US Bridges

School Road over Speaker-Maple Valley Drn

Fair

Sanilac County, Michigan · Sec 8 Speaker Twp · Structure no. 000000000009646

Built
1970
55 years old
Condition
Fair
inspected May 2024
Type
Culvert
Steel
Length
20 ft
1 main span
Daily traffic
225
2010 count
Owner
County
County Highway Agency

About this bridge

School Road over Speaker-Maple Valley Drn is a steel culvert carrying School Road over Speaker-Maple Valley Drn in Sanilac County, Michigan. It was built in 1970, so it is 55 years old, older than the Michigan average of 48.3 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 225 vehicles a day, roughly 2% of them trucks, projected to reach 405 by 2030. The structure is 20 ft (6.1 m) long. If it were closed, the detour would be 6.8 mi (11 km).

Location

Open in Google Maps
CarriesSchool Road
CrossesSpeaker-Maple Valley Drn
LocationSec 8 Speaker Twp
RouteCounty Highway 0
CountySanilac County
StateMichigan
Coordinates43.22811, -82.85447
Functional classRural Local

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 protection5 FairAll primary structural elements are sound but may have minor section loss, cracking, spalling or scour.
Culvert5 FairAll primary structural elements are sound but may have minor section loss, cracking, spalling or scour.
Last inspectionMay 2024
Inspection intervalevery 24 months
Operating statusOpen, no restriction
ScourUnknown foundation; not evaluated for scour
Structural evaluation5: Somewhat better than minimum adequacy to tolerate being left in place as is
Waterway adequacy6: Equal to present minimum criteria
Approach roadway alignment6: Equal to present minimum criteria
Operating rating45.3 US tons
Inventory rating27.1 US tons

Structure

Structure typeCulvert
MaterialSteel
DeckNot applicable
Main spans1
Design loadH 20
Structure length20 ft (6.1 m)
Longest span20 ft (6.1 m)
Deck width0 ft (0 m)
Roadway width0 ft (0 m)
Vertical clearance over deckUnrestricted

Traffic and service

Average daily traffic225 (2010)
Projected traffic405 by 2030
Trucks2%
Lanes on structure2
Traffic directionTwo-way traffic
CarriesHighway
CrossesWaterway
Detour if closed6.8 mi (11 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 proposedNone recorded
Estimated improvement cost—
NavigationNo navigation control on waterway

Frequently asked questions

When was School Road over Speaker-Maple Valley Drn built?

It was built in 1970, making it 55 years old in 2025.

What condition is School Road over Speaker-Maple Valley Drn 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 May 2024.

How much traffic does School Road over Speaker-Maple Valley Drn carry?

About 225 vehicles per day (2010 count), of which roughly 2% are trucks.

How long is School Road over Speaker-Maple Valley Drn?

The structure is 20 ft (6.1 m) long with a longest span of 20 ft (6.1 m).

Who owns School Road over Speaker-Maple Valley Drn?

It is owned by the County Highway Agency.