US Bridges

SH 157 Ml over BNSF RR

Fair

Boulder County, Colorado · In Boulder · Structure no. D-16-CV

Built
1981
44 years old
Condition
Fair
inspected July 2023
Type
Box Beam or Girders - Single or Spread
Prestressed Concrete Continuous
Length
185 ft
3 main spans
Daily traffic
43,000
2020 count
Owner
State
State Highway Agency

About this bridge

SH 157 Ml over BNSF RR is a prestressed concrete continuous box beam or girders - single or spread carrying SH 157 Ml over BNSF RR in Boulder County, Colorado. It was built in 1981, so it is 44 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 43,000 vehicles a day, roughly 4% of them trucks, projected to reach 46,440 by 2040. The structure is 185 ft (56.5 m) long and 115 ft wide. If it were closed, the detour would be 1.9 mi (3 km).

Location

Open in Google Maps
CarriesSH 157 Ml
CrossesBNSF RR
LocationIn Boulder
RouteState Highway 157A
CountyBoulder County
StateColorado
Coordinates40.02033, -105.24413
Functional classUrban Principal Arterial - Other Freeway or Expressway

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.
Last inspectionJuly 2023
Inspection intervalevery 24 months
Operating statusOpen, no restriction
ScourBridge not over waterway
Structural evaluation3: Basically intolerable, requiring high priority of corrective action
Deck geometry9: Superior to present desirable criteria
Approach roadway alignment8: Equal to present desirable criteria
Operating rating39.2 US tons
Inventory rating12 US tons

Structure

Structure typeBox Beam or Girders - Single or Spread
MaterialPrestressed Concrete Continuous
DeckConcrete, cast-in-place
Main spans3
Design loadHS 20 + Mod
Structure length185 ft (56.5 m)
Longest span77 ft (23.6 m)
Deck width115 ft (35.1 m)
Roadway width102 ft (31.1 m)
Vertical clearance over deckUnrestricted

Traffic and service

Average daily traffic43,000 (2020)
Projected traffic46,440 by 2040
Trucks4%
Lanes on structure6
Traffic directionTwo-way traffic
CarriesHighway and pedestrian
CrossesRailroad
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 proposedWidening of existing bridge without deck rehabilitation
Estimated improvement cost$1.6 million (2017 estimate)
NavigationNo navigation control on waterway

Frequently asked questions

When was SH 157 Ml over BNSF RR built?

It was built in 1981, making it 44 years old in 2025.

What condition is SH 157 Ml over BNSF RR 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 July 2023.

How much traffic does SH 157 Ml over BNSF RR carry?

About 43,000 vehicles per day (2020 count), of which roughly 4% are trucks.

How long is SH 157 Ml over BNSF RR?

The structure is 185 ft (56.5 m) long with a longest span of 77 ft (23.6 m) and a deck 115 ft wide.

Who owns SH 157 Ml over BNSF RR?

It is owned by the State Highway Agency.