US Bridges

I0310 over S.P. R.R. & LA 631

Fair

St. Charles Parish, Louisiana · .5 MI North of US 90 · Structure no. 024504503803756

Built
1986
39 years old
Condition
Fair
inspected October 2023
Type
Stringer/Multi-beam or Girder
Prestressed Concrete
Length
1,319 ft
17 main spans
Daily traffic
29,468
2021 count
Owner
State
State Highway Agency

About this bridge

I0310 over S.P. R.R. & LA 631 is a prestressed concrete stringer/multi-beam or girder carrying I0310 over S.P. R.R. & LA 631 in St. Charles Parish, Louisiana. It was built in 1986, so it is 39 years old, younger than the Louisiana average of 43 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 29,468 vehicles a day, roughly 25% of them trucks, projected to reach 32,414 by 2041. The structure is 1,319 ft (402 m) long and 28 ft wide.

Location

Open in Google Maps
CarriesI0310
CrossesS.P. R.R. & LA 631
Location.5 MI North of US 90
RouteInterstate 310
CountySt. Charles Parish
StateLouisiana
Coordinates29.89659, -90.3964
Functional classUrban Principal Arterial - Interstate

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.
Substructure8 Very GoodNo problems noted.
Last inspectionOctober 2023
Inspection intervalevery 24 months
Operating statusOpen, no restriction
ScourBridge not over waterway
Structural evaluation6: Equal to present minimum criteria
Deck geometry7: Better than present minimum criteria
Approach roadway alignment8: Equal to present desirable criteria
Operating rating64 US tons
Inventory rating38 US tons

Structure

Structure typeStringer/Multi-beam or Girder
MaterialPrestressed Concrete
DeckConcrete, cast-in-place
Main spans17 (+3 approach)
Design loadHS 20
Structure length1,319 ft (402 m)
Longest span112 ft (34.1 m)
Deck width28 ft (8.5 m)
Roadway width25 ft (7.6 m)
Vertical clearance over deckUnrestricted

Traffic and service

Average daily traffic29,468 (2021)
Projected traffic32,414 by 2041
Trucks25%
Lanes on structure1
Traffic directionOne-way traffic
CarriesHighway
CrossesHighway and railroad
Detour if closed—
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—
NavigationNot applicable (no waterway)

Frequently asked questions

When was I0310 over S.P. R.R. & LA 631 built?

It was built in 1986, making it 39 years old in 2025.

What condition is I0310 over S.P. R.R. & LA 631 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 October 2023.

How much traffic does I0310 over S.P. R.R. & LA 631 carry?

About 29,468 vehicles per day (2021 count), of which roughly 25% are trucks.

How long is I0310 over S.P. R.R. & LA 631?

The structure is 1,319 ft (402 m) long with a longest span of 112 ft (34.1 m) and a deck 28 ft wide.

Who owns I0310 over S.P. R.R. & LA 631?

It is owned by the State Highway Agency.