US Bridges

12th ST over Norfolk Southern

Good

New Castle County, Delaware · Wilmington · Structure no. 1814 009

Built
1977
48 years old
Condition
Good
inspected September 2023
Type
Stringer/Multi-beam or Girder
Steel Continuous
Length
288 ft
2 main spans
Daily traffic
5,790
2022 count
Owner
State
State Highway Agency

About this bridge

12th ST over Norfolk Southern is a steel continuous stringer/multi-beam or girder carrying 12th ST over Norfolk Southern in New Castle County, Delaware. It was built in 1977, so it is 48 years old, older than the Delaware average of 47.3 years.

The most recent inspection reported to the Federal Highway Administration rates it in good condition with a lowest component rating of 7 out of 9. All primary components (deck, superstructure, substructure, or culvert) are rated 7 or higher. No significant problems were noted.

It carries about 5,790 vehicles a day, roughly 7% of them trucks, projected to reach 6,338 by 2042. The structure is 288 ft (87.7 m) long and 68 ft wide. If it were closed, the detour would be 3.7 mi (6 km).

Location

Open in Google Maps
Carries12th ST
CrossesNorfolk Southern
LocationWilmington
RouteCounty Highway 9
CountyNew Castle County
StateDelaware
Coordinates39.73714, -75.52358
Functional classUrban Other Principal Arterial

Condition and inspection

Good

All primary components (deck, superstructure, substructure, or culvert) are rated 7 or higher. No significant problems were noted.

ComponentRatingMeaning
Deck7 GoodSome minor problems.
Superstructure7 GoodSome minor problems.
Substructure7 GoodSome minor problems.
Last inspectionSeptember 2023
Inspection intervalevery 24 months
Operating statusOpen, no restriction
ScourBridge not over waterway
Structural evaluation6: Equal to present minimum criteria
Deck geometry4: Meets minimum tolerable limits to be left in place as is
Approach roadway alignment8: Equal to present desirable criteria
Operating rating38.3 US tons
Inventory rating29.3 US tons

Structure

Structure typeStringer/Multi-beam or Girder
MaterialSteel Continuous
DeckConcrete, cast-in-place
Main spans2 (+1 approach)
Design loadHS 20
Structure length288 ft (87.7 m)
Longest span115 ft (35.1 m)
Deck width68 ft (20.7 m)
Roadway width52 ft (15.8 m)
Vertical clearance over deckUnrestricted

Traffic and service

Average daily traffic5,790 (2022)
Projected traffic6,338 by 2042
Trucks7%
Lanes on structure4
Traffic directionTwo-way traffic
CarriesHighway and pedestrian
CrossesRailroad
Detour if closed3.7 mi (6 km)
TollOn a free road
National Highway SystemYes

Ownership and planned work

OwnerState Highway Agency
Maintained byState Highway Agency
Historic statusNot eligible for the National Register of Historic Places
Work proposedRehabilitation because of general structure deterioration or inadequate strength
Estimated improvement cost$1,000
NavigationNot applicable (no waterway)

Frequently asked questions

When was 12th ST over Norfolk Southern built?

It was built in 1977, making it 48 years old in 2025.

What condition is 12th ST over Norfolk Southern in?

The National Bridge Inventory rates it in good condition. All primary components (deck, superstructure, substructure, or culvert) are rated 7 or higher. No significant problems were noted. The last reported inspection was in September 2023.

How much traffic does 12th ST over Norfolk Southern carry?

About 5,790 vehicles per day (2022 count), of which roughly 7% are trucks.

How long is 12th ST over Norfolk Southern?

The structure is 288 ft (87.7 m) long with a longest span of 115 ft (35.1 m) and a deck 68 ft wide.

Who owns 12th ST over Norfolk Southern?

It is owned by the State Highway Agency.