US Bridges

Alpine Steet over Elec Lght Switch Lateral

Fair

Ada County, Idaho · In Boise · Structure no. 000000000033440

Built
1970
55 years old
Condition
Fair
inspected March 2023
Type
Culvert
Steel
Length
25 ft
1 main span
Daily traffic
730
2023 count
Owner
County
County Highway Agency

About this bridge

Alpine Steet over Elec Lght Switch Lateral is a steel culvert carrying Alpine Steet over Elec Lght Switch Lateral in Ada County, Idaho. It was built in 1970, so it is 55 years old, older 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 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 730 vehicles a day, projected to reach 1,095 by 2042. The structure is 25 ft (7.6 m) long and 38 ft wide. If it were closed, the detour would be 1.2 mi (2 km).

Location

Open in Google Maps
CarriesAlpine Steet
CrossesElec Lght Switch Lateral
LocationIn Boise
RouteCity Street 0
CountyAda County
StateIdaho
Coordinates43.60431, -116.22603
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
Channel and channel protection7 GoodSome minor problems.
Culvert5 FairAll primary structural elements are sound but may have minor section loss, cracking, spalling or scour.
Last inspectionMarch 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 geometry5: Somewhat better than minimum adequacy to tolerate being left in place as is
Waterway adequacy7: Better than present minimum criteria
Approach roadway alignment8: Equal to present desirable criteria
Operating rating83 US tons
Inventory rating81 US tons

Structure

Structure typeCulvert
MaterialSteel
DeckNot applicable
Main spans1
Design loadHS 20
Structure length25 ft (7.6 m)
Longest span25 ft (7.6 m)
Deck width38 ft (11.5 m)
Roadway width27 ft (8.2 m)
Vertical clearance over deckUnrestricted

Traffic and service

Average daily traffic730 (2023)
Projected traffic1,095 by 2042
Trucks0%
Lanes on structure2
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

OwnerCounty Highway Agency
Maintained byCounty Highway Agency
Historic statusHistorical significance not determinable at this time
Work proposedReplacement because of substandard load-carrying capacity or roadway geometry
Estimated improvement cost$579,000 (2021 estimate)
NavigationNo navigation control on waterway

Frequently asked questions

When was Alpine Steet over Elec Lght Switch Lateral built?

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

What condition is Alpine Steet over Elec Lght Switch Lateral 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 March 2023.

How much traffic does Alpine Steet over Elec Lght Switch Lateral carry?

About 730 vehicles per day (2023 count).

How long is Alpine Steet over Elec Lght Switch Lateral?

The structure is 25 ft (7.6 m) long with a longest span of 25 ft (7.6 m) and a deck 38 ft wide.

Who owns Alpine Steet over Elec Lght Switch Lateral?

It is owned by the County Highway Agency.