US Bridges

NE 47th Ave over B-93 X Columbia Slough

Fair

Multnomah County, Oregon · 00.2 MI N of Col Blvd · Structure no. 51C07A000 00001

Built
1991
34 years old
Condition
Fair
inspected July 2024
Type
Slab
Prestressed Concrete
Length
55 ft
1 main span
Daily traffic
6,019
2020 count
Owner
City
City or Municipal Highway Agency

About this bridge

NE 47th Ave over B-93 X Columbia Slough is a prestressed concrete slab carrying NE 47th Ave over B-93 X Columbia Slough in Multnomah County, Oregon. It was built in 1991, so it is 34 years old, younger than the Oregon average of 49.9 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 6,019 vehicles a day, roughly 10% of them trucks, projected to reach 6,638 by 2025. The structure is 55 ft (16.8 m) long and 45 ft wide. If it were closed, the detour would be 3.1 mi (5 km).

Location

Open in Google Maps
CarriesNE 47th Ave
CrossesB-93 X Columbia Slough
Location00.2 MI N of Col Blvd
RouteCounty Highway C0000
CountyMultnomah County
StateOregon
Coordinates45.57734, -122.614
Functional classUrban 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
Deck8 Very GoodNo problems noted.
Superstructure8 Very GoodNo problems noted.
Substructure6 SatisfactoryStructural elements show some minor deterioration.
Channel and channel protection6 SatisfactoryStructural elements show some minor deterioration.
Last inspectionJuly 2024
Inspection intervalevery 24 months
Operating statusOpen, no restriction
ScourUnknown foundation; not evaluated for scour
Structural evaluation6: Equal to present minimum criteria
Deck geometry4: Meets minimum tolerable limits to be left in place as is
Waterway adequacy7: Better than present minimum criteria
Approach roadway alignment6: Equal to present minimum criteria
Operating rating80 US tons
Inventory rating48 US tons

Structure

Structure typeSlab
MaterialPrestressed Concrete
DeckConcrete, precast panels
Main spans1
Design loadHS 25 or greater
Structure length55 ft (16.8 m)
Longest span52 ft (15.9 m)
Deck width45 ft (13.8 m)
Roadway width32 ft (9.8 m)
Vertical clearance over deckUnrestricted

Traffic and service

Average daily traffic6,019 (2020)
Projected traffic6,638 by 2025
Trucks10%
Lanes on structure2
Traffic directionTwo-way traffic
CarriesHighway and pedestrian
CrossesWaterway
Detour if closed3.1 mi (5 km)
TollOn a free road
National Highway SystemYes

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 proposedNone recorded
Estimated improvement cost—
NavigationNo navigation control on waterway

Frequently asked questions

When was NE 47th Ave over B-93 X Columbia Slough built?

It was built in 1991, making it 34 years old in 2025.

What condition is NE 47th Ave over B-93 X Columbia Slough 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 July 2024.

How much traffic does NE 47th Ave over B-93 X Columbia Slough carry?

About 6,019 vehicles per day (2020 count), of which roughly 10% are trucks.

How long is NE 47th Ave over B-93 X Columbia Slough?

The structure is 55 ft (16.8 m) long with a longest span of 52 ft (15.9 m) and a deck 45 ft wide.

Who owns NE 47th Ave over B-93 X Columbia Slough?

It is owned by the City or Municipal Highway Agency.