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Bridge conditions in Decatur County, Iowa

199 inventoried bridges · 78 rated poor · 2025 National Bridge Inventory

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

Of the 199 Decatur County bridges in the federal inventory, 78 carry a poor rating. That 39.2% share is roughly 6x the national average.

78 of the 199 bridges in Decatur County, Iowa, are rated in poor condition (39.2%) in the 2025 National Bridge Inventory, as of August 20, 2026.
37 bridges (18.6%) are rated good and 84 (42.2%) fair.
The median Decatur County bridge was built in 1970.
The busiest poor-rated bridge is US 69 over Zadie Creek (built 1925), carrying about 610 vehicles a day.

Good 18.6% · Fair 42.2% · Poor 39.2% of 199 bridges

Bridges rated poor

Every bridge in the county with a poor rating, busiest first. Poor means a major component is rated 4 or lower on FHWA's 0-9 scale; it is a repair flag, not a closure notice.

Bridge	Built	Vehicles/day	Condition
US 69 over Zadie Creek	1925	610	Poor
FM over Weldon River	1957	421	Poor
FM over Weldon River	1958	379	Poor
FM over Grand River	1959	329	Poor
FM over North Elk Creek	1939	278	Poor
FM over Small Natural Stream	1939	278	Poor
FM over Elk Creek	1958	240	Poor
FM over Seven Mile Creek	1969	190	Poor
Local over Stream	1960	190	Poor
FM over Little River	1959	170	Poor
FM over Seven Mile Creek	1957	131	Poor
Local over East Fork Big Creek	1967	113	Poor
FM over Little River	1957	110	Poor
Local over Seven Mile Creek	1963	103	Poor
Local over Seven Mile Creek	1980	82	Poor
FM over Weldon River	1951	79	Poor
FM over Stream	1962	79	Poor
Local over Zadie Creek	1964	72	Poor
Local over Little River	1943	72	Poor
Local over Dickenson Branch	1949	62	Poor
FM over Stream	1940	60	Poor
FM over Pot Hole Creek	1957	60	Poor
FM over Stream	1957	60	Poor
FM over Brush Creek	1980	60	Poor
FM over Trib of Little River	1969	60	Poor
FM over Shane Creek	1950	50	Poor
Local over Trib of Dickenson Branch	1965	46	Poor
Local over Kilgore Creek	1979	46	Poor
FM over Grand River	1962	45	Poor
Local over Stream	1961	41	Poor
FM over Steele Creek	1952	40	Poor
FM over Elk Creek	1900	40	Poor
FM over Jonathon Creek	1961	40	Poor
Local over Weldon River	1955	35	Poor
Local Rd over Wolf Creek	1978	35	Poor
115TH St over Wolf Creek	1957	34	Poor
Local over Little River	1980	30	Poor
Local over Weldon River	1962	30	Poor
Local over Short Creek	1967	30	Poor
FM over Jonathan Creek	1920	29	Poor
FM over Stream	1952	29	Poor
FM over Bee Creek	1957	29	Poor
Local over Lick Branch of Weldon R	1958	26	Poor
FM over Elk Creek	1983	26	Poor
Local over Weldon Creek	1916	26	Poor
FM over Weldon River	1973	26	Poor
FM over Long Creek	1957	26	Poor
Local over Stream	1988	21	Poor
207TH Ave over Stream	1977	21	Poor
Local over Kilgore Creek	1982	21	Poor
Local over Stream	1961	21	Poor
Local over Brush Creek	1920	21	Poor
Local over Little River	1960	21	Poor
Local over Long Creek	1930	21	Poor
FM over West Elk Creek	1961	20	Poor
Local over Elk Creek	1921	15	Poor
Local over W Fork Big Creek	1929	15	Poor
Local over W. Fork Big Creek	1970	15	Poor
FM over Weldon River	1957	15	Poor
Local over Elk Creek	1961	15	Poor
Local over Long Creek	1915	15	Poor
FM over Short Creek	1929	15	Poor
Local over Steel Creek	1927	11	Poor
Local over Drainage	1976	11	Poor
Local over Weldon River	1966	11	Poor
Local over Creek	1958	11	Poor
Local over Wolf Creek	1964	11	Poor
FM over Long Creek	1968	11	Poor
Local over Stream	1967	11	Poor
117TH St over Sand Creek	1900	11	Poor
Local over Stream	1966	10	Poor
Field Entrance over Side Ditch	1963	10	Poor
Local over Trib of Dickenson Branch	1967	5	Poor
Local over Trib of Weldon River	1910	5	Poor
Local over Shane Creek	1967	5	Poor
Local over Weldon River	1991	5	Poor
Local over West Little River	1930	5	Poor
250TH Ave over Stream	1972	5	Poor

Busiest bridges in the county

Bridge	Built	Vehicles/day	Condition
Rest Area Road over Rest Area Road	1994	13,800	Fair
SB I-35 over Grand River	1970	7,700	Fair
NB I-35 over Grand River	1970	7,550	Fair
SB I-35 over 310TH Street	1970	7,250	Fair
SB I-35 over Stream	1970	7,250	Good
NB I-35 over 310TH St	1970	7,100	Fair
NB I-35 over Stream	1970	7,100	Fair
NB I-35 over Stream	1970	7,100	Fair
SB I-35 over 324TH Street	1970	7,000	Fair
NB I-35 over 324TH Street	1970	6,900	Fair

Source: FHWA National Bridge Inventory, 2025. Counts cover inventoried highway bridges over 20 feet; ratings are reported by the state DOT.

All of Iowa: Iowa bridge conditions by county · every download on the data page.

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