161 St over I029

Codington County, South Dakota · rated Fair in the 2025 National Bridge Inventory

United States Bridge Conditions2025 National Bridge Inventory, FHWACompiled August 20, 2026

161 St over I029 in Codington County, South Dakota, is rated in fair condition in the 2025 National Bridge Inventory (as of August 20, 2026).
Its lowest-rated component is the deck, rated 6 (satisfactory condition) on the 0-9 scale.
It was built in 1974, making it 51 years old at the 2025 inventory.
It carries about 77 vehicles a day (traffic count year 2023).
Its listed owner is the state highway agency.
It is one of 46 of the 75 inventoried bridges in Codington County rated fair (61.3%); 14 (18.7%) are rated poor.
A fair rating means the lowest-rated major component scores 5 or 6 on FHWA's 0-9 scale: some deterioration or minor section loss, but the structure is sound. It is the middle class, not a warning.

Component ratings


Structure	Continuous steel stringer or multi-beam girder
Length	about 296 ft
Location	4 S Sd 20 Interch
NBI structure number	000000015215070
Condition class	Fair

Source: FHWA National Bridge Inventory, 2025 data as reported by the South Dakota department of transportation.

Bridge	Built	Vehicles/day	Condition
US212 over Big Sioux Rv	2019	14,592	Good
US212 Ser Rd over Ck	1970	12,968	Fair
US212 over Willow Ck	1970	10,862	Fair
US081 over Big Sioux Rv	1966	7,665	Fair
W Kemp Avenue over Big Sioux River	1935	5,053	Fair
14TH Ave. N Wtn. over Big Sioux Rv	1974	4,970	Poor