US Bridges

State Route 253 over U.S. 101 (@ Pm R21.59)

Fair

Mendocino County, California · 01-MEN-253-17.16 · Structure no. 10 0186

Built
1964
61 years old
Condition
Fair
inspected May 2023
Type
Tee Beam
Concrete Continuous
Length
225 ft
4 main spans
Daily traffic
2,700
2011 count
Owner
State
State Highway Agency

About this bridge

State Route 253 over U.S. 101 (@ Pm R21.59) is a concrete continuous tee beam carrying State Route 253 over U.S. 101 (@ Pm R21.59) in Mendocino County, California. It was built in 1964, so it is 61 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 2,700 vehicles a day, roughly 8% of them trucks, projected to reach 3,700 by 2043. The structure is 225 ft (68.6 m) long and 35 ft wide. If it were closed, the detour would be 5 mi (8 km).

Location

Open in Google Maps
CarriesState Route 253
CrossesU.S. 101 (@ Pm R21.59)
Location01-MEN-253-17.16
RouteState Highway 253
CountyMendocino County
StateCalifornia
Coordinates39.10923, -123.19557
Functional classUrban Minor Arterial

Condition and inspection

Fair

The lowest-rated primary component is rated 5 or 6. Minor deterioration is present but the structure is sound.

ComponentRatingMeaning
Deck5 FairAll primary structural elements are sound but may have minor section loss, cracking, spalling or scour.
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.
Last inspectionMay 2023
Inspection intervalevery 24 months
Operating statusOpen, no restriction
ScourBridge not over waterway
Structural evaluation5: Somewhat better than minimum adequacy to tolerate being left in place as is
Deck geometry4: Meets minimum tolerable limits to be left in place as is
Approach roadway alignment6: Equal to present minimum criteria
Operating rating44.6 US tons
Inventory rating32.5 US tons

Structure

Structure typeTee Beam
MaterialConcrete Continuous
DeckConcrete, cast-in-place
Main spans4
Design loadHS 20 + Mod
Structure length225 ft (68.6 m)
Longest span65 ft (19.8 m)
Deck width35 ft (10.6 m)
Roadway width33 ft (10 m)
Vertical clearance over deckUnrestricted

Traffic and service

Average daily traffic2,700 (2011)
Projected traffic3,700 by 2043
Trucks8%
Lanes on structure2
Traffic directionTwo-way traffic
CarriesHighway
CrossesHighway
Detour if closed5 mi (8 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—
NavigationNot applicable (no waterway)

Frequently asked questions

When was State Route 253 over U.S. 101 (@ Pm R21.59) built?

It was built in 1964, making it 61 years old in 2025.

What condition is State Route 253 over U.S. 101 (@ Pm R21.59) 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 May 2023.

How much traffic does State Route 253 over U.S. 101 (@ Pm R21.59) carry?

About 2,700 vehicles per day (2011 count), of which roughly 8% are trucks.

How long is State Route 253 over U.S. 101 (@ Pm R21.59)?

The structure is 225 ft (68.6 m) long with a longest span of 65 ft (19.8 m) and a deck 35 ft wide.

Who owns State Route 253 over U.S. 101 (@ Pm R21.59)?

It is owned by the State Highway Agency.