US Bridges

Chimney Rock Road over Franklin Creek

Good

San Luis Obispo County, California · 1.8 MI NE of Madrona Road · Structure no. 49C0492

Built
2023
2 years old
Condition
Good
inspected September 2023
Type
Truss - Thru
Steel
Length
171 ft
1 main span
Daily traffic
100
2023 count
Owner
County
County Highway Agency

About this bridge

Chimney Rock Road over Franklin Creek is a steel truss - thru carrying Chimney Rock Road over Franklin Creek in San Luis Obispo County, California. It was built in 2023, so it is 2 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 100 vehicles a day, roughly 3% of them trucks, projected to reach 150 by 2041. The structure is 171 ft (52.1 m) long and 20 ft wide. If it were closed, the detour would be 123.7 mi (199 km).

Location

Open in Google Maps
CarriesChimney Rock Road
CrossesFranklin Creek
Location1.8 MI NE of Madrona Road
RouteCounty Highway 0
CountySan Luis Obispo County
StateCalifornia
Coordinates35.68206, -120.94953
Functional classRural Local

Condition and inspection

Good

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

ComponentRatingMeaning
Deck7 GoodSome minor problems.
Superstructure7 GoodSome minor problems.
Substructure7 GoodSome minor problems.
Channel and channel protection5 FairAll primary structural elements are sound but may have minor section loss, cracking, spalling or scour.
Last inspectionSeptember 2023
Inspection intervalevery 24 months
Operating statusOpen, no restriction
ScourFoundations stable; scour within limits of footing or piles
Structural evaluation7: Better than present minimum criteria
Deck geometry5: Somewhat better than minimum adequacy to tolerate being left in place as is
Waterway adequacy5: Somewhat better than minimum adequacy to tolerate being left in place as is
Approach roadway alignment6: Equal to present minimum criteria
Operating rating59.5 US tons
Inventory rating35.7 US tons

Structure

Structure typeTruss - Thru
MaterialSteel
DeckCorrugated steel
Main spans1
Design loadHL 93
Structure length171 ft (52.1 m)
Longest span170 ft (51.7 m)
Deck width20 ft (6.1 m)
Roadway width14 ft (4.2 m)
Vertical clearance over deckUnrestricted

Traffic and service

Average daily traffic100 (2023)
Projected traffic150 by 2041
Trucks3%
Lanes on structure1
Traffic directionOne-lane bridge for two-way traffic
CarriesHighway
CrossesWaterway
Detour if closed123.7 mi (199 km)
TollOn a free road
National Highway SystemNo

Ownership and planned work

OwnerCounty Highway Agency
Maintained byCounty Highway Agency
Historic statusNot eligible for the National Register of Historic Places
Work proposedNone recorded
Estimated improvement cost—
NavigationNot applicable (no waterway)

Frequently asked questions

When was Chimney Rock Road over Franklin Creek built?

It was built in 2023, making it 2 years old in 2025.

What condition is Chimney Rock Road over Franklin 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 September 2023.

How much traffic does Chimney Rock Road over Franklin Creek carry?

About 100 vehicles per day (2023 count), of which roughly 3% are trucks.

How long is Chimney Rock Road over Franklin Creek?

The structure is 171 ft (52.1 m) long with a longest span of 170 ft (51.7 m) and a deck 20 ft wide.

Who owns Chimney Rock Road over Franklin Creek?

It is owned by the County Highway Agency.