US Bridges

300th RD over Br N Blackbird CR

Good

Putnam County, Missouri · S 11 T 66 N R 19 W · Structure no. 16643

Built
1994
31 years old
Condition
Good
inspected February 2023
Type
Stringer/Multi-beam or Girder
Steel
Length
60 ft
1 main span
Daily traffic
20
2024 count
Owner
County
County Highway Agency

About this bridge

300th RD over Br N Blackbird CR is a steel stringer/multi-beam or girder carrying 300th RD over Br N Blackbird CR in Putnam County, Missouri. It was built in 1994, so it is 31 years old, younger than the Missouri average of 45.1 years.

The most recent inspection reported to the Federal Highway Administration rates it in good condition with a lowest component rating of 8 out of 9. All primary components (deck, superstructure, substructure, or culvert) are rated 7 or higher. No significant problems were noted.

It carries about 20 vehicles a day, roughly 10% of them trucks, projected to reach 22 by 2044. The structure is 60 ft (18.3 m) long and 18 ft wide. If it were closed, the detour would be 5 mi (8 km).

Location

Open in Google Maps
Carries300th RD
CrossesBr N Blackbird CR
LocationS 11 T 66 N R 19 W
RouteCounty Highway 127
CountyPutnam County
StateMissouri
Coordinates40.53022, -92.99517
Functional classRural Local

Condition and inspection

Good

All primary components (deck, superstructure, substructure, or culvert) are rated 7 or higher. No significant problems were noted.

ComponentRatingMeaning
Deck8 Very GoodNo problems noted.
Superstructure8 Very GoodNo problems noted.
Substructure8 Very GoodNo problems noted.
Channel and channel protection6 SatisfactoryStructural elements show some minor deterioration.
Last inspectionFebruary 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 geometry3: Basically intolerable, requiring high priority of corrective action
Waterway adequacy7: Better than present minimum criteria
Approach roadway alignment8: Equal to present desirable criteria
Operating rating30.8 US tons
Inventory rating17.9 US tons

Structure

Structure typeStringer/Multi-beam or Girder
MaterialSteel
DeckConcrete, cast-in-place
Main spans1
Design loadOther
Structure length60 ft (18.3 m)
Longest span59 ft (18 m)
Deck width18 ft (5.5 m)
Roadway width18 ft (5.4 m)
Vertical clearance over deckUnrestricted

Traffic and service

Average daily traffic20 (2024)
Projected traffic22 by 2044
Trucks10%
Lanes on structure2
Traffic directionTwo-way traffic
CarriesHighway
CrossesWaterway
Detour if closed5 mi (8 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 proposedRehabilitation because of general structure deterioration or inadequate strength
Estimated improvement cost$309,000 (2025 estimate)
NavigationNo navigation control on waterway

Frequently asked questions

When was 300th RD over Br N Blackbird CR built?

It was built in 1994, making it 31 years old in 2025.

What condition is 300th RD over Br N Blackbird CR in?

The National Bridge Inventory rates it in good condition. All primary components (deck, superstructure, substructure, or culvert) are rated 7 or higher. No significant problems were noted. The last reported inspection was in February 2023.

How much traffic does 300th RD over Br N Blackbird CR carry?

About 20 vehicles per day (2024 count), of which roughly 10% are trucks.

How long is 300th RD over Br N Blackbird CR?

The structure is 60 ft (18.3 m) long with a longest span of 59 ft (18 m) and a deck 18 ft wide.

Who owns 300th RD over Br N Blackbird CR?

It is owned by the County Highway Agency.