US Bridges

Mannasota Avenue over Herring Run

Fair

Baltimore city, Maryland · 0.6 MI W Erdman Ave · Structure no. 200000BC4502010

Built
1928
97 years old
Condition
Fair
inspected October 2024
Type
Arch - Deck
Concrete
Length
56 ft
1 main span
Daily traffic
2,933
2020 count
Owner
City
City or Municipal Highway Agency

About this bridge

Mannasota Avenue over Herring Run is a concrete arch - deck carrying Mannasota Avenue over Herring Run in Baltimore city, Maryland. It was built in 1928, so it is 97 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 2,933 vehicles a day, roughly 5% of them trucks, projected to reach 3,940 by 2040. The structure is 56 ft (17.1 m) long and 49 ft wide. If it were closed, the detour would be 1.9 mi (3 km).

Location

Open in Google Maps
CarriesMannasota Avenue
CrossesHerring Run
Location0.6 MI W Erdman Ave
RouteCity Street 2485
CountyBaltimore city
StateMaryland
Coordinates39.32466, -76.56266
Functional classUrban 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
Superstructure6 SatisfactoryStructural elements show some minor deterioration.
Substructure6 SatisfactoryStructural elements show some minor deterioration.
Channel and channel protection5 FairAll primary structural elements are sound but may have minor section loss, cracking, spalling or scour.
Last inspectionOctober 2024
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 geometry4: Meets minimum tolerable limits to be left in place as is
Waterway adequacy9: Superior to present desirable criteria
Approach roadway alignment8: Equal to present desirable criteria
Operating rating91.9 US tons
Inventory rating55 US tons

Structure

Structure typeArch - Deck
MaterialConcrete
DeckNot applicable
Main spans1
Design loadH 20
Structure length56 ft (17.1 m)
Longest span52 ft (15.9 m)
Deck width49 ft (14.8 m)
Roadway width30 ft (9.2 m)
Vertical clearance over deckUnrestricted

Traffic and service

Average daily traffic2,933 (2020)
Projected traffic3,940 by 2040
Trucks5%
Lanes on structure2
Traffic directionTwo-way traffic
CarriesHighway and pedestrian
CrossesWaterway
Detour if closed1.9 mi (3 km)
TollOn a free road
National Highway SystemNo

Ownership and planned work

OwnerCity or Municipal Highway Agency
Maintained byCity or Municipal Highway Agency
Historic statusNot eligible for the National Register of Historic Places
Work proposedOther structural work, including hydraulic replacements
Estimated improvement cost$48,000
NavigationNo navigation control on waterway

Frequently asked questions

When was Mannasota Avenue over Herring Run built?

It was built in 1928, making it 97 years old in 2025.

What condition is Mannasota Avenue over Herring 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 October 2024.

How much traffic does Mannasota Avenue over Herring Run carry?

About 2,933 vehicles per day (2020 count), of which roughly 5% are trucks.

How long is Mannasota Avenue over Herring Run?

The structure is 56 ft (17.1 m) long with a longest span of 52 ft (15.9 m) and a deck 49 ft wide.

Who owns Mannasota Avenue over Herring Run?

It is owned by the City or Municipal Highway Agency.