US Bridges

SH 12 Ml over S Fk Purgatoire River

Fair

Las Animas County, Colorado · At Weston · Structure no. P-17-J

Built
1936
89 years old, rebuilt 1970
Condition
Fair
inspected September 2024
Type
Stringer/Multi-beam or Girder
Steel Continuous
Length
72 ft
3 main spans
Daily traffic
520
2020 count
Owner
State
State Highway Agency

About this bridge

SH 12 Ml over S Fk Purgatoire River is a steel continuous stringer/multi-beam or girder carrying SH 12 Ml over S Fk Purgatoire River in Las Animas County, Colorado. It was built in 1936 and reconstructed in 1970, so it is 89 years old, older than the Colorado average of 42.2 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 520 vehicles a day, roughly 8% of them trucks, projected to reach 567 by 2040. The structure is 72 ft (21.9 m) long and 40 ft wide. If it were closed, the detour would be 98.8 mi (159 km).

CarriesSH 12 Ml
CrossesS Fk Purgatoire River
LocationAt Weston
RouteState Highway 12A
Coordinates37.12967, -104.84655
Functional classRural Major Collector

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.
Substructure7 GoodSome minor problems.
Channel and channel protection8 Very GoodNo problems noted.
Last inspectionSeptember 2024
Inspection intervalevery 24 months
Operating statusOpen, no restriction
ScourScour critical; foundations unstable for calculated scour conditions
Structural evaluation7: Better than present minimum criteria
Deck geometry7: Better than present minimum criteria
Waterway adequacy8: Equal to present desirable criteria
Approach roadway alignment8: Equal to present desirable criteria
Operating rating63.1 US tons
Inventory rating37 US tons

Structure

MaterialSteel Continuous
DeckConcrete, cast-in-place
Main spans3
Design loadHS 20 + Mod
Structure length72 ft (21.9 m)
Longest span23 ft (7 m)
Deck width40 ft (12.3 m)
Roadway width38 ft (11.6 m)
Vertical clearance over deckUnrestricted

Traffic and service

Average daily traffic520 (2020)
Projected traffic567 by 2040
Trucks8%
Lanes on structure2
Traffic directionTwo-way traffic
CarriesHighway
CrossesWaterway
Detour if closed98.8 mi (159 km)
TollOn a free road
National Highway SystemNo

Ownership and planned work

OwnerState Highway Agency
Maintained byState Highway Agency
Historic statusNot eligible for the National Register of Historic Places
Work proposedNone recorded
Estimated improvement cost—
NavigationNo navigation control on waterway

Frequently asked questions

When was SH 12 Ml over S Fk Purgatoire River built?

It was built in 1936, making it 89 years old in 2025. It was reconstructed in 1970.

What condition is SH 12 Ml over S Fk Purgatoire River 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 2024.

How much traffic does SH 12 Ml over S Fk Purgatoire River carry?

About 520 vehicles per day (2020 count), of which roughly 8% are trucks.

How long is SH 12 Ml over S Fk Purgatoire River?

The structure is 72 ft (21.9 m) long with a longest span of 23 ft (7 m) and a deck 40 ft wide.

Who owns SH 12 Ml over S Fk Purgatoire River?

It is owned by the State Highway Agency.