US Bridges

Dobyns Rd. 631 over South Mayo River

Fair

Patrick County, Virginia · 0.52 Rt 787; 1.25 Rt 815 · Structure no. 000000000013289

Built
1983
42 years old
Condition
Fair
inspected August 2023
Type
Culvert
Concrete
Length
59 ft
4 main spans
Daily traffic
411
2022 count
Owner
State
State Highway Agency

About this bridge

Dobyns Rd. 631 over South Mayo River is a concrete culvert carrying Dobyns Rd. 631 over South Mayo River in Patrick County, Virginia. It was built in 1983, so it is 42 years old, younger than the Virginia average of 50.7 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 411 vehicles a day, roughly 1% of them trucks, projected to reach 458 by 2045. The structure is 59 ft (18 m) long. If it were closed, the detour would be 6.2 mi (10 km).

CarriesDobyns Rd. 631
CrossesSouth Mayo River
Location0.52 Rt 787; 1.25 Rt 815
RouteCounty Highway 631
Coordinates36.64139, -80.30049
Functional classRural Minor 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
Channel and channel protection7 GoodSome minor problems.
Culvert6 SatisfactoryStructural elements show some minor deterioration.
Last inspectionAugust 2023
Inspection intervalevery 24 months
Operating statusOpen, no restriction
ScourFoundations stable; scour above top of footing
Structural evaluation6: Equal to present minimum criteria
Waterway adequacy7: Better than present minimum criteria
Approach roadway alignment5: Somewhat better than minimum adequacy to tolerate being left in place as is
Operating rating60 US tons
Inventory rating36 US tons

Structure

Structure typeCulvert
MaterialConcrete
DeckNot applicable
Main spans4
Design loadHS 20
Structure length59 ft (18 m)
Longest span10 ft (3 m)
Deck width0 ft (0 m)
Roadway width0 ft (0 m)
Vertical clearance over deckUnrestricted

Traffic and service

Average daily traffic411 (2022)
Projected traffic458 by 2045
Trucks1%
Lanes on structure2
Traffic directionTwo-way traffic
CarriesHighway
CrossesWaterway
Detour if closed6.2 mi (10 km)
TollOn a free road
National Highway SystemNo

Ownership and planned work

OwnerState Highway Agency
Maintained byState 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 Dobyns Rd. 631 over South Mayo River built?

It was built in 1983, making it 42 years old in 2025.

What condition is Dobyns Rd. 631 over South Mayo 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 August 2023.

How much traffic does Dobyns Rd. 631 over South Mayo River carry?

About 411 vehicles per day (2022 count), of which roughly 1% are trucks.

How long is Dobyns Rd. 631 over South Mayo River?

The structure is 59 ft (18 m) long with a longest span of 10 ft (3 m).

Who owns Dobyns Rd. 631 over South Mayo River?

It is owned by the State Highway Agency.