the National Register
Scour CriticalNot applicable
Structure Number02 0078

How Bridge Ratings Work

Inspectors rate each major part of a bridge (the deck you drive on, the superstructure of beams that holds it up, and the substructure of piers and abutments beneath) on a 0–9 scale. A bridge's overall condition is its lowest of those ratings, so one deteriorated component makes the whole bridge "poor."

0Failed
1Imminent failure
2Critical
3Serious
4Poor
5Fair
6Satisfactory
7Good
8Very good
9Excellent
Good · lowest component 7–9
Fair · lowest component 5–6
Poor · lowest component 0–4

A poor rating is not a closure. It means the bridge is flagged for priority repair or replacement; bridges judged unsafe are closed or posted with weight limits. The waterway (channel) rating is reported, but it does not count toward the overall classification.

Nearby Bridges