US Bridges

FM - 690th over Waterway

Poor

Cass County, Iowa · 076351502 · Structure no. 000000000099300

Built
1970
55 years old
Condition
Poor
inspected March 2024
Type
Slab
Concrete Continuous
Length
78 ft
3 main spans
Daily traffic
450
2022 count
Owner
County
County Highway Agency

About this bridge

FM - 690th over Waterway is a concrete continuous slab carrying FM - 690th over Waterway in Cass County, Iowa. It was built in 1970, so it is 55 years old, older than the Iowa average of 45.5 years.

The most recent inspection reported to the Federal Highway Administration rates it in poor condition with a lowest component rating of 4 out of 9. The lowest-rated primary component is rated 4 or below, indicating advanced deterioration. Poor does not mean unsafe; such bridges are inspected more often and may carry load restrictions.

It carries about 450 vehicles a day, roughly 24% of them trucks, projected to reach 450 by 2044. The structure is 78 ft (23.8 m) long and 32 ft wide. If it were closed, the detour would be 6.2 mi (10 km).

Location

Open in Google Maps
CarriesFM - 690th
CrossesWaterway
Location076351502
RouteCounty Highway 0
CountyCass County
StateIowa
Coordinates41.38076, -94.87236
Functional classRural Major Collector

Condition and inspection

Poor

The lowest-rated primary component is rated 4 or below, indicating advanced deterioration. Poor does not mean unsafe; such bridges are inspected more often and may carry load restrictions.

ComponentRatingMeaning
Deck4 PoorAdvanced section loss, deterioration, spalling or scour.
Superstructure4 PoorAdvanced section loss, deterioration, spalling or scour.
Substructure6 SatisfactoryStructural elements show some minor deterioration.
Channel and channel protection6 SatisfactoryStructural elements show some minor deterioration.
Last inspectionMarch 2024
Inspection intervalevery 24 months
Operating statusOpen, no restriction
ScourFoundations stable; scour above top of footing
Structural evaluation4: Meets minimum tolerable limits to be left in place as is
Deck geometry6: Equal to present minimum criteria
Waterway adequacy7: Better than present minimum criteria
Approach roadway alignment7: Better than present minimum criteria
Operating rating57.8 US tons
Inventory rating36.4 US tons

Structure

Structure typeSlab
MaterialConcrete Continuous
DeckConcrete, cast-in-place
Main spans3
Design loadH 20
Structure length78 ft (23.8 m)
Longest span29 ft (8.8 m)
Deck width32 ft (9.8 m)
Roadway width30 ft (9.1 m)
Vertical clearance over deckUnrestricted

Traffic and service

Average daily traffic450 (2022)
Projected traffic450 by 2044
Trucks24%
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 proposedReplacement because of substandard load-carrying capacity or roadway geometry
Estimated improvement cost—
NavigationNo navigation control on waterway

Frequently asked questions

When was FM - 690th over Waterway built?

It was built in 1970, making it 55 years old in 2025.

What condition is FM - 690th over Waterway in?

The National Bridge Inventory rates it in poor condition. The lowest-rated primary component is rated 4 or below, indicating advanced deterioration. Poor does not mean unsafe; such bridges are inspected more often and may carry load restrictions. The last reported inspection was in March 2024.

How much traffic does FM - 690th over Waterway carry?

About 450 vehicles per day (2022 count), of which roughly 24% are trucks.

How long is FM - 690th over Waterway?

The structure is 78 ft (23.8 m) long with a longest span of 29 ft (8.8 m) and a deck 32 ft wide.

Who owns FM - 690th over Waterway?

It is owned by the County Highway Agency.