Risky reservoirs: South Dakota counties where aging dams pose the greatest threat

- Total high-hazard dams: 5
- Number potentially dangerous: 1 (20.0%)
- Potentially dangerous dams include:
--- 1 in poor condition

- Total high-hazard dams: 3
- Number potentially dangerous: 1 (33.3%)
- Potentially dangerous dams include:
--- 1 in poor condition

- Total high-hazard dams: 6
- Number potentially dangerous: 2 (33.3%)
- Potentially dangerous dams include:
--- 2 not rated

- Total high-hazard dams: 2
- Number potentially dangerous: 1 (50.0%)
- Potentially dangerous dams include:
--- 1 condition withheld

- Total high-hazard dams: 2
- Number potentially dangerous: 1 (50.0%)
- Potentially dangerous dams include:
--- 1 in poor condition

- Total high-hazard dams: 14
- Number potentially dangerous: 10 (71.4%)
- Potentially dangerous dams include:
--- 1 in poor condition
--- 5 not rated
--- 4 condition withheld
- Total high-hazard dams: 4
- Number potentially dangerous: 3 (75.0%)
- Potentially dangerous dams include:
--- 3 not rated
- Total high-hazard dams: 4
- Number potentially dangerous: 3 (75.0%)
- Potentially dangerous dams include:
--- 3 in poor condition

- Total high-hazard dams: 1
- Number potentially dangerous: 1 (100.0%)
- Potentially dangerous dams include:
--- 1 in poor condition

- Total high-hazard dams: 1
- Number potentially dangerous: 1 (100.0%)
- Potentially dangerous dams include:
--- 1 condition withheld

- Total high-hazard dams: 1
- Number potentially dangerous: 1 (100.0%)
- Potentially dangerous dams include:
--- 1 condition withheld

- Total high-hazard dams: 1
- Number potentially dangerous: 1 (100.0%)
- Potentially dangerous dams include:
--- 1 condition withheld

- Total high-hazard dams: 1
- Number potentially dangerous: 1 (100.0%)
- Potentially dangerous dams include:
--- 1 condition withheld

- Total high-hazard dams: 1
- Number potentially dangerous: 1 (100.0%)
- Potentially dangerous dams include:
--- 1 condition withheld
- Total high-hazard dams: 1
- Number potentially dangerous: 1 (100.0%)
- Potentially dangerous dams include:
--- 1 condition withheld

- Total high-hazard dams: 1
- Number potentially dangerous: 1 (100.0%)
- Potentially dangerous dams include:
--- 1 not rated

- Total high-hazard dams: 1
- Number potentially dangerous: 1 (100.0%)
- Potentially dangerous dams include:
--- 1 in poor condition

- Total high-hazard dams: 1
- Number potentially dangerous: 1 (100.0%)
- Potentially dangerous dams include:
--- 1 in poor condition

- Total high-hazard dams: 1
- Number potentially dangerous: 1 (100.0%)
- Potentially dangerous dams include:
--- 1 condition withheld
- Total high-hazard dams: 3
- Number potentially dangerous: 3 (100.0%)
- Potentially dangerous dams include:
--- 3 condition withheld

- Total high-hazard dams: 3
- Number potentially dangerous: 3 (100.0%)
- Potentially dangerous dams include:
--- 3 condition withheld

- Total high-hazard dams: 3
- Number potentially dangerous: 3 (100.0%)
- Potentially dangerous dams include:
--- 3 in poor condition

- Total high-hazard dams: 4
- Number potentially dangerous: 4 (100.0%)
- Potentially dangerous dams include:
--- 1 in poor condition
--- 3 condition withheld

- Total high-hazard dams: 9
- Number potentially dangerous: 9 (100.0%)
- Potentially dangerous dams include:
--- 9 condition withheld
This story features data reporting by Paxtyn Merten, writing by Dom DiFurio, and is part of a series utilizing data automation across 50 states.
