US Bridges

Agate Loop RD over Campbell Creek

Poor

Mason County, Washington · 0.48 N JCT Crestview DR · Structure no. 081698000000000

Built
1950
75 years old, rebuilt 1968
Condition
Poor
inspected July 2023
Type
Slab
Wood or Timber
Length
92 ft
6 main spans
Daily traffic
257
2020 count
Owner
County
County Highway Agency

About this bridge

Agate Loop RD over Campbell Creek is a wood or timber slab carrying Agate Loop RD over Campbell Creek in Mason County, Washington. It was built in 1950 and reconstructed in 1968, so it is 75 years old, older than the Washington average of 49.8 years.

The most recent inspection reported to the Federal Highway Administration rates it in poor condition with a lowest component rating of 4 out of 9. The lowest-rated primary component is rated 4 or below, indicating advanced deterioration. Poor does not mean unsafe; such bridges are inspected more often and may carry load restrictions.

It carries about 257 vehicles a day, roughly 5% of them trucks, projected to reach 500 by 2044. The structure is 92 ft (28 m) long and 28 ft wide. If it were closed, the detour would be 3.7 mi (6 km).

CarriesAgate Loop RD
CrossesCampbell Creek
Location0.48 N JCT Crestview DR
RouteCounty Highway 23500
Coordinates47.22167, -123.02833
Functional classRural Local

Condition and inspection

Poor

The lowest-rated primary component is rated 4 or below, indicating advanced deterioration. Poor does not mean unsafe; such bridges are inspected more often and may carry load restrictions.

ComponentRatingMeaning
Deck6 SatisfactoryStructural elements show some minor deterioration.
Superstructure4 PoorAdvanced section loss, deterioration, spalling or scour.
Substructure6 SatisfactoryStructural elements show some minor deterioration.
Channel and channel protection8 Very GoodNo problems noted.
Last inspectionJuly 2023
Inspection intervalevery 24 months
Operating statusOpen, no restriction
ScourUnknown foundation; not evaluated for scour
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 rating34 US tons
Inventory rating26 US tons

Structure

Structure typeSlab
MaterialWood or Timber
DeckWood or timber
Main spans6
Design loadHS 15
Structure length92 ft (28 m)
Longest span16 ft (4.8 m)
Deck width28 ft (8.5 m)
Roadway width24 ft (7.4 m)
Vertical clearance over deckUnrestricted

Traffic and service

Average daily traffic257 (2020)
Projected traffic500 by 2044
Trucks5%
Lanes on structure2
Traffic directionTwo-way traffic
CarriesHighway
CrossesWaterway
Detour if closed3.7 mi (6 km)
TollOn a free road
National Highway SystemNo

Ownership and planned work

OwnerCounty Highway Agency
Maintained byCounty Highway Agency
Historic statusHistorical significance not determinable at this time
Work proposedReplacement because of substandard load-carrying capacity or roadway geometry
Estimated improvement cost$3.1 million (2025 estimate)
NavigationNo navigation control on waterway

Frequently asked questions

When was Agate Loop RD over Campbell Creek built?

It was built in 1950, making it 75 years old in 2025. It was reconstructed in 1968.

What condition is Agate Loop RD over Campbell Creek in?

The National Bridge Inventory rates it in poor condition. The lowest-rated primary component is rated 4 or below, indicating advanced deterioration. Poor does not mean unsafe; such bridges are inspected more often and may carry load restrictions. The last reported inspection was in July 2023.

How much traffic does Agate Loop RD over Campbell Creek carry?

About 257 vehicles per day (2020 count), of which roughly 5% are trucks.

How long is Agate Loop RD over Campbell Creek?

The structure is 92 ft (28 m) long with a longest span of 16 ft (4.8 m) and a deck 28 ft wide.

Who owns Agate Loop RD over Campbell Creek?

It is owned by the County Highway Agency.