Imagine a structure rising from the lake like a fortress. That is the Harrison-Dever Water Intake Crib. It is a vital part of Chicago’s water system.
The Harrison-Dever Water Intake is not just one structure. It is two interconnected buildings. The older one is the Carter Harrison Crib. It was built in 1900. The other is the William E. Dever Crib completed in 1935. Both are named after former Chicago mayors.
Many Chicagoans call the Harrison-Dever Intake Crib the “Two-Mile Crib”. It sits two miles off the Chicago shoreline. But there is also a historical reason. The Carter Harrison Crib replaced an even older structure called “Two-Mile Crib”. It was built in 1865.
The Harrison-Dever Water Intake pumps water to Chicago. It uses a 20-foot diameter tunnel. This tunnel runs under the lake. It connects the crib to the James W. Jardine Water Purification Plant. The plant is just north of Navy Pier.
The Carter Harrison Crib almost did not make it to today. By 1930, there were already plans to replace the Harrison crib. The new Dever Crib was erected alongside the Harrison in 1935. With the Dever crib fully functional, the Harrison crib was taken out of operation in 1936. However, as water requirements in the city continued to grow, the Harrison crib was reactivated some time thereafter.
The water makes its way to the James W. Jardine Water Purification Plant. This plant processes nearly one billion gallons of water daily. The Jardine Plant and the South Water Purification Plant serve nearly five million consumers. This includes Chicago and 118 suburbs.
The filtration process takes up to seven hours. Water passes through chemical treatments. Additives like carbon, chlorine, and fluoride are added. Chlorine kills pathogens. Fluoride prevents tooth decay. The final steps include traditional filtration using gravel and sand.
Processed water is delivered through pumping stations. The plant drains and cleans the intake basins each spring. This ensures safe drinking water.
The Harrison-Dever Water Intake stands as a testament to Chicago’s engineering. It ensures clean water for millions. A crucial structure, it helps sustain the city.