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Joint Administration Office of the Sanitation Districts of Los Angeles County


The Sanitation Districts protect public health and the environment through innovative and cost-effective wastewater and solid waste management, and in doing, so convert waste into resources such as recycled water, energy and recycled materials.


The Sanitation Districts function on a regional scale and consist of 24 independent special districts serving about 5.5 million people in Los Angeles County.  The service area covers approximately 824 square miles and encompasses 78 cities and unincorporated territory within the county.


The Sanitation Districts were created in 1923 when a significant number of cities were forming and it was clear that managing wastewater on a regional scale made sense.  The Sanitation Districts' purpose was to construct, operate, and maintain facilities that collect, treat, recycle, and dispose of domestic and industrial wastewater.  Individual districts operate and maintain the district-owned collection systems. Cities and unincorporated areas within a district are responsible for their smaller local collection systems.

Cities and unincorporated parts of the county are also responsible for the collection of solid waste.  In the 1950s, it became apparent that solid waste management would benefit from a regional approach.  At that time, the Sanitation Districts were given the responsibility to provide for the management of collected solid waste, including disposal and transfer operations, and materials and energy recovery.

To maximize efficiency and reduce costs, the 24 Sanitation Districts work cooperatively under a Joint Administration Agreement with one administrative staff headquartered near the City of Whittier.  Each Sanitation District has a Board of Directors consisting of the mayor of each city and the Chair of the Board of Supervisors for unincorporated territory.  Each Sanitation District pays its proportionate share of joint administrative costs.


Approximately 1,400 miles of sewers, 48 active pumping plants, and 11 wastewater treatment plants convey and treat about half the wastewater in Los Angeles County.  The Sanitation Districts’ solid waste management sites similarly provide about one-fourth of the countywide solid waste management needs.  The Sanitation Districts operate two sanitary landfills, two landfill energy recovery facilities, three materials recovery/transfer facilities, one recycle center, and participate in the operation of two refuse-to-energy facilities. 


Overall, wastewater and solid waste management budgets for 2016-17 are $609 million and $133 million, respectively.  Both systems provide their essential public services at some of the most competitive service charges in the country.


Seventeen of the Sanitation Districts in the metropolitan Los Angeles area are served by a regional, interconnected system of facilities known as the Joint Outfall System (JOS).  The JOS service area includes 73 cities and unincorporated territory, and small areas within the City of Los Angeles, Orange County, and San Bernardino County.

The JOS employs two main types of treatment plants.  Upstream water reclamation plants capture higher quality wastewater and convert it into a drought-proof water resource called recycled water.  Downstream, the Joint Water Pollution Control Plant (JWPCP) treats wastewater with a higher industrial contribution along with the solids removed at the upstream plants.  The JWPCP discharges its treated water to the ocean. 

This innovative configuration provides an efficient means to maximize recycled water production and its availability on a regional scale.  Treating wastewater for reuse is an important way that Southern Californians can maintain a high-quality of life in an otherwise arid land. 

There are six water reclamation plants (WRPs) in the JOS, which spans from Long Beach to La Cañada Flintridge and from the City of Los Angeles boundary to the Orange County line. 


Separate from the JOS, smaller regional wastewater systems are managed by the Sanitation Districts in the Santa Clarita Valley and the Antelope Valley.  Each of these valley areas are home to two WRPs that provide important sources of water for wildlife habitats and for municipal and agricultural reuse.

  • The Santa Clarita Valley Sanitation District operates the Saugus and Valencia WRPs. 
  • Sanitation Districts Nos.  14 and 20 serve the Antelope Valley.  Sanitation District No. 14 operates the Lancaster WRP, and Sanitation District No. 20 operates the Palmdale WRP. 


The Sanitation Districts are pioneers in using recycled water beneficially and remain strong proponents of expanding reuse options.  The WRPs produce a high-quality source of recycled water that essentially meets drinking water standards and is reused at more than 720 sites throughout the county.  Uses of recycled water include industrial, commercial, and recreational applications; groundwater recharge; and agriculture, landscape, park, and golf course irrigation.  Wastewater received at the JWPCP is higher in salts, making it more costly to recycle and reuse. 


500,000 tons of biosolids per year: that is how much the Sanitation Districts’ sewerage system produces as a byproduct of wastewater treatment.  The solids recovered from the treatment process are digested, producing a biogas that is converted to electricity or used for heating parts of the biological treatment process. As a result, the JWPCP is virtually energy self-sufficient. The digested solids, having undergone pathogen reduction, are beneficially reused through a variety of management options including reuse as a soil amendment for agriculture, and in the manufacture of high-quality compost.

Looking toward a sustainable future, the Sanitation Districts utilize two state-of-the-art composting facilities (see map below).  The Inland Empire Regional Composting Facility in Rancho Cucamonga is an entirely enclosed composting facility developed in a joint venture with the Inland Empire Utilities Agency.  The Tulare Lake Compost facility in Kings County will compost Sanitation Districts’ biosolids, along with the Central Valley’s agricultural waste using an engineered fabric cover composting system.

The Sanitation Districts operate a comprehensive solid waste management system serving the needs of a large portion of Los Angeles County.  This system includes sanitary landfills, recycle centers, materials recovery/transfer facilities, and energy recovery facilities.  In every operation, the first order of business is to ensure a “good neighbor policy” that strives for a harmonious balance with surrounding communities.


The Puente Hills Landfill, located near the City of Whittier, was one of the largest landfills in the nation.  Puente Hills pioneered the development of advanced environmental control systems that are now used at modern landfills throughout the state and nation.  These systems, designed to protect air quality and groundwater, include extensive landfill gas collection networks and underground liners.  Puente Hills Landfill closed permanently on October 31, 2013, after 43 years of operation.

The two other operational sites are the
Calabasas Landfill, located near the City of Agoura Hills, and the Scholl Canyon Landfill, located in the City of Glendale.  At the closed Spadra, Palos Verdes, and Mission Canyon landfills, the Sanitation Districts continue to maintain environmental control systems.


Among the first to utilize biogas as a natural resource to produce renewable energy, the Sanitation Districts’ energy recovery facilities at the Puente Hills, Spadra, and Calabasas landfills provide reliable and economic electrical power to help serve Southern California’s increasing energy needs. 

The use of solid waste as a fuel to produce power reduces our reliance on fossil fuels while helping to prolong the remaining landfill capacity in the region.  The Commerce Refuse-to-Energy Facility was the first of its kind in California.  It is owned by a Joint Powers Authority (JPA) created by the Sanitation Districts and the City of Commerce and is operated by the Sanitation Districts.  Similarly, the Southeast Resource Recovery Facility (SERRF) in Long Beach is owned by a JPA consisting of the Sanitation Districts and the City of Long Beach, and is operated by a private company.


As the list of recyclables continues to grow, the Sanitation Districts are deploying new, more sophisticated technology to maximize cost-efficiency.  In fact, the Sanitation Districts own and operate facilities that help Los Angeles County meet its goals in diverting waste from landfills and in providing cost-effective transfer of municipal solid waste to landfills by truck or rail.

The recycle centers located at the Puente Hills and Palos Verdes landfills are Certified California Buy Back Centers.  The Puente Hills Materials Recovery Facility (MRF) and the Downey Area Recycling and Transfer (DART) Facility recover recyclable materials, such as paper and plastics, through a combination of manual and mechanical methods.  The South Gate Transfer Station removes easily recoverable materials and reduces operational costs by consolidating smaller loads into larger ones for transport to landfills.


The pioneering spirit is again apparent as the Sanitation Districts take the lead role in implementing the Waste-by-Rail system, the transport of waste to distant disposal facilities by train.  This innovative system will provide long-term disposal capacity to replace local landfills as they reach capacity and close.

Puente Hills MRF was the initial infrastructure for the Waste-by-Rail system.  To further develop the system, the Sanitation Districts have completed construction of the Mesquite Regional Landfill in Imperial County (see map below), which is permitted to handle up to 20,000 tons per day for approximately 100 years.  Construction of the Puente Hills Intermodal Facility is now underway and will be ready by the time Waste-by-Rail is needed.


The Sanitation Districts are leaders in the production of green energy and the recycling of water and materials.  The following are just a few of our accomplishments:

  • Approximately 120 megawatts (MW) of electricity are generated in Sanitation Districts’ wastewater and solid waste operations.  In total, the Sanitation Districts produce power equivalent to the needs of about 160,000 Southern California homes.  Generation was increased with a new gas-to-energy facility at the Calabasas Landfill in 2010.  Some of the electricity is used in powering Sanitation Districts’ operations; the rest is used to reduce the amount of power produced by utilities, thereby reducing greenhouse gas emissions. 


  • The JWPCP uses biogas to generate 20 MW of electricity, making the facility virtually energy self-sufficient and saving approximately $17 million per year in avoided electrical costs.  Excess electricity is sold to the local power grid.


  • The Sanitation Districts have been leaders in energy efficiency at wastewater treatment plants for decades.  Technologies such as fine bubble diffusion, variable speed drives, high-efficiency motors, and automated control systems have allowed the Sanitation Districts to save millions of dollars in power costs.


  • Gas-to-Energy Facilities: Biogas, generated during the decomposition of organic material managed in landfills, is used to generate electricity.  At the Puente Hills Landfill alone, enough electricity is generated to power almost 70,000 Southern California homes.  Most of this power is sold to the local power grid, with the remainder used at the nearby San Jose Creek Water Reclamation Plant

  • Commerce Refuse-to-Energy Facility and SERRF:  These facilities utilize controlled combustion to convert refuse to electricity—enough to power approximately 55,000 Southern California homes.  Sophisticated air pollution control devices make these facilities some of the cleanest of their type in the world. 


The Sanitation Districts invite you or your school or organization to tour one of our facilities.  If you would like to book a tour or obtain additional information, please call (562) 908-4288, extension 2300.