US Bridges

Hamilton Road over First Gulch

Fair

Del Norte County, California · 3.1 Miles East of US 101 · Structure no. 01P0014

Built
1950
75 years old
Condition
Fair
inspected June 2024
Type
Stringer/Multi-beam or Girder
Steel
Length
50 ft
1 main span
Daily traffic
10
2004 count
Owner
State
State Park, Forest, or Reservation Agency

About this bridge

Hamilton Road over First Gulch is a steel stringer/multi-beam or girder carrying Hamilton Road over First Gulch in Del Norte County, California. It was built in 1950, so it is 75 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 10 vehicles a day, roughly 10% of them trucks, projected to reach 21 by 2044. The structure is 50 ft (15.3 m) long and 20 ft wide. If it were closed, the detour would be 123.7 mi (199 km).

Location

Open in Google Maps
CarriesHamilton Road
CrossesFirst Gulch
Location3.1 Miles East of US 101
RouteState Lands Road 0
CountyDel Norte County
StateCalifornia
Coordinates41.73156, -124.09034
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.
Substructure5 FairAll primary structural elements are sound but may have minor section loss, cracking, spalling or scour.
Channel and channel protection6 SatisfactoryStructural elements show some minor deterioration.
Last inspectionJune 2024
Inspection intervalevery 24 months
Operating statusOpen, no restriction
ScourScour critical; foundations unstable for calculated scour conditions
Structural evaluation5: Somewhat better than minimum adequacy to tolerate being left in place as is
Deck geometry3: Basically intolerable, requiring high priority of corrective action
Waterway adequacy6: Equal to present minimum criteria
Approach roadway alignment8: Equal to present desirable criteria
Operating rating57.5 US tons
Inventory rating34.6 US tons

Structure

Structure typeStringer/Multi-beam or Girder
MaterialSteel
DeckWood or timber
Main spans1
Design loadUnknown
Structure length50 ft (15.3 m)
Longest span47 ft (14.4 m)
Deck width20 ft (6.2 m)
Roadway width17 ft (5.3 m)
Vertical clearance over deckUnrestricted

Traffic and service

Average daily traffic10 (2004)
Projected traffic21 by 2044
Trucks10%
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

OwnerState Park, Forest, or Reservation Agency
Maintained byState Park, Forest, or Reservation Agency
Historic statusHistorical significance not determinable at this time
Work proposedNone recorded
Estimated improvement cost—
NavigationNot applicable (no waterway)

Frequently asked questions

When was Hamilton Road over First Gulch built?

It was built in 1950, making it 75 years old in 2025.

What condition is Hamilton Road over First Gulch 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 June 2024.

How much traffic does Hamilton Road over First Gulch carry?

About 10 vehicles per day (2004 count), of which roughly 10% are trucks.

How long is Hamilton Road over First Gulch?

The structure is 50 ft (15.3 m) long with a longest span of 47 ft (14.4 m) and a deck 20 ft wide.

Who owns Hamilton Road over First Gulch?

It is owned by the State Park, Forest, or Reservation Agency.