Hyperion sewage treatment plant

[1] Los Angeles City Sanitation (LASAN) operates the largest wastewater collection system in the US, serving a population of four million within a 600 square miles (1,600 km2) service area.

Until 1925, raw sewage from Los Angeles was discharged untreated directly into Santa Monica Bay in the region of the Hyperion Treatment Plant.

[3] With the population increase, the amount of sewage became a major problem to the beaches, so in 1925 the city built a simple screening plant in the 200 acres (0.81 km2) it had acquired in 1892.

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.

[3] Marine life in Santa Monica Bay suffered from the continuous discharge of 25 million pounds (11 kt) 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.

View of the Hyperion Sewage Treatment Plant from the Marvin Braude Bike Trail
The Hyperion Water Reclamation Plant from the air
Detail of one of the plant buildings designed by Anthony J Lumsden , FAIA.
Water going through cleaning process at the Hyperion sewage treatment plant. A majority of the water can be reclaimed, and water that is not clean enough goes to the ocean.