US Bridges

Birch Ave over Big Sioux River

Fair

Sioux County, Iowa · 097481404 · Structure no. 000000000313390

Built
1966
59 years old
Condition
Fair
inspected November 2022
Type
Stringer/Multi-beam or Girder
Steel Continuous
Length
405 ft
5 main spans
Daily traffic
450
2022 count
Owner
County
County Highway Agency

About this bridge

Birch Ave over Big Sioux River is a steel continuous stringer/multi-beam or girder carrying Birch Ave over Big Sioux River in Sioux County, Iowa. It was built in 1966, so it is 59 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 6 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 450 vehicles a day, roughly 15% of them trucks, projected to reach 450 by 2042. The structure is 405 ft (123.4 m) long and 30 ft wide. If it were closed, the detour would be 6.2 mi (10 km).

Location

Open in Google Maps
CarriesBirch Ave
CrossesBig Sioux River
Location097481404
RouteCounty Highway 0
CountySioux County
StateIowa
Coordinates43.22351, -96.49036
Functional classRural Major Collector

Condition and inspection

Fair

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

ComponentRatingMeaning
Deck8 Very GoodNo problems noted.
Superstructure6 SatisfactoryStructural elements show some minor deterioration.
Substructure7 GoodSome minor problems.
Channel and channel protection8 Very GoodNo problems noted.
Last inspectionNovember 2022
Inspection intervalevery 24 months
Operating statusOpen, no restriction
ScourFoundations stable; scour above top of footing
Structural evaluation6: Equal to present minimum criteria
Deck geometry5: Somewhat better than minimum adequacy to tolerate being left in place as is
Waterway adequacy8: Equal to present desirable criteria
Approach roadway alignment8: Equal to present desirable criteria
Operating rating63.6 US tons
Inventory rating38.3 US tons

Structure

Structure typeStringer/Multi-beam or Girder
MaterialSteel Continuous
DeckConcrete, cast-in-place
Main spans5
Design loadH 20
Structure length405 ft (123.4 m)
Longest span88 ft (26.8 m)
Deck width30 ft (9.1 m)
Roadway width28 ft (8.5 m)
Vertical clearance over deckUnrestricted

Traffic and service

Average daily traffic450 (2022)
Projected traffic450 by 2042
Trucks15%
Lanes on structure2
Traffic directionTwo-way traffic
CarriesHighway
CrossesWaterway
Detour if closed6.2 mi (10 km)
TollOn a free road
National Highway SystemNo

Ownership and planned work

OwnerCounty Highway Agency
Maintained byCounty 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 Birch Ave over Big Sioux River built?

It was built in 1966, making it 59 years old in 2025.

What condition is Birch Ave over Big Sioux River 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 November 2022.

How much traffic does Birch Ave over Big Sioux River carry?

About 450 vehicles per day (2022 count), of which roughly 15% are trucks.

How long is Birch Ave over Big Sioux River?

The structure is 405 ft (123.4 m) long with a longest span of 88 ft (26.8 m) and a deck 30 ft wide.

Who owns Birch Ave over Big Sioux River?

It is owned by the County Highway Agency.