Figure 1. Calumet Area Water Supply Pollution Threat Prior to 1922.

Figure 2. Sag Valley West, 1901.

Figure 3. Calumet Rivers, 1901.

Figure 4. Calumet Rivers East, 1901.

Figure 5. Calumet Rivers & Railroads, 1901.

Figure 6. Calumet-Sag Channel Route West Section.

Figure 7. Calumet-Sag Channel Route West Central Section.

Figure 8. Calumet Sag-Channel Route East Central Section.

Figure 9. Calumet-Sag Channel Route East Section.

Figure 10. Calumet-Sag Channel Route and Stony Creek.

Figure 11. Wabash Railroad in 1914, Old and New Right-of-Way Crossing the Sag Valley.

Figure 12. Calumet River Straightening.

Figure 13. Little Calumet River Improvement.

Figure 14. Chicago Sewers, 1908.

Figure 15. Calumet Intercepting Sewer Section 17F.

Figure 16. Hazel Crest & Markham Sewers.

Figure 17. Calumet Sewage Treatment Works, 1922.

Figure 18. Calumet Sewage Treatment Works, 1936.

Figure 19. Second Calumet Plant Connections.

Figure 20. Calumet Plant Details.

Figure 21. Cal-Sag Watershed.

Figure 22. Little Calumet River Watershed.

Figure 23. Calumet Deep Tunnel.

Figure 24. Upper Des Plaines Deep Tunnel.

Figure 25. Schematic Representation of Self-Purification of the Waters between the Chicago River and the Mississippi River, 1900–1901.

Figure 26. Area Diverted from Lake Michigan Watershed.