Renewable energy and water reclamation are two of the hottest topics in the public infrastructure sector, particularly in California. For most governmental agencies, these topics have been especially pressing within the past 10 years, as drought conditions, stricter environmental laws, and increasing energy costs have become the norm in the “Golden State” during that time. 

The Sanitation Districts have long been concerned with these and other important environmental issues. The Sanitation Districts were formed in 1923, when many of the municipalities surrounding Los Angeles sought to handle their own wastewater conveyance, treatment and disposal. Solid waste management responsibilities were added in 1957, after Los Angeles County’s Board of Supervisors banned the burning of refuse by residents.

The agency was among the first of its kind to embrace the use of alternative energy sources such as the reuse of digester gas produced during wastewater treatment. The Sanitation Districts began re-using digester gas to power engines in its treatment facilities in the 1930s. During the 1970s, the agency was one of the first to collect and re-use landfill gas. “We’ve always tried to be innovative in the ways we serve residents, and have sought to do new things, whether in our treatment processes, solid waste operations, or resource recovery efforts,” Assistant Chief Engineer Robert Ferrante says.

The Sanitation Districts are a confederation of 24 independent sanitation districts serving 5.5 million people in Los Angeles County. Each district operates as its own entity with a separate board of directors. The 24 individual districts work cooperatively with one another under a joint administration agreement with one administrative staff headquartered near Whittier, Calif.

The agency operates 10 water reclamation plants and one ocean discharge facility treating approximately 430 million gallons of water per day. The Sanitation Districts also manage a number of solid waste facilities, including landfills, materials recovery facilities, and waste-to-energy facilities. The service area, which covers approximately 850 square miles, encompasses 78 cities and unincorporated territory with the county.

The agency’s current renewable energy efforts include energy recovery facilities at both its wastewater and solid waste facilities, which utilize landfill or digester gas to produce electrical power and process heat in a variety of technologies, including turbines, boilers, and internal combustion engines.

The districts produce approximately 120 megawatts of electricity. This is enough power to meet the needs of about 170,000 Southern California homes. Some of the electricity is used to power Sanitation Districts’ operations; the rest is sold to local utilities.

Enhanced Capabilities

The Sanitation Districts continue to use technology to recycle and process wastewater and refuse. The agency is enhancing its solid waste recycling capabilities by adding conveyor belt sorting systems that will make it easier to divert recyclable material from its landfills. The Sanitation Districts are also conducting a research project in conjunction with Waste Management that is examining the re-use of ground-up food waste in digesters to produce methane gas for energy production, Ferrante notes.

The agency is also making improvements to its largest water reclamation facility, the San Jose Creek Water Reclamation Plant in Whittier, Calif. These improvements include adding flow storage tanks to help make more recycled water available for re-use when irrigation demands are greatest, especially important in drought-prone Southern California.  Currently, the agency provides more than 90 million gallons of recycled water per day (more than 100,000 acre-feet per year) for use at over 750 sites.

Work is also underway on a six-year, $600 million effort to add a third discharge tunnel to the Joint Water Pollution Control Plant in Carson, Calif. This will give the agency additional capacity and allow it to inspect and maintain its existing two tunnels, which were both constructed during the 1930s and 1950s.

A Can-Do Attitude

A staff of more than 1,700, included over 200 licensed engineers, oversees and operates all of the Sanitation Districts’ projects and facilities. “Our greatest strength is the diversity and technical expertise of our staff,” Ferrante says. “We’re not a typical government agency in that most of the work we do is done in-house, from planning and design to construction, operation, and monitoring. This allows us to be innovative and a leader in the field.”

The agency has a very high employee retention rate, which Ferrante attributes in part to its training and development programs as well as its promoting of staff from within. “We have a staff with a lot of experience and very good institutional knowledge,” he adds.

The agency emphasizes efficiency in all of its operations. “We want to benefit our ratepayers and our communities.” Ferrante says. “By constantly innovating, our agency has been able to provide cost-effective wastewater and solid waste management to our customers.”