US Bridges

CO RD G18 over West Nishnabotna River

Fair

Pottawattamie County, Iowa · 077391703 · Structure no. 000000000043681

Built
1975
50 years old
Condition
Fair
inspected May 2023
Type
Stringer/Multi-beam or Girder
Prestressed Concrete
Length
221 ft
3 main spans
Daily traffic
967
2021 count
Owner
County
County Highway Agency

About this bridge

CO RD G18 over West Nishnabotna River is a prestressed concrete stringer/multi-beam or girder carrying CO RD G18 over West Nishnabotna River in Pottawattamie County, Iowa. It was built in 1975, so it is 50 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 967 vehicles a day, roughly 12% of them trucks, projected to reach 967 by 2043. The structure is 221 ft (67.4 m) long and 39 ft wide. If it were closed, the detour would be 3.1 mi (5 km).

Location

Open in Google Maps
CarriesCO RD G18
CrossesWest Nishnabotna River
Location077391703
RouteCounty Highway 0
CountyPottawattamie County
StateIowa
Coordinates41.47669, -95.35327
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
Deck5 FairAll primary structural elements are sound but may have minor section loss, cracking, spalling or scour.
Superstructure8 Very GoodNo problems noted.
Substructure6 SatisfactoryStructural elements show some minor deterioration.
Channel and channel protection6 SatisfactoryStructural elements show some minor deterioration.
Last inspectionMay 2023
Inspection intervalevery 24 months
Operating statusOpen, no restriction
ScourFoundations stable; scour above top of footing
Structural evaluation6: Equal to present minimum criteria
Deck geometry7: Better than present minimum criteria
Waterway adequacy8: Equal to present desirable criteria
Approach roadway alignment7: Better than present minimum criteria
Operating rating48.9 US tons
Inventory rating36 US tons

Structure

Structure typeStringer/Multi-beam or Girder
MaterialPrestressed Concrete
DeckConcrete, cast-in-place
Main spans3
Design loadHS 20
Structure length221 ft (67.4 m)
Longest span80 ft (24.4 m)
Deck width39 ft (12 m)
Roadway width36 ft (11 m)
Vertical clearance over deckUnrestricted

Traffic and service

Average daily traffic967 (2021)
Projected traffic967 by 2043
Trucks12%
Lanes on structure2
Traffic directionTwo-way traffic
CarriesHighway
CrossesWaterway
Detour if closed3.1 mi (5 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 CO RD G18 over West Nishnabotna River built?

It was built in 1975, making it 50 years old in 2025.

What condition is CO RD G18 over West Nishnabotna 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 May 2023.

How much traffic does CO RD G18 over West Nishnabotna River carry?

About 967 vehicles per day (2021 count), of which roughly 12% are trucks.

How long is CO RD G18 over West Nishnabotna River?

The structure is 221 ft (67.4 m) long with a longest span of 80 ft (24.4 m) and a deck 39 ft wide.

Who owns CO RD G18 over West Nishnabotna River?

It is owned by the County Highway Agency.