US Bridges

Frntage Road 81020 over Miles Creek 037

PoorPosted for load

Custer County, Montana · 20M NE Miles City · Structure no. L09004004+06001

Built
1929
96 years old, rebuilt 1948
Condition
Poor
inspected September 2024
Type
Stringer/Multi-beam or Girder
Wood or Timber
Length
58 ft
3 main spans
Daily traffic
507
2023 count
Owner
State
State Highway Agency

About this bridge

Frntage Road 81020 over Miles Creek 037 is a wood or timber stringer/multi-beam or girder carrying Frntage Road 81020 over Miles Creek 037 in Custer County, Montana. It was built in 1929 and reconstructed in 1948, so it is 96 years old, older than the Montana average of 47 years.

The most recent inspection reported to the Federal Highway Administration rates it in poor condition with a lowest component rating of 4 out of 9. The lowest-rated primary component is rated 4 or below, indicating advanced deterioration. Poor does not mean unsafe; such bridges are inspected more often and may carry load restrictions. Its operating status is: posted for load restriction.

It carries about 507 vehicles a day, roughly 3% of them trucks, projected to reach 540 by 2043. The structure is 58 ft (17.8 m) long and 32 ft wide. If it were closed, the detour would be 1.2 mi (2 km).

CarriesFrntage Road 81020
CrossesMiles Creek 037
Location20M NE Miles City
RouteState Highway 81020
StateMontana
Coordinates46.62655, -105.54135
Functional classRural Local

Condition and inspection

Poor

The lowest-rated primary component is rated 4 or below, indicating advanced deterioration. Poor does not mean unsafe; such bridges are inspected more often and may carry load restrictions.

ComponentRatingMeaning
Deck7 GoodSome minor problems.
Superstructure4 PoorAdvanced section loss, deterioration, spalling or scour.
Substructure4 PoorAdvanced section loss, deterioration, spalling or scour.
Channel and channel protection5 FairAll primary structural elements are sound but may have minor section loss, cracking, spalling or scour.
Last inspectionSeptember 2024
Inspection intervalevery 24 months
Operating statusPosted for load restriction
ScourFoundations stable; scour above top of footing
Structural evaluation4: Meets minimum tolerable limits to be left in place as is
Deck geometry6: Equal to present minimum criteria
Waterway adequacy4: Meets minimum tolerable limits to be left in place as is
Approach roadway alignment8: Equal to present desirable criteria
Operating rating44 US tons
Inventory rating29 US tons

Structure

MaterialWood or Timber
DeckWood or timber
Main spans3
Design loadH 15
Structure length58 ft (17.8 m)
Longest span19 ft (5.8 m)
Deck width32 ft (9.8 m)
Roadway width30 ft (9.2 m)
Vertical clearance over deckUnrestricted

Traffic and service

Average daily traffic507 (2023)
Projected traffic540 by 2043
Trucks3%
Lanes on structure2
Traffic directionTwo-way traffic
CarriesHighway
CrossesWaterway
Detour if closed1.2 mi (2 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 Frntage Road 81020 over Miles Creek 037 built?

It was built in 1929, making it 96 years old in 2025. It was reconstructed in 1948.

What condition is Frntage Road 81020 over Miles Creek 037 in?

The National Bridge Inventory rates it in poor condition. The lowest-rated primary component is rated 4 or below, indicating advanced deterioration. Poor does not mean unsafe; such bridges are inspected more often and may carry load restrictions. The last reported inspection was in September 2024.

How much traffic does Frntage Road 81020 over Miles Creek 037 carry?

About 507 vehicles per day (2023 count), of which roughly 3% are trucks.

How long is Frntage Road 81020 over Miles Creek 037?

The structure is 58 ft (17.8 m) long with a longest span of 19 ft (5.8 m) and a deck 32 ft wide.

Who owns Frntage Road 81020 over Miles Creek 037?

It is owned by the State Highway Agency.