US Bridges

Irr# US 84 Ml over Rio Blanco

Fair

Archuleta County, Colorado · 16.7 MI N of New Mexico · Structure no. P-09-L

Built
1948
77 years old
Condition
Fair
inspected May 2023
Type
Truss - Thru
Steel
Length
130 ft
1 main span
Daily traffic
1,300
2020 count
Owner
State
State Highway Agency

About this bridge

Irr# US 84 Ml over Rio Blanco is a steel truss - thru carrying Irr# US 84 Ml over Rio Blanco in Archuleta County, Colorado. It was built in 1948, so it is 77 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 5 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 1,300 vehicles a day, roughly 7% of them trucks, projected to reach 1,352 by 2040. The structure is 130 ft (39.6 m) long and 31 ft wide. If it were closed, the detour would be 11.2 mi (18 km).

Location

Open in Google Maps
CarriesIrr# US 84 Ml
CrossesRio Blanco
Location16.7 MI N of New Mexico
RouteU.S. Route 84A
CountyArchuleta County
StateColorado
Coordinates37.14205, -106.92362
Functional classRural Minor Arterial

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.
Superstructure5 FairAll primary structural elements are sound but may have minor section loss, cracking, spalling or scour.
Substructure6 SatisfactoryStructural elements show some minor deterioration.
Channel and channel protection6 SatisfactoryStructural elements show some minor deterioration.
Last inspectionMay 2023
Inspection intervalevery 24 months
Operating statusOpen, no restriction
ScourFoundations stable; scour above top of footing
Structural evaluation4: Meets minimum tolerable limits to be left in place as is
Deck geometry5: Somewhat better than minimum adequacy to tolerate being left in place as is
Waterway adequacy8: Equal to present desirable criteria
Approach roadway alignment8: Equal to present desirable criteria
Operating rating28 US tons
Inventory rating16.8 US tons

Structure

Structure typeTruss - Thru
MaterialSteel
DeckConcrete, cast-in-place
Main spans1
Design loadUnknown
Structure length130 ft (39.6 m)
Longest span125 ft (38 m)
Deck width31 ft (9.6 m)
Roadway width30 ft (9.1 m)
Vertical clearance over deckUnrestricted

Traffic and service

Average daily traffic1,300 (2020)
Projected traffic1,352 by 2040
Trucks7%
Lanes on structure2
Traffic directionTwo-way traffic
CarriesHighway
CrossesWaterway
Detour if closed11.2 mi (18 km)
TollOn a free road
National Highway SystemNo

Ownership and planned work

OwnerState Highway Agency
Maintained byState Highway Agency
Historic statusPossibly eligible for the National Register; requires further investigation
Work proposedNone recorded
Estimated improvement cost$221,000
NavigationNo navigation control on waterway

Frequently asked questions

When was Irr# US 84 Ml over Rio Blanco built?

It was built in 1948, making it 77 years old in 2025.

What condition is Irr# US 84 Ml over Rio Blanco 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 May 2023.

How much traffic does Irr# US 84 Ml over Rio Blanco carry?

About 1,300 vehicles per day (2020 count), of which roughly 7% are trucks.

How long is Irr# US 84 Ml over Rio Blanco?

The structure is 130 ft (39.6 m) long with a longest span of 125 ft (38 m) and a deck 31 ft wide.

Who owns Irr# US 84 Ml over Rio Blanco?

It is owned by the State Highway Agency.