Eugene Sawyer Water Purification Plant

Gazing at the Eugene Sawyer Water Purification Plant, it’s hard to believe it was once the largest water purification plant in the world. Originally called the South Water Purification Plant, its construction began in 1930. The Great Depression slowed its progress, but finally, in 1947, the Eugene Sawyer Water Purification Plant opened its doors, or rather, its massive intake pipes. Think about this for a second. Two main cribs, submerged structures, sit about 2.5 miles offshore in Lake Michigan. They’re connected to the plant via tunnels running beneath the lakebed. The 68th Street/Dunne cribs are the source, drawing water from 20-30 feet below the surface. This water then makes its journey through the tunnels to the Eugene Sawyer Water Purification Plant, where a complex filtration process begins. The plant doesn’t rely on gravity. Powerful pumps push the water through various stages, removing suspended particles and adding disinfecting chemicals like chlorine. This process ensures clean, safe drinking water for millions in Chicago and surrounding suburbs, about one billion gallons every single day. The Eugene Sawyer Water Purification Plant held the “world’s largest” title until 1964 when Chicago’s Central District Filtration Plant, now known as the Jardine Water Purification Plant, came online. In 2016, the South Water Purification Plant was renamed to honor former Mayor Eugene Sawyer, recognizing his service to the city, which interestingly, began right here in the Water Department. Even today, the city continues to invest in the plant. In 2020, a $74.5 million renovation project commenced, focusing on restoring the roof of the original 1941 building and a later 1964 addition. The Eugene Sawyer Water Purification Plant stands as a testament to Chicago’s commitment to providing clean water for its citizens, a legacy built drop by carefully treated drop.