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| TRACKING DOWN THE ROOTS OF OUR SANITARY SEWERS |
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PUMPING OF SEWAGE
Steam-driven pumping equipment was first developed/implemented for wastewater facilities in the early 1800s. Since few comprehensive sewerage systems existed early on in the United States, pumps were often not needed for conveying sewage. One of the earliest sewage pumping systems (steam-driven) was designed and constructed as part of Boston's main drainage works in 1884. Not long thereafter, the pumping of sewage was also implemented via the installation of major pumping plants in the sewage conveyance systems of Washington, D.C., Baltimore, Chicago, and New Orleans. The early pumping stations used steam-driven plunger pumps, then steam-driven centrifugal pumps; in the early 1900s, electric-motor-driven pumps came into being. Screw pumps evolved for lifts of a few feet, such as for lifting lake water to further dilute otherwise polluted streams/rivers (Chicago and Milwaukee). In New Orleans, large screw pumps were installed for pumping storm run-off water out of the low-lying city into the Mississippi River. The design and capabilities of pumping systems continued to evolve on into the 1900s, with applications to large and small systems alike. In the late 1800s and the early 1900s, the choices of power for pumping systems included steam, gas, gasoline, and hot air; in each of these choices, a complete power-generating plant was needed at each pump station. When electricity became available as the driving force, only the motor and the pump were required. Types of pumps, in the early years, ranged from the piston or plunger pumps to centrifugal pumps. Although some screw pumps were used in the early years, they generally did not meet with initial widespread success. The centrifugal pumps required a rather constant volume of sewage, thus requiring a storage basin at the pumps' suction. Piston pumps usually required the sewage to be screened prior to pumping to reduce the probability of damage to the pump. Overall, centrifugal pumps began to be favored. The Shore Ejector was developed for lifting sewage; it was operated with
compressed air supplied from a nearby air compressor station. Such devices
were often utilized in situations wherein a large number of pumps in a
particular area were needed -- this simpler device was easier (being powered
from one centralized source of compressed air) to implement than several
of the other types of pumping systems, which each required their own power
production unit. Portsmouth, VA; Winona, MN; and Santa Cruz, CA, utilized
Shore Ejectors in the early years. |