US Bridges

US 20 over Stream

Good

Grundy County, Iowa · 2.0 Miles East of SR T55 · Structure no. 000000000607695

Built
1999
26 years old
Condition
Good
inspected February 2024
Type
Culvert
Concrete Continuous
Length
21 ft
2 main spans
Daily traffic
14,500
2022 count
Owner
State
State Highway Agency

About this bridge

US 20 over Stream is a concrete continuous culvert carrying US 20 over Stream in Grundy County, Iowa. It was built in 1999, so it is 26 years old, younger than the Iowa average of 45.5 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 14,500 vehicles a day, roughly 20% of them trucks, projected to reach 14,500 by 2044. The structure is 21 ft (6.4 m) long. If it were closed, the detour would be 1.2 mi (2 km).

CarriesUS 20
CrossesStream
Location2.0 Miles East of SR T55
RouteU.S. Route 20
StateIowa
Coordinates42.46402, -92.59437
Functional classRural Principal Arterial - Other

Condition and inspection

Good

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

ComponentRatingMeaning
Channel and channel protection8 Very GoodNo problems noted.
Culvert7 GoodSome minor problems.
Last inspectionFebruary 2024
Inspection intervalevery 24 months
Operating statusOpen, no restriction
ScourFoundations stable; scour above top of footing
Structural evaluation7: Better than present minimum criteria
Waterway adequacy8: Equal to present desirable criteria
Approach roadway alignment8: Equal to present desirable criteria
Operating rating70.8 US tons
Inventory rating54.7 US tons

Structure

Structure typeCulvert
MaterialConcrete Continuous
DeckNot applicable
Main spans2
Design loadHS 20
Structure length21 ft (6.4 m)
Longest span10 ft (3 m)
Deck width0 ft (0 m)
Roadway width0 ft (0 m)
Vertical clearance over deckUnrestricted

Traffic and service

Average daily traffic14,500 (2022)
Projected traffic14,500 by 2044
Trucks20%
Lanes on structure4
Traffic directionTwo-way traffic
CarriesHighway
CrossesWaterway
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—
NavigationNo navigation control on waterway

Frequently asked questions

When was US 20 over Stream built?

It was built in 1999, making it 26 years old in 2025.

What condition is US 20 over Stream 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 February 2024.

How much traffic does US 20 over Stream carry?

About 14,500 vehicles per day (2022 count), of which roughly 20% are trucks.

How long is US 20 over Stream?

The structure is 21 ft (6.4 m) long with a longest span of 10 ft (3 m).

Who owns US 20 over Stream?

It is owned by the State Highway Agency.