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Every bridge in Union County, South Dakota

Name: Every bridge in Union County, South Dakota
Creator: Bridge Report Card
License: https://creativecommons.org/publicdomain/zero/1.0/

169 inventoried bridges, busiest first

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

Union County, South Dakota, has 169 bridges in the 2025 National Bridge Inventory: 51 rated good, 77 fair, and 41 poor (as of August 20, 2026).
This index lists every one of them, busiest first; each links to its own condition record.

Bridge	Built	Vehicles/day	Condition
I029 N over Big Sioux Rv	1963	18,090	Fair
I029 S over Big Sioux Rv	1990	18,090	Good
I029 over Ck	1961	11,970	Good
I029 over Ck	1961	11,970	Good
I029 over Ck	1961	11,970	Good
I029 N over River Drive	1981	9,870	Good
I029 S over River Drive	1981	9,870	Good
I029 N over 302 St (fas 6372)	1960	8,020	Poor
I029 S over 302 St (fas 6372)	1960	8,020	Fair
I029 N over Ck	1961	7,770	Fair
I029 S over Ck	1961	7,770	Fair
I029 N over Bn RR	1960	7,235	Fair
I029 N over SD029 L	1994	7,235	Good
I029 S over Bn RR	1960	7,235	Fair
I029 S over SD029 L	1993	7,235	Fair
Dakota Dunes Blvd over I029	1991	5,584	Fair
SD046 over I029	2000	4,726	Good
SD029 P over I029	1961	3,276	Fair
SD029 L over I029	1960	2,305	Fair
SD046 over Br East Brule Ck	2024	1,994	Good
SD046 over West Brule Ck	2024	1,994	Good
SD046 over Ck	1954	1,745	Fair
SD046 over East Brule Ck	1954	1,745	Fair
SD046 over Ck	1954	1,725	Fair
SD46 over Big Sioux River	1991	1,610	Fair
SD011 over Ck	1965	1,575	Good
SD050 over Big Sioux River	2010	1,570	Good
SD050 over Ck	2017	1,366	Good
SD050 over I029	1960	1,366	Fair
SD011 over East Brule Ck	1965	1,294	Fair
SD011 over East Brule Ck	1965	1,294	Good
SD050 over Brule Ck	1960	1,292	Fair
SD050 over Drainage Ditch	1960	1,292	Fair
SD048 over Drainage Ditch	1960	1,173	Fair
SD048 over East Union Ck	1960	1,173	Fair
SD048 over West Union Ck	1960	1,173	Fair
SD048 over I029	1961	847	Fair
SD011 over Drainage Ditch	1983	776	Fair
SD048 over Brule Ck	1957	758	Fair
SD048 over Ck	1957	758	Fair
SD048 over Ck	1956	758	Fair
47860 307TH St over West Union Ck	1950	500	Good
48480 Co Hwy 13 over Green Ck	1985	500	Poor
48580 County Rd 13 over Big Sioux Rv	1979	500	Fair
330TH Street over I029	1961	488	Fair
47160 302 St over Ck	1960	450	Fair
47400 302 St. over West Brule Ck	1960	435	Poor
SD011 over West Union Ck	1969	406	Fair
30820 471 Ave. over Brule Ck	2016	400	Good
30890 471 Ave. over Brule Ck	2017	400	Good
31450 471 Ave. over Ck	1955	400	Good
30330 River Road over Ck	1972	325	Poor
30599 River Road over Ck	1989	325	Good
30999 477TH Ave over Ck	1989	300	Poor
31490 477TH Ave over Br Brule Ck	1955	300	Poor
31800 477TH Ave over Ck	1948	300	Good
31870 477TH Ave over County Ditch	1948	300	Good
30300 475TH Ave over East Brule Ck	2017	280	Good
306 St (fas 6370) over I029	1960	270	Fair
47580 302ND St over East Brule Ck	1960	270	Poor
472 Ave over I029	1960	250	Fair
484 Ave over I029	1961	240	Fair
47190 307 St. over East Brule Ck	2013	235	Good
482 Ave over I029	1961	195	Fair
48510 299TH Str. over Finnie Ck	2020	185	Good
47730 309 Str. over Ck	1977	180	Fair
30520 475TH Ave over Ck	2009	150	Good
480 Ave (fas 6285) over I029	1961	150	Fair
31390 481ST Ave over Drainage Ditch	1976	140	Fair
30620 475TH Ave over Ck	2022	125	Good
47910 299 St over Ck	2004	125	Fair
47700 301 St over Ck	2004	120	Fair
300 St over I029	2024	115	Good
47440 298TH St over West Brule Ck	2008	110	Good
48050 311TH St over East Union Ck	1950	110	Poor
31880 472 Ave over Big Ditch Ck	2006	105	Fair
47930 311TH St over West Union Ck	1981	100	Fair
48190 308 Str. over Ck	1940	100	Fair
SD048 Ef over Ck	1961	100	Fair
31150 475TH Ave over Ck	1939	97	Fair
31260 475TH Ave over Ck	2000	97	Fair
SD011 Sf over East Brule Ck	1984	96	Good
298 St over I029	1960	95	Fair
30490 473 Ave over Brule Ck	1940	75	Fair
29895 Boyer Ave over Ck	1992	70	Poor
478 Ave over I029	1961	65	Fair
31490 475TH St over Brule Ck	1977	60	Poor
48250 Virginia Rd over Ck	1991	55	Fair
48296 307TH St over Ck	1977	55	Fair
48480 298TH St over Ck	1987	55	Poor
30040 473 Ave. over Ck	2024	50	Good
30880 River Rd over Ck	1979	50	Fair
31180 476TH Ave over Ck	1993	50	Fair
32050 478TH Ave over Brule Ck	1983	50	Fair
47280 319TH Str. over Drainage Ditch	1940	50	Fair
47380 301ST St over West Brule Ck	2010	50	Good
47610 312TH St over Ck	1992	50	Poor
47670 301 St. over East Brule Ck	1944	50	Good
48340 301ST over Ck	2023	50	Good
SD011 Sf over West Union Ck	1969	50	Good
30010 478 Ave. over Ck	1982	45	Poor
30040 478 Ave. over Drainage Ditch	1983	45	Poor
30310 483RD Ave over Ck	1983	45	Poor
30320 482ND Ave over Ck	1983	45	Poor
31900 Lawrence Rd over Ck	1977	45	Good
32015 477TH Ave over Ck	1997	45	Good
32050 475TH Ave over Drainage Ditch	1993	45	Fair
47230 305 Str. over Ck	1987	45	Poor
47850 299TH St over East Brule Ck	1930	45	Fair
47880 306 Str. over Ck	1950	45	Poor
48020 309 Str. over East Union Ck	1950	45	Poor
48060 306 Str. over East Union Ck	1986	45	Fair
48140 312TH St over Ck	1940	45	Poor
48310 303RD St over Ck	1982	45	Fair
47320 304 Str over Ck	1970	43	Poor
30630 473 Ave. over Ck	1978	41	Good
30070 474TH Ave over West Brule Ck	1982	40	Poor
30590 474TH Ave over Ck	1983	40	Fair
30820 480 Ave. over Ck	1935	40	Poor
31080 473 Ave. over Ck	1950	40	Fair
31410 474TH Ave over Brule Ck	1986	40	Good
32200 477TH Ave over Lewis Ditch	1968	40	Poor
32201 478TH Ave. over Lewis Ditch	1940	40	Poor
47290 305 Str. over Brule Ck	1994	40	Good
47320 305 Str over Brule Ck	1989	40	Poor
47460 304 Str. over Brule Ck	1987	40	Poor
47920 310TH St over West Union Ck	2020	40	Good
47960 312TH St over West Union Ck	1986	40	Poor
48030 310 Str. over East Union Ck	1948	40	Poor
30430 474 Ave. over East Brule Ck	1986	36	Fair
30770 478 Ave. over Ck	1940	35	Fair
30940 476TH Ave over Ck	2016	35	Good
31070 476TH Ave over Ck	1963	35	Poor
31128 472ND Ave.rd over Brule Ck	1985	35	Poor
31160 474TH Ave over Ck	1945	35	Fair
31590 476 Th Ave over Brule Ck	2004	35	Fair
47160 310 Str. over Brule Ck	1970	35	Poor
47230 306 Str. over Brule Ck	1979	35	Poor
47250 300 Str. over Ck	1950	35	Fair
47340 306 Str. over Ck	1948	35	Poor
47700 300 Str. over Ck	1982	35	Poor
47870 308 Str. over West Union Ck	1957	35	Fair
48080 308 Str. over East Union Ck	1996	35	Fair
30250 484TH Ave over Ck	2021	34	Good
47610 316 St over Brule Ck	2006	32	Good
30330 472 Ave. over Ck	1973	30	Poor
30650 472 Ave. over Brule Ck	1989	30	Good
31270 473RD Ave over Brule Ck	1976	30	Fair
47260 311 St over Ck	1991	30	Fair
475 Ave over I029	1960	30	Fair
47560 312TH St over Ck	2007	30	Good
47570 311 Str. over Ck	1955	30	Poor
47605 310TH St over Ck	2020	30	Good
47690 310TH St over Ck	2020	30	Good
48150 313TH St. over Drainage Ditch	1950	30	Good
29730 484TH Ave over Ck	1983	25	Poor
30600 476 Ave. over Ck	1965	25	Poor
307 St over I029	1961	25	Fair
47110 309 Str. over Brule Ck	1989	25	Good
47180 311TH Street over Brule Ck	2002	25	Fair
47340 310TH St over Ck	1935	25	Poor
47380 312TH St over Ck	2007	25	Fair
48040 312TH St over East Union Ck	1950	25	Poor
309 St over I029	1961	20	Fair
47330 312TH St over Ck	1950	20	Good
47659 320 St. over Brule Ck	2005	15	Fair
47690 305 Str. over Ck	1989	15	Fair
31140 474TH Ave over Ck	1983	5	Good
SD048 over Big Sioux Rv	1996	–	Fair

Source: FHWA National Bridge Inventory, 2025.

Union County bridge conditions · South Dakota bridges by county.

Background: how bridge ratings work · what "poor" and "structurally deficient" actually mean · how often bridges are inspected.