US Bridges

Miller Hm PLC/3920 over Negro Creek

FairPosted for load

Whitman County, Washington · 0.55 MI S Belsby · Structure no. 080960000000000

Built
1913
112 years old, rebuilt 1957
Condition
Fair
inspected November 2024
Type
Stringer/Multi-beam or Girder
Wood or Timber
Length
24 ft
1 main span
Daily traffic
5
2022 count
Owner
County
County Highway Agency

About this bridge

Miller Hm PLC/3920 over Negro Creek is a wood or timber stringer/multi-beam or girder carrying Miller Hm PLC/3920 over Negro Creek in Whitman County, Washington. It was built in 1913 and reconstructed in 1957, so it is 112 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 5 out of 9. The lowest-rated primary component is rated 5 or 6. Minor deterioration is present but the structure is sound. Its operating status is: posted for load restriction.

It carries about 5 vehicles a day, roughly 20% of them trucks, projected to reach 6 by 2042. The structure is 24 ft (7.3 m) long and 20 ft wide. If it were closed, the detour would be 14.9 mi (24 km).

CarriesMiller Hm PLC/3920
CrossesNegro Creek
Location0.55 MI S Belsby
RouteCounty Highway 39200
Coordinates47.24683, -117.65947
Functional classRural Local

Condition and inspection

Fair

The lowest-rated primary component is rated 5 or 6. Minor deterioration is present but the structure is sound.

ComponentRatingMeaning
Deck5 FairAll primary structural elements are sound but may have minor section loss, cracking, spalling or scour.
Superstructure6 SatisfactoryStructural elements show some minor deterioration.
Substructure6 SatisfactoryStructural elements show some minor deterioration.
Channel and channel protection8 Very GoodNo problems noted.
Last inspectionNovember 2024
Inspection intervalevery 12 months
Operating statusPosted for load restriction
ScourScour critical; foundations unstable for calculated scour conditions
Structural evaluation5: Somewhat better than minimum adequacy to tolerate being left in place as is
Deck geometry5: Somewhat better than minimum adequacy to tolerate being left in place as is
Waterway adequacy7: Better than present minimum criteria
Approach roadway alignment3: Basically intolerable, requiring high priority of corrective action
Operating rating29 US tons
Inventory rating20.9 US tons

Structure

MaterialWood or Timber
DeckWood or timber
Main spans1
Design loadH 15
Structure length24 ft (7.3 m)
Longest span23 ft (7 m)
Deck width20 ft (6.1 m)
Roadway width20 ft (6.1 m)
Vertical clearance over deckUnrestricted

Traffic and service

Average daily traffic5 (2022)
Projected traffic6 by 2042
Trucks20%
Lanes on structure2
Traffic directionTwo-way traffic
CarriesHighway
CrossesWaterway
Detour if closed14.9 mi (24 km)
TollOn a free road
National Highway SystemNo

Ownership and planned work

OwnerCounty Highway Agency
Maintained byCounty Highway Agency
Historic statusNot eligible for the National Register of Historic Places
Work proposedReplacement because of substandard load-carrying capacity or roadway geometry
Estimated improvement cost$1.2 million (2022 estimate)
NavigationNo navigation control on waterway

Frequently asked questions

When was Miller Hm PLC/3920 over Negro Creek built?

It was built in 1913, making it 112 years old in 2025. It was reconstructed in 1957.

What condition is Miller Hm PLC/3920 over Negro Creek 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 November 2024.

How much traffic does Miller Hm PLC/3920 over Negro Creek carry?

About 5 vehicles per day (2022 count), of which roughly 20% are trucks.

How long is Miller Hm PLC/3920 over Negro Creek?

The structure is 24 ft (7.3 m) long with a longest span of 23 ft (7 m) and a deck 20 ft wide.

Who owns Miller Hm PLC/3920 over Negro Creek?

It is owned by the County Highway Agency.