US Bridges

SH 31 Log 6.21 over Slough 78

Fair

Lonoke County, Arkansas · 1 MI N of JCT US 165 · Structure no. 000000000002757

Built
1954
71 years old
Condition
Fair
inspected March 2025
Type
Slab
Concrete
Length
72 ft
4 main spans
Daily traffic
770
2018 count
Owner
State
State Highway Agency

About this bridge

SH 31 Log 6.21 over Slough 78 is a concrete slab carrying SH 31 Log 6.21 over Slough 78 in Lonoke County, Arkansas. It was built in 1954, so it is 71 years old, older than the Arkansas average of 45.1 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 770 vehicles a day, roughly 9% of them trucks, projected to reach 967 by 2028. The structure is 72 ft (21.9 m) long and 27 ft wide. If it were closed, the detour would be 14.3 mi (23 km).

Location

Open in Google Maps
CarriesSH 31 Log 6.21
CrossesSlough 78
Location1 MI N of JCT US 165
RouteState Highway 31
CountyLonoke County
StateArkansas
Coordinates34.56069, -91.88711
Functional classRural Minor Arterial

Condition and inspection

Fair

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

ComponentRatingMeaning
Deck5 FairAll primary structural elements are sound but may have minor section loss, cracking, spalling or scour.
Superstructure5 FairAll primary structural elements are sound but may have minor section loss, cracking, spalling or scour.
Substructure5 FairAll primary structural elements are sound but may have minor section loss, cracking, spalling or scour.
Channel and channel protection6 SatisfactoryStructural elements show some minor deterioration.
Last inspectionMarch 2025
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 geometry4: Meets minimum tolerable limits to be left in place as is
Waterway adequacy8: Equal to present desirable criteria
Approach roadway alignment8: Equal to present desirable criteria
Operating rating38 US tons
Inventory rating23 US tons

Structure

Structure typeSlab
MaterialConcrete
DeckConcrete, cast-in-place
Main spans4
Design loadH 15
Structure length72 ft (21.9 m)
Longest span18 ft (5.5 m)
Deck width27 ft (8.1 m)
Roadway width24 ft (7.3 m)
Vertical clearance over deckUnrestricted

Traffic and service

Average daily traffic770 (2018)
Projected traffic967 by 2028
Trucks9%
Lanes on structure2
Traffic directionTwo-way traffic
CarriesHighway
CrossesWaterway
Detour if closed14.3 mi (23 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 SH 31 Log 6.21 over Slough 78 built?

It was built in 1954, making it 71 years old in 2025.

What condition is SH 31 Log 6.21 over Slough 78 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 March 2025.

How much traffic does SH 31 Log 6.21 over Slough 78 carry?

About 770 vehicles per day (2018 count), of which roughly 9% are trucks.

How long is SH 31 Log 6.21 over Slough 78?

The structure is 72 ft (21.9 m) long with a longest span of 18 ft (5.5 m) and a deck 27 ft wide.

Who owns SH 31 Log 6.21 over Slough 78?

It is owned by the State Highway Agency.