Oldest Dams in Iowa

Iowa has 4098 dams with recorded construction dates. The oldest dates to 1857 — 169 years ago. Iowa's earliest dams were built in the 19th century, an era of westward expansion, irrigation development, and early water infrastructure. Older dams require particular attention for safety, as many were built before modern engineering standards.

#	Dam	County	Year Built	Age	Height (ft)	Hazard	Condition
1	Vernon Spring Dam	Howard	1857	169 yrs	8	Low	Not assessed
2	Lidtke Mill Dam	Howard	1860	166 yrs	12	Low	Not assessed
3	Waverly Milldam	Bremer	1872	154 yrs	12	Low	Satisfactory
4	Fairbank Dam	Buchanan	1880	146 yrs	12	Low	Not assessed
5	Coralville Milldam	Johnson	1880	146 yrs	13	Low	Not assessed
6	Fairfield Water Works Dam No 1	Jefferson	1888	138 yrs	40	Significant	Satisfactory
7	Nora Springs Low Head Dam	Floyd	1895	131 yrs	12	Low	Not assessed
8	Grade Lake Dam	Clarke	1900	126 yrs	44	High	Satisfactory
9	Q Pond Park Dam	Clarke	1900	126 yrs	34	Low	Not assessed
10	Crystal Lake Dam	Clinton	1900	126 yrs	24	Low	Not assessed
11	Fairfield Waterworks Dam No 2	Jefferson	1900	126 yrs	33	Low	Satisfactory
12	Walton Lake Dam	Jefferson	1900	126 yrs	35	Significant	Satisfactory
13	Strunk Dam	Lee	1900	126 yrs	41	Low	Not assessed
14	Lineville Reservoir Dam	Wayne	1900	126 yrs	21	Low	Not assessed
15	Promise City Reservoir Dam	Wayne	1900	126 yrs	25	Low	Not assessed
16	Bobwhite Lake Dam	Wayne	1900	126 yrs	27	Significant	Fair
17	Otranto Dam	Mitchell	1902	124 yrs	7	Low	Not assessed
18	Manchester Milldam	Delaware	1905	121 yrs	11	Low	Not assessed
19	Burlington Street Dam	Johnson	1906	120 yrs	20	Low	Not assessed
20	Lake Oelwein Dam	Fayette	1908	118 yrs	16	Low	Not assessed
21	Seymour Reservoir Dam	Wayne	1908	118 yrs	24	Low	Fair
22	Anamosa	Jones	1909	117 yrs	12	Low	Satisfactory
23	Oakland Mills Dam	Henry	1910	116 yrs	10	Low	Satisfactory
24	New London Country Club Dam	Henry	1910	116 yrs	26	Low	Satisfactory
25	Fraser Milldam	Boone	1911	115 yrs	7	Low	Not assessed
26	Decorah Upper Milldam	Winneshiek	1911	115 yrs	8	Low	Not assessed
27	Upper Centerville Reservoir Dam	Appanoose	1912	114 yrs	48	Significant	Fair
28	Lower Centerville Reservoir Dam	Appanoose	1912	114 yrs	39	Significant	Fair
29	Humboldt Milldam	Humboldt	1912	114 yrs	13	Low	Not assessed
30	East Lenox Reservoir Dam	Adams	1913	113 yrs	25	Significant	Satisfactory
31	Redfield Dam	Dallas	1913	113 yrs	9	Low	Not assessed
32	Marble Rock Milldam	Floyd	1913	113 yrs	15	Low	Not assessed
33	West Lenox Reservoir Dam	Taylor	1913	113 yrs	25	Significant	Not assessed
34	Waucoma Milldam	Fayette	1914	112 yrs	11	Low	Not assessed
35	Monticello Milldam	Jones	1914	112 yrs	12	Low	Not assessed
36	Fort Atkinson Milldam	Winneshiek	1914	112 yrs	11	Low	Not assessed
37	Waterloo Milldam	Black Hawk	1915	111 yrs	7	Low	Satisfactory
38	East Lake Dam	Clarke	1915	111 yrs	41	Significant	Satisfactory
39	Williamson Pond Dam	Lucas	1915	111 yrs	32	Low	Not assessed
40	Crystal Lake Dam	Lucas	1915	111 yrs	27	Significant	Fair
41	Des Moines-center Street Milldam	Polk	1916	110 yrs	11	Low	Not assessed
42	Black Hawk Lake Dam	Sac	1916	110 yrs	12	Significant	Satisfactory
43	Humeston Reservoir Dam	Wayne	1916	110 yrs	31	Significant	Poor
44	Corning Reservoir Dam	Adams	1917	109 yrs	30	Significant	Satisfactory
45	Nashua Milldam	Chickasaw	1917	109 yrs	20	Significant	Fair
46	Lynnville Dam	Jasper	1918	108 yrs	12	Low	Not assessed
47	St Ansgar Milldam	Mitchell	1919	107 yrs	9	Low	Not assessed
48	Homepond Dam	Decatur	1920	106 yrs	30	Significant	Fair
49	Des Moines-scott Street Milldam	Polk	1920	106 yrs	7	Low	Not assessed
50	Old Reservoir Dam	Ringgold	1920	106 yrs	25	Low	Not assessed

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