They Show Their Stuff
Some time after midnight, City Engineer Roy W. Morse sprang into action. He contracted with the Western Bridge Company, which had men and machines on site within hours. First they attempted to build a cofferdam, but this had to be abandoned, with the loss of a large mobile crane narrowly averted. Working around the clock, they then built a bypass sewer through Ravenna Park. This involved the building of a cofferdam at Brooklyn Avenue and Ravenna Boulevard, obtaining 5,400 feet of welded steel by-pass pipeline (from Seattle Water Department stocks of used pipe), and installing pumps. Service was restored by November 22, 1957.
Repairing the original brick sewer, which had been built in quicksand, presented severe technical difficulties and took months to complete. The quicksand had to be made stable and hard before it could be tunneled through. After trying several techniques that didn't work, project engineer Robert Burns proposed the Joosten Process. A modified form of this process finally worked to harden the sand. Sodium silicate (water glass) and calcium chloride were injected into the sand using high-pressure grease guns. This made the quicksand into a stable hard sand cocoon that could be tunneled into.
Nightmare Pothole Filled
The pit in Ravenna Boulevard caused by the cave-in was filled with 16,000 cubic yards of fill, brought in by barge from Steilacoom, trucked from barge to hopper, and then conveyed by conveyer belt from 17th Avenue NE to the center of the hole. Filling took 10 days.
The entire cost of repairing the cave-in of the Ravenna Trunk Sewer was $2 million. The work took two years to complete.