US Bridges

State Route 99 NB over Webber Canal

Fair

Merced County, California · 10-MER-099-19.49 · Structure no. 39 0018R

Built
1947
78 years old, rebuilt 1973
Condition
Fair
inspected December 2023
Type
Slab
Concrete Continuous
Length
66 ft
3 main spans
Daily traffic
28,000
2009 count
Owner
State
State Highway Agency

About this bridge

State Route 99 NB over Webber Canal is a concrete continuous slab carrying State Route 99 NB over Webber Canal in Merced County, California. It was built in 1947 and reconstructed in 1973, so it is 78 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 28,000 vehicles a day, roughly 20% of them trucks, projected to reach 40,546 by 2041. The structure is 66 ft (20.1 m) long and 36 ft wide. If it were closed, the detour would be 3.1 mi (5 km).

Location

Open in Google Maps
CarriesState Route 99 NB
CrossesWebber Canal
Location10-MER-099-19.49
RouteState Highway 99
CountyMerced County
StateCalifornia
Coordinates37.32766, -120.55897
Functional classUrban Other Principal 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
Deck7 GoodSome minor problems.
Superstructure7 GoodSome minor problems.
Substructure6 SatisfactoryStructural elements show some minor deterioration.
Channel and channel protection8 Very GoodNo problems noted.
Last inspectionDecember 2023
Inspection intervalevery 24 months
Operating statusOpen, no restriction
ScourFoundations stable; scour within limits of footing or piles
Structural evaluation6: Equal to present minimum criteria
Deck geometry5: Somewhat better than minimum adequacy to tolerate being left in place as is
Waterway adequacy6: Equal to present minimum criteria
Approach roadway alignment8: Equal to present desirable criteria
Operating rating55 US tons
Inventory rating33.2 US tons

Structure

Structure typeSlab
MaterialConcrete Continuous
DeckConcrete, cast-in-place
Main spans3
Design loadUnknown
Structure length66 ft (20.1 m)
Longest span25 ft (7.6 m)
Deck width36 ft (10.9 m)
Roadway width35 ft (10.7 m)
Vertical clearance over deckUnrestricted

Traffic and service

Average daily traffic28,000 (2009)
Projected traffic40,546 by 2041
Trucks20%
Lanes on structure2
Traffic directionOne-way traffic
CarriesHighway
CrossesWaterway
Detour if closed3.1 mi (5 km)
TollOn a free road
National Highway SystemYes
Strategic Highway NetworkInterstate STRAHNET route

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 99 NB over Webber Canal built?

It was built in 1947, making it 78 years old in 2025. It was reconstructed in 1973.

What condition is State Route 99 NB over Webber 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 December 2023.

How much traffic does State Route 99 NB over Webber Canal carry?

About 28,000 vehicles per day (2009 count), of which roughly 20% are trucks.

How long is State Route 99 NB over Webber Canal?

The structure is 66 ft (20.1 m) long with a longest span of 25 ft (7.6 m) and a deck 36 ft wide.

Who owns State Route 99 NB over Webber Canal?

It is owned by the State Highway Agency.