US Bridges

Seven Locks Road over Cabin John Creek

Fair

Montgomery County, Maryland · .1 MI S of Democracy Blvd · Structure no. 200000M-0143020

Built
1960
65 years old, rebuilt 1992
Condition
Fair
inspected February 2023
Type
Culvert
Concrete
Length
45 ft
Daily traffic
30,260
2021 count
Owner
County
County Highway Agency

About this bridge

Seven Locks Road over Cabin John Creek is a concrete culvert carrying Seven Locks Road over Cabin John Creek in Montgomery County, Maryland. It was built in 1960 and reconstructed in 1992, so it is 65 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 30,260 vehicles a day, roughly 5% of them trucks, projected to reach 36,695 by 2041. The structure is 45 ft (13.7 m) long. If it were closed, the detour would be 1.2 mi (2 km).

Location

Open in Google Maps
CarriesSeven Locks Road
CrossesCabin John Creek
Location.1 MI S of Democracy Blvd
RouteCounty Highway 148
CountyMontgomery County
StateMaryland
Coordinates39.02273, -77.16243
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
Channel and channel protection4 PoorAdvanced section loss, deterioration, spalling or scour.
Culvert5 FairAll primary structural elements are sound but may have minor section loss, cracking, spalling or scour.
Last inspectionFebruary 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 adequacy5: Somewhat better than minimum adequacy to tolerate being left in place as is
Approach roadway alignment8: Equal to present desirable criteria
Operating rating110.1 US tons
Inventory rating78.5 US tons

Structure

Structure typeCulvert
MaterialConcrete
DeckNot applicable
Main spans0
Design loadHS 20
Structure length45 ft (13.7 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 traffic30,260 (2021)
Projected traffic36,695 by 2041
Trucks5%
Lanes on structure5
Traffic directionTwo-way traffic
CarriesHighway and pedestrian
CrossesWaterway
Detour if closed1.2 mi (2 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 Seven Locks Road over Cabin John Creek built?

It was built in 1960, making it 65 years old in 2025. It was reconstructed in 1992.

What condition is Seven Locks Road over Cabin John 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 February 2023.

How much traffic does Seven Locks Road over Cabin John Creek carry?

About 30,260 vehicles per day (2021 count), of which roughly 5% are trucks.

How long is Seven Locks Road over Cabin John Creek?

The structure is 45 ft (13.7 m) long with a longest span of 14 ft (4.3 m).

Who owns Seven Locks Road over Cabin John Creek?

It is owned by the County Highway Agency.