US Bridges

Old Mattole RD over Mcnutt Creek

Fair

Humboldt County, California · 0.49 MI N of Mattole RD · Structure no. 04C0069

Built
1926
99 years old
Condition
Fair
inspected March 2024
Type
Truss - Thru
Steel
Length
84 ft
1 main span
Daily traffic
100
1979 count
Owner
County
County Highway Agency

About this bridge

Old Mattole RD over Mcnutt Creek is a steel truss - thru carrying Old Mattole RD over Mcnutt Creek in Humboldt County, California. It was built in 1926, so it is 99 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 5 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 100 vehicles a day, projected to reach 55 by 2042. The structure is 84 ft (25.6 m) long and 14 ft wide. If it were closed, the detour would be 123.7 mi (199 km).

Location

Open in Google Maps
CarriesOld Mattole RD
CrossesMcnutt Creek
Location0.49 MI N of Mattole RD
RouteCounty Highway 0
CountyHumboldt County
StateCalifornia
Coordinates40.35255, -124.33275
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
Deck7 GoodSome minor problems.
Superstructure5 FairAll primary structural elements are sound but may have minor section loss, cracking, spalling or scour.
Substructure7 GoodSome minor problems.
Channel and channel protection7 GoodSome minor problems.
Last inspectionMarch 2024
Inspection intervalevery 24 months
Operating statusOpen, no restriction
ScourFoundations stable; scour above top of footing
Structural evaluation5: Somewhat better than minimum adequacy to tolerate being left in place as is
Deck geometry5: Somewhat better than minimum adequacy to tolerate being left in place as is
Waterway adequacy8: Equal to present desirable criteria
Approach roadway alignment3: Basically intolerable, requiring high priority of corrective action
Operating rating32.2 US tons
Inventory rating19.3 US tons

Structure

Structure typeTruss - Thru
MaterialSteel
DeckWood or timber
Main spans1
Design loadUnknown
Structure length84 ft (25.6 m)
Longest span84 ft (25.6 m)
Deck width14 ft (4.4 m)
Roadway width13 ft (4 m)
Vertical clearance over deckUnrestricted

Traffic and service

Average daily traffic100 (1979)
Projected traffic55 by 2042
Trucks—
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—
NavigationNo navigation control on waterway

Frequently asked questions

When was Old Mattole RD over Mcnutt Creek built?

It was built in 1926, making it 99 years old in 2025.

What condition is Old Mattole RD over Mcnutt 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 March 2024.

How much traffic does Old Mattole RD over Mcnutt Creek carry?

About 100 vehicles per day (1979 count).

How long is Old Mattole RD over Mcnutt Creek?

The structure is 84 ft (25.6 m) long with a longest span of 84 ft (25.6 m) and a deck 14 ft wide.

Who owns Old Mattole RD over Mcnutt Creek?

It is owned by the County Highway Agency.