Management for the Islands:
Creating Gardens, Not Polluted Water
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Fiji Ecotourism Association conference
2000 ¥ Nadi, Fiji
for Ecological Pollution Prevention (CEPP)
P.O. Box 1330, Concord, MA 01742
Email: email@example.com Web: www.cepp.cc
Ecological Engineering & Design
50 Beharrell Street, Concord, MA 01742 USA
to slide presentation]
What's at Stake:
Chuuk Polluted Beach
On a beach at a hotel on Chuuk (Micronesia), a sign
warns visitors not to enter the water due to pollution. The pollution is from
the hotel's sewage.
This situation is a reminder of what's
at stake when waste is not well managed: not only is human and environmental health
compromised, but tourist attractions can also be spoiled.
answer is to use systems that divert potential pollutants from the environment.
The easiest way to do that is to use them up.
are some examples of ecological systems, with an emphasis on strategic utilization
and the simpler on-site aerobic systems (because our organizations have a history
with these systems in the Western and South Pacific islands).
Resort, Beqa Island, Fiji
On Beqa island, Lalati is an upmarket resort
($250 per person per night) with seven bures (guest houses) mostly attracting
divers and surfers. Its American owners wanted a wastewater system that would
not pollute the nearby coastline with septage. At the same time, septic pumpout
was not an option, due to their island location. Importing manufactured systems
from Canada, Europe, the United States and Australia was going to be expensive.
They had seen a community composting toilet that Sustainable
Strategies had built with the Fiji School of Medicine outside of Suva. Based on
this, they asked the firm to design a system for an upscale resort with low-cost,
locally available materials and with flush toilets--one that could be maintained
by the resort staff.
The result was this system:
- Each bure features a rooftop rainwater collection system, which drains to
a 2400-liter cistern that supplies most of the bure's water.
bure features a microflush toilet (1 pint/1/2-liter per flush) flushed with rainwater
and draining to an aerobic reactor (composting reactor), which was made on site
with materials available in Fiji. Leachate (liquid) drains to a lined aerobic
planter bed called a Wastewater Garden. All washwater (graywater) from the sinks
and showers also drains to the Wastewater Garden, which is planted with local
flowering thirsty plants. The aerobic reactors are changed out every few months,
and their contents, after further processing, is used safely on the landscape.
The kitchen is served by a similar system.
The staff of Lalati adds
coconut coir every few days. When a composting reactor fills (with this small
size, this takes anywhere from 3 months to 1 year), it is taken to a covered central
area to further process. In six months, the material should be fully processed
and ready to be added to a composting pile to further process or to be applied
to soil. (Although this resulting humus should be pathogen free, we do not advocate
its use on edible crops.)
Lalati's owners like the fact that the system
does not pollute the coastline (and the very sites that attract clients) and that
it is maintained by the resort staff. They also enjoyed significant cost savings
over a septic system.
Guests, they say, appreciate knowing that their accommodations
employ such an ecologically responsible system.
This system illustrates
the good economics of the ecological approach.
The Ecological Approach
It is less costly to prevent pollution than to treat it later.
- Prevents bacterial and chemical pollution (health risks)
nutrient pollution (unwanted water weeds, dying aquatic life and groundwater contamination)
- Conserves water (less water used, less water needs to be cleaned)
and reuses nutrients and water (saves money, no discharge)
- Can save money
over the cost of conventional systems
- The results: cost savings, natural
resources preserved, disease transmission avoided, nutrient and water cycle preserved
How: Conserve, Pretreat, Divert/Separate, Reuse/Reclaim
* Conserve Use water-efficient appliances and fixtures, so that less
wastewater is created. Examples: dry or microflush or vacuum-flush toilets and
low-flow faucets and showerheads.
* Pretreat Filter at the source to remove
larger particles so it can be used by plants. In kitchens, use grease and food
interceptors. Disinfect with ozone or UV if to be used for potable water.
Divert/Separate wastewater components By keeping flows separate, they can be better
and more cost-effectively treated and utilized.
* Reuse or reclaim
1. Plants use it up: Use the water and nutrients from wastewater to grow valuable
plants--either for decoration or for fiber value. Choose plants that are especially
hungry and thirsty to use up wastewater.
2. Reclaim it for other use: Flushing
toilets and urinals, washing, etc.
El Santuario, Baja California
El Santuario is a lower-impact guest facility in south-central
Baja California Sur, Mexico. Water is trucked in to the site from a mountain well.
Its owners needed a water-conserving system that would be acceptable to
their guests. CEPP, using designs from Sustainable Strategies, designed small
aerobic blackwater biofilter (enhanced composting toilets) with attractive blue
urine-diverting toilets made in Mexico. A larger system was built for an adjacent
area used for camping by kayak groups.
A Wastewater Garden was built for
the kitchen, and a system that combines urine from the urine-diverting toilets
and washwater from showers and sinks drains to a lined planter bed, which grows
hibiscus and other tropical plants that serve as a privacy barrier. The initial
construction took place as part of a three-day ecological wastewater workshop
attended by builders and Harvard School of Public Health graduate students.
Islands, Palau (Micronesia)
The Rock Islands are several small islands
off of the coast of Palau that are popular stopping spots for divers and groups
of snorkelers. High fecal coliform rates were measured around the islands, and
ultimately traced to the latrines. It was feared that this pollution could kill
off the sea life close to shore through eutrophication (and make visitors ill!).
Sponsored by the Palau government and the United States Environmental Protection
Agency, Sustainable Strategies was called in to design a zero-discharge system
that could be maintained by park personnel.
Sustainable Strategies designed
larger systems, using Carousel enhanced composting toilets based on a Norwegian
design that has proven most successful in studies in Scandinavia and the United
States. Each unit contains four chambers that are used interchangeably as they
fill up. This batch approach speeds the biological decomposition process and allows
for full biological decomposition, so that what is removed is a fully processed
and stable end-product called humus.
Extra liquid from the process is
drained to Wastewater Gardens located between the two toilet rooms.
system is now being considered for installation in homes in Palau.
Greenpeace Toilet, Yap (& Kosrae and Pohnpei, Micronesia)
In the early 1990s, Greenpeace contracted
Sustainable Strategies to design and conduct (with the Center for Clean Development)
an ecological zero-waste-discharge toilet system to help address sewage pollution
in the Pacific islands. Three systems were designed and demonstrated through local
construction workshops on the islands of Yap, Kosrae, Pohnpei, and Palau.
This system, now often called "the Greenpeace Toilet" (although its design has
been simplified; this newer version is called the "CEPP Twin-Bin with Net Composting
Toilet System"), was constructed with YapCAP on an outer island for use by a household.
In this system, one side is used at a time. When one chamber fills up, it is capped
and the other side is made active. When this one has filled, the other side can
be emptied. At this point, what is removed is a stable soil-like humus, which
can be used as a soil conditioner. It is usually five years before the first chamber
Improving on past designs, Sustainable Strategies optimized
the aeration features and engineered air-intakes and exhaust chimney sizes that
promote air and vapor throughput without power.
A follow-up visit to the
three islands in 1997 found that the site-built system had been most successfully
adopted in Pohnpei, where the local utility was involved in its promotion. On
Pohnpei, several systems had been independently built, including one for visitors
to Nan Madol, an ancient stone city.
Fiji and Samoa Community Systems
In 1996, the Fiji School of Medicine, through a grant from
the South Pacific Commission (SPC), conducted a composting toilet construction
workshop for students studying to be health agents. This system was built for
a community outside of Suva, using the Greenpeace Toilet design.
in December 2000, we found that it was not used regularly as it was deemed too
special for regular use. This is unfortunate, as it was constructed for high-volume
capacity. This is a common problem with systems that are "given" to communities
without demand by the community and more involvement. This underlines the need
for community-based introduction and management programs.
In 1999, CEPP
sold the plans for this system to Habitat for Humanity Fiji. It was built by an
American mission group, which left off several features due to time limitations.
As a result, the system produced odors. It was ultimately closed by the Fiji health
department because necessary approvals for construction had not been secured.
Our experiences suggest that ecological sanitation systems are best modeled
by willing owner-operators--but not built as service projects at the homes or
community sites of ambivalent users. Ultimately, the implementation program is
as important as good design.
These two experiences, as well as similar
ones in Western Samoa, have prompted the Center for Ecological Pollution Prevention
(CEPP) to cease selling the plans, only making them available to community-based
organizations through the Pacific EcoSan Center.
Rota-Loos, a take-off on the Norwegian Carousel design, have been introduced to
Western Samoa, with mixed results. Their performance issues here point to the
need to consider the composting reactor as a component of a system, not an all-function
This photo shows a Carousel aerobic
system in the kitchen pantry of a home in Virginia, USA. It is located there to
serve the toilet on the second floor. It is used to supplement the home's small
Maintenance involves adding some chunky carbon every week.
This owner uses a cup of bark every day.
These systems are increasingly
installed in upscale homes in the United States and other industrialized countries.
Ecological Zero-Waste-Discharge Systems in the U.S.A.
home was due to be condemned in 1998, because the local health agent feared that
septage from the home's cesspool would into leach the town's water supply, a clear
threat to public health.
Sustainable Strategies designed a system much
like the one for Lalati: integrated aerobic biofilters, source filtration and
Wastewater Garden aerobic planting bed. In this system, the Wastewater Garden
enclosed in a greenhouse (for warmth and to keep out precipitation--the warmer
the system, the faster the biological transformation process).
Strategies has designed a wide variety of such zero-waste-discharge systems for
homes, schools and other buildings in the United States.
Next slide: Old
Manse historic home in Concord, Mass.
One key to this approach is
to filter and pretreat at the source. By keeping effluents separate--not combining
them--they are more easily used. Besides the aerobic blackwater biofilter, other
source filters include grease interceptors and 30-micron filters.
This is a urine-diverting toilet in Sweden. It takes source
separation to a new level. Urine contains most of the nitrogen in wastewater--and
it is usually sterile in a healthy population. Keeping it out of the wastewater
mix allows the aerobic biofilter to perform better (by staying more aerobic).
These systems are also manufactured in Mexico.
Wastewater and Washwater
These aerobic planted (root zone) systems are increasingly installed
as it become clearer that leachfield are best designed shallow, so they can 1)
be within the root zones of plants and 2) be somewhat aerobic (faster processing).
They can be indoor features (slide: Audubon Center indoor planter bed).
They can be enclosed in moveable structures (slide: plastic dome greenhouse/glasshouse),
and they can be used to irrigate gardens (slide: CEPP office garden with tomatoes
and runner beans), although many health authorities may forbid use on edible crops.
Washwater/Wastewater Gardens are like wetlands but drier, allowing for
more aerobic activity, the faster processing. Pores in these systems provide homes
for beneficial bacteria, which destroy pathogens and convert nutrients to a plant
At the same time, the plants evapotranspire away the water.
These ecological systems can be scaled up to serve clusters of homes and even
Central Community Systems in U.S.A.
a Living Machines or Solar Aquatics system which serves a community of 300 homes.
It acts as a super-optimized artificial wetland.
Water is reclaimed for
flushing toilets or it can be disinfected and used for washing.
Hyacinth Large Central System, U.S.A.
This water hyacinth system is a
polishing pond that is part of a large wastewater treatment plant in San Diego,
California. This pond uses plants to take up the nutrients and further process
the effluent (tertiary treatment) before it is discharged to the ocean.
Beach Hotel Sign Again (No Swimming in the Sewage!)
The tropics are an
ideal environment for ecological systems, with their warm temperatures and availability
of hardy plants. Given the detrimental effects of sewage pollution in the Pacific
islands, further opportunities for using a variety of systems to use up wastewater
and prevent degradation of water supplies and aquatic resources deserve investigation.
They are certainly the most economic way to deal with these effluents.