US Bridges

County Highway #7 over Cottonwood Ck

Poor

Mellette County, South Dakota · 5W & 4.2N White Rv · Structure no. 000000048200168

Built
1982
43 years old
Condition
Poor
inspected July 2024
Type
Tee Beam
Prestressed Concrete
Length
51 ft
1 main span
Daily traffic
9
2022 count
Owner
County
County Highway Agency

About this bridge

County Highway #7 over Cottonwood Ck is a prestressed concrete tee beam carrying County Highway #7 over Cottonwood Ck in Mellette County, South Dakota. It was built in 1982, so it is 43 years old, younger than the South Dakota average of 48.9 years.

The most recent inspection reported to the Federal Highway Administration rates it in poor condition with a lowest component rating of 4 out of 9. The lowest-rated primary component is rated 4 or below, indicating advanced deterioration. Poor does not mean unsafe; such bridges are inspected more often and may carry load restrictions.

It carries about 9 vehicles a day, roughly 2% of them trucks, projected to reach 20 by 2032. The structure is 51 ft (15.5 m) long and 31 ft wide. If it were closed, the detour would be 16.8 mi (27 km).

Location

Open in Google Maps
CarriesCounty Highway #7
CrossesCottonwood Ck
Location5W & 4.2N White Rv
RouteCounty Highway 0
CountyMellette County
StateSouth Dakota
Coordinates43.62495, -100.85006
Functional classRural Local

Condition and inspection

Poor

The lowest-rated primary component is rated 4 or below, indicating advanced deterioration. Poor does not mean unsafe; such bridges are inspected more often and may carry load restrictions.

ComponentRatingMeaning
Deck6 SatisfactoryStructural elements show some minor deterioration.
Superstructure7 GoodSome minor problems.
Substructure4 PoorAdvanced section loss, deterioration, spalling or scour.
Channel and channel protection6 SatisfactoryStructural elements show some minor deterioration.
Last inspectionJuly 2024
Inspection intervalevery 24 months
Operating statusOpen, no restriction
ScourFoundations stable; scour above top of footing
Structural evaluation4: Meets minimum tolerable limits to be left in place as is
Deck geometry7: Better than present minimum criteria
Waterway adequacy7: Better than present minimum criteria
Approach roadway alignment7: Better than present minimum criteria
Operating rating36 US tons
Inventory rating21.1 US tons

Structure

Structure typeTee Beam
MaterialPrestressed Concrete
DeckConcrete, precast panels
Main spans1
Design loadHS 20
Structure length51 ft (15.5 m)
Longest span49 ft (14.9 m)
Deck width31 ft (9.4 m)
Roadway width30 ft (9.1 m)
Vertical clearance over deckUnrestricted

Traffic and service

Average daily traffic9 (2022)
Projected traffic20 by 2032
Trucks2%
Lanes on structure2
Traffic directionTwo-way traffic
CarriesHighway
CrossesWaterway
Detour if closed16.8 mi (27 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$66,000
NavigationNo navigation control on waterway

Frequently asked questions

When was County Highway #7 over Cottonwood Ck built?

It was built in 1982, making it 43 years old in 2025.

What condition is County Highway #7 over Cottonwood Ck in?

The National Bridge Inventory rates it in poor condition. The lowest-rated primary component is rated 4 or below, indicating advanced deterioration. Poor does not mean unsafe; such bridges are inspected more often and may carry load restrictions. The last reported inspection was in July 2024.

How much traffic does County Highway #7 over Cottonwood Ck carry?

About 9 vehicles per day (2022 count), of which roughly 2% are trucks.

How long is County Highway #7 over Cottonwood Ck?

The structure is 51 ft (15.5 m) long with a longest span of 49 ft (14.9 m) and a deck 31 ft wide.

Who owns County Highway #7 over Cottonwood Ck?

It is owned by the County Highway Agency.