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 Research
Highlights - October 2004
Water--the Resource
With Many Lives
 Unlike
some of earth’s other natural resources, water has many
potential lives. After serving a primary function in urban or
agricultural settings, water may be reclaimed, treated to meet
a desired degree of purity, and reused for many nonpotable (nondrinking)
purposes. These might include the maintenance of golf courses,
highway medians, or office parks. Many communities use reclaimed
wastewater in utility cooling towers and manufacturing processes,
for fire fighting or street cleaning, to irrigate agriculture,
or recharge wetlands in times of drought. In 1980, in the absence
of national reuse regulations, EPA published the first edition
of Guidelines for Water Reuse. While sources of water for reclamation
may range from industrial process wastewaters to stormwater runoff,
the EPA guidelines focused on the effluent generated by domestic
wastewater treatment facilities. In 1992 a second edition was
published, doubled in size and updated with new information including
an inventory of state regulations and treatment guidelines. This
year the book is being updated again. Published and distributed
by EPA’s Technology Transfer program, the 2004 Guidelines
for Water Reuse include public health issues, state requirements
and problems of emerging pathogens and chemicals of concern. But
the basic objectives of the document remain the same: to make
water managers and resource planners aware of the proven practices
of water reclamation.
Americans draw about 350 billion gallons of fresh water every day
from surface sources (rivers, lakes) and ground sources (aquifers,
wells). About 80 percent goes to powering humans and their habitats–that
is, to irrigate crops and produce electricity–although most
water used for cooling power plants is quickly returned to the
environment. Water departments deliver to households and businesses
another big gulp of about 13 percent, while industry uses 5 percent
and mining about 1 percent. The basic idea behind water reclamation
is that many of these needs do not require potable water and should
not be draining precious reserves from aquifers.
As early as 1958, the United Nations Economic and Social Council
recommended that no higher-quality water should be used for any
purpose that could tolerate a lower grade water. Americans are
beginning to heed the UN’s advice and water reuse is now
a large and growing conservation practice. Some 1.7 billion gallons
of U.S. wastewater are reused every day, and reclamation continues
to grow at an estimated 15 percent per year. Twenty five states
have adopted regulations for water reuse and 16 others have guidelines
or design standards. Florida is the top user of reclaimed water
(about 585 million gallons per day), but California is close behind.
Since California has the nation’s largest population and
is the largest user of fresh water (about 11 percent of the U.S.
total), it’s not surprising that, by 2010, the state plans
to double its present water reclamation rate of 525 million gallons
of water per day. Other states with major reclamation systems
include Texas, Colorado, Nevada (annual rainfall: 4 inches, and
the first state to use reclaimed water in 1926), Georgia and Washington.
The new EPA Guidelines for Water Reuse offers many case studies
from states that use reclaimed water. Technical details will interest
water supply professionals; the following sidelights may interest
browsers.
- St. Petersburg, Florida, has had a water reclamation and reuse
program since 1976. Although the city has experienced a 10
percent population growth since that date, it has had no significant
increase in potable water demand, thus eliminating the need
for costly expansion of drinking water treatment facilities.
- Costs of implementing a water reclamation and reuse program
are determined by local governments and financed by a variety
of funding options that may include user revenues, state or
federal grants, developer contributions or publicly approved
general obligation bonds. Successful programs strive to become
financially self-sufficient as soon as possible by generating
adequate revenue through local sources.
- Reclaimed waters require separate piping systems (usually
painted purple to distinguish them from drinking water systems).
Installation of water reuse systems in new areas under construction
is less costly and potentially more flexible than in older
established neighborhoods. In Irvine, California, the early
adoption of water reclamation programs for irrigation is giving
the Irvine water district the flexibility to adapt to changing
needs as area farms give way to housing, high-rises and shopping
centers. While about 1,000 acres of fruits, vegetables and
nursery products are still irrigated with reclaimed water,
urban use has grown to include 80 per cent of all business
and community landscaping, among many other uses. The quality
of Irvine’s reclaimed water is so high it was awarded
California’s first ‘unrestricted use’ permit,
meaning the water may be used for all purposes except drinking.
- Once adopted, reclaimed water programs tend to expand to
new uses. In Orlando’s Walt Disney World Resort Complex,
a reclaimed water system was initially limited to five golf
courses and some landscape irrigation. Today, 10 years later,
reclaimed water is used for all nonpotable needs within the
resort complex, including wash-down of roadways and other
impervious surfaces, construction (concrete mixing and cleanup),
cooling tower water, fire-protection, and landscape irrigation.
- Reclaimed water can enhance urban esthetics and recreational
water activities. The water flow in San Antonio’s famous
downtown Riverwalk is sustained by high-quality reclaimed
water to preserve this attractive tourist destination and
reduce demand on Texas groundwater reserves. Tucson’s
14-acre Lakeside Lake began receiving up to 45,000 gallons
per day of reclaimed water in 1990 to enhance boating, fishing
and other recreational activities.
- After a wake-up call from the Metropolitan Water District
of Southern California that
the area’s water demand would exceed supplies by 326
billion gallons a year by 2010,
the region adopted a broad-based conservation program. Water
reclamation and reuse
is a key feature of the program. The district currently uses
about 62 billion gallons of reclaimed water annually for irrigation
and industrial purposes; it proposes to more-than triple that
amount to195 billion gallons a year by 2010. Combined with
conservation incentives, rebate programs, groundwater storage
and water exchange agreements, the conservation program expects
to meet district water needs for the next ten years, even
during times of drought.
The 2004 Guidelines for Water Reuse, compiled by a team of 75 authors
and 50 reviewers–all experts in their fields–offers
many case studies of successful reuse programs in the U.S. It
also devotes a chapter to reuse projects and issues in other countries
around the world. For more information, please visit http://www.epa.gov/ORD/NRMRL/pubs/625r04108/625r04108.htm.
Contact: Patricia Schultz, Office of Public Affairs, 513-569-7966,
or e-mail to: schultz.patricia@epa.gov.
New Risk Management
Research Publications
Gonsoulin, Mary E.. Jason R. Masoner, Mike
L. Cook and Thomas E. Short. 2003. “Water Quality Assessment
of Lake Texoma Beaches, 1999-2001.” Proceedings of the
Okla. Acad. Sci. 83:63-72. http://digital.library.okstate.edu/
Holub, Scott M. and Kate Lajtha. 2004 “The Fate and Retention
of Organic and Inorganic 15N-Nitrogen in an Old-Growth Forest
in Western Oregon.” Ecosystems, 7(4):368-380. http://www.springerlink.com
Risk Management Research
Meetings
"Pit Lakes 2004" is a conference
to exchange scientific information on the characterization, modeling
and remediation of pit lakes to be held in Reno, NV, November
16-18. Registration information is available at the conference
web site http://www.epa.gov/ttbnrmrl/pitlakes.htm.
Or contact Alina Martin, SAIC, at 703-318-4678.
Other Meetings 
The 15th Annual West Coast International Conference
on Soils, Sediments and Water of the Association for Environmental
Health and Sciences will be held in San Diego, CA, March 14-17,
2005. Abstracts are invited from EPA researchers, as well as EPA-funded
researchers from outside the agency, to be presented at a special
session on Developments in Bioremediation Strategies for Contaminated
Sediments, sponsored by Nationa Risk Management Research Laboratory’s
Land remediation and Pollution Control Division. For full information,
please go to http://www.epa.gov/ORD/NRMRL/announce/announce03172004.htm.
The Environmental & Water Resource Institute
(EWRI) of the American Society of Civil Engineers (ASCE) is holding
its annual World Water & Environmental Congress in Anchorage,
Alaska on May 15-19, 2005. The meeting will be organized around
the theme "Impacts of Climate Change," and will include
Continuing Education seminars and short courses with opportunities
to accumulate professional development hours. The flyer announcing
the 2005 World Water & Environment Congress is currently posted
on the ASCE web site: http://www.asce.org/conferences/ewri2005.
Environmental and water resource professionals are invited to
submit sessions or papers.
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