US Bridges

Local - 770th over Waterway

Good

Cass County, Iowa · 077341306 · Structure no. 000000000100321

Built
1985
40 years old
Condition
Good
inspected March 2024
Type
Slab
Concrete Continuous
Length
103 ft
3 main spans
Daily traffic
26
2022 count
Owner
County
County Highway Agency

About this bridge

Local - 770th over Waterway is a concrete continuous slab carrying Local - 770th over Waterway in Cass County, Iowa. It was built in 1985, so it is 40 years old, younger than the Iowa average of 45.5 years.

The most recent inspection reported to the Federal Highway Administration rates it in good condition with a lowest component rating of 7 out of 9. All primary components (deck, superstructure, substructure, or culvert) are rated 7 or higher. No significant problems were noted.

It carries about 26 vehicles a day, projected to reach 26 by 2044. The structure is 103 ft (31.4 m) long and 27 ft wide. If it were closed, the detour would be 3.7 mi (6 km).

Location

Open in Google Maps
CarriesLocal - 770th
CrossesWaterway
Location077341306
RouteCounty Highway 0
CountyCass County
StateIowa
Coordinates41.46097, -94.71991
Functional classRural Local

Condition and inspection

Good

All primary components (deck, superstructure, substructure, or culvert) are rated 7 or higher. No significant problems were noted.

ComponentRatingMeaning
Deck7 GoodSome minor problems.
Superstructure7 GoodSome minor problems.
Substructure7 GoodSome minor problems.
Channel and channel protection6 SatisfactoryStructural elements show some minor deterioration.
Last inspectionMarch 2024
Inspection intervalevery 48 months
Operating statusOpen, no restriction
ScourFoundations stable; scour above top of footing
Structural evaluation7: Better than present minimum criteria
Deck geometry6: Equal to present minimum criteria
Waterway adequacy8: Equal to present desirable criteria
Approach roadway alignment6: Equal to present minimum criteria
Operating rating65.1 US tons
Inventory rating36.7 US tons

Structure

Structure typeSlab
MaterialConcrete Continuous
DeckConcrete, cast-in-place
Main spans3
Design loadH 20
Structure length103 ft (31.4 m)
Longest span39 ft (11.9 m)
Deck width27 ft (8.3 m)
Roadway width24 ft (7.3 m)
Vertical clearance over deckUnrestricted

Traffic and service

Average daily traffic26 (2022)
Projected traffic26 by 2044
Trucks0%
Lanes on structure2
Traffic directionTwo-way traffic
CarriesHighway
CrossesWaterway
Detour if closed3.7 mi (6 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 proposedOther structural work, including hydraulic replacements
Estimated improvement cost$30,000 (2024 estimate)
NavigationNo navigation control on waterway

Frequently asked questions

When was Local - 770th over Waterway built?

It was built in 1985, making it 40 years old in 2025.

What condition is Local - 770th over Waterway in?

The National Bridge Inventory rates it in good condition. All primary components (deck, superstructure, substructure, or culvert) are rated 7 or higher. No significant problems were noted. The last reported inspection was in March 2024.

How much traffic does Local - 770th over Waterway carry?

About 26 vehicles per day (2022 count).

How long is Local - 770th over Waterway?

The structure is 103 ft (31.4 m) long with a longest span of 39 ft (11.9 m) and a deck 27 ft wide.

Who owns Local - 770th over Waterway?

It is owned by the County Highway Agency.