US Bridges

I 95 NB over SR 4

Fair

New Castle County, Delaware · South Wilmington Viaduct · Structure no. 1748N059

Built
1964
61 years old, rebuilt 1980
Condition
Fair
inspected March 2023
Type
Stringer/Multi-beam or Girder
Steel
Length
2,346 ft
34 main spans
Daily traffic
63,420
2022 count
Owner
State
State Highway Agency

About this bridge

I 95 NB over SR 4 is a steel stringer/multi-beam or girder carrying I 95 NB over SR 4 in New Castle County, Delaware. It was built in 1964 and reconstructed in 1980, so it is 61 years old, older than the Delaware average of 47.3 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 63,420 vehicles a day, roughly 11% of them trucks, projected to reach 49,306 by 2042. The structure is 2,346 ft (715.1 m) long and 42 ft wide. If it were closed, the detour would be 5 mi (8 km).

Location

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CarriesI 95 NB
CrossesSR 4
LocationSouth Wilmington Viaduct
RouteInterstate 95
CountyNew Castle County
StateDelaware
Coordinates39.74139, -75.56222
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
Deck7 GoodSome minor problems.
Superstructure7 GoodSome minor problems.
Substructure6 SatisfactoryStructural elements show some minor deterioration.
Last inspectionMarch 2023
Inspection intervalevery 24 months
Operating statusOpen, no restriction
ScourBridge not over waterway
Structural evaluation6: Equal to present minimum criteria
Deck geometry6: Equal to present minimum criteria
Approach roadway alignment8: Equal to present desirable criteria
Operating rating43.5 US tons
Inventory rating33.6 US tons

Structure

Structure typeStringer/Multi-beam or Girder
MaterialSteel
DeckConcrete, cast-in-place
Main spans34
Design loadHS 20 + Mod
Structure length2,346 ft (715.1 m)
Longest span149 ft (45.4 m)
Deck width42 ft (12.9 m)
Roadway width38 ft (11.6 m)
Vertical clearance over deck17 ft (5.1 m)

Traffic and service

Average daily traffic63,420 (2022)
Projected traffic49,306 by 2042
Trucks11%
Lanes on structure2
Traffic directionOne-way traffic
CarriesOverpass structure at an interchange
CrossesHighway
Detour if closed5 mi (8 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—
NavigationNot applicable (no waterway)

Frequently asked questions

When was I 95 NB over SR 4 built?

It was built in 1964, making it 61 years old in 2025. It was reconstructed in 1980.

What condition is I 95 NB over SR 4 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 March 2023.

How much traffic does I 95 NB over SR 4 carry?

About 63,420 vehicles per day (2022 count), of which roughly 11% are trucks.

How long is I 95 NB over SR 4?

The structure is 2,346 ft (715.1 m) long with a longest span of 149 ft (45.4 m) and a deck 42 ft wide.

Who owns I 95 NB over SR 4?

It is owned by the State Highway Agency.