US Bridges

State Route 1 over Eskoot Creek

Good

Marin County, California · 04-MRN-001-12.37 · Structure no. 27 0077

Built
1957
68 years old
Condition
Good
inspected May 2024
Type
Slab
Concrete
Length
25 ft
1 main span
Daily traffic
4,100
2020 count
Owner
State
State Highway Agency

About this bridge

State Route 1 over Eskoot Creek is a concrete slab carrying State Route 1 over Eskoot Creek in Marin County, California. It was built in 1957, so it is 68 years old, older 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 4,100 vehicles a day, projected to reach 5,430 by 2042. The structure is 25 ft (7.6 m) long and 42 ft wide. If it were closed, the detour would be 28 mi (45 km).

Location

Open in Google Maps
CarriesState Route 1
CrossesEskoot Creek
Location04-MRN-001-12.37
RouteState Highway 1
CountyMarin County
StateCalifornia
Coordinates37.89843, -122.63751
Functional classRural Minor Arterial

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 protection8 Very GoodNo problems noted.
Last inspectionMay 2024
Inspection intervalevery 24 months
Operating statusOpen, no restriction
ScourFoundations stable; scour above top of footing
Structural evaluation7: Better than present minimum criteria
Deck geometry4: Meets minimum tolerable limits to be left in place as is
Waterway adequacy8: Equal to present desirable criteria
Approach roadway alignment4: Meets minimum tolerable limits to be left in place as is
Operating rating55.3 US tons
Inventory rating33.2 US tons

Structure

Structure typeSlab
MaterialConcrete
DeckConcrete, cast-in-place
Main spans1
Design loadHS 20
Structure length25 ft (7.6 m)
Longest span20 ft (6.1 m)
Deck width42 ft (12.9 m)
Roadway width30 ft (9.1 m)
Vertical clearance over deckUnrestricted

Traffic and service

Average daily traffic4,100 (2020)
Projected traffic5,430 by 2042
Trucks0%
Lanes on structure2
Traffic directionTwo-way traffic
CarriesHighway and pedestrian
CrossesWaterway
Detour if closed28 mi (45 km)
TollOn a free road
National Highway SystemNo

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 1 over Eskoot Creek built?

It was built in 1957, making it 68 years old in 2025.

What condition is State Route 1 over Eskoot 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 May 2024.

How much traffic does State Route 1 over Eskoot Creek carry?

About 4,100 vehicles per day (2020 count).

How long is State Route 1 over Eskoot Creek?

The structure is 25 ft (7.6 m) long with a longest span of 20 ft (6.1 m) and a deck 42 ft wide.

Who owns State Route 1 over Eskoot Creek?

It is owned by the State Highway Agency.