Prepared in Cooperation with the Southern California Council on Environment and Development (SCCED) Water Task Force by Jim Stewart and Neal Shapiro
Summary:
Why We Should Recycle Water
Water recycling is:
Needed: To meet current and projected water demand, the SCAG region needs to fully exploit the locally-available potential for water reclamation.
Available: Water from existing water reclamation plants is readily available for recycling, but is not being fully used. Additional facilities can be built.
Safe: Recycled water is highly treated and disinfected, making it safe for all permitted uses, which are strictly regulated by state and local authorities.
Economical: Recycled water can be provided to users at less cost than imported water, plus it enhances the local economy by using a local resource.
Environmental: Recycled water is environmentally sound, reducing depletion of watersheds, saving energy and reducing air pollution.
Useful: Recycled water is used for many applications, including industrial processes, landscape irrigation, groundwater recharge, seawater intrusion barriers, environmental enhancement and recreation.
Acceptable: Government bodies, businesses and organizations have endorsed the use of recycled water.
Doable: Water recycling is prent throughout the world. In Southern California, a number of steps can help increase the use of recycled water.
The Need for Water Recycling in Southern California
About 75% of the state’s rain falls north of Sacramento, but 80% of the net water demand is south of Sacramento1. Therefore 6 million acre-feet per year (AFY) [an acre-foot = 325,851 gallons] must be moved from Northern California to Central and Southern California, plus another 5 million AFY are brought in from the Colorado River1, but still the demand is not met.2 The State Department of Water Resources predicts statewide shortfalls of up to 4.1 million AFY by the year 2010.1 The U.S. Bureau of Reclamation draft report on water use and reclamation has identified a shortage in Southern California of 0.23 million AFY in 1990, increasing to nearly 3 million AFY by 2040.3
The Metropolitan Water District (MWD) serves 85% of the population of the SCAG region plus the County of San Diego. The following table shows the actual sources (in millions of acre-feet per year) for MWD’s service area in fiscal year 1993-4 which was a “wet year.” The table also shows the MWD preferred resource mix projected for 2020 if it were a “dry year” (such as the severe drought in 1991), assuming the population of the MWD service area grows from the current 15.7 million to 21.5. (The drought year “supply” also includes 0.16 million AFY in drought management reductions, plus conservation practices.)
Sources 1993-4 2020 (if severe drought)
State Water Project (SWP) 0.82 1.37
Colorado River Aqueduct (CRA) 1.30 1.20
Los Angeles Aqueduct 0.21 0.21
Local Groundwater (wells) 1.03 1.64 (includes wells & dams, and
Surface Production (dams) 0.17 drawing from storage)
Groundwater Recovery 0.003 0.05
MWD Storage & Transfers 0.45
Recycled Water (direct uses) 0.25 0.55
Total 3.78 5.47
However, there are some concerns about these projections, such as possible reductions in Colorado River water as more of the Central Arizona Project comes on-line. There are possible further reductions in the SWP from environmental concerns in the Delta. And there is always the possibility of future extended droughts.5
Groundwater is an important local source, supplying over 25% of our current needs, yet we are over-pumping the underground aquifers in SCAG’s rural areas.2 Because of past overdrafts in urban areas, about 50,000 AFY of freshwater must be injected back into the ground at key locations along the coast to keep the sea water from contaminating aquifers.6 There is additional storage capacity available in local aquifers, which could be recharged with recycled water as a protection against drought, which would also reduce the need to import distant fresh water for groundwater recharge.
Water reclamation is crucial for diversification of sources, to protect ourselves against any decrease in SWP or CRA supplies. The projections in the table for the year 2020 of 450,000 AFY from recycled water assumes the completion of currently planned projects. There could be substantially more if we as a society decided to fully utilitze water reclamation. (Note that the table includes as “groundwater” over 120,000 AFY in the Santa Ana River Recharge Project which is supplied by treated wastewater from San Bernardino and Riverside Counties.4)
Potential Sources for Recycled Water
The Draft Report by the U.S. Bureau of Reclamation is just completing a study of water use and reclamation in Southern California.3 They identified the total wastewater production in the SCAG region at over 1.6 million AFY in 1990, increasing to 2.5 million AFY in 2010. They believe all of this water could eventually be reclaimed (which could eliminate the need for any imports from the SWP, for example). This water source is also “drought resistant” because it flows independent of rainfall.
However, only a fraction of the wastewater is currently being recycled. For example, L.A. County Sanitation Districts process about 564,000 AFY, nearly all of which could be treated for recycling. In 1994-5, only 9% or 54,000 AFY was actively recycled, the rest sent to the ocean.7 Similarly, the City of Los Angeles Hyperion and Terminal Island Wastewater Treatment Plants discharge over 400,000 AFY of treated water into the ocean. None of the water from these plants was recycled in 1994-5. Two upstream treatment plants, Tillman and LA-Glendale, built specifically to be water reclamation plants, produced 86,240 AFY of reclaimed water, but only 22,900 AFY were re-used8; the other 95% of L.A. wastewater was discharged to the ocean. Half of the Las Virgenes Tapia Water Reclamation Facility is discharged to the ocean due to lack of off-season storage facilities.
The reasons for these ocean discharges include a lack of policy support for reclamation, insufficient piping to consumers and recharge basins, and state limitations on the amount of reclaimed water recharge allowed in certain groundwater basins.
There are a number of projects under construction or consideration which could substan-tially increase the amount of recycled water. The West Basin project, now beginning to recycle Hyperion water, is projected to reuse over 100,000 AFY by 2015. The L.A. Office of Water Reclamation 1990 study looked at long term options to utilize all of L.A.’s waste-water for purposes ranging from groundwater recharge to export for agricultural use.9
Another potential mean of recycling water is the use of gray water from households and businesses. With precautions, this can be recycled on site for landscape irrigation, reducing overall demand for fresh water.
Recycled Water Is Safe
Since state authorities already require tertiary treatment of wastewater before it can be discharged to local waterways (secondary treatment for ocean outfalls), effluent from the water reclamation plants in the SCAG area is safe and suitable for all purposes (except direct human consumption), including swimming, irrigation, and groundwater recharge.10 It is virtually micro-organism-free, containing less than the detection limit of bacteria. One agency, the L.A. County Sanitation Districts, found only one virus in 890 samples from 1979 – 1995,10 which is considerably better than normal drinking water. It is well below the health limits set for 46 metals and organic compounds in drinking water, as shown in the attached table.10
Another example of its safety is that most of the population of Orange County drinks groundwater recharged by the Santa Ana River, whose primary dry weather flow is from the treatment plants in San Bernardino and Riverside. In fact, the Santa Ana Watershed recycles 43% of its wastewater (nearly 200,000 AFY)11 through groundwater recharge or direct irrigation. Studies have shown that percolation through the soil in Southern California can easily purify treated recycled water and make it suitable for drinking. Thus using recycled water for groundwater recharge does not contaminate aquifers.10
Recycled Water is Economical
Because of subsidies from federal and state governments and from the MWD, recycled water is usually sold to consumers at a discount, ranging from 10% to 85% of the cost of imported potable water.10 A recycled water customer also does not have to pay the sewer charge, which is about $1.35 per 749 gallons in Los Angeles.4
In addition, local water reclamation projects provide local jobs and retain money, some of which would otherwise be used for purchase of foreign oil and out-of-state coal to produce electricity for pumping imported water.4 The L.A. County Sanitation Districts estimates that the 54,000 AFY it recycled in 1994-5 saved over 160 million kWhr of electricity (worth $6 million).7
Recycled Water is Environmental
The impact on fish and other wildlife caused by water transfers from Northern California has been the subject of much contentious debate; it is likely that the less transferred, the less impact on the environment of Northern California. In addition, energy is required to move the water such great distances. It takes about 30 times less energy to distribute local recycled water than to pump it in from Northern California.4 Every 100,000 AFY recycled avoids the release of 228 tons of pollutants that otherwise would have been caused by burning oil to produce the electricity for pumping.7
Another environmental benefit is using the nutrient or fertilizer content of secondary quality reclaimed water, which increases crop yields, reduces pollution from fertilizer run-off and saves the costs of adding chemical fertilizers, estimated at $20 to $45 per AF.4
Uses for Recycled Water
Water has been recycled for decades. The U.S. EPA reports Baltimore, Maryland, started supplying treated sewage water to industry in 1936.12 A California 1993 statewide survey of water reuse reported the following uses in thousands of AFY:13
Category Thousands of AFY Percentage
Groundwater Recharge 185 48%
Agriculture 80 21%
Landscaping & Parks 47 12%
Environmental Uses 29 8%
Industry 7 2%
Seawater Intrusion Barriers 7 2%
Miscellaneous 29 8%
Total 384 100%
All of these uses could be greatly increased.
Steps to Increase the Use of Recycled Water
Some of the ways to increase knowledge of, acceptance and implementation of recycled water use are:
1. Public policy statements by government bodies and water companies.
(See attached Statement of Support for Water Reclamation.14)
2. Analysis of water policies and costs and benefits to identify the best approaches to increase incentives for use of recycled water.
3. Expansion of integrated resources planning, as the MWD is already doing.
4. Education of business and industry on the urgency, safety and cost savings of recycling water themselves or by using recycled water from water districts.
5. Education of the public on the urgency, safety and cost savings of recycling water, especially for groundwater recharge. This could include media features, water bill stuffers, etc.
6. Education and incentives to encourage the installation of home gray water recycling systems, thus saving money and helping the environment. Laws and regulations requiring the use of gray water recycling systems in new businesses and housing developments.
7. Increased funds to expand recycling projects, especially using the output of the region’s Water Reclamation Plants to supply the various uses.
8. Integration of the agencies and the public into an improved regulatory review process.
9. Involve the public in all stages of project development through citizen advisory committees, public workshops, hearings and other review processes to facilitate recycling facilities’ acceptance by the public and rapid implementation.
10. Revision of the State Department of Health regulations which currently unrealistically limit the use of tertiary treated wastewater especially for groundwater recharge.
Endorsements of the Use of Recycled Water
Government bodies endorsing the use of recycled water include:
U.S. Environmental Protection Agency
U.S. Bureau of Reclamation
California Water Resources Control Board (January 6, 1977, resolution)
California Department of Water Resources
California Department of Health Services
Metropolitan Water District of Southern California
Orange County Grand Jury
L.A. Department of Water and Power
L.A. Department of Public Works
Orange County Water District
L.A. County Sanitation Districts
West Basin Metropolitan Water District
Central Basin Metropolitan Water District
Businesses endorsing or actively using recycled water include:
Los Angeles Area Chamber of Commerce
Chevron Oil
Mobil Oil
ARCO
UNOCAL
Tuftex Carpet Dying
Robertson Ready Mix
Water Gardens Commercial Complex in Santa Monica
Organizations endorsing the use of recycled water include:
California Conference of Directors of Environmental Health
WateReuse Association of California
Sierra Club
Heal the Bay
Mono Lake Committee
Surfrider Foundation
Audubon Society
TreePeople
In addition, many organizations (see attached list) have specifically endorsed the San Gabriel Valley recharge project, which is currently being opposed by the Miller Brewing Company.9
References for Footnotes
1 California Water Plan Update, Bulletin 160-93, California Department of Water Resources, October 1994.
2 California Water 2020, A Sustainable Vision, May 1995 (quoting Department of Water Resources estimates).
3 Southern California Comprehensive Water Reclamation and Reuse Study, Bureau of Reclamation, U.S. Department of the Interior, Draft Report, November 1995.
4 Regional Urban Water Management Plan for the Metropolitan Water District of Southern California, October 1995.
5 Water Resources Inventory in the City of Los Angeles, Neal Shapiro, 1995.
6 Estimate by Bahman Shiekh, West Basin Municipal Water District, 1995.
7 Annual Status Report on Reclaimed Water Use for Fiscal Year 1994-5, Sanitation Districts of Los Angeles County.
8 Urban Water Management Plan for the City of Los Angeles, Los Angeles Department of Water and Power, November 1995.
9 Water Reclamation in the Past: Opportunities and Plans for the Future, City of Los Angeles Office of Water Reclamation, January 1990.
10 Water Recycling in Los Angeles County, Earle Hartling, Sanitation Districts of Los Angeles County, 1995.
11 Santa Ana Watershed Project Authority, fiscal year 1994-5 data.
12 Guidelines for Water Reuse, U.S. Environmental Protection Agency, September 1992.
13 Survey of Future Water Reclamation Potential, WateReuse Association of California, July 1993.
14 Statement of Support for Water Reclamation, WateReuse Association of California, June 1994.