US Bridges

Md 66 over Blackrock Creek

Fair

Washington County, Maryland · 0.27 Mile South of Is 70 · Structure no. 100000210132020

Built
1968
57 years old
Condition
Fair
inspected April 2023
Type
Culvert
Concrete
Length
50 ft
Daily traffic
5,291
2009 count
Owner
State
State Highway Agency

About this bridge

Md 66 over Blackrock Creek is a concrete culvert carrying Md 66 over Blackrock Creek in Washington County, Maryland. It was built in 1968, so it is 57 years old, older than the Maryland average of 52.6 years.

The most recent inspection reported to the Federal Highway Administration rates it in fair condition with a lowest component rating of 5 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 5,291 vehicles a day, roughly 8% of them trucks, projected to reach 7,691 by 2029. The structure is 50 ft (15.2 m) long. If it were closed, the detour would be 5 mi (8 km).

Location

Open in Google Maps
CarriesMd 66
CrossesBlackrock Creek
Location0.27 Mile South of Is 70
RouteState Highway 66
CountyWashington County
StateMaryland
Coordinates39.58259, -77.64254
Functional classRural Major Collector

Condition and inspection

Fair

The lowest-rated primary component is rated 5 or 6. Minor deterioration is present but the structure is sound.

ComponentRatingMeaning
Channel and channel protection6 SatisfactoryStructural elements show some minor deterioration.
Culvert5 FairAll primary structural elements are sound but may have minor section loss, cracking, spalling or scour.
Last inspectionApril 2023
Inspection intervalevery 24 months
Operating statusOpen, no restriction
ScourFoundations stable; scour above top of footing
Structural evaluation5: 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 rating36 US tons
Inventory rating36 US tons

Structure

Structure typeCulvert
MaterialConcrete
DeckNot applicable
Main spans0
Design loadHS 20
Structure length50 ft (15.2 m)
Longest span14 ft (4.3 m)
Deck width0 ft (0 m)
Roadway width0 ft (0 m)
Vertical clearance over deckUnrestricted

Traffic and service

Average daily traffic5,291 (2009)
Projected traffic7,691 by 2029
Trucks8%
Lanes on structure2
Traffic directionTwo-way traffic
CarriesHighway
CrossesWaterway
Detour if closed5 mi (8 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 Md 66 over Blackrock Creek built?

It was built in 1968, making it 57 years old in 2025.

What condition is Md 66 over Blackrock Creek 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 April 2023.

How much traffic does Md 66 over Blackrock Creek carry?

About 5,291 vehicles per day (2009 count), of which roughly 8% are trucks.

How long is Md 66 over Blackrock Creek?

The structure is 50 ft (15.2 m) long with a longest span of 14 ft (4.3 m).

Who owns Md 66 over Blackrock Creek?

It is owned by the State Highway Agency.