US Bridges

STC3928;S Eagle RD over Mason Creek Feeder Canal

Fair

Ada County, Idaho · 0.4 N. 3.3 E. Kuna · Structure no. 000000000026270

Built
1990
35 years old
Condition
Fair
inspected October 2024
Type
Frame
Concrete
Length
35 ft
1 main span
Daily traffic
570
2023 count
Owner
County
County Highway Agency

About this bridge

STC3928;S Eagle RD over Mason Creek Feeder Canal is a concrete frame carrying STC3928;S Eagle RD over Mason Creek Feeder Canal in Ada County, Idaho. It was built in 1990, so it is 35 years old, younger than the Idaho average of 45.3 years.

The most recent inspection reported to the Federal Highway Administration rates it in fair condition with a lowest component rating of 6 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 570 vehicles a day, roughly 6% of them trucks, projected to reach 855 by 2042. The structure is 35 ft (10.7 m) long and 35 ft wide. If it were closed, the detour would be 1.9 mi (3 km).

Location

Open in Google Maps
CarriesSTC3928;S Eagle RD
CrossesMason Creek Feeder Canal
Location0.4 N. 3.3 E. Kuna
RouteCounty Highway 3928
CountyAda County
StateIdaho
Coordinates43.49861, -116.35444
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
Deck7 GoodSome minor problems.
Superstructure7 GoodSome minor problems.
Substructure6 SatisfactoryStructural elements show some minor deterioration.
Channel and channel protection9 ExcellentNo problems noted.
Last inspectionOctober 2024
Inspection intervalevery 48 months
Operating statusOpen, no restriction
ScourFoundations stable; scour above top of footing
Structural evaluation6: Equal to present minimum criteria
Deck geometry6: Equal to present minimum criteria
Waterway adequacy9: Superior to present desirable criteria
Approach roadway alignment8: Equal to present desirable criteria
Operating rating110.1 US tons
Inventory rating110.1 US tons

Structure

Structure typeFrame
MaterialConcrete
DeckConcrete, cast-in-place
Main spans1
Design loadHS 20
Structure length35 ft (10.7 m)
Longest span35 ft (10.7 m)
Deck width35 ft (10.7 m)
Roadway width31 ft (9.4 m)
Vertical clearance over deckUnrestricted

Traffic and service

Average daily traffic570 (2023)
Projected traffic855 by 2042
Trucks6%
Lanes on structure2
Traffic directionTwo-way traffic
CarriesHighway
CrossesWaterway
Detour if closed1.9 mi (3 km)
TollOn a free road
National Highway SystemNo

Ownership and planned work

OwnerCounty Highway Agency
Maintained byCounty Highway Agency
Historic statusHistorical significance not determinable at this time
Work proposedNone recorded
Estimated improvement cost—
NavigationNo navigation control on waterway

Frequently asked questions

When was STC3928;S Eagle RD over Mason Creek Feeder Canal built?

It was built in 1990, making it 35 years old in 2025.

What condition is STC3928;S Eagle RD over Mason Creek Feeder Canal 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 October 2024.

How much traffic does STC3928;S Eagle RD over Mason Creek Feeder Canal carry?

About 570 vehicles per day (2023 count), of which roughly 6% are trucks.

How long is STC3928;S Eagle RD over Mason Creek Feeder Canal?

The structure is 35 ft (10.7 m) long with a longest span of 35 ft (10.7 m) and a deck 35 ft wide.

Who owns STC3928;S Eagle RD over Mason Creek Feeder Canal?

It is owned by the County Highway Agency.