August 26, 1908: Municipal Journal and Engineerarticle. Wet Excavation of a Sewer Trench. “At Gary, Ind., where two years ago was prairie is today a city of 15,000, with ten miles of paved streets, twenty miles of gas mains, electric light plant, telegraph and telephone service. To complete the list of public services a sewerage system is now nearing completion, which will contain about twenty miles of mains and cost about $350,000. Several details of this system contain novel features, but one of the most interesting is the method employed by the contractors, Green & Sons, of Chicago, in trenching through a swamp underlaid with so-called quicksand. This trench was approximately 30 feet deep, 22 feet below the level of the ground water. The material excavated is said to be so saturated that an excavation in it one foot deep will take a width of thirty feet. The ground is in several places very low and contains ponds three or four feet deep. These conditions made ordinary methods impossible.
The contractors accordingly adopted a method novel in many respects. The upper eight feet, more or less, down to ground water, were excavated by means of a scraper bucket elevator, the width being made greater than that of the trench proper and no sheeting being used. Following this, a pump and series of connected wells in a double line in the center of the trench were used along 132 feet of the trench to remove the ground water to a depth of something less than sixteen feet. After this the trench was excavated in twenty-two-foot sections, sheeting being driven meantime to a further depth of six feet. Pump No. 1 was then moved ahead, and two others were set up, connected to wells dose to the sheeting on each side, and the excavation was then carried about sixteen feet deeper and the brick sewer built. In Boston and other places the method of drying the soil by numerous pipe wells before excavation has been used, but there are several features of the Gary work which are new and the work as a whole is, we believe, of greater magnitude than those referred to.”
Commentary: It appears that Gary, Indiana sprang out of the ground as an industrial center complete with a city infrastructure. The most interesting thing about this article is the amazing photograph. As noted on the photo it was taken from the mast of a bucket excavator, presumably with a photographer in the bucket towering 30-40 feet about the ground.