US Bridges

Road 51 over Glenn-Colusa Canal

Fair

Glenn County, California · West of Newmark Ave · Structure no. 11C0055

Built
1948
77 years old
Condition
Fair
inspected January 2025
Type
Slab
Concrete Continuous
Length
92 ft
3 main spans
Daily traffic
140
2013 count
Owner
County
County Highway Agency

About this bridge

Road 51 over Glenn-Colusa Canal is a concrete continuous slab carrying Road 51 over Glenn-Colusa Canal in Glenn County, California. It was built in 1948, so it is 77 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 140 vehicles a day, roughly 5% of them trucks, projected to reach 162 by 2043. The structure is 92 ft (28 m) long and 25 ft wide. If it were closed, the detour would be 123.7 mi (199 km).

Location

Open in Google Maps
CarriesRoad 51
CrossesGlenn-Colusa Canal
LocationWest of Newmark Ave
RouteCounty Highway 0
CountyGlenn County
StateCalifornia
Coordinates39.51691, -122.18902
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
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.
Channel and channel protection7 GoodSome minor problems.
Last inspectionJanuary 2025
Inspection intervalevery 24 months
Operating statusOpen, no restriction
ScourFoundations stable; scour within limits of footing or piles
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 adequacy9: Superior to present desirable criteria
Approach roadway alignment6: Equal to present minimum criteria
Operating rating36.4 US tons
Inventory rating22.2 US tons

Structure

Structure typeSlab
MaterialConcrete Continuous
DeckConcrete, cast-in-place
Main spans3
Design loadHS 15
Structure length92 ft (28 m)
Longest span30 ft (9.1 m)
Deck width25 ft (7.6 m)
Roadway width20 ft (6 m)
Vertical clearance over deckUnrestricted

Traffic and service

Average daily traffic140 (2013)
Projected traffic162 by 2043
Trucks5%
Lanes on structure2
Traffic directionTwo-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 Road 51 over Glenn-Colusa Canal built?

It was built in 1948, making it 77 years old in 2025.

What condition is Road 51 over Glenn-Colusa Canal 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 January 2025.

How much traffic does Road 51 over Glenn-Colusa Canal carry?

About 140 vehicles per day (2013 count), of which roughly 5% are trucks.

How long is Road 51 over Glenn-Colusa Canal?

The structure is 92 ft (28 m) long with a longest span of 30 ft (9.1 m) and a deck 25 ft wide.

Who owns Road 51 over Glenn-Colusa Canal?

It is owned by the County Highway Agency.