US Bridges

Mill Road over Helena Valley Canal 082

Good

Lewis and Clark County, Montana · 2M NW Helena · Structure no. 000000202104939

Built
2021
4 years old
Condition
Good
inspected November 2023
Type
Tee Beam
Prestressed Concrete
Length
49 ft
1 main span
Daily traffic
1,219
2023 count
Owner
County
County Highway Agency

About this bridge

Mill Road over Helena Valley Canal 082 is a prestressed concrete tee beam carrying Mill Road over Helena Valley Canal 082 in Lewis and Clark County, Montana. It was built in 2021, so it is 4 years old, younger than the Montana average of 47 years.

The most recent inspection reported to the Federal Highway Administration rates it in good condition with a lowest component rating of 8 out of 9. All primary components (deck, superstructure, substructure, or culvert) are rated 7 or higher. No significant problems were noted.

It carries about 1,219 vehicles a day, projected to reach 1,280 by 2043. The structure is 49 ft (14.8 m) long and 30 ft wide. If it were closed, the detour would be 3.1 mi (5 km).

Location

Open in Google Maps
CarriesMill Road
CrossesHelena Valley Canal 082
Location2M NW Helena
RouteCity Street 25058
CountyLewis and Clark County
StateMontana
Coordinates46.64566, -112.04644
Functional classUrban Collector

Condition and inspection

Good

All primary components (deck, superstructure, substructure, or culvert) are rated 7 or higher. No significant problems were noted.

ComponentRatingMeaning
Deck8 Very GoodNo problems noted.
Superstructure8 Very GoodNo problems noted.
Substructure8 Very GoodNo problems noted.
Channel and channel protection7 GoodSome minor problems.
Last inspectionNovember 2023
Inspection intervalevery 24 months
Operating statusOpen, no restriction
ScourFoundations stable; scour above top of footing
Structural evaluation8: Equal to present desirable criteria
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 rating61 US tons
Inventory rating42 US tons

Structure

Structure typeTee Beam
MaterialPrestressed Concrete
DeckConcrete, precast panels
Main spans1
Design loadHL 93
Structure length49 ft (14.8 m)
Longest span46 ft (14 m)
Deck width30 ft (9.2 m)
Roadway width28 ft (8.5 m)
Vertical clearance over deckUnrestricted

Traffic and service

Average daily traffic1,219 (2023)
Projected traffic1,280 by 2043
Trucks0%
Lanes on structure2
Traffic directionTwo-way traffic
CarriesHighway
CrossesWaterway
Detour if closed3.1 mi (5 km)
TollOn a free road
National Highway SystemNo

Ownership and planned work

OwnerCounty Highway Agency
Maintained byCounty 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 Mill Road over Helena Valley Canal 082 built?

It was built in 2021, making it 4 years old in 2025.

What condition is Mill Road over Helena Valley Canal 082 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 November 2023.

How much traffic does Mill Road over Helena Valley Canal 082 carry?

About 1,219 vehicles per day (2023 count).

How long is Mill Road over Helena Valley Canal 082?

The structure is 49 ft (14.8 m) long with a longest span of 46 ft (14 m) and a deck 30 ft wide.

Who owns Mill Road over Helena Valley Canal 082?

It is owned by the County Highway Agency.