US Bridges

Oaklyn Drive over Rock Run

Fair

Montgomery County, Maryland · 1 Miles South of Md 189 · Structure no. 200000M-0012010

Built
1989
36 years old
Condition
Fair
inspected December 2024
Type
Slab
Concrete Continuous
Length
48 ft
2 main spans
Daily traffic
4,934
2024 count
Owner
County
County Highway Agency

About this bridge

Oaklyn Drive over Rock Run is a concrete continuous slab carrying Oaklyn Drive over Rock Run in Montgomery County, Maryland. It was built in 1989, so it is 36 years old, younger 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 6 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 4,934 vehicles a day, roughly 5% of them trucks, projected to reach 6,645 by 2044. The structure is 48 ft (14.6 m) long and 47 ft wide. If it were closed, the detour would be 1.9 mi (3 km).

Location

Open in Google Maps
CarriesOaklyn Drive
CrossesRock Run
Location1 Miles South of Md 189
RouteCounty Highway 189
CountyMontgomery County
StateMaryland
Coordinates39.00373, -77.21427
Functional classUrban Local

Condition and inspection

Fair

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

ComponentRatingMeaning
Deck7 GoodSome minor problems.
Superstructure7 GoodSome minor problems.
Substructure6 SatisfactoryStructural elements show some minor deterioration.
Channel and channel protection6 SatisfactoryStructural elements show some minor deterioration.
Last inspectionDecember 2024
Inspection intervalevery 24 months
Operating statusOpen, no restriction
ScourFoundations stable; scour above top of footing
Structural evaluation6: Equal to present minimum criteria
Deck geometry7: Better than present minimum criteria
Waterway adequacy6: Equal to present minimum criteria
Approach roadway alignment8: Equal to present desirable criteria
Operating rating91.5 US tons
Inventory rating54.5 US tons

Structure

Structure typeSlab
MaterialConcrete Continuous
DeckConcrete, cast-in-place
Main spans2
Design loadHS 20
Structure length48 ft (14.6 m)
Longest span23 ft (7 m)
Deck width47 ft (14.4 m)
Roadway width44 ft (13.4 m)
Vertical clearance over deckUnrestricted

Traffic and service

Average daily traffic4,934 (2024)
Projected traffic6,645 by 2044
Trucks5%
Lanes on structure2
Traffic directionTwo-way traffic
CarriesHighway
CrossesWaterway
Detour if closed1.9 mi (3 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 Oaklyn Drive over Rock Run built?

It was built in 1989, making it 36 years old in 2025.

What condition is Oaklyn Drive over Rock Run 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 December 2024.

How much traffic does Oaklyn Drive over Rock Run carry?

About 4,934 vehicles per day (2024 count), of which roughly 5% are trucks.

How long is Oaklyn Drive over Rock Run?

The structure is 48 ft (14.6 m) long with a longest span of 23 ft (7 m) and a deck 47 ft wide.

Who owns Oaklyn Drive over Rock Run?

It is owned by the County Highway Agency.