US Bridges

Ballfield Road over Tibbets Creek

Fair

King County, Washington · 0.1 MI E of SR-900 · Structure no. 086469000000000

Built
1975
50 years old
Condition
Fair
inspected September 2023
Type
Stringer/Multi-beam or Girder
Wood or Timber
Length
23 ft
1 main span
Daily traffic
20
2021 count
Owner
City
City or Municipal Highway Agency

About this bridge

Ballfield Road over Tibbets Creek is a wood or timber stringer/multi-beam or girder carrying Ballfield Road over Tibbets Creek in King County, Washington. It was built in 1975, so it is 50 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 20 vehicles a day, roughly 20% of them trucks, projected to reach 30 by 2041. The structure is 23 ft (7 m) long and 12 ft wide. If it were closed, the detour would be 98.8 mi (159 km).

Location

Open in Google Maps
CarriesBallfield Road
CrossesTibbets Creek
Location0.1 MI E of SR-900
RouteCity Street 590
CountyKing County
StateWashington
Coordinates47.53881, -122.06175
Functional classUrban 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
Deck6 SatisfactoryStructural elements show some minor deterioration.
Superstructure7 GoodSome minor problems.
Substructure6 SatisfactoryStructural elements show some minor deterioration.
Channel and channel protection6 SatisfactoryStructural elements show some minor deterioration.
Last inspectionSeptember 2023
Inspection intervalevery 24 months
Operating statusOpen, no restriction
ScourUnknown foundation; not evaluated for scour
Structural evaluation5: Somewhat better than minimum adequacy to tolerate being left in place as is
Deck geometry2: Basically intolerable, requiring high priority of replacement
Waterway adequacy6: Equal to present minimum criteria
Approach roadway alignment8: Equal to present desirable criteria
Operating rating36 US tons
Inventory rating19 US tons

Structure

Structure typeStringer/Multi-beam or Girder
MaterialWood or Timber
DeckWood or timber
Main spans1
Design loadHS 20
Structure length23 ft (7 m)
Longest span21 ft (6.4 m)
Deck width12 ft (3.7 m)
Roadway width10 ft (3 m)
Vertical clearance over deckUnrestricted

Traffic and service

Average daily traffic20 (2021)
Projected traffic30 by 2041
Trucks20%
Lanes on structure1
Traffic directionOne-lane bridge for two-way traffic
CarriesHighway and pedestrian
CrossesWaterway
Detour if closed98.8 mi (159 km)
TollOn a free road
National Highway SystemNo

Ownership and planned work

OwnerCity or Municipal Highway Agency
Maintained byCity or Municipal Highway Agency
Historic statusHistorical significance not determinable at this time
Work proposedReplacement because of substandard load-carrying capacity or roadway geometry
Estimated improvement cost$686,000 (2017 estimate)
NavigationNo navigation control on waterway

Frequently asked questions

When was Ballfield Road over Tibbets Creek built?

It was built in 1975, making it 50 years old in 2025.

What condition is Ballfield Road over Tibbets 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 September 2023.

How much traffic does Ballfield Road over Tibbets Creek carry?

About 20 vehicles per day (2021 count), of which roughly 20% are trucks.

How long is Ballfield Road over Tibbets Creek?

The structure is 23 ft (7 m) long with a longest span of 21 ft (6.4 m) and a deck 12 ft wide.

Who owns Ballfield Road over Tibbets Creek?

It is owned by the City or Municipal Highway Agency.