Hyperion sewage treatment plant
The Hyperion Water Reclamation Plant is located in southwest Los Angeles, California, next to Dockweiler State Beach on Santa Monica Bay. The largest sewage treatment facility in the Los Angeles Metropolitan Area, Hyperion is operated by the City of Los Angeles, Department of Public Works, Bureau of Sanitation.
Until 1925, raw sewage from the city of Los Angeles was discharged untreated directly into Santa Monica Bay in the region of today's Hyperion Treatment Plant.
With the population increase, the amount of sewage became a major problem to the beaches, so in 1925 the city of Los Angeles built a simple screening plant in the 200 acres (0.81 km2) the city had acquired in 1892.
Even with the screening plant, the quality of the water in Santa Monica Bay was unacceptable, and in 1950 the city of Los Angeles opened the Hyperion Treatment Plant with full secondary treatment processes. In addition, the new plant included capture of biogas from anaerobic digesters to produce heat dried fertilizer.
In order to keep up with the increase of influent wastewater produced by the ever growing city of Los Angeles, by 1957 the plant engineers had cut back treatment levels and increased the discharge of a blend of primary and secondary effluent through a five-mile (8 km) pipe into the ocean. They also opted to halt the production of fertilizers and started discharging digested sludge into the Santa Monica Bay through a seven-mile (11 km) pipe.
Marine life in Santa Monica Bay suffered from the continuous discharge of 25 million pounds of sludge per month. Samples of the ocean floor where sludge had been discharged for 30 years demonstrated that the only living creatures were worms and a hardy species of clam. Additionally, coastal monitoring revealed that bay waters often did not meet quality standards as the result of Hyperion's effluent. These issues resulted in the city entering into a consent decree with the United States Environmental Protection Agency and the California State Water Resources Control Board to build major facility upgrades at Hyperion. In 1980, the city launched a massive "sludge-out" project which upgraded the plant to full secondary treatment. Sludge digesters are used to destroy the disease-causing organisms (pathogens). The sludge-out portion of the program was completed in 1987.
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