US Bridges

Mountain RD over Blackstone Brook

Good

Piscataquis County, Maine · 1.2MI W Shrly/Abbot RD · Structure no. 0940

Built
1945
80 years old, rebuilt 2023
Condition
Good
inspected May 2024
Type
Stringer/Multi-beam or Girder
Steel
Length
42 ft
1 main span
Daily traffic
10
2016 count
Owner
County
County Highway Agency

About this bridge

Mountain RD over Blackstone Brook is a steel stringer/multi-beam or girder carrying Mountain RD over Blackstone Brook in Piscataquis County, Maine. It was built in 1945 and reconstructed in 2023, so it is 80 years old, older than the Maine average of 53.7 years.

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

It carries about 10 vehicles a day, roughly 5% of them trucks, projected to reach 16 by 2036. The structure is 42 ft (12.8 m) long and 15 ft wide. If it were closed, the detour would be 6.2 mi (10 km).

CarriesMountain RD
CrossesBlackstone Brook
Location1.2MI W Shrly/Abbot RD
RouteCity Street 0
StateMaine
Coordinates45.25667, -69.60397
Functional classRural Local

Condition and inspection

Good

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

ComponentRatingMeaning
Deck9 ExcellentNo problems noted.
Superstructure9 ExcellentNo problems noted.
Substructure9 ExcellentNo problems noted.
Channel and channel protection8 Very GoodNo problems noted.
Last inspectionMay 2024
Inspection intervalevery 24 months
Operating statusOpen, no restriction
ScourScour critical; foundations unstable for calculated scour conditions
Structural evaluation9: Superior to present desirable criteria
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 rating65.4 US tons
Inventory rating50.4 US tons

Structure

MaterialSteel
DeckConcrete, precast panels
Main spans1
Design loadGreater than HL 93
Structure length42 ft (12.8 m)
Longest span39 ft (11.9 m)
Deck width15 ft (4.6 m)
Roadway width14 ft (4.4 m)
Vertical clearance over deckUnrestricted

Traffic and service

Average daily traffic10 (2016)
Projected traffic16 by 2036
Trucks5%
Lanes on structure1
Traffic directionOne-lane bridge for two-way traffic
CarriesHighway
CrossesWaterway
Detour if closed6.2 mi (10 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 Mountain RD over Blackstone Brook built?

It was built in 1945, making it 80 years old in 2025. It was reconstructed in 2023.

What condition is Mountain RD over Blackstone Brook 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 May 2024.

How much traffic does Mountain RD over Blackstone Brook carry?

About 10 vehicles per day (2016 count), of which roughly 5% are trucks.

How long is Mountain RD over Blackstone Brook?

The structure is 42 ft (12.8 m) long with a longest span of 39 ft (11.9 m) and a deck 15 ft wide.

Who owns Mountain RD over Blackstone Brook?

It is owned by the County Highway Agency.