US Bridges

US 36 Ml over Flat Iron Circle East

Good

Broomfield County, Colorado · Near Flatirons Crossing · Structure no. E-16-IB

Built
1999
26 years old, rebuilt 2013
Condition
Good
inspected July 2023
Type
Stringer/Multi-beam or Girder
Prestressed Concrete Continuous
Length
213 ft
3 main spans
Daily traffic
62,000
2020 count
Owner
State
State Highway Agency

About this bridge

US 36 Ml over Flat Iron Circle East is a prestressed concrete continuous stringer/multi-beam or girder carrying US 36 Ml over Flat Iron Circle East in Broomfield County, Colorado. It was built in 1999 and reconstructed in 2013, so it is 26 years old, younger than the Colorado average of 42.2 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 62,000 vehicles a day, roughly 2% of them trucks, projected to reach 71,920 by 2040. The structure is 213 ft (65 m) long and 218 ft wide. If it were closed, the detour would be 1.9 mi (3 km).

CarriesUS 36 Ml
CrossesFlat Iron Circle East
LocationNear Flatirons Crossing
RouteU.S. Route 36B
Coordinates39.93222, -105.12229
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
Deck7 GoodSome minor problems.
Superstructure8 Very GoodNo problems noted.
Substructure7 GoodSome minor problems.
Last inspectionJuly 2023
Inspection intervalevery 24 months
Operating statusOpen, no restriction
ScourBridge not over waterway
Structural evaluation7: Better than present minimum criteria
Deck geometry9: Superior to present desirable criteria
Approach roadway alignment8: Equal to present desirable criteria
Operating rating60.5 US tons
Inventory rating36.2 US tons

Structure

MaterialPrestressed Concrete Continuous
DeckConcrete, cast-in-place
Main spans3
Design loadHS 25 or greater
Structure length213 ft (65 m)
Longest span87 ft (26.4 m)
Deck width218 ft (66.5 m)
Roadway width173 ft (52.8 m)
Vertical clearance over deckUnrestricted

Traffic and service

Average daily traffic62,000 (2020)
Projected traffic71,920 by 2040
Trucks2%
Lanes on structure8
Traffic directionTwo-way traffic
CarriesHighway
CrossesHighway
Detour if closed1.9 mi (3 km)
TollOn a free road
National Highway SystemYes

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 US 36 Ml over Flat Iron Circle East built?

It was built in 1999, making it 26 years old in 2025. It was reconstructed in 2013.

What condition is US 36 Ml over Flat Iron Circle East 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 July 2023.

How much traffic does US 36 Ml over Flat Iron Circle East carry?

About 62,000 vehicles per day (2020 count), of which roughly 2% are trucks.

How long is US 36 Ml over Flat Iron Circle East?

The structure is 213 ft (65 m) long with a longest span of 87 ft (26.4 m) and a deck 218 ft wide.

Who owns US 36 Ml over Flat Iron Circle East?

It is owned by the State Highway Agency.