US Bridges

US 29 NB over Middle Patuxent River

Fair

Howard County, Maryland · 1.05 Miles South of Md 32 · Structure no. 100000130013011

Built
1951
74 years old, rebuilt 2001
Condition
Fair
inspected October 2023
Type
Stringer/Multi-beam or Girder
Steel Continuous
Length
134 ft
3 main spans
Daily traffic
52,913
2009 count
Owner
State
State Highway Agency

About this bridge

US 29 NB over Middle Patuxent River is a steel continuous stringer/multi-beam or girder carrying US 29 NB over Middle Patuxent River in Howard County, Maryland. It was built in 1951 and reconstructed in 2001, so it is 74 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 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 52,913 vehicles a day, roughly 8% of them trucks, projected to reach 31,442 by 2026. The structure is 134 ft (40.8 m) long and 56 ft wide. If it were closed, the detour would be 1.2 mi (2 km).

CarriesUS 29 NB
CrossesMiddle Patuxent River
Location1.05 Miles South of Md 32
RouteU.S. Route 29
Coordinates39.16822, -76.88426
Functional classUrban Principal Arterial - Other Freeway or Expressway

Condition and inspection

Fair

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

ComponentRatingMeaning
Deck6 SatisfactoryStructural elements show some minor deterioration.
Superstructure7 GoodSome minor problems.
Substructure6 SatisfactoryStructural elements show some minor deterioration.
Channel and channel protection8 Very GoodNo problems noted.
Last inspectionOctober 2023
Inspection intervalevery 24 months
Operating statusOpen, no restriction
ScourFoundations stable; scour within limits of footing or piles
Structural evaluation6: Equal to present minimum criteria
Deck geometry9: Superior to present desirable criteria
Waterway adequacy9: Superior to present desirable criteria
Approach roadway alignment8: Equal to present desirable criteria
Operating rating82 US tons
Inventory rating48.9 US tons

Structure

MaterialSteel Continuous
DeckConcrete, cast-in-place
Main spans3
Design loadHS 20
Structure length134 ft (40.8 m)
Longest span50 ft (15.2 m)
Deck width56 ft (17 m)
Roadway width52 ft (16 m)
Vertical clearance over deckUnrestricted

Traffic and service

Average daily traffic52,913 (2009)
Projected traffic31,442 by 2026
Trucks8%
Lanes on structure2
Traffic directionOne-way traffic
CarriesHighway and pedestrian
CrossesWaterway
Detour if closed1.2 mi (2 km)
TollOn a free road
National Highway SystemYes

Ownership and planned work

OwnerState Highway Agency
Maintained byState Highway Agency
Historic statusNot eligible for the National Register of Historic Places
Work proposedWidening of existing bridge without deck rehabilitation
Estimated improvement cost$330,000
NavigationNo navigation control on waterway

Frequently asked questions

When was US 29 NB over Middle Patuxent River built?

It was built in 1951, making it 74 years old in 2025. It was reconstructed in 2001.

What condition is US 29 NB over Middle Patuxent River 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 October 2023.

How much traffic does US 29 NB over Middle Patuxent River carry?

About 52,913 vehicles per day (2009 count), of which roughly 8% are trucks.

How long is US 29 NB over Middle Patuxent River?

The structure is 134 ft (40.8 m) long with a longest span of 50 ft (15.2 m) and a deck 56 ft wide.

Who owns US 29 NB over Middle Patuxent River?

It is owned by the State Highway Agency.