US Bridges

SR 7 over Nisqually River

Fair

Lewis County, Washington · 16.3 N JCT SR 508 · Structure no. 0004348A0000000

Built
1953
72 years old
Condition
Fair
inspected February 2024
Type
Truss - Thru
Steel
Length
247 ft
1 main span
Daily traffic
2,872
2023 count
Owner
State
State Highway Agency

About this bridge

SR 7 over Nisqually River is a steel truss - thru carrying SR 7 over Nisqually River in Lewis County, Washington. It was built in 1953, so it is 72 years old, older than the Washington average of 49.8 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 2,872 vehicles a day, roughly 13% of them trucks, projected to reach 3,544 by 2039. The structure is 247 ft (75.3 m) long and 34 ft wide. If it were closed, the detour would be 98.8 mi (159 km).

Location

Open in Google Maps
CarriesSR 7
CrossesNisqually River
Location16.3 N JCT SR 508
RouteState Highway 7
CountyLewis County
StateWashington
Coordinates46.76194, -122.19217
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.
Substructure7 GoodSome minor problems.
Channel and channel protection5 FairAll primary structural elements are sound but may have minor section loss, cracking, spalling or scour.
Last inspectionFebruary 2024
Inspection intervalevery 24 months
Operating statusOpen, no restriction
ScourFoundations stable; scour within limits of footing or piles
Structural evaluation6: Equal to present minimum criteria
Deck geometry4: Meets minimum tolerable limits to be left in place as is
Waterway adequacy5: Somewhat better than minimum adequacy to tolerate being left in place as is
Approach roadway alignment8: Equal to present desirable criteria
Operating rating56 US tons
Inventory rating33 US tons

Structure

Structure typeTruss - Thru
MaterialSteel
DeckConcrete, cast-in-place
Main spans1 (+1 approach)
Design loadHS 20
Structure length247 ft (75.3 m)
Longest span200 ft (61 m)
Deck width34 ft (10.4 m)
Roadway width28 ft (8.5 m)
Vertical clearance over deck15 ft (4.6 m)

Traffic and service

Average daily traffic2,872 (2023)
Projected traffic3,544 by 2039
Trucks13%
Lanes on structure2
Traffic directionTwo-way traffic
CarriesHighway and pedestrian
CrossesWaterway
Detour if closed98.8 mi (159 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 proposedRehabilitation because of general structure deterioration or inadequate strength
Estimated improvement cost$3.8 million (2022 estimate)
NavigationNo navigation control on waterway

Frequently asked questions

When was SR 7 over Nisqually River built?

It was built in 1953, making it 72 years old in 2025.

What condition is SR 7 over Nisqually River 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 SR 7 over Nisqually River carry?

About 2,872 vehicles per day (2023 count), of which roughly 13% are trucks.

How long is SR 7 over Nisqually River?

The structure is 247 ft (75.3 m) long with a longest span of 200 ft (61 m) and a deck 34 ft wide.

Who owns SR 7 over Nisqually River?

It is owned by the State Highway Agency.