Risky reservoirs: Illinois counties where aging dams pose the greatest threat

Charles Brutlag // Shutterstock

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

#50. Menard County
Kenneth Keifer // Shutterstock

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

#49. Cumberland County
Canva

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

#48. Putnam County
Roberto Galan // Shutterstock

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

#47. Alexander County
Kent Raney // Shutterstock

- Total high-hazard dams: 2
- Number potentially dangerous: 2 (100.0%)
- Potentially dangerous dams include:
--- 2 condition withheld

#46. Rock Island County
Canva

- Total high-hazard dams: 2
- Number potentially dangerous: 2 (100.0%)
- Potentially dangerous dams include:
--- 2 condition withheld

#45. Macon County
Canva

- Total high-hazard dams: 2
- Number potentially dangerous: 2 (100.0%)
- Potentially dangerous dams include:
--- 2 condition withheld

#44. Ogle County
Roberto Galan // Shutterstock

- Total high-hazard dams: 2
- Number potentially dangerous: 2 (100.0%)
- Potentially dangerous dams include:
--- 2 condition withheld

#43. Coles County
Canva

- Total high-hazard dams: 2
- Number potentially dangerous: 2 (100.0%)
- Potentially dangerous dams include:
--- 2 condition withheld

#42. Stephenson County
Canva

- Total high-hazard dams: 2
- Number potentially dangerous: 2 (100.0%)
- Potentially dangerous dams include:
--- 2 condition withheld

#41. Randolph County
Canva

- Total high-hazard dams: 2
- Number potentially dangerous: 2 (100.0%)
- Potentially dangerous dams include:
--- 2 condition withheld

#40. Logan County
Canva

- Total high-hazard dams: 2
- Number potentially dangerous: 2 (100.0%)
- Potentially dangerous dams include:
--- 2 condition withheld

#39. Saline County
Canva

- Total high-hazard dams: 2
- Number potentially dangerous: 2 (100.0%)
- Potentially dangerous dams include:
--- 2 condition withheld

#38. Jo Daviess County
Canva

- Total high-hazard dams: 2
- Number potentially dangerous: 2 (100.0%)
- Potentially dangerous dams include:
--- 2 condition withheld

#37. Richland County
Canva

- Total high-hazard dams: 2
- Number potentially dangerous: 2 (100.0%)
- Potentially dangerous dams include:
--- 2 condition withheld

#36. White County
Canva

- Total high-hazard dams: 2
- Number potentially dangerous: 2 (100.0%)
- Potentially dangerous dams include:
--- 2 condition withheld

#35. Washington County
Canva

- Total high-hazard dams: 2
- Number potentially dangerous: 2 (100.0%)
- Potentially dangerous dams include:
--- 2 condition withheld

#34. Cass County
Eddie J. Rodriquez // Shutterstock

- Total high-hazard dams: 2
- Number potentially dangerous: 2 (100.0%)
- Potentially dangerous dams include:
--- 2 condition withheld

#33. Marshall County
Canva

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

#32. McHenry County
Canva

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

#31. Sangamon County
Canva

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

#30. DeKalb County
Canva

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

#29. Marion County
Canva

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

#28. Union County
Canva

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

#27. Mason County
Canva

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

#26. McLean County
Canva

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

#25. Adams County
Canva

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

#24. Knox County
Canva

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

#23. Jefferson County
Jason Patrick Ross // Shutterstock

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

#22. Clinton County
David Huffman // Shutterstock

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

#21. Monroe County
Canva

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

#20. Christian County
Canva

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

#19. Fulton County
Roberto Galan // Shutterstock

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

#18. Hamilton County
Kristen Prahl // Shutterstock

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

#17. Schuyler County
Henryk Sadura // Shutterstock

- Total high-hazard dams: 5
- Number potentially dangerous: 5 (100.0%)
- Potentially dangerous dams include:
--- 5 condition withheld

#16. Tazewell County
Canva

- Total high-hazard dams: 6
- Number potentially dangerous: 6 (100.0%)
- Potentially dangerous dams include:
--- 6 condition withheld

#15. DuPage County
marythebarberphotos // Shutterstock

- Total high-hazard dams: 6
- Number potentially dangerous: 6 (100.0%)
- Potentially dangerous dams include:
--- 6 condition withheld

#14. Franklin County
Canva

- Total high-hazard dams: 6
- Number potentially dangerous: 6 (100.0%)
- Potentially dangerous dams include:
--- 6 condition withheld

#13. Bureau County
Canva

- Total high-hazard dams: 7
- Number potentially dangerous: 7 (100.0%)
- Potentially dangerous dams include:
--- 7 condition withheld

#12. Will County
Canva

- Total high-hazard dams: 7
- Number potentially dangerous: 7 (100.0%)
- Potentially dangerous dams include:
--- 7 condition withheld

#11. Kane County
Canva

- Total high-hazard dams: 7
- Number potentially dangerous: 7 (100.0%)
- Potentially dangerous dams include:
--- 7 condition withheld

#10. Winnebago County
Canva

- Total high-hazard dams: 7
- Number potentially dangerous: 7 (100.0%)
- Potentially dangerous dams include:
--- 7 condition withheld

#9. Peoria County
Canva

- Total high-hazard dams: 7
- Number potentially dangerous: 7 (100.0%)
- Potentially dangerous dams include:
--- 7 condition withheld

#8. LaSalle County
Canva

- Total high-hazard dams: 7
- Number potentially dangerous: 7 (100.0%)
- Potentially dangerous dams include:
--- 7 condition withheld

#7. Jackson County
Canva

- Total high-hazard dams: 8
- Number potentially dangerous: 8 (100.0%)
- Potentially dangerous dams include:
--- 8 condition withheld

#6. Macoupin County
Canva

- Total high-hazard dams: 8
- Number potentially dangerous: 8 (100.0%)
- Potentially dangerous dams include:
--- 8 condition withheld

#5. Montgomery County
Canva

- Total high-hazard dams: 10
- Number potentially dangerous: 10 (100.0%)
- Potentially dangerous dams include:
--- 10 condition withheld

#4. Lake County
Canva

- Total high-hazard dams: 12
- Number potentially dangerous: 12 (100.0%)
- Potentially dangerous dams include:
--- 12 condition withheld

#3. Madison County
Canva

- Total high-hazard dams: 15
- Number potentially dangerous: 15 (100.0%)
- Potentially dangerous dams include:
--- 15 condition withheld

#2. Cook County
Canva

- Total high-hazard dams: 16
- Number potentially dangerous: 16 (100.0%)
- Potentially dangerous dams include:
--- 16 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.

#1. St. Clair County
MShipphoto // Shutterstock