US Bridges

Perimeter Road over Union Creek

Fair

Solano County, California · 1.2 Miles West of Carson · Structure no. AFCAXDAT00002

Built
1956
69 years old
Condition
Fair
inspected October 2023
Type
Stringer/Multi-beam or Girder
Steel
Length
101 ft
2 main spans
Daily traffic
75
2015 count
Owner
Federal
Air Force

About this bridge

Perimeter Road over Union Creek is a steel stringer/multi-beam or girder carrying Perimeter Road over Union Creek in Solano County, California. It was built in 1956, so it is 69 years old, older than the California average of 54.8 years.

The most recent inspection reported to the Federal Highway Administration rates it in fair condition with a lowest component rating of 6 out of 9. The lowest-rated primary component is rated 5 or 6. Minor deterioration is present but the structure is sound.

It carries about 75 vehicles a day, projected to reach 90 by 2035. The structure is 101 ft (30.9 m) long and 22 ft wide. If it were closed, the detour would be 5 mi (8 km).

Location

Open in Google Maps
CarriesPerimeter Road
CrossesUnion Creek
Location1.2 Miles West of Carson
CountySolano County
StateCalifornia
Coordinates38.24458, -121.94984
Functional classRural Local

Condition and inspection

Fair

The lowest-rated primary component is rated 5 or 6. Minor deterioration is present but the structure is sound.

ComponentRatingMeaning
Deck6 SatisfactoryStructural elements show some minor deterioration.
Superstructure6 SatisfactoryStructural elements show some minor deterioration.
Substructure7 GoodSome minor problems.
Channel and channel protection6 SatisfactoryStructural elements show some minor deterioration.
Last inspectionOctober 2023
Inspection intervalevery 24 months
Operating statusOpen, no restriction
ScourScour critical; foundations unstable for calculated scour conditions
Structural evaluation6: Equal to present minimum criteria
Deck geometry5: Somewhat better than minimum adequacy to tolerate being left in place as is
Waterway adequacy8: Equal to present desirable criteria
Approach roadway alignment8: Equal to present desirable criteria
Operating rating53 US tons
Inventory rating31 US tons

Structure

Structure typeStringer/Multi-beam or Girder
MaterialSteel
DeckWood or timber
Main spans2
Design loadUnknown
Structure length101 ft (30.9 m)
Longest span48 ft (14.6 m)
Deck width22 ft (6.7 m)
Roadway width20 ft (6.2 m)
Vertical clearance over deckUnrestricted

Traffic and service

Average daily traffic75 (2015)
Projected traffic90 by 2035
Trucks—
Lanes on structure2
Traffic directionTwo-way traffic
CarriesHighway
CrossesWaterway
Detour if closed5 mi (8 km)
TollOn a free road
National Highway SystemNo

Ownership and planned work

OwnerAir Force
Maintained byAir Force
Historic statusNot eligible for the National Register of Historic Places
Work proposedNone recorded
Estimated improvement cost$280,000
NavigationNot applicable (no waterway)

Frequently asked questions

When was Perimeter Road over Union Creek built?

It was built in 1956, making it 69 years old in 2025.

What condition is Perimeter Road over Union Creek in?

The National Bridge Inventory rates it in fair condition. The lowest-rated primary component is rated 5 or 6. Minor deterioration is present but the structure is sound. The last reported inspection was in October 2023.

How much traffic does Perimeter Road over Union Creek carry?

About 75 vehicles per day (2015 count).

How long is Perimeter Road over Union Creek?

The structure is 101 ft (30.9 m) long with a longest span of 48 ft (14.6 m) and a deck 22 ft wide.

Who owns Perimeter Road over Union Creek?

It is owned by the Air Force.