US Bridges

US 12 over Cmstpp RR

Good

Thurston County, Washington · 7.7 E Grays Hbr CO · Structure no. 0017998A0000000

Built
2011
14 years old
Condition
Good
inspected November 2021
Type
Stringer/Multi-beam or Girder
Prestressed Concrete
Length
84 ft
1 main span
Daily traffic
23,512
2023 count
Owner
State
State Highway Agency

About this bridge

US 12 over Cmstpp RR is a prestressed concrete stringer/multi-beam or girder carrying US 12 over Cmstpp RR in Thurston County, Washington. It was built in 2011, so it is 14 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 8 out of 9. All primary components (deck, superstructure, substructure, or culvert) are rated 7 or higher. No significant problems were noted.

It carries about 23,512 vehicles a day, roughly 9% of them trucks, projected to reach 35,142 by 2039. The structure is 84 ft (25.6 m) long and 98 ft wide. If it were closed, the detour would be 8.1 mi (13 km).

Location

Open in Google Maps
CarriesUS 12
CrossesCmstpp RR
Location7.7 E Grays Hbr CO
RouteU.S. Route 12
CountyThurston County
StateWashington
Coordinates46.80264, -123.00891
Functional classUrban Principal Arterial - Other Freeway or Expressway

Condition and inspection

Good

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

ComponentRatingMeaning
Deck8 Very GoodNo problems noted.
Superstructure8 Very GoodNo problems noted.
Substructure8 Very GoodNo problems noted.
Last inspectionNovember 2021
Inspection intervalevery 48 months
Operating statusOpen, no restriction
ScourBridge not over waterway
Structural evaluation8: Equal to present desirable criteria
Deck geometry7: Better than present minimum criteria
Approach roadway alignment8: Equal to present desirable criteria
Operating rating89.9 US tons
Inventory rating54 US tons

Structure

Structure typeStringer/Multi-beam or Girder
MaterialPrestressed Concrete
DeckConcrete, cast-in-place
Main spans1
Design loadHL 93
Structure length84 ft (25.6 m)
Longest span80 ft (24.4 m)
Deck width98 ft (29.9 m)
Roadway width83 ft (25.3 m)
Vertical clearance over deckUnrestricted

Traffic and service

Average daily traffic23,512 (2023)
Projected traffic35,142 by 2039
Trucks9%
Lanes on structure5
Traffic directionTwo-way traffic
CarriesHighway and pedestrian
CrossesRailroad
Detour if closed8.1 mi (13 km)
TollOn a free road
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$3.4 million (2022 estimate)
NavigationNot applicable (no waterway)

Frequently asked questions

When was US 12 over Cmstpp RR built?

It was built in 2011, making it 14 years old in 2025.

What condition is US 12 over Cmstpp RR 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 November 2021.

How much traffic does US 12 over Cmstpp RR carry?

About 23,512 vehicles per day (2023 count), of which roughly 9% are trucks.

How long is US 12 over Cmstpp RR?

The structure is 84 ft (25.6 m) long with a longest span of 80 ft (24.4 m) and a deck 98 ft wide.

Who owns US 12 over Cmstpp RR?

It is owned by the State Highway Agency.