US Bridges

US101(HWY009) NB over Southport Slough

Good

Coos County, Oregon · 04.8 MI S Coos Bay · Structure no. 22491 009 24404

Built
2018
7 years old
Condition
Good
inspected May 2023
Type
Slab
Prestressed Concrete
Length
50 ft
1 main span
Daily traffic
3,794
2022 count
Owner
State
State Highway Agency

About this bridge

US101(HWY009) NB over Southport Slough is a prestressed concrete slab carrying US101(HWY009) NB over Southport Slough in Coos County, Oregon. It was built in 2018, so it is 7 years old, younger than the Oregon average of 49.9 years.

The most recent inspection reported to the Federal Highway Administration rates it in good condition with a lowest component rating of 7 out of 9. All primary components (deck, superstructure, substructure, or culvert) are rated 7 or higher. No significant problems were noted.

It carries about 3,794 vehicles a day, roughly 7% of them trucks, projected to reach 3,850 by 2042. The structure is 50 ft (15.2 m) long and 44 ft wide.

Location

Open in Google Maps
CarriesUS101(HWY009) NB
CrossesSouthport Slough
Location04.8 MI S Coos Bay
RouteU.S. Route 101
CountyCoos County
StateOregon
Coordinates43.29546, -124.21649
Functional classRural Principal Arterial - Other

Condition and inspection

Good

All primary components (deck, superstructure, substructure, or culvert) are rated 7 or higher. No significant problems were noted.

ComponentRatingMeaning
Deck7 GoodSome minor problems.
Superstructure7 GoodSome minor problems.
Substructure7 GoodSome minor problems.
Channel and channel protection8 Very GoodNo problems noted.
Last inspectionMay 2023
Inspection intervalevery 24 months
Operating statusOpen, no restriction
ScourFoundations stable; scour within limits of footing or piles
Structural evaluation7: Better than present minimum criteria
Deck geometry7: Better than present minimum criteria
Waterway adequacy8: Equal to present desirable criteria
Approach roadway alignment8: Equal to present desirable criteria
Operating rating83.2 US tons
Inventory rating64.3 US tons

Structure

Structure typeSlab
MaterialPrestressed Concrete
DeckConcrete, cast-in-place
Main spans1
Design loadHL 93
Structure length50 ft (15.2 m)
Longest span50 ft (15.2 m)
Deck width44 ft (13.4 m)
Roadway width41 ft (12.4 m)
Vertical clearance over deckUnrestricted

Traffic and service

Average daily traffic3,794 (2022)
Projected traffic3,850 by 2042
Trucks7%
Lanes on structure2
Traffic directionOne-way traffic
CarriesHighway
CrossesWaterway
Detour if closed—
TollOn a free road
National Highway SystemYes
Strategic Highway NetworkNon-Interstate STRAHNET route

Ownership and planned work

OwnerState Highway Agency
Maintained byState 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 US101(HWY009) NB over Southport Slough built?

It was built in 2018, making it 7 years old in 2025.

What condition is US101(HWY009) NB over Southport Slough in?

The National Bridge Inventory rates it in good condition. All primary components (deck, superstructure, substructure, or culvert) are rated 7 or higher. No significant problems were noted. The last reported inspection was in May 2023.

How much traffic does US101(HWY009) NB over Southport Slough carry?

About 3,794 vehicles per day (2022 count), of which roughly 7% are trucks.

How long is US101(HWY009) NB over Southport Slough?

The structure is 50 ft (15.2 m) long with a longest span of 50 ft (15.2 m) and a deck 44 ft wide.

Who owns US101(HWY009) NB over Southport Slough?

It is owned by the State Highway Agency.