US Bridges

SR 304 over Sinclair Inlet

Fair

Kitsap County, Washington · 0.4 E JCT SR 303 · Structure no. 0013663A0000000

Built
1990
35 years old
Condition
Fair
inspected May 2023
Type
Movable - Lift
Steel
Length
105 ft
1 main span
Daily traffic
3,600
2010 count
Owner
State
State Highway Agency

About this bridge

SR 304 over Sinclair Inlet is a steel movable - lift carrying SR 304 over Sinclair Inlet in Kitsap County, Washington. It was built in 1990, so it is 35 years old, younger 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 3,600 vehicles a day, roughly 1% of them trucks, projected to reach 4,320 by 2031. The structure is 105 ft (32 m) long and 25 ft wide.

Location

Open in Google Maps
CarriesSR 304
CrossesSinclair Inlet
Location0.4 E JCT SR 303
RouteState Highway 304
CountyKitsap County
StateWashington
Coordinates47.56203, -122.62517
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.
Channel and channel protection8 Very GoodNo problems noted.
Last inspectionMay 2023
Inspection intervalevery 24 months
Operating statusOpen, no restriction
ScourScour critical; foundations unstable for calculated scour conditions
Structural evaluation4: Meets minimum tolerable limits to be left in place as is
Deck geometry2: Basically intolerable, requiring high priority of replacement
Waterway adequacy8: Equal to present desirable criteria
Approach roadway alignment8: Equal to present desirable criteria
Operating rating30 US tons
Inventory rating18 US tons

Structure

Structure typeMovable - Lift
MaterialSteel
DeckClosed grating
Main spans1
Design loadHS 20
Structure length105 ft (32 m)
Longest span80 ft (24.4 m)
Deck width25 ft (7.6 m)
Roadway width20 ft (6.1 m)
Vertical clearance over deck16 ft (4.9 m)

Traffic and service

Average daily traffic3,600 (2010)
Projected traffic4,320 by 2031
Trucks1%
Lanes on structure2
Traffic directionOne-way traffic
CarriesHighway
CrossesWaterway
Detour if closed—
TollToll bridge
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$1.3 million (2022 estimate)
NavigationNo navigation control on waterway

Frequently asked questions

When was SR 304 over Sinclair Inlet built?

It was built in 1990, making it 35 years old in 2025.

What condition is SR 304 over Sinclair Inlet 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 May 2023.

How much traffic does SR 304 over Sinclair Inlet carry?

About 3,600 vehicles per day (2010 count), of which roughly 1% are trucks.

How long is SR 304 over Sinclair Inlet?

The structure is 105 ft (32 m) long with a longest span of 80 ft (24.4 m) and a deck 25 ft wide.

Who owns SR 304 over Sinclair Inlet?

It is owned by the State Highway Agency.