US Bridges

Niles Trail over Harris Grove Creek

Fair

Harrison County, Iowa · 079433603 · Structure no. 000000000178221

Built
1975
50 years old
Condition
Fair
inspected December 2024
Type
Stringer/Multi-beam or Girder
Steel
Length
33 ft
1 main span
Daily traffic
29
2022 count
Owner
County
County Highway Agency

About this bridge

Niles Trail over Harris Grove Creek is a steel stringer/multi-beam or girder carrying Niles Trail over Harris Grove Creek in Harrison 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 29 vehicles a day, projected to reach 29 by 2044. The structure is 33 ft (10.1 m) long and 30 ft wide. If it were closed, the detour would be 5 mi (8 km).

Location

Open in Google Maps
CarriesNiles Trail
CrossesHarris Grove Creek
Location079433603
RouteCounty Highway 0
CountyHarrison County
StateIowa
Coordinates41.60674, -95.80419
Functional classRural Local

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.
Superstructure5 FairAll primary structural elements are sound but may have minor section loss, cracking, spalling or scour.
Substructure5 FairAll primary structural elements are sound but may have minor section loss, cracking, spalling or scour.
Channel and channel protection5 FairAll primary structural elements are sound but may have minor section loss, cracking, spalling or scour.
Last inspectionDecember 2024
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 alignment6: Equal to present minimum criteria
Operating rating42.2 US tons
Inventory rating25.2 US tons

Structure

Structure typeStringer/Multi-beam or Girder
MaterialSteel
DeckCorrugated steel
Main spans1
Design loadUnknown
Structure length33 ft (10.1 m)
Longest span31 ft (9.4 m)
Deck width30 ft (9.1 m)
Roadway width30 ft (9.1 m)
Vertical clearance over deckUnrestricted

Traffic and service

Average daily traffic29 (2022)
Projected traffic29 by 2044
Trucks0%
Lanes on structure2
Traffic directionTwo-way traffic
CarriesHighway
CrossesWaterway
Detour if closed5 mi (8 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 Niles Trail over Harris Grove Creek built?

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

What condition is Niles Trail over Harris Grove Creek 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 December 2024.

How much traffic does Niles Trail over Harris Grove Creek carry?

About 29 vehicles per day (2022 count).

How long is Niles Trail over Harris Grove Creek?

The structure is 33 ft (10.1 m) long with a longest span of 31 ft (9.4 m) and a deck 30 ft wide.

Who owns Niles Trail over Harris Grove Creek?

It is owned by the County Highway Agency.