US Bridges

Md 547 over Rock Creek

Fair

Montgomery County, Maryland · 0.66 Mile West of Md 185 · Structure no. 100000150062010

Built
1932
93 years old
Condition
Fair
inspected June 2023
Type
Tee Beam
Concrete
Length
52 ft
1 main span
Daily traffic
10,982
2009 count
Owner
State
State Highway Agency

About this bridge

Md 547 over Rock Creek is a concrete tee beam carrying Md 547 over Rock Creek in Montgomery County, Maryland. It was built in 1932, so it is 93 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 10,982 vehicles a day, roughly 8% of them trucks, projected to reach 13,296 by 2026. The structure is 52 ft (15.9 m) long and 35 ft wide. If it were closed, the detour would be 5 mi (8 km).

Location

Open in Google Maps
CarriesMd 547
CrossesRock Creek
Location0.66 Mile West of Md 185
RouteState Highway 547
CountyMontgomery County
StateMaryland
Coordinates39.03174, -77.08737
Functional classUrban Minor Arterial

Condition and inspection

Fair

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

ComponentRatingMeaning
Deck5 FairAll primary structural elements are sound but may have minor section loss, cracking, spalling or scour.
Superstructure6 SatisfactoryStructural elements show some minor deterioration.
Substructure5 FairAll primary structural elements are sound but may have minor section loss, cracking, spalling or scour.
Channel and channel protection8 Very GoodNo problems noted.
Last inspectionJune 2023
Inspection intervalevery 24 months
Operating statusOpen, no restriction
ScourFoundations stable; scour within limits of footing or piles
Structural evaluation5: Somewhat better than minimum adequacy to tolerate being left in place as is
Deck geometry2: Basically intolerable, requiring high priority of replacement
Waterway adequacy9: Superior to present desirable criteria
Approach roadway alignment8: Equal to present desirable criteria
Operating rating64.5 US tons
Inventory rating39 US tons

Structure

Structure typeTee Beam
MaterialConcrete
DeckConcrete, cast-in-place
Main spans1
Design loadH 20
Structure length52 ft (15.9 m)
Longest span48 ft (14.6 m)
Deck width35 ft (10.7 m)
Roadway width27 ft (8.2 m)
Vertical clearance over deckUnrestricted

Traffic and service

Average daily traffic10,982 (2009)
Projected traffic13,296 by 2026
Trucks8%
Lanes on structure2
Traffic directionTwo-way traffic
CarriesHighway and pedestrian
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 statusPossibly eligible for the National Register; requires further investigation
Work proposedWidening of existing bridge without deck rehabilitation
Estimated improvement cost$120,000
NavigationNo navigation control on waterway

Frequently asked questions

When was Md 547 over Rock Creek built?

It was built in 1932, making it 93 years old in 2025.

What condition is Md 547 over Rock 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 June 2023.

How much traffic does Md 547 over Rock Creek carry?

About 10,982 vehicles per day (2009 count), of which roughly 8% are trucks.

How long is Md 547 over Rock Creek?

The structure is 52 ft (15.9 m) long with a longest span of 48 ft (14.6 m) and a deck 35 ft wide.

Who owns Md 547 over Rock Creek?

It is owned by the State Highway Agency.