US Bridges

College ST over Ralston Creek

Fair

Johnson County, Iowa · 079061000 · Structure no. 000000000500800

Built
1971
54 years old
Condition
Fair
inspected June 2023
Type
Frame
Concrete
Length
181 ft
1 main span
Daily traffic
1,940
2022 count
Owner
City
City or Municipal Highway Agency

About this bridge

College ST over Ralston Creek is a concrete frame carrying College ST over Ralston Creek in Johnson County, Iowa. It was built in 1971, so it is 54 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 1,940 vehicles a day, projected to reach 1,940 by 2043. The structure is 181 ft (55.2 m) long and 64 ft wide. If it were closed, the detour would be 1.2 mi (2 km).

Location

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CarriesCollege ST
CrossesRalston Creek
Location079061000
RouteCity Street 0
CountyJohnson County
StateIowa
Coordinates41.65894, -91.52932
Functional classUrban 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.
Substructure7 GoodSome minor problems.
Channel and channel protection7 GoodSome minor problems.
Last inspectionJune 2023
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 geometry2: Basically intolerable, requiring high priority of replacement
Waterway adequacy9: Superior to present desirable criteria
Approach roadway alignment7: Better than present minimum criteria
Operating rating30.8 US tons
Inventory rating23.9 US tons

Structure

Structure typeFrame
MaterialConcrete
DeckConcrete, cast-in-place
Main spans1
Design loadHS 20
Structure length181 ft (55.2 m)
Longest span150 ft (45.7 m)
Deck width64 ft (19.5 m)
Roadway width48 ft (14.6 m)
Vertical clearance over deckUnrestricted

Traffic and service

Average daily traffic1,940 (2022)
Projected traffic1,940 by 2043
Trucks0%
Lanes on structure4
Traffic directionTwo-way traffic
CarriesHighway and pedestrian
CrossesWaterway
Detour if closed1.2 mi (2 km)
TollOn a free road
National Highway SystemNo

Ownership and planned work

OwnerCity or Municipal Highway Agency
Maintained byCity or Municipal Highway Agency
Historic statusNot eligible for the National Register of Historic Places
Work proposedRehabilitation because of general structure deterioration or inadequate strength
Estimated improvement cost—
NavigationNo navigation control on waterway

Frequently asked questions

When was College ST over Ralston Creek built?

It was built in 1971, making it 54 years old in 2025.

What condition is College ST over Ralston 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 June 2023.

How much traffic does College ST over Ralston Creek carry?

About 1,940 vehicles per day (2022 count).

How long is College ST over Ralston Creek?

The structure is 181 ft (55.2 m) long with a longest span of 150 ft (45.7 m) and a deck 64 ft wide.

Who owns College ST over Ralston Creek?

It is owned by the City or Municipal Highway Agency.