Home › Idaho › Custer County › All bridges

Every bridge in Custer County, Idaho

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

126 inventoried bridges, busiest first

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

Custer County, Idaho, has 126 bridges in the 2025 National Bridge Inventory: 40 rated good, 72 fair, and 14 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
US 93 over Garden Creek	1941	2,300	Fair
SH 21 over Crooked Creek	1968	2,200	Fair
US 93 over Big Lost River	1987	1,500	Fair
US 93 over Challis Creek	1991	1,400	Good
US 93 over Salmon River;challis Br.	1995	1,400	Good
Capitol Avenue over Swauger Slough	1940	1,220	Fair
SH 75 over Gini Canal	1988	1,100	Good
SH 75 over Redfish Lake Creek	1960	1,100	Fair
SH 75 over Salmon River	1954	1,100	Fair
US 93 over Pahsimeroi River	1938	1,100	Fair
US 93 over Salmon River (watts Br.)	2009	1,100	Good
US 93 over Warm Spring Creek	2018	810	Good
SH 75 over Champion Creek	1974	800	Fair
SH 75 over Fourth of July Creek	1974	800	Fair
SH 75 over Salmon River	1985	800	Fair
SH 75 over Salmon River	1985	800	Fair
SH 75 over Basin Creek	2007	680	Fair
SH 75 over Salmon River; W. Clayton	2008	680	Good
SH 75 over Salmon River;slate CR Br	2011	680	Good
SH 75 over Valley Creek	1977	680	Fair
SH 75 over Yankee Fk of Salmon Rivr	1934	680	Poor
SH 21 over Cape Horn Creek	1964	620	Fair
SH 21 over Elk Creek	2022	620	Fair
SH 21 over Stanley Lake Creek	1966	620	Fair
SH 75 over Bradshaw Creek	1988	600	Good
SH 75 over E. Fk. Salmon River	2014	600	Good
SH 75 over Malm Gulch	1988	600	Good
SH 75 over Salmon River;e. Clayton	2014	600	Good
Fdr over Redfish Lake Creek	2015	500	Good
Challis Creek Rd over Challis Creek	1997	480	Good
STC6868;TRAIL Crk over N. Fork Big Lost River	1970	440	Fair
STC6868;TRAIL Crk over N. Fork Big Lost River	1970	440	Fair
Squaw Creek Rd over Squaw Creek	1960	330	Poor
Squaw Creek Road over Squaw Creek	1960	330	Poor
STC6868;TRAIL Crk over N. Fork Big Lost River	2016	300	Good
Squaw Creek Rd over Squaw Creek	1960	300	Poor
STC6702;SMELTER Rd over Big Lost River	1974	260	Fair
Yankee Fork Road over Yankee Fork Creek	1966	200	Fair
Bayhorse Road over Salmon River;bayhorse CR	1930	170	Fair
Houston Road over Big Lost River	1973	170	Fair
S6869;FSH Hatchry over Big Lost River(pence Br)	2018	160	Good
STC6867;GARDEN Crk over Garden Creek	2020	140	Good
Bartlett Road over Big Lost River	1996	110	Fair
Squaw Creek Rd over Salmon River;sw.clayton	1970	106	Fair
Beaver-loon Road over Jordan Creek	2001	100	Fair
Beaver-loon Road over Jordan Creek	1993	100	Poor
Beaver-loon Road over Jordan Creek	1957	100	Poor
Custer Motorway over Yankee Fork	1992	100	Poor
Custer Motorway over Yankee Fork	1962	100	Fair
Custer Motorway over Yankee Fork	1969	100	Fair
Custer Motorway over Yankee Fork	1973	100	Fair
Custer Motorway over Yankee Fork	2004	100	Fair
Custer Motorway over Yankee Fork River	1961	100	Fair
Custer Road over Sulphur Creek	2012	100	Good
Dowton Lane over Pahsimeroi River	2016	100	Good
Fdr over Fourth of July Creek	1992	100	Good
Houston Rd over Big Lost River	1992	100	Good
No Data Entered over Jordan Creek	1972	100	Fair
No Data Entered over No Data Entered	1972	100	Good
Squaw Creek Rd over Squaw Creek	1960	100	Poor
East Fork Rd over E.fk.salmon River	1970	90	Fair
East Fork Rd over E.fk.salmon River	1972	90	Fair
East Fork Rd over Road Creek	2022	90	Poor
Morgan Crk Rd over Morgan Creek;ne.challis	1977	90	Good
Fdr over Big Casino Creek	1969	80	Good
Old Chilli Road over Thousand Springs Creek	1926	80	Poor
Hooper Lane over Pahsimeroi River	2011	70	Good
Fdr over Valley Creek	1986	60	Good
Mule Shoe Mine Rd over Salmon River;se.clayton	1930	60	Poor
3700 North over Big Lost River	2010	50	Good
4100 W over Big Lost River	1977	50	Fair
Beaver Creek Road over Beaver Creek	1953	50	Fair
Beaver Creek Road over Marsh Creek	1964	50	Fair
Fdr over Alturas Lake Creek	1955	50	Fair
Fdr over Big Boulder Creek	1980	50	Good
Fdr over East Fork Salmon River	1989	50	Good
Fdr over East Fork Salmon River	1989	50	Fair
Fdr over East Fork Salmon River	1960	50	Fair
Fdr over East Fork Salmon River	1991	50	Fair
Fdr over Fishhook Creek	1975	50	Good
Fdr over Fishhook Creek	1956	50	Fair
Fdr over Germania Ceeek	1956	50	Fair
Fdr over Hell Roaring Creek	1984	50	Fair
Fdr over Huckelberry Creek	1984	50	Good
Fdr over Iron Creek	2012	50	Good
Fdr over Pettit Lake Creek	1982	50	Poor
Fdr over Salmon River	1960	50	Fair
Fdr over Salmon River	1967	50	Fair
Fdr over Salmon River	1969	50	Fair
Fdr over Slate Creek	1976	50	Good
Fdr over Stanley Lake Creek	1969	50	Fair
Fdr over Valley Creek	1950	50	Poor
No Data Entered over No Data Entered	1972	50	Poor
No Data Entered over Yankee Fork	1972	50	Fair
No Data Entered over Yankee Fork	1972	50	Fair
No Data Entered over Yankee Fork	1972	50	Fair
Basin Creek Road over East Fork Basin Creek	1979	40	Fair
Corral Canyon Road over N. Fk. Big Lost River	1979	40	Fair
Old Chilly Rd over Big Lost River	2023	40	Good
Sawmill Canyon Rd over Little Lost River	1957	40	Fair
Thompson CR Road over Thompson Creek	1982	40	Fair
Trealor Creek Road over Sq___ Creek	1966	40	Fair
3800 North Rd over Big Lost River	2007	30	Good
STC6870;PAHSIMEROI over Big Creek Fish Passage	2014	30	Good
1901: Herd Creek over East Fork Salmon River	1964	25	Good
1920: Darling Cree over Challis Creek	1981	25	Good
1920: Darling Cree over West Fork Morgan Creek	1995	25	Good
1979: Old Stage over Morgan Creek	2004	25	Good
E Fork Road over Star Hope Creek	1980	25	Fair
E Fork Road over Wildhorse Creek	1970	25	Fair
Wildhorse Creek Rd over Wildhorse Creek	1970	25	Fair
Copper Basin Loop over Star Hope Creek	1970	20	Fair
Sq___ Creek Road over Paasasikwana Naokwaide	1964	20	Fair
Sq___ Creek Road over Paasasikwana Naokwaide	1964	20	Fair
Beaver Creek Road over Float Creek	1967	10	Fair
Beaver Creek Road over Seafoam Creek	1968	10	Fair
Beaver-loon Road over Beaver Creek	1967	10	Fair
Beaver-loon Road over Loon Creek	1957	10	Fair
Beaver-loon Road over Nelson Creek	1967	10	Fair
Beaver-loon Road over W. Fk. Mayfield Creek	1967	10	Fair
Beaver-loon Road over W.fk Mayfield Creek	1968	10	Fair
Beaver-loon Road over W.fk. Mayfield Creek	1968	10	Fair
Bull Creek Road over Little Lost River	1971	10	Fair
Redrock Loop over Little Lost River	1966	10	Good
Road over Knapp Creek	1964	10	Fair
Beaver-loon Road over Beaver Creek	1972	5	Fair

Source: FHWA National Bridge Inventory, 2025.

Custer County bridge conditions · Idaho bridges by county.

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