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What is "ecological engineering"?

The term, "ecological engineering," was first coined by Howard T. Odum in 1962. Howard Odum is now professor emeritus at the University of Florida, where his work in systems ecology has flourished.

Ecological engineering, he wrote, is "those cases where the energy supplied by man is small relative to the natural sources but sufficient to produce large effects in the resulting patterns and processes." (H.T. Odum, 1962, "Man and Ecosystem" Proceedings, Lockwood Conference on the Suburban Forest and Ecology. Bulletin Connecticut Agric. Station)

Another definition that follows from that relates to ecosystem management by human society (Center for Wetlands, University of Florida) :

"Ecological engineering is the design of sustainable ecosystems that integrate human society with its natural environment for the benefit of both. It involves the design, construction and management of ecosystems that have value to both humans and the environment. Ecological engineering combines basic and applied science from engineering, ecology, economics, and natural sciences for the restoration and construction of aquatic and terrestrial ecosystems. The field is increasing in breadth and depth as more opportunities to design and use ecosystems as interfaces between technology and environment are explored."

Another definition seeks to use the ecological paradigm to construct ecologies to solve vexing world-class problems, such as pollution:

It is predicated on the believe that the self-organizing order found in stable ecosystms is so universal that it can be applied as an engineering discipline to solve the pressing problems of global pollution, food production and efficient resource-utilization, while providing a high quality of life for all human society. (David Del Porto)

In this definition, the ecological paradigm reveals how to safely utilize the polluting components of unwanted residuals, or "wastes," to ultimately grow green plants that have value to human society, but not at the expense of aquatic and terrestrial ecosystems. Planning, design and construction with the ecological paradigm as a template is the work of ecological engineers.


 

The Agricultural Solution to Importing Petroleum, a paper by David Del Porto [click here for PDF]


 

Definitions

In 1995, Carol Steinfeld and David Del Porto wrote some definitions for Gale Publishing's Encyclopedia of the Environment. A Sustainable Strategies engineer posted them to the web page, simply to the boost the content. There they stayed, and over the years, many people have told us that they found these definitions valuable. So, to continue the tradition...

Phytoremediation, Sanitation, Sustainable Architecture, Permaculture

Phytoremediation

Phytoremediation combines the Greek word "phyton", (plant), with the Latin word "remediare", (to remedy) to describe a system whereby certain plants, working together with soil organisms, can transform contaminants into harmless and often, valuable forms. This practice is increasingly used to remediate sites contaminated with heavy metals and toxic organic compounds.

Planning, engineering and design with the ecological paradigm as our template is the work of Sustainable Strategies. For example, the ecological paradigm reveals how to safely utilize all of the polluting components and water of human and animal wastewater to ultimately grow plants that have economic value.

We use the term Wastewater Garden to describe our phytoremediation and evapo-transpiration approach to effluent management problems. The objective is to drain pretreated wastewater into an appropriately engineered gardens or forests of phreatophytes: plants known for fast growth and high water usage rates. These plants and their microbially-active rhizosphere will transform pollutants, including the nutrient nitrogen, into valuable biomass and use up the remaining water via evaporation and transpiration.

Phytoremediation takes advantage of plants' nutrient utilization processes to take in water and nutrients through roots, transpire water through leaves, and act as a transformation system to metabolize organic compounds, such as oil and pesticides. Or they may absorb and bioaccumulate toxic trace elements including the heavy metals, lead, cadmium, and selenium. In some cases, plants contain 1,000 times more metal than the soil in which they grow. Heavy metals are closely related to the elements plants use for growth. "In many cases, the plants cannot tell the difference" says Ilya Raskin, professor of plant sciences in the Center for Agricultural Molecular Biology at Rutgers University.

Phytoremediation is an affordable technology that is most useful when contaminants are within the root zone of the plants (top three to six feet). For sites with contamination spread over a large area, phytoremediation may be the only economically feasible technology. The process is relatively inexpensive because it uses the same equipment and supplies used in agriculture.

Soil microorganisms can degrade organic contaminants. This is called bioremediation and has been used for many years both as an in-situ process and in land farming operations with soil removed from sites.

Dr. Raskin also demonstrated the utility of certain varieties of mustard plants in removing such metals as chromium, lead, cadmium and zinc from contaminated soil and used hydroponic plant cultures to remove toxic metals from aqueous waste streams.

Plants can accelerate bioremediation in surface soils by their ability to stimulate soil microorganisms through the release of nutrients from and the transport of oxygen to their roots. The zone of soil closely associated with the plant root, the rhizosphere, has much higher numbers of metabolically active microorganisms than unplanted soil. The rhizosphere is a zone of increased microbial activity and biomass at the root-soil interface that is under the interface of the plant roots. It is this symbiotic relationship between soil microbes that is responsible for the accelerated degradation of soil contaminants.

The interaction between plants and microbial communities in the rhizosphere is complex and has evolved to the mutual benefit of both organisms. Plants sustain large microbial populations in the rhizosphere by secreting substances such as carbohydrates and amino acids through root cells and by sloughing root epidermal cells. Also, root cells secrete mucigel, a gelatinous substance that is a lubricant for root penetration through the soil during growth. Using this supply of nutrients, soil microorganisms proliferate to form the plant rhizosphere.

In addition to this rhizosphere effect, plants themselves are able to passively take up a wide range of organic wastes from soil through their roots. One of the more important roles of soil microorganisms is the decomposition of organic residues with the release of plant nutrient elements such as carbon, nitrogen, potassium, phosphate and sulfur. A significant amount of the CO2 in the atmosphere is utilized for organic matter synthesis primarily through photosynthesis. This transformation of carbon dioxide and the subsequent sequestering of the carbon as root biomass contributes to balancing the effect of burning fossil fuels on global warming and cooling.

Compounds are frequently transformed in the plant tissue into less toxic forms or sequestered and concentrated so they can be removed (harvested) with the plant. For example, mustard greens were used to remove 45% of the excess lead from a yard in Boston to ensure the safety of children who play there. The sequestered lead was carefully removed and safely disposed of. Besides mustard greens, pumpkin vines were used to clean up an old Magic Marker factory site in Trenton, New Jersey. Hydroponically grown sunflowers were used to absorb radioactive metals near the Chernobyl nuclear site in the Ukraine as well as a uranium plant in Ohio. The mustard's hyper-accumulation results in much less material for disposal. The composting of plant material can be another highly efficient stage in the breakdown of contaminants removed from the soil.

When large plants such as willows, poplars and bamboo are used, the idea is to move as much water through them as possible so that they take up as much of the contaminants as possible. In 1991 the Miami Conservancy District Aquifer Update, No. 1.1 reported that a single willow tree can, on a hot summer day, transpire over 19 cubic meters of water (5,000 gallons)!, One hectare of a herbaceous plant like saltwater cord grass evapotranspires up to 80 cubic meters (21,000 gallons) of water per day. Once the heavy metals are absorbed, they are sequestered in the plants' leaves and/or roots. Any organic compounds that are absorbed are metabolized.

Absorption of large amounts of nutrients by plants (and only a small amount of plant toxins that might be harmful to them,) is the key factor. Plants generally absorb large amounts of elements they need for growth and only small amounts of toxic elements that could harm them. Therefore, phytoremediation is a cost-effective alternative to conventional remediation methods. Cleaning the top 15 centimeters (six inches) of contaminated soil with phytoremediation costs an estimated $2,500 to $15,000 per hectare (2.5 acres), compared to $7,500 to $20,000 per hectare for on-site microbial remediation. If the soil is moved, the costs escalate, but phytoremediation costs are still far below those of traditional remediation methods, such as stripping the contaminants from the soil using physical, chemical or thermal processes according to Dr. Scott Cunningham, a scientist at Dupont Central Research for Environmental Biotechnology.

Plants are effective at remediating soils contaminated with organic chemical wastes, such as solvents, petrochemicals, wood preservatives, explosives and pesticides. The conventional technology for soil cleanup is to remove the soil and isolate it in a hazardous waste landfill or incinerate it.

"Phytoremediation", says Dr. Ray Hinchman, botanist and plant physiologist at Argonne National Laboratory, is "an in-situ approach," not reliant on the transport of contaminated material to other sites. Organic contaminants are, in many cases, completely destroyed (converted to CO2 and H2O) rather than simply immobilized or stored.

Salt-tolerant plants, called halophytes, have reduced the salt levels in soils by 65% in only two years in one project involving brine-damaged land from run-off from oil and gas production in Oklahoma. After the salt was reduced, the halophytes died and native grasses, which failed to thrive when too much salt entered the soil, naturally returned, replacing the salt-converting plants.

The establishment of vegetation on a site also reduces soil erosion by wind and water, which helps to prevent the spread of contaminants and reduces exposure of humans and animals.

Classes of organic compounds that are more rapidly degraded in rhizosphere soil than in unplanted soil include:

· Total petroleum hydrocarbons; polycyclic aromatic hydrocarbons
· Chlorinated pesticides (PCP, 2,4-D)
· Other chlorinated compounds (PCBs, TCE)
· Explosives (TNT, DNT)
· Organophosphate insecticides (diazanon and parathion)
· Surfactants (detergents)
· Nutrients (N,P,K) and organic compounds

Some plants used for phytoremediation are:

· Alfalfa (symbiotic with hydrocarbon-degrading bacteria)
· Arabidopsis (carries a bacterial gene that transforms mercury into a gaseous state)
· Bamboo family (accumulates silica in it's stalk and nitrogen as crude protein in it's leaves)
· Bladder campion (accumulates zinc and copper)
· Brassica juncea (Indian mustard greens) (accumulates selenium, sulfur, lead, chromium, cadmi um, nickel, zinc, and copper)
· Buxaceae (boxwood) and Euphorbiaceae (a succulent) (accumulates nickel)
· Compositae family (symbiotic with Arthrobacter bacteria, accumulates cesium and strontium)
· Ordinary tomato and alpine pennycress (accumulates lead, zinc and cadmium)
· Poplar (used in the absorption of the pesticide, atrazine)

 



Sustainable Architecture by Carol Steinfeld

Sustainable architecture refers to the practice of designing buildings which create living environments that work to minimize man's use of resources. This is reflected both in a building's construction materials and methods and in its use of resources, such as in heating, cooling, power, water, and wastewater treatment.

The operating concept is that structures so designed "sustain" their users by providing healthy built environments, improving the quality of life, and avoiding the production of waste, to preserve the long-term survivability of the human species.

Hunter and Amory Lovins of the Rocky Mountain Institute say the purpose of sustainable architecture is to "meet the needs of the present without compromising the ability of future generations to meet their own needs."

The term, however, is a broad one, and is used to describe a wide variety of aspects of building design and use.

For some, the term applies to designing buildings that produce as much energy as they consume. Another interpretation calls for a consciousness of the spiritual significance of a building's design, construction, and siting. Also, some maintain that integral to this approach is that buildings must foster the spiritual and physical well-being of their users.

One school of thought maintains that, in its highest form, sustainable architecture replicates a stable ecosystem. According to noted ecological engineer, David Del Porto, a building designed for sustainability is a balanced system where there are no wastes, because the outputs of one process become the inputs of another. Energy, matter, and information are cas-caded through connected processes in cyclical pathways, which by virtue of their efficiency and interdependence, yield the matrix elements of environmental and economic security, high quality of life, and no waste. The constant input of the sun replenishes any energy lost in the process.2

"Sustainability," as it relates to resources, became a widely used term with Lester Brown's book, Building a Sustainable Society, and with the publishing of the International Union on the Conservation of Nature's "World Conservation Strategy" in 1980.

Sustainability then came to describe a state whereby natural renewable resources are used in a manner that does not eliminate or degrade them or otherwise dimish their renewable usefulness for future generations, while maintaining effectively constant or non-declining stocks of natural resources such as soil, groundwater, and biomass. (World Resources Institute)

Before "sustainable architecture," the term "solar architecture" was used to express the architectural approach to reducing the consumption of natural resources and fuels by capturing solar energy. This evolved into the current and broader concept of sustainable architecture, which expands the scope of issues involved to include water use, climate control, food production, air purification, solid waste reclamation, wastewater treatment and overall energy efficiency. It also encompasses building materials, emphasizing the use of local materials, renewable resources and recycled materials, as well as the mental and physical comfort of the building's inhabitants. In addition, sustainable architecture calls for the siting and design of a building to harmonize with its surroundings.

The United Nations lists the following five principles of sustainable architecture:

1. Healthful Interior Environment. All possible measures are to be taken to ensure that materials and building systems do not emit toxic substances and gasses into the interior atmosphere. Additional measures are to be taken to clean and revitalize interior air with filtration and plantings.

2. Resource Efficiency. All possible measures are to be taken to ensure that the building's use of energy and other resources is minimal. Cooling, heating and lighting systems are to use methods and products that conserve or eliminate energy use. Water use and the production of wastewater are minimized.

3. Ecologically Benign Materials. All possible measures are to be taken to use building materials and products that minimize destruction of the global environment. Wood is to be selected based on non-destructive forestry practices. Other materials and products are to be considered based on the toxic waste output of production. Many practitioners cite an additional criterion: that the long-term environmental and societal costs to produce the building's materials must be considered and prove in keeping with sustainability goals.

4. Environmental Form. All possible measures are to be taken to relate the form and plan of the design to the site, the region and the climate. Measures are to be taken to "heal" and augment the ecology of the site. Accomodations are to be made for recycling and energy efficiency. Measures are to be taken to relate the form of building to a harmonious relationship between the inhabitants and nature.

5. Good Design. All possible measures are to be taken to achieve an efficient, long-lasting and elegant relationship of use areas, circulation, building form, mechanical systems and construction technology. Symbolic relationships with appropriate history, the Earth and spiritual principles are to be searched for and expressed. Finished buildings shall be well built, easy to use and beautiful.


Examples of sustainable architecture include:
· The NMB Bank headquarters in Amsterdam, The Netherlands. Constructed in 1978, this approximately 150,000 square-foot complex is a meandering S-curve of 10 buildings, each offering different orientations and views of gardens. Constructed of 'natural' and low-polluting materials, the buildings feature organic design lines, indoor and outdoor gardens, passive solar elements, heat recovery, water features, and natural lighting and ventilation. Built for an estimated 5% more than a conventional office building, the NMB building's operating costs are only 30% of those of a conventional building.
· The Solar Living Center in Hopland, California, employs both passive and photovoltaic solar elements, as well as ecological wastewater systems.
The rice straw bale and cement building is constructed around a solar calendar.

Sustainable Architecture as a Movement
Some maintain that sustainability, as it relates to architecture, refers to a process and an attitude or viewpoint. Sustainability is "a process of responsible consumption, wherein waste is minimized, and buildings interact in balanced ways with natural environments and cycles, balancing the desires and activities of humankind within the integrity and carrying capacity of nature, and achieving a stable, long-term relationship within the limits of their local and global environment." (Rocky Mountain Institute)

However, sustainable architecture does not necessarily mean a reduction in material comfort. Sustainability represents a transition from a period of degradation of the natural environment (as represented by the industrial revolution and its associated unplanned and wasteful patterns of growth) to a more humane and natural environment. It is doing more with less.

Proponents of sustainable architecture occasionally debate the broader applications of the term. Some say that sustainable buildings should generate more energy over time (in the form of power, etc.) than was required to construct, fabricate their materials, operate and maintain them. This is also referred to as "regenerative architecture," which John Tillman Lyle sums up in his book, Regenerative Design for Sustainable Development., as "living on the interest yielded by natural resources rather than the capital." Others simply see it as an approach to making buildings less consumptive of natural resources.

Spiritual Aspects of Sustainable Architecture
A spiritual viewpoint is that sustainable architecture is "stewardship," a recognition and celebration of the human environment as a vital part of the larger universe and of humankind's role as caretakers of the earth. Viewed in this way, resources are regarded as sacred. Another perspective is that the creation of a building in the likeness of a living system as akin to religious, as a divine entity creates a living order.

Although the term communicates slightly different meanings to various audiences, it nevertheless serves as a consciousness-raising focus for creating greater concern for the built environment and its long-term viability. Rather than representing a return to subsistence living, buildings designed for sustainability aim to improve the quality and standards of living. Sustainable architecture recognizes people as temporary stewards of their environments, working toward a respect for natural systems and a higher quality of life.

Sources:

Orr, David W., Ecological Literacy, State University of New York Press, 1992.

World Resources 1992-93: A Guide to the Global Environment. New York: Oxford University Press, 1992.

World Resources Institute, "Dimensions of Sustainable Development," a report. Washington, DC: WRI, 1990.

Nebel, B.J., Environmental Science: The Way the World Works, third edition. New York: Prentice Hall, 1990.

D. Barnett and W. Browning, "A Primer on Sustainable Building," a report. Colorado: Rocky Mountain Institute, 1995.

Tillman Lyle, John, Regenerative Design for Sustainable Development. New York: John Wiley & Sons, Inc., 1994.

Kremers, Jack, "Sustainable Architecture," Architronic, World Wide Web page: http://www.saed.kent.edu/Architronic/v4n3.03.homepage.html, December 1996.


Permaculture by Carol Steinfeld

Permaculture is an approach to land management that creates high-yielding, low-energy, self-perpetuating systems whereby the functions of animals, plants, humans and the Earth are integrated to maximize their value and create sustainable human habitats.

Permaculture brings together disciplines relating to food, shelter, energy, water, waste management, economics, and social sciences. It aims to maximize a site's productivity, while maintaining ecosystems and restoring damaged land to a healthy, life-promoting state.

The term was first coined by Bill Mollison of Tasmania, Australia in 1972, by merging the terms, "permanent" and "agriculture." Although originally developed for small subsistence farms, the practice has expanded to apply to gardens and urban settings. Some consider it a lifestyle as much as a design approach.

Permaculture principles focus on designs for small-scale intensive systems that are labor-efficient and use biological resources instead of fossil fuels. These designs stress ecological connections and closed energy and material loops. The core of permaculture is integrating working relationships and connections between all things. Each component in a system performs multiple functions, and each function is supported by many elements.

Key to efficient permaculture design is observing and replicating natural ecosystems, whereby designers maximize diversity with polycultures, stress efficient energy planning for houses and settlements, and use and accelerate natural plant succession.

The philosophy behind permaculture is one of working with, rather than against nature, of looking at systems in all of their functions, and using them for multiple purposes. It is a system of agriculture that aims to endure without constant human inputs and does not deplete the land.

According to Mollison, its basic characteristics are:
1. It makes the most of small landscapes, using intensive practices. Ideally, nothing is wasted, and everything is arranged so the least amount of effort is exerted and the highest yield from the systems is gained.
2. Systems are designed that use and complement the natural systems that are present, e.g. storm water is controlled with planted swales, not concrete drains. The design harvests the natural flows of energy through the landscape (sunlight, rain, plant and animal behaviors, etc.).
3. Promoting diversity in plant species, varieties, yield, microclimate and habitat. It maintains that, in a monoculture, a single species cannot make full use of all of the available energy and nutrients. Wild or little-selected animal and plant species are used.
4. Each element performs many functions in the system, e.g., a fruit tree provides not only a crop, but wind shelter, a trellis, soil conditioning, shade and roosting for birds.
5. The long-term evolution of the land is recognized, and those changes are incorporated in planning.
6. Agriculture, animal husbandry, extant forest management and animal cropping, as well as landform engineering are integrated.
7. Difficult landscapes (rocky, marshy, marginal, steep) not typically suited to other systems are utilized.
8. It involves long-term and evolving land-use planning, using diverse flora and fauna in various ways at different times, recognizing that different species use different nutrients and resources.

Permaculture systems typically feature:
· passive energy systems and minimal external energy needs
· climate control on site
· planned future developments
· provision for food self-sufficiency on site
· wastes safely disposed of on site
· low-maintenance structures and grounds
· water supply assured and conserved
· fire, cold, excess heat and wind factors controlled and directed

Permaculture started as a strategy for designing systems for "permanent" or perennial agriculture, by creating agroforestry systems using tree crops, shrubs, vines and herbaceous plants in highly productive symbiotic assemblages. The practice was originally oriented to subsistence farms in Tasmania, which typically were small and on poor land. It was then extended to include other landscapes, urban settings and climates worldwide, and has even been applied to other systems, such as houses and factories.

Permaculture as a Life Philosophy
Some consider permaculture a life philosophy. In this context, permaculture emphasizes putting oneself in a symbiotic relationship with the earth and one's community. Permaculture is oriented to place, with reliance on native plants and a close awareness of the ecosystem. It revolves around self-reliance, growing food and building attractive energy-efficient structures from local materials.

Designing a permaculture landscape begins with assessing a site's native features (from soil structure, microclimates, cycles of decay, existing flora and fauna) in order to take advantage of existing resources and to select and adapt technologies (methods of composting, gardening, irrigation, generating electricity) to the site.

Multi-functional living systems abound in a typical permaculture design. The following are examples of some specific permaculture practices and approaches:

Animals
Animals are raised for their value as producers of food, skins and manure, and as pollinators, heat sources, gas producers, earth tillers and pest control. For example, rabbits raised in a rabbit hutch are fed kitchen scraps; their droppings fall to worm bins (vermiculture) as fodder for worms. The resulting worm castings are used to fertilize gardens. In the winter, the rabbits are harvested for their meat and fur. Also, a movable chicken hutch can be used to place chickens in gardens where they effectively till and fertilize the soil.

Plants
Particular varieties of trees are chosen for their fuel, forage, material (for fences, structures and shelters), heat reflector and windbreak values, as well as crop diversification. When they are young, the trees may act as hedgerow, then grow to serve as a fuel source. Plants act as trellises for other plants, screen and shade other plants, provide nutrients to plants, cross-fertilize plants (such as varieties of plums and nuts), help repel pests, prevent erosion and provide spare parts (grafts) for plants. Fruit trees and vines are planted strategically around a house to provide shade. In a home's front yard, attractive gardens feature high-yielding food, medicinal and culinary plants where they are easily accessed. Some crops are planted for their self-propagating patterns, such as leeks, onions, potatoes and garlic.

Water
Water harvesting is an essential function in a permaculture landscape, and is supported by as many components as possible. Filtration of water for animals may be provided with shells and water plants. Water pathways are traced, and systems are created for collecting it. Swales may direct rain water and run-off to fruit trees. Run-off water from culverts may be directed to ponds where water plants and fish are raised, and where it can be used for irrigation and firefighting. Water can be collected from roofs. Composting toilets and septic systems with planted leaching beds may be employed.

Soil Health
Insects and crops are used to aerate the soil. Mulching, green crops, composting and strategic planting are employed to build soil health. Permaculture grows forests and schrubs to protect the soil, and uses plows that do not turn the soil. Food crops, such as corn and legumes, are chosen for their low-maintenance qualities and their ability to fix nitrogen in the soil.

Shelter
Permaculture emphasizes reactive homes, sheltered from cold winds with windbreak planting; oriented on an east-west axis facing the sun, usually with a greenhouse; and well sealed. They should use few resources not found on site. Shelters can be built into the earth, with living turf roofs. Also, living trees and plants are sometimes used to create shelters.

Mollison has written five books on the topic, including Introduction to Permaculture, Permaculture A Designer's Manual, Permaculture One, Permaculture Two and Permaculture: A Practical Guide for a Sustainable Future. Several permaculture organizations and model projects exist around the world.

Permaculture offers an environmental design practice for making better use of resources in a variety of growing settings. What started as a method for cultivating desert land has grown into a system that integrates living systems, fostering greater consciousness of ecosystems and helping to ensure economic and ecological sustainability for its practitioners.

For more information about permaculture, contact:

Permaculture Resources, 56 Farmersville Road, Califon, NJ 07830. 800-832-6285

The Permaculture Activist, P.O. Box 1209, Black Mountain, NC 28711

Cross Timbers Permaculture Institute conducts workshops on permaculture designs, from small animal systems to strawbale house construction. Route 1, Box 210-A, Glen Rose, TX 76043. (817) 897-9402

Gap Mountain Permaculture Institute offers programs. 50 Bullard Road, Jaffrey, NH 03542. (603) 532-7321

Sources:

Barnes, Lee, "The Permaculture Connections," Southeastern Permaculture Network News

Mollison, Bill, Permaculture: A Designer's Manual, Permaculture One, and Permaculture Two, Australia: Tagari, 1979.

By Carol Steinfeld



Sanitation by David Del Porto

Sanitation can be defined the measures, methods and activities that prevent the transmission of diseases and ensure public health.

Specifically, "sanitation" refers to the hygienic principles and practices relating to the safe collection, removal and disposal of human excreta, refuse and waste water.

For a household, sanitation refers to the provision and ongoing operation and maintenance of a safe and easily accessible means of disposing of human excreta, garbage and waste water, and providing an effective barrier against excreta-related diseases.

The problems that result from inadequate sanitation can be illustrated by the following events in history:

1700 BC: Ahead of his time by a few thousand years, King Minos of Crete had running water in his bathrooms in his palace at Knossos. Although there is evidence of plumbing and sewerage systems at several ancient sites, including the cloaca maxima (or great sewer) of ancient Rome, their use did not become widespread until modern times.

1817: A major epidemic of cholera hit Calcutta, India, after a national festival. There is no record of exactly how many people were affected, but there were 10,000 fatalities among British troops there alone. The epidemic then spread to other countries and to the United States and Canada in 1832. The governor of New York quarantined the Canadian border in a vain attempt to stop the epidemic. When cholera reached New York City, people were so frightened, they either fled or stayed inside, leaving the city streets deserted.

1854: A London physician, Dr. John Snow, demonstrated that cholera deaths in an area of the city could all be traced to a common public drinking water pump that was contaminated with sewage from a nearby house. Although he could not identify the exact cause, he did convince authorities to close the pump.

1859: The British Parliament was suspended during the summer because of the stench coming from the Thames. As was the case in many cities at this time, storm sewers carried a combination of sewage, street debris and other wastes, and storm water to the nearest body of water. According to one account, the river began to "seethe and ferment under a burning sun."

1892: The comma-shaped bacteria that causes cholera was identified by German scientist, Robert Loch, during an epidemic in Hamburg. His discovery proved the relationship between contaminated water and the disease.

1939: Sixty people died in an outbreak of typhoid fever at Manteno State Hospital in Illinois. The cause was traced to a sewer line passing too close to the hospital's water supply.

1940: A valve [that was] accidentally opened caused polluted water from the Genessee River to be pumped into the Rochester, New York, public water supply system. About 35,000 cases of gastroenteritis and six cases of typhoid fever were reported.

1955: Water containing a large amount of sewage was blamed for overwhelming a water treatment plant and causing an epidemic of hepatitis in Delhi, India. An estimated one million people were infected.

1961: A worldwide epidemic of cholera began in Indonesia and spread to eastern Asia and India by

1964; Russia, Iran, and Iraq by 1966; Africa by 1970; and Latin America by 1991.

1968: A four-year epidemic of dysentery began in Central America resulting in more than 500,000 cases and at least 20,000 deaths. Epidemic dysentery is currently a problem in many African nations.

1993: An outbreak of cryptosporidiosis in Milwaukee, Wisconsin, claimed 104 lives and infected more than 400,000 people, making it the largest recorded outbreak of waterborne disease in the United States.

The problem of sanitation in developed countries who have the luxury of adequate financial and technical resources is more with the consequences arising from inadequate commercial food preparation and the results of bacteria becoming resistant to disinfection techniques and antibiotics. Flush toilets and high quality drinking water supplies have all but eliminated cholera and epidemic diaherrheal diseases.

However, in many developing countries, such as the Pacific islands, inadequate sanitation is still the cause of life or death struggles.

In 1992, the South Pacific Regional Environment Programme (SPREP) and a Land-Based Pollutants Inventory stated that "[t]he disposal of solid and liquid wastes (particularly of human excrement and household garbage in urban areas), which have long plagued the Pacific, emerge now as perhaps the foremost regional environmental problem of the decade."

High levels of fecal coliform bacteria have been found in surface and coastal waters. The SPREP Land-Based Sources of Marine Pollution Inventory describes the Federated States of Micronesia's sewage pollution problems in striking terms: The prevalence of water-related diseases and water quality monitoring data indicate that the sewage pollutant loading to the environment is very high. A recent waste quality monitoring study (as part of a workshop) was unable to find a clean, uncontaminated site in the Kolonia, Pohnpei area.

Many central wastewater treatment plants constructed with funds from United States Environmental Protection Agency in Pohnpei and in Chuuk States have failed due to lack of trained personnel and funding for maintenance.

In addition, septic systems used in some rural areas are said to be of poor design and construction, while pour-flush toilets and latrines-which frequently overflow in heavy rains-are more common. Over-the-water latrines are found in many coastal areas, as well.

Eutrophication
In the Marshall Islands, signs of eutrophication-excess water plant growth due to too much nutrients-resulting from sewage disposal are evident next to settlements, particularly urban centers. According to a draft by the Marshall Islands NEMS, "one-gallon blooms occur along the coastline in Majuro and Ebeye, and are especially apparent on the lagoon side adjacent to households lacking toilet facilities." Stagnation of lagoon waters, reef degradation, and fish kills resulting from the low levels of oxygen have been well documented over the years. Additionally, red tides plague the lagoon waters adjacent to Majuro.

Groundwater Pollution
There is significant groundwater pollution in the Marshall Islands as well. The Marshall Island EPA estimates that more than 75 percent of the rural wells tested are contaminated with fecal coliform and other bacteria. Cholera, typhoid and various diarrheal disorders occur.

How Conventional Systems Fail
With very little industry present, most of these problems are blamed on domestic sewage, with the greatest contamination problems believed to be from pit latrines, septic tanks, and the complete lack of sanitation facilities for 60 percent of rural households. As is often the case, poor design and inappropriate placement of these systems are often identified as the cause of contamination problems. In fact, even the best of these systems in the most favorable soil conditions allow significant amounts of nutrients and pathogens into the surrounding environment, and the soil characteristics and high water table typically found on atolls significantly inhibits treatment. In addition, the lack of proper maintenance, due a lack of equipment to pump out septic tanks, is likely to have degraded the performance of these systems even further.

Forty percent of the population in the Republic of Palau is served by a secondary sewage treatment plant in the state of Koror, which is generally thought to provide adequate treatment. However the Koror State government has recently expressed concern over the possible contamination of Malakal Harbor, into which the plant discharges. Also, some low-lying areas served by the system experience periodic back-flows of sewage which run into mangrove areas, due to mechanical failures with pumps and electrical power outages. In other low-lying areas not covered by the sewer system, septic tanks and latrines are used, which also overflow, affecting marine water quality.

Rural areas primarily rely on latrines, causing localized marine contamination in some areas. Though there have been an increasing number of septic systems installed as part of a rural sanitation program funded by the United States, there is anecdotal evidence that they may not be very effective. Many of the septic tank leach fields may not be of adequate size. In addition, a number of the systems are not used at all, as some families prefer instead to use latrines since the actual toilets and enclosures are not provided with the septic tanks as part of the program.

Pollution from Livestock Operations
Wastewater problems also result from agriculture. According to the EPA, pig waste is considered to be a more significant problem than human sewage in many areas."

Sanitation Requirements in Developed Countries
Because sanitation has become a social responsibility, national, state and local governments have adopted regulations that, when followed, should provide adequate sanitation for the governed society. However, the very technologies and practices that were instituted to provide better health and sanitation now have been found to be contaminating ground and surface waters. For example, placing chlorine in drinking water and waste water to provide disinfection, has now been found to produce carcinogenic compounds called trihalomethanes and dioxin. Collecting sanitary waste and transporting them along with industrial waste is central sewers to inadequate treatment plants costing billions of dollars has failed to provide adequate protection for public health and environmental security.

A New Paradigm for Sanitation
Increasingly, the solution seems to be found in methods and practices that borrow from the stable ecosystems model of waste management. That is, there are no wastes, only resources that need to be connected to the appropriate organism that requires the residuals from one organism as the nutritional requirement of another. New waterless composting toilets that destroy human fecal organisms while they produce fertilizer, are now the technology of choice in the developing world and have found a growing niche in the developed world, as well. Wash water, rather than being disposed of into ground and surface waters, is now being utilized for irrigation. The combination of these two ecologically engineered technologies provides economical sanitation, eliminates pollution, and creates valuable fertilizers and plants, while reducing the use of potable water for irrigation and toilets.

Back to the Basics
Simple hand washing is now re-emerging as the most important measure in preventing disease transmission. Handwashing breaks the primary connection between surfaces contaminated with fecal organisms and the introduction of these pathogens into the human body. The use of basic soap and water, not exotic disinfectants, when practiced before eating and after defecating may save more lives than all of the modern methodologies and technologies combined.


Sources:

Pipeline, Summer 1996; Vol. 7, No. 3; Plumbing and Mechanical Engineer.

Salvato, J., Environmental Engineering and Sanitation, 4th ed.

Fair, Geyer, and Okun, Water and Wastewater Engineering, vol. 1.

"Sanitation Problems in Micronesia," a report. Concord, Mass.: Sustainable Strategies, 1997.





 

 

 

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