US Bridges

North State ST over Forsythe Creek

Fair

Mendocino County, California · 1.0 MI N HWY 20 E · Structure no. 10C0202

Built
1949
76 years old
Condition
Fair
inspected August 2023
Type
Stringer/Multi-beam or Girder
Steel Continuous
Length
265 ft
5 main spans
Daily traffic
20,200
2003 count
Owner
County
County Highway Agency

About this bridge

North State ST over Forsythe Creek is a steel continuous stringer/multi-beam or girder carrying North State ST over Forsythe Creek in Mendocino County, California. It was built in 1949, so it is 76 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 20,200 vehicles a day, roughly 1% of them trucks, projected to reach 31,408 by 2043. The structure is 265 ft (80.8 m) long and 32 ft wide. If it were closed, the detour would be 1.2 mi (2 km).

Location

Open in Google Maps
CarriesNorth State ST
CrossesForsythe Creek
Location1.0 MI N HWY 20 E
RouteCounty Highway 0
CountyMendocino County
StateCalifornia
Coordinates39.25414, -123.21281
Functional classRural Major Collector

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 protection8 Very GoodNo problems noted.
Last inspectionAugust 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 geometry3: Basically intolerable, requiring high priority of corrective action
Waterway adequacy9: Superior to present desirable criteria
Approach roadway alignment8: Equal to present desirable criteria
Operating rating62.2 US tons
Inventory rating37.1 US tons

Structure

Structure typeStringer/Multi-beam or Girder
MaterialSteel Continuous
DeckConcrete, cast-in-place
Main spans5
Design loadH 20
Structure length265 ft (80.8 m)
Longest span55 ft (16.8 m)
Deck width32 ft (9.7 m)
Roadway width26 ft (7.9 m)
Vertical clearance over deckUnrestricted

Traffic and service

Average daily traffic20,200 (2003)
Projected traffic31,408 by 2043
Trucks1%
Lanes on structure2
Traffic directionTwo-way traffic
CarriesHighway
CrossesWaterway
Detour if closed1.2 mi (2 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 North State ST over Forsythe Creek built?

It was built in 1949, making it 76 years old in 2025.

What condition is North State ST over Forsythe 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 August 2023.

How much traffic does North State ST over Forsythe Creek carry?

About 20,200 vehicles per day (2003 count), of which roughly 1% are trucks.

How long is North State ST over Forsythe Creek?

The structure is 265 ft (80.8 m) long with a longest span of 55 ft (16.8 m) and a deck 32 ft wide.

Who owns North State ST over Forsythe Creek?

It is owned by the County Highway Agency.