US Bridges

Or 99W (hwy 91) over Baskett Slough

FairPosted for load

Polk County, Oregon · 065 MI N Monmouth · Structure no. 00827A01W 05633

Built
1923
102 years old, rebuilt 1960
Condition
Fair
inspected April 2023
Type
Tee Beam
Concrete Continuous
Length
41 ft
2 main spans
Daily traffic
12,985
2022 count
Owner
State
State Highway Agency

About this bridge

Or 99W (hwy 91) over Baskett Slough is a concrete continuous tee beam carrying Or 99W (hwy 91) over Baskett Slough in Polk County, Oregon. It was built in 1923 and reconstructed in 1960, so it is 102 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. Its operating status is: posted for other load-capacity restriction.

It carries about 12,985 vehicles a day, roughly 16% of them trucks, projected to reach 14,800 by 2042. The structure is 41 ft (12.6 m) long and 45 ft wide. If it were closed, the detour would be 16.2 mi (26 km).

Location

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CarriesOr 99W (hwy 91)
CrossesBaskett Slough
Location065 MI N Monmouth
RouteState Highway 99
CountyPolk County
StateOregon
Coordinates44.95075, -123.22855
Functional classRural Minor 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
Deck7 GoodSome minor problems.
Superstructure6 SatisfactoryStructural elements show some minor deterioration.
Substructure6 SatisfactoryStructural elements show some minor deterioration.
Channel and channel protection8 Very GoodNo problems noted.
Last inspectionApril 2023
Inspection intervalevery 24 months
Operating statusPosted for other load-capacity restriction
ScourFoundations stable; scour above top of footing
Structural evaluation4: Meets minimum tolerable limits to be left in place as is
Deck geometry5: Somewhat better than minimum adequacy to tolerate being left in place as is
Waterway adequacy8: Equal to present desirable criteria
Approach roadway alignment8: Equal to present desirable criteria
Operating rating25.4 US tons
Inventory rating19.6 US tons

Structure

Structure typeTee Beam
MaterialConcrete Continuous
DeckConcrete, cast-in-place
Main spans2
Design loadH 15
Structure length41 ft (12.6 m)
Longest span21 ft (6.3 m)
Deck width45 ft (13.7 m)
Roadway width40 ft (12.2 m)
Vertical clearance over deckUnrestricted

Traffic and service

Average daily traffic12,985 (2022)
Projected traffic14,800 by 2042
Trucks16%
Lanes on structure2
Traffic directionTwo-way traffic
CarriesHighway
CrossesWaterway
Detour if closed16.2 mi (26 km)
TollOn a free road
National Highway SystemNo

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$211,000
NavigationNo navigation control on waterway

Frequently asked questions

When was Or 99W (hwy 91) over Baskett Slough built?

It was built in 1923, making it 102 years old in 2025. It was reconstructed in 1960.

What condition is Or 99W (hwy 91) over Baskett 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 April 2023.

How much traffic does Or 99W (hwy 91) over Baskett Slough carry?

About 12,985 vehicles per day (2022 count), of which roughly 16% are trucks.

How long is Or 99W (hwy 91) over Baskett Slough?

The structure is 41 ft (12.6 m) long with a longest span of 21 ft (6.3 m) and a deck 45 ft wide.

Who owns Or 99W (hwy 91) over Baskett Slough?

It is owned by the State Highway Agency.