US Bridges

US-1 Bypass (sb) over Mill Road (T-432)

Fair

Chester County, Pennsylvania · NW Kennett Square 47C4 · Structure no. 000000000009913

Built
1965
60 years old
Condition
Fair
inspected March 2024
Type
Box Beam or Girders - Multiple
Prestressed Concrete
Length
106 ft
3 main spans
Daily traffic
15,843
2024 count
Owner
State
State Highway Agency

About this bridge

US-1 Bypass (sb) over Mill Road (T-432) is a prestressed concrete box beam or girders - multiple carrying US-1 Bypass (sb) over Mill Road (T-432) in Chester County, Pennsylvania. It was built in 1965, so it is 60 years old, older than the Pennsylvania 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 5 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 15,843 vehicles a day, roughly 3% of them trucks, projected to reach 17,809 by 2032. The structure is 106 ft (32.3 m) long and 46 ft wide. If it were closed, the detour would be 1.2 mi (2 km).

CarriesUS-1 Bypass (sb)
CrossesMill Road (T-432)
LocationNW Kennett Square 47C4
RouteU.S. Route 1
Coordinates39.85411, -75.72869
Functional classUrban Principal Arterial - Other Freeway or Expressway

Condition and inspection

Fair

The lowest-rated primary component is rated 5 or 6. Minor deterioration is present but the structure is sound.

ComponentRatingMeaning
Deck5 FairAll primary structural elements are sound but may have minor section loss, cracking, spalling or scour.
Superstructure6 SatisfactoryStructural elements show some minor deterioration.
Substructure5 FairAll primary structural elements are sound but may have minor section loss, cracking, spalling or scour.
Last inspectionMarch 2024
Inspection intervalevery 24 months
Operating statusOpen, no restriction
ScourBridge not over waterway
Structural evaluation5: Somewhat better than minimum adequacy to tolerate being left in place as is
Deck geometry7: Better than present minimum criteria
Approach roadway alignment8: Equal to present desirable criteria
Operating rating73 US tons
Inventory rating41 US tons

Structure

MaterialPrestressed Concrete
DeckConcrete, cast-in-place
Main spans3
Design loadHS 20
Structure length106 ft (32.3 m)
Longest span42 ft (12.8 m)
Deck width46 ft (13.9 m)
Roadway width40 ft (12.2 m)
Vertical clearance over deckUnrestricted

Traffic and service

Average daily traffic15,843 (2024)
Projected traffic17,809 by 2032
Trucks3%
Lanes on structure2
Traffic directionOne-way traffic
CarriesHighway
CrossesHighway
Detour if closed1.2 mi (2 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 proposedDeck rehabilitation with only incidental widening
Estimated improvement cost$271,000
NavigationNot applicable (no waterway)

Frequently asked questions

When was US-1 Bypass (sb) over Mill Road (T-432) built?

It was built in 1965, making it 60 years old in 2025.

What condition is US-1 Bypass (sb) over Mill Road (T-432) 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 2024.

How much traffic does US-1 Bypass (sb) over Mill Road (T-432) carry?

About 15,843 vehicles per day (2024 count), of which roughly 3% are trucks.

How long is US-1 Bypass (sb) over Mill Road (T-432)?

The structure is 106 ft (32.3 m) long with a longest span of 42 ft (12.8 m) and a deck 46 ft wide.

Who owns US-1 Bypass (sb) over Mill Road (T-432)?

It is owned by the State Highway Agency.