Hyperion Water Reclamation Plant

In the late 1800s, wastewater from Pueblo de Nuestra Senora la Reina de Los Angeles was conveyed through natural waterways to the ocean. In 1892, the City purchased 200 acres of oceanfront property and from 1894 until 1925, raw sewage was discharged into near-shore ocean waters at Hyperion's future location.

Visitors to local beaches objected to raw sewage in their recreational waters and in response, the City of Los Angeles built and started operating the first treatment facility at the Hyperion site in 1925: a simple screening plant. This plant remained in operation until 1950.

The screening plant was not effective in preventing beach closures; highly polluted wastewater was still being discharged into near-shore waters.

Just after the end of World War II, the City began to develop plans for a full secondary treatment plant at the Hyperion site. When the new Hyperion Water Reclamation Plant opened in 1950, it included a full secondary treatment system and biosolids processing to produce a heat-dried fertilizer. It was among the first facilities in the world to capture energy from biogas by operating anaerobic digesters, which have yielded a fuel gas by-product for over 50 years. At the time, Hyperion was the first large secondary treatment plant on the West Coast and one of the most modern facilities in the world.

In the 1950s, the population of Los Angeles grew dramatically. To keep up with this growth and the associated high wastewater flows, Hyperion's treatment levels were cut back. By 1957, the new plant was discharging a blend of primary and secondary effluent through a five-mile ocean outfal. Hyperion also stopped its biosolids-to-fertilizer program and began discharging digested sludge into Santa Monica Bay through a separate, seven-mile ocean outfall.

In the 1950s, the population of Los Angeles grew dramatically. To keep up with this growth and the associated higher wastewater flows, Hyperion's treatment levels were cut back. By 1957, the new plant was discharging a blend of secondary and primary effluent through a five-mile ocean outfall. Hyperion also stopped its biosolids-to-fertilizer program and began discharging digested sludge into Santa Monica Bay through a separate, seven-mile ocean outfall.

Further improvements at Hyperion are being planned and built to keep the plant on the leading edge of environmental protection. For example, the Digester Gas Utilization Project (DGUP) will reduce the environmental impacts of power and steam generation and utilize Hyperion's digester gas for renewable energy generation.

Wastewater comes to the City's water reclamation and treatment facilities via the sewer system. Most of it comes from inside houses - from sinks, dishwashers, bathtubs, toilets and washing machines. Some of the water that is treated comes from commercial and industrial users.

Headworks
The first place the wastewater arrives at in the water reclamation and treatment plants is the Headworks area. The initial  materials removed from wastewater are the most noticeable ones like wood, sticks, plastic and rags. Bar screens let the liquid flow through but stop the big objects. Sedimentation tanks are then used to capture sand and other gritty solids. Fifteen tons of these solids are removed and driven to landfills every day. Wastewater then continues to primary treatment.

Primary Process
Most of the solids are removed here after they sink to the bottom of covered, underground tanks and are pumped to the digesters. The tanks are covered to reduce odors. Other wastes are skimmed from the surface. The liquid is then pumped to the secondary treatment system for further treatment.

Secondary Treatment
Bacteria is added to the aeration tanks for the nitrification-denitrification process. The bacteria feed off the organic wastes in the wastewater. Oxygen is added in the nitrification process to speed up the bacteria’s rate of decomposition. The nitrification-denitrification process reduces the amount of nitrogen in the plant’s effluent. The wastewater, rich in activated sludge, then flows to the secondary clarifiers.

Clarifying Tanks
The second stage of secondary treatment involves the settling of activated sludge by gravity in the final settling tanks, or secondary clarifiers. A portion of this settled activated sludge is returned to the aeration tanks (returned activated sludge, or RAS) to maintain biological equilibrium in the aeration tank, while the remaining portion is discharged/wasted (waste activated sludge, or WAS) to the sewer. All of the waste activated sludge flows to the Hyperion Water Reclamation Plant for further processing. Once at Hyperion most of the sludge is sent to the oxygen reactors to continue biological treatment.

Tertiary Treatment
After secondary treatment, the wastewater flows through diamond-shaped cloth filters to remove any remaining solids. To improve filtering, a cationic polymer is used as a coagulant to capture and remove any remaining colloidal-sized solids.

Digestion
Again, we call on Mother Nature to help us, this time to destroy the disease causing organisms (pathogens) in the biosolids. The solids that were removed from primary and secondary treatment are now pumped into huge, totally enclosed, egg shaped tanks called digesters. Bacteria and other microorganisms that live without oxygen thrive here. It takes about 15 days for these microorganisms to eat half of the biosolids, destroy the pathogens and release a natural methane gas that has tremendous energy value.

Dewatering
The biosolids are very wet when they leave the egg shaped digester. To lower transportation costs, we reduce the amount of water in the biosolids by sending them through a centrifuge which acts like the spin cycle of a washing machine and removes one-fourth of the water.

Land Use
Biosolids are nutrient-rich organic materials that are very valuable to farmers and others who need amendments and composts to improve their soil.

The City owns a 4,688-acre farm site, Green Acres Farm in Kern County, where 99.9% of the biosolids are applied. Non-food crops such as corn, wheat, and alfalfa are grown on the farm. Class A is the required standard for applying biosolids in Kern County and Terminal Island's product exceeds that quality level. Other biosolids are mixed with green waste and zoo wastes and used as landscape compost or for non-food agricultural applications.

We are pleased to provide free group tours of our water reclamation facilities. On the tours, you will learn what happens to everything that goes down the drain in homes and businesses.

Sewage contains mostly water and solids. As you go through the tour, notice that many of the treatment processes at the plants are designed to separate solids from water. This must take place so that when the wastewater is completely treated it is clean enough to be pumped into a body of water or recycled for other uses.

The solids have value, too. They are sent back into the sewer system and flow to the Hyperion Water Reclamation Plant where they are processed into energy resources, soil amendments and fertilizer.

Due to security constraints, tours are available by appointment only. To schedule a tour, please call 310-648-5363.