US Bridges

SR 171 over I-90

Good

Grant County, Washington · JCT I-90 · Structure no. 0015898A0000000

Built
2001
24 years old
Condition
Good
inspected September 2023
Type
Stringer/Multi-beam or Girder
Prestressed Concrete Continuous
Length
222 ft
2 main spans
Daily traffic
11,072
2023 count
Owner
State
State Highway Agency

About this bridge

SR 171 over I-90 is a prestressed concrete continuous stringer/multi-beam or girder carrying SR 171 over I-90 in Grant County, Washington. It was built in 2001, so it is 24 years old, younger than the Washington average of 49.8 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 11,072 vehicles a day, roughly 5% of them trucks, projected to reach 12,781 by 2039. The structure is 222 ft (67.7 m) long and 79 ft wide. If it were closed, the detour would be 9.9 mi (16 km).

Location

Open in Google Maps
CarriesSR 171
CrossesI-90
LocationJCT I-90
RouteState Highway 171
CountyGrant County
StateWashington
Coordinates47.10092, -119.31647
Functional classUrban Other Principal Arterial

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.
Last inspectionSeptember 2023
Inspection intervalevery 24 months
Operating statusOpen, no restriction
ScourBridge not over waterway
Structural evaluation7: Better than present minimum criteria
Deck geometry7: Better than present minimum criteria
Approach roadway alignment8: Equal to present desirable criteria
Operating rating89.9 US tons
Inventory rating54 US tons

Structure

Structure typeStringer/Multi-beam or Girder
MaterialPrestressed Concrete Continuous
DeckConcrete, cast-in-place
Main spans2
Design loadHS 25 or greater
Structure length222 ft (67.7 m)
Longest span111 ft (33.8 m)
Deck width79 ft (24 m)
Roadway width65 ft (19.8 m)
Vertical clearance over deckUnrestricted

Traffic and service

Average daily traffic11,072 (2023)
Projected traffic12,781 by 2039
Trucks5%
Lanes on structure4
Traffic directionTwo-way traffic
CarriesHighway
CrossesHighway
Detour if closed9.9 mi (16 km)
TollOn a free road
National Highway SystemYes

Ownership and planned work

OwnerState Highway Agency
Maintained byState Highway Agency
Historic statusHistorical significance not determinable at this time
Work proposedRehabilitation because of general structure deterioration or inadequate strength
Estimated improvement cost$7.1 million (2022 estimate)
NavigationNot applicable (no waterway)

Frequently asked questions

When was SR 171 over I-90 built?

It was built in 2001, making it 24 years old in 2025.

What condition is SR 171 over I-90 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 September 2023.

How much traffic does SR 171 over I-90 carry?

About 11,072 vehicles per day (2023 count), of which roughly 5% are trucks.

How long is SR 171 over I-90?

The structure is 222 ft (67.7 m) long with a longest span of 111 ft (33.8 m) and a deck 79 ft wide.

Who owns SR 171 over I-90?

It is owned by the State Highway Agency.