US Bridges

State Route 18 over Rathbone Creek

Good

San Bernardino County, California · 08-SBD-018-50.88 · Structure no. 54 1060

Built
1978
47 years old, rebuilt 1991
Condition
Good
inspected November 2022
Type
Culvert
Concrete
Length
35 ft
2 main spans
Daily traffic
32,500
2020 count
Owner
State
State Highway Agency

About this bridge

State Route 18 over Rathbone Creek is a concrete culvert carrying State Route 18 over Rathbone Creek in San Bernardino County, California. It was built in 1978 and reconstructed in 1991, so it is 47 years old, younger than the California average of 54.8 years.

The most recent inspection reported to the Federal Highway Administration rates it in good condition with a lowest component rating of 7 out of 9. All primary components (deck, superstructure, substructure, or culvert) are rated 7 or higher. No significant problems were noted.

It carries about 32,500 vehicles a day, roughly 12% of them trucks, projected to reach 35,000 by 2040. The structure is 35 ft (10.7 m) long and 76 ft wide. If it were closed, the detour would be 1.2 mi (2 km).

Location

Open in Google Maps
CarriesState Route 18
CrossesRathbone Creek
Location08-SBD-018-50.88
RouteState Highway 18
CountySan Bernardino County
StateCalifornia
Coordinates34.24748, -116.88256
Functional classUrban Other Principal Arterial

Condition and inspection

Good

All primary components (deck, superstructure, substructure, or culvert) are rated 7 or higher. No significant problems were noted.

ComponentRatingMeaning
Channel and channel protection8 Very GoodNo problems noted.
Culvert7 GoodSome minor problems.
Last inspectionNovember 2022
Inspection intervalevery 48 months
Operating statusOpen, no restriction
ScourFoundations stable; scour above top of footing
Structural evaluation7: Better than present minimum criteria
Deck geometry7: Better than present minimum criteria
Waterway adequacy8: Equal to present desirable criteria
Approach roadway alignment6: Equal to present minimum criteria
Operating rating59.6 US tons
Inventory rating35.7 US tons

Structure

Structure typeCulvert
MaterialConcrete
DeckNot applicable
Main spans2
Design loadHS 20
Structure length35 ft (10.7 m)
Longest span12 ft (3.7 m)
Deck width76 ft (23.2 m)
Roadway width64 ft (19.5 m)
Vertical clearance over deckUnrestricted

Traffic and service

Average daily traffic32,500 (2020)
Projected traffic35,000 by 2040
Trucks12%
Lanes on structure4
Traffic directionTwo-way traffic
CarriesHighway and pedestrian
CrossesWaterway
Detour if closed1.2 mi (2 km)
TollOn a free road
National Highway SystemYes

Ownership and planned work

OwnerState Highway Agency
Maintained byState Highway Agency
Historic statusNot eligible for the National Register of Historic Places
Work proposedNone recorded
Estimated improvement cost—
NavigationNo navigation control on waterway

Frequently asked questions

When was State Route 18 over Rathbone Creek built?

It was built in 1978, making it 47 years old in 2025. It was reconstructed in 1991.

What condition is State Route 18 over Rathbone Creek in?

The National Bridge Inventory rates it in good condition. All primary components (deck, superstructure, substructure, or culvert) are rated 7 or higher. No significant problems were noted. The last reported inspection was in November 2022.

How much traffic does State Route 18 over Rathbone Creek carry?

About 32,500 vehicles per day (2020 count), of which roughly 12% are trucks.

How long is State Route 18 over Rathbone Creek?

The structure is 35 ft (10.7 m) long with a longest span of 12 ft (3.7 m) and a deck 76 ft wide.

Who owns State Route 18 over Rathbone Creek?

It is owned by the State Highway Agency.