US Bridges

HWY 91 over HWY 1

Fair

Multnomah County, Oregon · 3.0 MI NE Tigard Cc · Structure no. 08205 01W 00622

Built
1959
66 years old
Condition
Fair
inspected February 2024
Type
Box Beam or Girders - Multiple
Concrete Continuous
Length
250 ft
2 main spans
Daily traffic
9,741
2022 count
Owner
State
State Highway Agency

About this bridge

HWY 91 over HWY 1 is a concrete continuous box beam or girders - multiple carrying HWY 91 over HWY 1 in Multnomah County, Oregon. It was built in 1959, so it is 66 years old, older 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 9,741 vehicles a day, roughly 1% of them trucks, projected to reach 13,600 by 2042. The structure is 250 ft (76.3 m) long and 96 ft wide. If it were closed, the detour would be 1.9 mi (3 km).

Location

Open in Google Maps
CarriesHWY 91
CrossesHWY 1
Location3.0 MI NE Tigard Cc
RouteState Highway 99
CountyMultnomah County
StateOregon
Coordinates45.45361, -122.72102
Functional classUrban Other Principal Arterial

Condition and inspection

Fair

The lowest-rated primary component is rated 5 or 6. Minor deterioration is present but the structure is sound.

ComponentRatingMeaning
Deck6 SatisfactoryStructural elements show some minor deterioration.
Superstructure6 SatisfactoryStructural elements show some minor deterioration.
Substructure6 SatisfactoryStructural elements show some minor deterioration.
Last inspectionFebruary 2024
Inspection intervalevery 24 months
Operating statusOpen, no restriction
ScourBridge not over waterway
Structural evaluation3: Basically intolerable, requiring high priority of corrective action
Deck geometry2: Basically intolerable, requiring high priority of replacement
Approach roadway alignment8: Equal to present desirable criteria
Operating rating21.8 US tons
Inventory rating16.8 US tons

Structure

Structure typeBox Beam or Girders - Multiple
MaterialConcrete Continuous
DeckConcrete, cast-in-place
Main spans2 (+1 approach)
Design loadH 20
Structure length250 ft (76.3 m)
Longest span100 ft (30.4 m)
Deck width96 ft (29.3 m)
Roadway width82 ft (25 m)
Vertical clearance over deckUnrestricted

Traffic and service

Average daily traffic9,741 (2022)
Projected traffic13,600 by 2042
Trucks1%
Lanes on structure8
Traffic directionTwo-way traffic
CarriesOverpass structure at an interchange
CrossesHighway
Detour if closed1.9 mi (3 km)
TollOn a free road
National Highway SystemYes

Ownership and planned work

OwnerState Highway Agency
Maintained byState Highway Agency
Historic statusNot eligible for the National Register of Historic Places
Work proposedWidening of existing bridge without deck rehabilitation
Estimated improvement cost$4 million
NavigationNot applicable (no waterway)

Frequently asked questions

When was HWY 91 over HWY 1 built?

It was built in 1959, making it 66 years old in 2025.

What condition is HWY 91 over HWY 1 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 February 2024.

How much traffic does HWY 91 over HWY 1 carry?

About 9,741 vehicles per day (2022 count), of which roughly 1% are trucks.

How long is HWY 91 over HWY 1?

The structure is 250 ft (76.3 m) long with a longest span of 100 ft (30.4 m) and a deck 96 ft wide.

Who owns HWY 91 over HWY 1?

It is owned by the State Highway Agency.