US Bridges

EB US 30 over Silver Ck & UP RR

Fair

Clinton County, Iowa · 0.7 Mi. E of W JCT US 61 · Structure no. 000000000602830

Built
1970
55 years old, rebuilt 1975
Condition
Fair
inspected October 2022
Type
Stringer/Multi-beam or Girder
Prestressed Concrete
Length
425 ft
6 main spans
Daily traffic
8,550
2022 count
Owner
State
State Highway Agency

About this bridge

EB US 30 over Silver Ck & UP RR is a prestressed concrete stringer/multi-beam or girder carrying EB US 30 over Silver Ck & UP RR in Clinton County, Iowa. It was built in 1970 and reconstructed in 1975, so it is 55 years old, older than the Iowa average of 45.5 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 8,550 vehicles a day, roughly 15% of them trucks, projected to reach 8,550 by 2042. The structure is 425 ft (129.5 m) long and 44 ft wide. If it were closed, the detour would be 1.2 mi (2 km).

Location

Open in Google Maps
CarriesEB US 30
CrossesSilver Ck & UP RR
Location0.7 Mi. E of W JCT US 61
RouteU.S. Route 30
CountyClinton County
StateIowa
Coordinates41.81662, -90.56828
Functional classRural Principal Arterial - Other

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.
Superstructure5 FairAll primary structural elements are sound but may have minor section loss, cracking, spalling or scour.
Substructure6 SatisfactoryStructural elements show some minor deterioration.
Channel and channel protection6 SatisfactoryStructural elements show some minor deterioration.
Last inspectionOctober 2022
Inspection intervalevery 24 months
Operating statusOpen, no restriction
ScourFoundations stable; scour above top of footing
Structural evaluation5: Somewhat better than minimum adequacy to tolerate being left in place as is
Deck geometry7: Better than present minimum criteria
Waterway adequacy8: Equal to present desirable criteria
Approach roadway alignment7: Better than present minimum criteria
Operating rating85.4 US tons
Inventory rating36.5 US tons

Structure

Structure typeStringer/Multi-beam or Girder
MaterialPrestressed Concrete
DeckConcrete, cast-in-place
Main spans6
Design loadHS 20
Structure length425 ft (129.5 m)
Longest span91 ft (27.7 m)
Deck width44 ft (13.3 m)
Roadway width40 ft (12.2 m)
Vertical clearance over deckUnrestricted

Traffic and service

Average daily traffic8,550 (2022)
Projected traffic8,550 by 2042
Trucks15%
Lanes on structure2
Traffic directionOne-way traffic
CarriesHighway
CrossesRailroad and waterway
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 proposedNone recorded
Estimated improvement cost—
NavigationNot applicable (no waterway)

Frequently asked questions

When was EB US 30 over Silver Ck & UP RR built?

It was built in 1970, making it 55 years old in 2025. It was reconstructed in 1975.

What condition is EB US 30 over Silver Ck & UP RR 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 2022.

How much traffic does EB US 30 over Silver Ck & UP RR carry?

About 8,550 vehicles per day (2022 count), of which roughly 15% are trucks.

How long is EB US 30 over Silver Ck & UP RR?

The structure is 425 ft (129.5 m) long with a longest span of 91 ft (27.7 m) and a deck 44 ft wide.

Who owns EB US 30 over Silver Ck & UP RR?

It is owned by the State Highway Agency.