US Bridges

KACKMAN/4210 over Downing Creek

Good

Whitman County, Washington · 0.06 MI S Lancaster · Structure no. 084830000000000

Built
1979
46 years old
Condition
Good
inspected December 2023
Type
Tee Beam
Prestressed Concrete
Length
100 ft
1 main span
Daily traffic
20
2021 count
Owner
County
County Highway Agency

About this bridge

KACKMAN/4210 over Downing Creek is a prestressed concrete tee beam carrying KACKMAN/4210 over Downing Creek in Whitman County, Washington. It was built in 1979, so it is 46 years old, younger than the Washington average of 49.8 years.

The most recent inspection reported to the Federal Highway Administration rates it in good condition with a lowest component rating of 7 out of 9. All primary components (deck, superstructure, substructure, or culvert) are rated 7 or higher. No significant problems were noted.

It carries about 20 vehicles a day, roughly 25% of them trucks, projected to reach 21 by 2044. The structure is 100 ft (30.5 m) long and 26 ft wide. If it were closed, the detour would be 19.3 mi (31 km).

CarriesKACKMAN/4210
CrossesDowning Creek
Location0.06 MI S Lancaster
RouteCounty Highway 42100
Coordinates47.00408, -117.72435
Functional classRural Local

Condition and inspection

Good

All primary components (deck, superstructure, substructure, or culvert) are rated 7 or higher. No significant problems were noted.

ComponentRatingMeaning
Deck7 GoodSome minor problems.
Superstructure7 GoodSome minor problems.
Substructure7 GoodSome minor problems.
Channel and channel protection8 Very GoodNo problems noted.
Last inspectionDecember 2023
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 geometry2: Basically intolerable, requiring high priority of replacement
Waterway adequacy8: Equal to present desirable criteria
Approach roadway alignment6: Equal to present minimum criteria
Operating rating47.2 US tons
Inventory rating25 US tons

Structure

Structure typeTee Beam
MaterialPrestressed Concrete
DeckOther
Main spans1
Design loadHS 20
Structure length100 ft (30.5 m)
Longest span99 ft (30.2 m)
Deck width26 ft (7.9 m)
Roadway width24 ft (7.4 m)
Vertical clearance over deckUnrestricted

Traffic and service

Average daily traffic20 (2021)
Projected traffic21 by 2044
Trucks25%
Lanes on structure2
Traffic directionOne-way traffic
CarriesHighway
CrossesWaterway
Detour if closed19.3 mi (31 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$4 million (2022 estimate)
NavigationNo navigation control on waterway

Frequently asked questions

When was KACKMAN/4210 over Downing Creek built?

It was built in 1979, making it 46 years old in 2025.

What condition is KACKMAN/4210 over Downing Creek in?

The National Bridge Inventory rates it in good condition. All primary components (deck, superstructure, substructure, or culvert) are rated 7 or higher. No significant problems were noted. The last reported inspection was in December 2023.

How much traffic does KACKMAN/4210 over Downing Creek carry?

About 20 vehicles per day (2021 count), of which roughly 25% are trucks.

How long is KACKMAN/4210 over Downing Creek?

The structure is 100 ft (30.5 m) long with a longest span of 99 ft (30.2 m) and a deck 26 ft wide.

Who owns KACKMAN/4210 over Downing Creek?

It is owned by the County Highway Agency.