Green business, green careers and job training
Solutions that build smart communities with green careers and businesses!

Save on Career Education through Lorman Education

Our readers are offered a discount on Lorman seminars and courses. Check out their business, management and legal offers at this link to qualify for our discounts. They also offer green business training opportunities. Please visit for a complete listing of courses. Register online or call Lorman at 866-352-9539.

The Importance of Decentralized Wastewater Management in the Twenty-First Century

Dr. Tchobanoglous’ early work on the use of wetlands for wastewater treatment culminated in the first national conference on the subject in 1979, and a variety of new filtration technologies have been approved for use in California in restrictive reclamation applications.

Find green business solutions
Dr. George Tchobanoglous has received wide recognition for his contributions to understanding modernized wastewater treatment options.

Decentralized wastewater management (DWM)

Given the important role that DWM can play in the protection of public health and the environment and in the management of water resources, this subject has not received the attention it deserves or requires. I hope, through the opportunities made possible by the Clarke Prize, to promote the critical role of DWM in protecting public health and the environment, and to promote long-term water sustainability in the twenty-first century. DWM may be defined as the collection, treatment, and reuse/dispersal of wastewater from individual homes, clusters of homes, isolated communities, industries, or institutional facilities at or near the point of waste generation.

To put the subject of DWM in perspective, it is useful to think about the following issues:

  • The need for and importance of DWM.
  • Opportunities for water reuse and their potential impact on sustainability.
  • The status of DWM technologies for wastewater treatment and reuse.
  • New management strategies that must be developed.
  • Challenges that must be faced and overcome in implementing DWM systems.

The Best Laid Plans for Complete Sewage Service in the US

With the passage of the Clean Water Act in the early 1970s, it was reasoned that it was only a matter of time before sewerage facilities would be available to almost all residents of the continental United States. Now, more than 30 years later, it is recognized that the complete sewerage of the United States may never be possible due to geographic and economic constraints.

At present, more than 60-million people in the United States live in homes where individual decentralized systems (most typically comprised of a septic tank and leachfield) are used for wastewater management. Many of the existing systems need to be upgraded and all should be managed.

If localized water reuse is to gain acceptance, effective DWM systems must be used to create a paradigm shift from effluent disposal (“wastewater is a problem”) to water reuse (“wastewater is a resource”).

Historically, wastewater treatment plants were located in remote areas, typically near rivers or the ocean. In the intervening years, the area surrounding most wastewater treatment plants has developed to the extent that the localized reuse of large quantities of treated effluent at or near the treatment plant site is often no longer feasible.

Unfortunately, building new pipelines to transport treated wastewater to locations where it can be reused beneficially has proven to be prohibitively expensive. Concurrently, in many locations, the available dilution capacity in the receiving water body is no longer sufficient to meet the needs of future growth. In these locations, DWM systems can be used effectively to bring about localized reuse and to reduce the quantity of wastewater discharged to centralized wastewater treatment facilities.

Local Water Reuse Opportunities

The utilization of water from local sources will depend on available reuse opportunities and their corresponding water-quality requirements.

Worldwide, the most common use of reclaimed wastewater has been for agricultural and landscape irrigation. Other reuse opportunities include industrial uses, groundwater recharge, recreational/environmental, nonpotable urban uses (Figure 2), and indirect potable use. For the short-term, landscape irrigation will continue to be the principal reuse option for individual decentralized systems in urban areas.

In many metropolitan areas, building codes for new commercial and industrial facilities now require the installation of dual plumbing. Reclaimed water for toilet flushing in these facilities would be provided most economically by treatment facilities located within the building complex (the practice in Tokyo, Japan) or nearby. Wastewater to be treated would be mined (extracted) from the wastewater collection system.

To maximize the reuse of larger quantities of treated wastewater at or near the point of generation, the use of satellite reclamation plants connected to collection systems for sludge processing (as in Los Angeles County, California, for their upstream reclamation plants) will continue to increase in the future.

California Wastwater Expert: Dr. George Tchobanoglous

George Tchobanoglous,Ph.D.,p.E., Professor Emeritus, Department of Civil and Environmental Engineering, University of California, Davis has received recognition for his contributions to understanding modernized wastewater treatment options.

Wastewater expert Dr. George Tchobanoglous has made significant contributions to the practice of environmental engineering through his research, publications, public service, and international activities. He is widely recognized for advancing the use of new technologies in four key areas: constructed wetlands for wastewater treatment, the application of alternative filtration technologies, ultraviolet (UV) disinfection for wastewater reuse applications, and decentralized wastewater management.

Dr. Tchobanoglous’ early work on the use of wetlands for wastewater treatment culminated in the first national conference on the subject in 1979. Based on his filtration research, a variety of new filtration technologies have been approved for use in California in restrictive reclamation applications. His successful studies on UV radiation have brought about the widespread acceptance of UV disinfection in water reuse applications. As Chair of NWRI’s UV committee, he helped draft the first UV guidelines for water reuse in 1993. Recognized as an expert on decentralized wastewater management systems, he has been asked to be a keynote speaker at more than 15 conferences in the past 3 years.

Perhaps Dr. Tchobanoglous’ greatest impact has been in the training of environmental engineers. He is the author or coauthor of over 350 publications, including 12 textbooks and three reference books. The textbooks have been used at more than 225 colleges and universities in the United States, as well as at universities worldwide, both in English and in translation. His books are famous for successfully bridging the gap between academia and the day-to-day world of the engineer. Notably, his textbook, Wastewater Engineering: Treatment, Disposal, Reuse, now in its fourth edition, is one of the most widely read textbooks in the environmental engineering field by both students and practicing engineers.

Download the report

Edited by Carolyn Allen
| wastewater | recycling | Los Angeles |


Related Articles

Innovations wanted for LAUNCH: Beyond Waste

LID (Low Impact Development) Coming to Los Angeles

Phosphorous Becomes a Sustainability & Recycling Issue

Career Resources

We encourage lifelong learning to support sustainable communities and provide these select resources to help you pursue green and sustainable self-development:

Lorman Business Training Directory of On-line Business and Compliance Classes

Job & Career Resources

Sales & Marketing
Human Resources
About Us ~ Privacy Policy

California Green Solutions is a publication of Carolyn Allen ~ Copyright ©2006-2030 Carolyn Allen

B2B | Green Directory | Remodeling |
CONSUMERS | Backyard Nature | Senior Health | MultiMedia Marketing | Marketing |