Delaware Bridges

872 highway bridges across 3 counties · NBI 2024 data

1.3% in poor condition
National avg: 6.8%
353
508
Good: 353 (40.5%) Fair: 508 (58.3%) Poor: 11 (1.3%)

About Delaware's Bridge Infrastructure

Delaware maintains 872 highway bridges across 3 counties, forming critical links in the state's transportation network. With an average construction year of 1977, the typical bridge in Delaware is approximately 49 years old—matching the national average. The state's oldest bridge dates back to 1839, representing over a century of service and offering a window into historic bridge engineering practices.

Currently, 1.3% of Delaware's bridges are rated in poor condition, better than the national average of 6.8%. This indicates relatively strong investment in bridge maintenance and replacement programs. A "poor" condition rating indicates significant deterioration requiring attention, though these bridges remain safe for travel at their posted limits. Federal regulations require bridge inspections at least every 24 months to ensure public safety.

Bridge conditions in Delaware reflect decades of infrastructure investment decisions shaped by geography, climate, traffic demands, and available funding. Bridges here carry 13,593 vehicles daily on average—71% higher than the national average—placing greater demands on structural maintenance. The state's 11,853,458 total daily bridge crossings underscore how essential this infrastructure is to daily commerce and commuting.

The material composition of Delaware's bridge inventory reflects regional construction practices and evolving engineering standards. The predominant construction material is steel, accounting for 42.1% of all structures. Material choice affects maintenance requirements, expected lifespan, and vulnerability to environmental factors specific to the region. Understanding these patterns helps transportation planners allocate resources effectively and prioritize infrastructure investments.

11 of 872 Delaware bridges have a rating of 4 or below. Rating 4 = advanced deterioration.

#BridgeRatingLocationBuiltDaily Traffic
1JAMES ST.
over CHRISTINA RIVER
Serious deterioration affecting structural elements. At 97 years old, this is among Delaware's oldest structures.
3
New Castle County Co. · NEWPORT BRIDGE19294,556
2MAPLE AVE
over MISPILLION RIVER
Serious deterioration affecting structural elements. Low-traffic rural crossing.
3
Kent County Co. · MILFORD197799
3CODS ROAD
over SLAUGHTER CREEK
Serious deterioration affecting structural elements. At 95 years old, this is among Delaware's oldest structures. Low-traffic rural crossing.
3
Sussex County Co. · WEST OF FOWLER BEACH193177
4GUYENCOURT RD.
over READING RR
Advanced section loss and deterioration present. At 108 years old, this is among Delaware's oldest structures.
4
New Castle County Co. · BRANDYWINE AREA1918532
5PRIVATE/PARK ROAD
over RED CLAY CREEK
Advanced section loss and deterioration present. At 111 years old, this is among Delaware's oldest structures. Low-traffic rural crossing.
4
New Castle County Co. · YORKLYN AREA191599
6SR 9
over APPOQUINIMINK RIVER
Advanced section loss and deterioration present. Built 53 years ago, approaching the end of typical service life.
4
New Castle County Co. · N/E OF ODESSA1973840
7DUPONT PKW/US13 SB
over BLACKBIRD CREEK
Advanced section loss and deterioration present. At 106 years old, this is among Delaware's oldest structures. Serves 10,619 vehicles per day.
4
New Castle County Co. · NORTH OF BLACKBIRD192010,619
8LEBANON RD/SR10 WB
over ST. JONES RIVER
Advanced section loss and deterioration present. Built 61 years ago, approaching the end of typical service life.
4
Kent County Co. · SOUTH OF DOVER19658,726
9CRAIGS MILL RD
over CRAIGS POND SPILLWAY
Advanced section loss and deterioration present. Built 53 years ago, approaching the end of typical service life.
4
Sussex County Co. · WEST OF SEAFORD1973200
10SR 54
over ASSAWOMAN BAY
Advanced section loss and deterioration present. Built 69 years ago, approaching the end of typical service life.
4
Sussex County Co. · FENWICK ISLAND19577,555

Bridges by County

New Castle County holds 60% of Delaware's bridges. Sussex County has the highest deficiency rate.

CountyBridgesConditionPoorPoor %Avg ADT
New Castle County
Largest bridge inventory in Delaware.
527
213
307
50.9%18,174
Kent County
One of Delaware's largest bridge inventories.
192
78
112
31.6%6,619
Sussex County
One of Delaware's largest bridge inventories.
153
62
89
32.0%6,568

Infrastructure Profile

Key Metrics
Average bridge age49 years
Average year built1977
Oldest bridge1839
Newest bridge2023
Avg daily traffic/bridge13,593
Total daily crossings11.9M
Rating Distribution (0–9 scale)
0–4 = Poor · 5–6 = Fair · 7–9 = Good
Construction Materials
Steel367(42.1%)
Concrete243(27.9%)
Prestressed Concrete219(25.1%)
Wood/Timber21(2.4%)
Metal (Other)13(1.5%)
Other7(0.8%)
Masonry2(0.2%)

Delaware vs. National Average

Poor Condition
1.3%
National: 6.8%✓ Better
Good Condition
40.5%
National: 44.1%✗ Worse
Average Age
49 yr
National: 49 yr✗ Worse
Avg Daily Traffic
13,593
National: 7,954✓ Better
Data Source: Federal Highway Administration, National Bridge Inventory 2024. Bridge conditions rated 0–9 per FHWA Recording and Coding Guide. "Poor" = rating ≤ 4 on deck, superstructure, substructure, or culvert.
Inspections typically occur every 24 months. Structurally deficient does not mean unsafe.
Delaware Bridges — 872 Bridges, 1.3% Poor | BridgeReport.org