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History of Sewers 101


Dear friends,

I never dreamed I would be posting something about toilets. Toilets are so much in the background of our lives -- private, taken for granted, dirty -- that I never thought of them as an appropriate topic for open discussion. And what is there useful to say about toilets, anyway?

Well, as with so many other things, Y2K has opened my eyes to a wild world behind the scenes. It turns out the world of human excrement is one of the most distorted, crazy, destructive realms in our lives. And one that tests our sincerity about wanting to build a better society.

Below I have three articles that I guarantee will transform your views on this subject. Really.

1) Judy Laddon's story of her Y2K Practice Day Epiphany
2) How Ole Ersson uses compost (including "humanure") to heat the water in his house, and
3) Rachel's mind boggling history of our sewage system

Problems with sewage is one of the most serious threats presented by Y2K, and one of the trickiest to handle -- and even to talk about. The fact that the sewage shouldn't even be there in the first place...well, it just staggers the mind. Do set aside ten or fifteen minutes to read this stuff.


Practicing Up for Breakdowns
One woman's reflections on the toilet and other humble essentials
By Judy Laddon

Recently I stepped out of my business-as-usual. I called it "Unplug for a Day." People are saying the Year 2000 computer problem could foul up a lot of stuff we usually depend on, all at once. I don't know what to expect, but two winters ago we had an ice storm and the power in our house went out for six days. Inside air temperatures plunged to 40 degrees. I wished I'd been better prepared. So I thought I'd give this Y2K Practice Day a try. Turn off the heat, lights, water and phones. Just for 24 hours. No big deal. My biggest worry was that I'd be bored.

I was really wrong about that.

I thought about the exercise for a month in advance, and I made some provisions: a couple buckets for water, fuel for the camp stove, food I could fix from the cooler since I would pretend the refrigerator didn't work. My husband Larry was game, though he let me do all the planning. I figured it would be kind of like camping at home. What I didn't count on was the soul-searching that resulted.

It was sparked by the thought of water. I filled two two-gallon containers with filtered drinking water, plenty for two people and three dogs, with enough left over for cooking. A 5-gallon soup pot was also filled with water, for washing or whatever else I wanted to do with it. But then there was the issue of the toilet. I wasn't going to cheat and leave the water on. And we hadn't yet set up a camp toilet. So I figured I'd just fill the bathtub with water and slog a bucket back and forth to the toilet tank for flushing.

This plan was not satisfying. The more I thought about it, the more frustrated I felt. In a real emergency, if water were limited, did it make sense to put this much clean drinking water down the toilet? Sure, I could do it for one day. But I wanted to experiment with low-water bathing, using two buckets of hot water, one soapy, one for rinsing. I couldn't do that if the tub was full of cold water.

So I took action. The day before Practice Day I complained to Larry, telling him I was bitterly disappointed not to try out an emergency toilet. This complaining really paid off. Larry, who's also a writer researching Year 2000 emergency preparedness, phoned a man named Joe Jenkins, author of a book called "The Humanure Handbook." Joe reassured my husband of the safe, sanitary and uncomplicated method for composting human waste. His solution is based on 20 years' of scholarly study. It turns out that the thermophilic bacteria in human waste, when mixed with organic material like peat moss or sawdust, creates temperatures over 120 degrees, rapidly killing pathogens just as Mother Nature intended.

We grew bold and daring and decided to use our emergency 5-gallon bucket with the toilet seat, layering everything with peat moss. Larry spent maybe a half hour building a new compost bin in the backyard. This was right up his alley, since he already composts all the kitchen scraps, yard and dog wastes.

Surprisingly, I found myself liking that little toilet. It was comfortable, clean, with no odor, just a slight earthy smell of peat moss. The soul-searching came when I contemplated going back to the flush toilet.

By coincidence I recently heard a presentation by the director of the local waste treatment facility. He was asked to address the issue of Year 2000 disruptions and explain what preparations were being made. In a matter-of-fact voice he described what a visitor from another planet would undoubtedly consider a barbaric custom. First, we defecate and urinate in our clean drinking water. In our town we have 800 miles of sewers that pipe this effluent to a treatment facility where they remove what are euphemistically called solids. Then they do a bunch more stuff to the water, I forget exactly what. But I do remember at one point they dose it with a potent poison--chlorine, of course--and then they do their best to remove the chlorine. When all this is done, the liquid gushes into the Spokane River.

At this meeting was a man named Keith who lives on the shores of Long Lake downriver from us. Keith was quite interested to know what might occur if our sewage treatment process were interrupted. The waste treatment official assured him that all would be well, but I couldn't help reflecting that Keith might end up drinking what we had been flushing. I like Keith. So I decided to keep on using my camp toilet.

In fact, we've been composting our "humanure" for over two months now; our flush toilet has been replaced with a handsome varnished platform with conventional toilet seat and a simple 5-gallon plastic pail.

My husband is a passionate organic gardener, at his happiest with a shovel in his hand, and he's already coveting the new compost. He's even wondering if the neighbors might consider making a contribution. I'm just grateful the kids are grown and moved out, because they'd have a thing or two to say.

As a final note, I'll reveal that my big worry about being bored was completely off-base. Three friends, Sally, Pat and Peg, dropped by the evening of our Practice Day, just after Larry and I finished our dinner of handmade tortillas, home-grown sprouts and a tasty rice/soy casserole. By candlelight, in front of a flickering fire, we talked late into the evening, with no interruptions and nobody hurrying, savoring each other's company. Sally later shared with me that the evening reminded her of her childhood. In the 1920s, when she was a young girl, they had no TV and no radio. After dinner family and friends sat around and talked for hours. They practiced the art of conversation.

The next day, still unplugged, we took a long walk, I read the paper by the window, finished a small knitting project, a neck-warmer, took a nap. I didn't really miss the loss of the telephone, computer, fax, e-mail and answering machine. As it got closer to the time when I could plug in again, I felt an upwelling of sadness. I didn't want to go back to my bright, noisy, hurry-up life.


{Veteran writer and publisher Judy Laddon is editor of Awakening: The Upside of Y2K. She founded Y2K Neighborhood, a citizen preparedness group, and serves on the Spokane City/County Y2K Task Force. She can be reached at 509-624-3177 or Her book is available through or local bookstores.}
Recycling Agricultural Wastes to Produce Hot Water
by Ole Ersson

Abstract. Two composting systems which use waste biomass (such as kitchen refuse and agricultural wastes) and human wastes for heating water are described. Since they are simple and inexpensive to construct, use widely available materials, and require minimal technical expertise, they may be ideal for developing nations. When properly constructed they require minimal maintenance, are free of odors, and pose no public health hazard. One system has been constructed and has been producing hot water for household use in Oregon for 2 months. A second more simple design is proposed. Inputs are: cold water, waste biomass, and human waste. Outputs are: hot water and compost. Materials required: wire or woven fencing and piping.

Composting. Composting is a time-honored process for the conversion of agricultural or gardening wastes into fertilizer. It is a cornerstone of organic gardening. The process is simple and requires little expertise. Most gardeners and farmers understand that by accumulating waste biomass in a central location the natural decomposition process is accelerated. Biomass consists of kitchen waste (inedible portions of fruits and vegetables, such as peels; spoiled food), agricultural or forestry wastes (weeds, prunings, and the remains of crops that have been harvested, such as corn cobs or husks removed during a milling process), and manures. The compost process consumes these waste materials, producing valuable fertilizer and improving garden hygiene. When properly constructed and maintained, it is odorless and free of vermin. Additionally, as anyone knows who has seen composting in action, an important by-product is heat.

The role of nitrogen and carbon in the compost process. The living systems which decompose matter require carbon-rich matter and protein (which contains nitrogen) in their food (substrate). Carbon provides energy for metabolic processes and is found in the structural matrix of plants (the cellulose in wood or plant stalks). Nitrogen provides a source of amino acids to construct the protein enzymes necessary to convert carbohydrate into energy. It is found primarily in other plant parts, such as leaves, and in animal matter or manure. Nitrogen-rich materials tend to be dense, non-porous, and decompose anaerobically and with little release of heat, often producing foul odors and attracting insects. However, when enough carbon is added to nitrogen-rich materials, a porous matrix is formed with a large surface area upon which microbes can multiply. The resulting decomposition process becomes aerobic, releasing much heat, and prevents insect infestation and unpleasant odors. An additional benefit is the thermal destruction of pathogens, such as viruses and parasites. In practice, this means a clean, aesthetically pleasing process.

The chemical decomposition consists of the oxidation of the carbon-hydrogen molecular bond. This releases carbon dioxide, water, and energy in the form of heat. It is the same chemical process which occurs when wood is burned. However, living systems are able to do this at lower temperatures by using enzymes as catalysts.

A composting hot water heater. I would like to describe a composting system I built in Oregon that uses composting principles to supply all the household hot water for my family of 2 adults and 3 children. The primary input in this process is waste biomass from tree pruning businesses. It consists of branches pruned from hardwood or coniferous trees that have been coarsely ground by chipping machines. This material is carbon-rich (i.e., contains mostly wood) and nitrogen-poor (i.e., contains few leaves) and by itself decomposes slowly. To this we add nitrogen-rich kitchen and garden wastes, additional garden and yard wastes from the community such as leaves and lawn clippings, and fecal matter and urine (humanure) collected in our toilet. Combining these two types of materials greatly accelerates decomposition and heat production.

Importance of adequate biomass. Proper composting requires adequate mass to create an environment suitable for bacterial growth. Small amounts of vegetation will decompose slowly and produce little heat which is rapidly dissipated. This favours fungal growth which is why fungi are the primary decomposers in nature. However, when adequate mass is brought together, as in a compost pile or bed, sufficient heat is produced to deter fungal growth and favour heat-tolerant bacteria. The mass serves not only as a substrate for heat production, but also as an insulator for the environment in the interior. The outer surface is at ambient temperature; the temperature of the substrate increases until it reaches its maximum in the interior. In our compost bed, we have measured the interior temperature at 130 degrees Fahrenheit.

A waterless toilet provides valuable nitrogen. In our household system we use humanure as a valuable source of nitrogen. We collect it with a simple water-free toilet consisting of two five-gallon buckets and a conventional toilet seat. One bucket is used as the receptacle and is fitted with a removable seat on a flange. A second contains wood chips or sawdust, which, after each use, is added in a thin layer to the first to cover and seal odors. When the first bucket is filled, the seat is transferred to a second bucket which is then empty and becomes the new receptacle. The nitrogen-rich humanure is then added to the compost bed. To maintain aesthetics and for proper hygiene, it is always important to cover any additions to a compost bed with a clean layer of woody or other high-carbon material.

Extracting heat with a heat exchanger. If sufficient mass is present, heat can be drawn off by a simple heat exchanger. We have installed such a heat exchanger in the form of a coil of flexible plastic pipe embedded in the interior of our compost bed. Heat from the decomposition penetrates the pipe, thereby heating water which circulates inside. Cold water enters at one end of the pipe. When a faucet is opened at the other end, hot water will emerge until the incoming cold water replaces the heated water and cools the pipe. Then it is necessary to wait for the heat from the hot mass to again penetrate the pipe and heat the fresh cold water. The amount of hot water that can be drawn off in one "serving" depends on the diameter and length of the pipe. In our system we used a 1.5 inch diameter pipe 100 feet long. This provides a reservoir of hot water of approximately 9 gallons, enough for several quick showers or a single load of laundry.

Using heat to warm a greenhouse. In designing my composting system, I wanted to utilize the heat for both household hot water and to warm a greenhouse in Oregon's cool winter. Therefore, I decided to use a large amount of biomass, which is available free from local companies. I used a three-foot deep layer of the primary substrate (ground tree prunings) as the floor of the greenhouse, whose dimensions are approximately 16' by 28'. This mass is contained within walls constructed of three layers of straw bales, stacked together like bricks, which are also available as a free agricultural waste product in Oregon. I used straw bales because they also perform well as a foundation for the sides and roof of a greenhouse. I plan to construct the roof this Fall by using parallel arches which span the two sides and which will have transparent plastic sheeting draped over them to enclose the interior space, protecting it from the cold outside. The compost bed floor is constantly releasing heat into the space above it. The straw bale sides and plastic roof should help retain this heat in the greenhouse. The heat exchanger is embedded in the deep layer of compost which makes up the floor. Therefore, the heat from the decomposition process provides heat for both water (which is pumped into the house) and to heat the space of the greenhouse itself.

Results. Preliminary measurements (at two months old) showed that the initial 10 gallons of water emerging from the heat exchanger was greater than 130 degrees Fahrenheit. After this, it gradually cooled down to about 100 degrees as it reached 20 gallons. The water entering the heat exchanger was about 45 degrees, demonstrating that the compost beds heated the water more than 80 degrees! We have been using the water it generates for all household needs since its construction. Since installing our system about two months ago we have been able to disconnect our electric hot water heater and still have 24-hour hot water. The space heating ability of the composting process has not yet been tested. No unpleasant odors are present.

A simpler design. I would like to propose the following much simpler design for the generation of hot water alone from waste biomass. A "bare-bones" system would consist of a structure that contains the compost bed in the form of a cylinder with sides constructed of woven wire fencing. No posts or other structural materials would be required because the pressure of the biomass pushing out against the fencing will hold the fencing vertical. Embedded in this is a coil of plastic or other pipe which serves as a heat exchanger. Ideally, this will be pressurized water which can then be delivered to where it will be used. The biomass consists of whatever high-carbon material is available in the locale. The size of the cylinder will depend on the diameter of the coils of the pipe. I would suggest that the sides of the cylinder be one to two feet outside the coiled pipe. This will ensure that sufficient insulation exists to maintain the pipe at a high temperature. The 1.5 inch pipe I used came in coils about 6 feet in diameter. Thus, a cylinder approximately 10 feet in diameter and 4 feet or more high would accommodate this size pipe. The biomass decomposition begins when a source of nitrogen (such as leafy matter or manure) is added.

Costs. The major cost of this project consists of the heat exchanger. The plastic pipe described above cost $45 in Oregon. Additional parts to connect to an existing plumbing system (valves, supply pipe) could be expected to cost about $10-20. The only other cost is the fencing or other support to contain the biomass in a cylindrical shape. A 35 foot length of woven wire fence 5 feet high costs about $30 in Oregon. Thus the total budget for this project is less than $100.

The future. I estimate we are actually extracting only a small percentage of the heat produced (several tens of gallons of hot water per day). One Peace Corps volunteer suggested that we could better utilize the heat by constructing a jacuzzi. Indeed, a simple pool could be easily constructed by excavating a depression in the middle of the compost bed and lining it with a heavy plastic or rubber sheet to contain the water. Then, by circulating the water in this pool back into the heat exchanger when it cooled below a desired level, a compost-powered hot tub could be built. I believe the water in a hot tub is typically 105 degrees. Therefore, the temperatures achieved by composting should be adequate. Only experimentation will tell! I invite anyone attempting to harness the power of composting in novel ways contact me with a progress report. The possibilities are manifold!

A similar version of this report was submitted to Peace Corps, Guatemala, Guatemala City, in July 1994.

Instructions for building the composting toilet can be found on: Other sustainable technologies can be picked up at:




Recently we came upon a history of the management of human excreta -- urine and feces -- starting back in the mists of time and working forward to the present day.[1] It turns out that this unlikely topic can tell us something important about the way humans make environmental decisions. For that reason, we're going to recap the story here. The original author, Abby A. Rockefeller, deserves credit for all the original work, though not, of course, blame for any of our lapses or misinterpretations in the retelling. Where we have supplemented Ms. Rockefeller's history with additional facts, they appear inside square brackets.

*Humans began to lead a settled life, growing crops to supplement hunting and gathering, only about 10,000 years ago. For all time before that, humans "deposited their excreta -- urine and feces -- on the ground, here and there, in the manner of all other land creatures." The soil and its communities (including plants, small animals and microorganisms) captured almost all of the nutrients in animal excrement and recycled them into new components for soil. In this way, the nutrients were endlessly recycled within the soil ecosystem and largely kept out of surface water.

As a result, what we call "pure water" is low in nutrients, particularly the major nutrients nitrogen and phosphorus. Because these conditions have existed for a very long time, life in lakes, rivers, and oceans is accustomed to the relative absence of these nutrients. Over the past couple of billion years, life has flourished in this low-nutrient environment, growing complex and interdependent in the process -- an aquatic condition we call "clean" and "healthy."

When a body of water is suddenly inundated with nutrients -- especially nitrogen and phosphorus -- things change drastically. One or a few organisms flourish and begin to crowd out the others. We can all recall seeing a body of water that is pea-soup green from overgrowth of algae. Such a water body is clearly sick, choked, its diversity vastly diminished.

Today, much of the surface water of the planet is in a state of ill health because of misplaced nutrients. And a main contributing culprit is misplaced human excreta.

Long ago, human civilizations split into two camps regarding the management of excreta. Many Asian societies recognized the nutrient value of "night soil" (as it became known). For several thousand years, and up until very recently, Asian agriculture flourished by recycling human wastes into crop land.

The opposing camp, particularly in Europe, had ambiguous feelings about human waste -- was it valuable fertilizer or was it a nasty and embarrassing problem to get rid of?

In Europe, a pattern evolved: The first stage was urinating and defecating on the ground near dwellings. As population density increased, this became intolerable and the community pit evolved. For privacy, this evolved into the pit privy or "outhouse" -- a privacy structure atop a hole in the ground. Despite what many people may think, the pit privy is not environmentally sound -- it deprives the soil of the nutrients in excrement, and by concentrating wastes it promotes pollution of groundwater by those same nutrients.

Before the advent of piped water in the late 18th century, European towns stored excreta in cesspools (lined pits with some drainage of liquids) or in vault privies (tight tanks without any drainage). The "night soil" was removed by "scavengers" and was either taken to farms, or dumped into pits in the ground or into rivers. In general, Europeans never developed a clear and consistent perception of the nutrient value of excrement, as Asians had done.

In ancient Rome, the wealthy elite had indoor toilets and running water to remove excrement via sewers. Later, European cities developed crude sewer systems -- usually open gutters but sometimes covered trenches along the center or sides of streets -- though they had no running water until the 18th or even 19th centuries. The putrefying matter in these stagnant ditches did not move until it rained -- thus the name "storm sewers" -- and many cities prohibited the dumping of human wastes into such sewers.

With the advent of piped water, things changed dramatically. In this country, the first waterworks was installed in Philadelphia in 1802 and by 1860 136 cities were enjoying piped water systems. By 1880, the number was up to 598. With piped water, per-capita water use increased at least 10-fold, from 3-5 gallons per person per day to 30-50 gallons per person per day or even more.

Water piped into homes had to be piped out again. This caused cesspools to overflow, thus increasing the problems of odors and of water-borne diseases. To solve these problems, cesspools were connected to the city's crude sewer systems which ran along the streets. The result was epidemics of cholera. In Paris in 1832, 20,000 people died of cholera. Around the world, the combination of piped water and open sewers has consistently led to outbreaks of cholera.

To solve this problem, engineers designed closed sewer systems, pipes using water as the vehicle for carrying away excrement. This solution engendered a debate among engineers: some wanted to return sewage to agricultural land, others argued that "water purifies itself" and wanted to pipe sewage straight into lakes, rivers, and oceans. By 1910, the debate was over and sewage was being dumped into water bodies on a grand scale.

In the cities, cholera epidemics abated. However, cities drawing their drinking water downstream from sewage discharges began having outbreaks of typhoid. This engendered another debate: whether to treat sewage before dumping it into water bodies used for drinking, or whether to filter drinking water. Public health officials favored treating sewage before dumping it; sanitary engineers favored dumping sewage raw and filtering water before drinking. The engineers prevailed. As cities began to filter and disinfect their drinking water, typhoid abated.

Throughout the 20th century, the U.S. and Europe industrialized rapidly. Industry developed a huge demand for low-cost waste disposal, and sewers were the cheapest place to dump because the public was paying. As the pressure for greater waste disposal capacity increased, industrialized nations allocated vast sums of money to construct centralized sewer systems to serve the combined needs of homes and factories.

As a result, the nutrients in excrement became mixed with industrial wastes, many of them toxic. So by the 1950s, essentially every body of water receiving piped wastes was badly polluted with a combination of excessive nutrients and toxicants. This led to a demand to treat wastes before dumping them into water. Thus began the "treatment" phase of the "get rid of it" approach to human waste.

As centralized sewer systems evolved, first came "primary treatment." This consists of mechanically screening out the dead cats and other "floatables." All other nutrients and toxic chemicals remain in the waste water that is discharged to a river or ocean.

Next came "secondary treatment" which speeds up the biological decomposition of wastes by forcing oxygen into them, by promoting bacterial growth, and by other means. This is an energy-intensive process and therefore expensive. Unfortunately, it, too, leaves many of the nutrients and toxic chemicals in the discharge water.

[The Congressional Research Service recently estimated that the federal government spent $69.5 billion on centralized sewage treatment plants, 1973-1999.

Despite this huge expenditure, the Congressional Research Service said in 1999, "States report that municipal discharges are the second leading source of water quality impairment in all of the nation's waters (rivers and streams, lakes, and estuaries and coastal waters). Pollutants associated with municipal discharges include nutrients..., bacteria and other pathogens, as well as metals and toxic chemicals from industrial and commercial activities and households."[2]]

To the extent that primary and secondary treatment are successful, they move nutrients and toxicants (combined) into a new form: sludge. Sludge is the de-watered, sticky black "cake" created in large quantities by modern sewage treatment plants. Sludge contains everything that can go down the drains in homes and industries and which a treatment plant is able to get back out.

In the FEDERAL REGISTER November 9, 1990, U.S. Environmental Protection Agency describes sludge this way:

"The chemical composition and biological constituents of the sludge depend upon the composition of the wastewater entering the treatment facilities and the subsequent treatment processes. Typically, these constituents may include volatiles, organic solids, nutrients, disease-causing pathogenic organisms (e.g., bacteria, viruses, etc.), heavy metals and inorganic ions, and toxic organic chemicals from industrial wastes, household chemicals, and pesticides."

Industry is currently using 70,000 different chemicals in commercial quantities; any of these may appear in sludge. About 1000 new chemicals come into commercial use each year, so any of these, too, may appear in sludge. A description of the toxicants that may be found in sludge would fill several books. The U.S. General Accounting Office has reported -- not surprisingly -- that municipal sludge contains radioactive wastes (from both medical and military sources).[3]

With hundreds of sewage treatment plants producing toxic sludge in mountainous quantities, the next question was, what in the world to do with it?

For many years, coastal cities dumped sewage sludge into the oceans, where it created large "dead zones" that could not support marine life. Other communities dumped their sludge into landfills, where it could pollute their groundwater. Still others incinerated their sludge, thus creating serious air pollution problems, then landfilled the remaining ash or simply heaped the ash on the ground for the wind to disperse.

In 1988 Congress outlawed the ocean dumping of sewage sludge. At this point, many communities faced a real waste crisis. There was no safe (or even sensible) place to put the mountains of toxic sludge that are generated every day by centralized sewage treatment systems.

It was at this point in history that U.S. Environmental Protection Agency (EPA) -- feeling tremendous pressure to "solve" the sludge disposal problem -- discovered that sewage sludge is really "night soil" -- the nutrient-rich product that has fertilized crops in Asia for several thousand years. EPA decided that the expedient thing to do with sewage sludge was to plow it into the land.

Shortly after 1992, when the ban on ocean dumping went into effect, EPA renamed toxic sludge "beneficial biosolids," and began aggressively campaigning to sell it to the American people as fertilizer. (See REHW #561.)

[To be continued]


[1] Abby A. Rockefeller, "Civilization and Sludge: Notes on the History of the Management of Human Excreta," CURRENT WORLD LEADERS Vol. 39, No. 6 (December 1996), pgs. 99-113. Ms. Rockefeller is president of the ReSource Institute for Low Entropy Systems, 179 Boylston St., Boston, MA 02130; telephone (617) 524-7258.

[2] U.S. General Accounting Office, NUCLEAR REGULATION; ACTION NEEDED TO CONTROL RADIOACTIVE CONTAMINATION AT SEWAGE TREATMENT PLANTS [GAO/RCED-94-133 (Washington, D.C.: U.S. General Accounting Office, May 1994).

[3] Claudia Copeland, WASTEWATER TREATMENT: OVERVIEW AND BACKGROUND [98-323 ENR] (Washington, D.C.: Congressional Research service, January 20, 1999). Available at: http://-

Continuing from last week, we are retelling the history of the management of human excrement as originally narrated by Abby A. Rockefeller.[1] Where we have added new facts to Ms. Rockefeller's original history, they appear inside square brackets.

*To recap where we are: Cities began to provide running water into homes in the early 19th century. Water piped into homes had to be piped out again, often into open sewer ditches running in the streets. Outbreaks of cholera followed. A debate ensued: should sewage be transported back to farms, where the nutrients had originated, or should it be disposed of by dumping it into bodies of water? Although many cities for a time transported sewage to farms, by 1920 most sewage was being piped directly into bodies of water. This was a crucial choice.

Once the network of sewer pipes began to grow, industry saw these public pipes as a cheap place to dump industrial wastes. As a result, corporations began to dump all manner of toxicants into the nutrient- rich sewage stream. This was another crucial choice. Once they were mixed together, nutrients and industrial poisons could not be separated at any reasonable price. Therefore the whole mess became a toxic waste disposal problem and excrement lost its value as a fertilizer. Dumping it into water bodies accelerated.

By the 1950s, most of the nation's waterways were badly contaminated with a combination of nutrients and toxicants. This gave rise to a demand for treatment of waste prior to disposal. Pipes that used to carry toxic sewage into streams and oceans now began to carry it into centralized "wastewater treatment plants" or "publicly owned treatment works" (POTWs).

Wastewater treatment plants remove the solids and some of the chemicals, creating a black, mud-like "sludge" in the process. It's a trade-off: improved wastewater treatment means cleaner discharge water but it also means more sludge and worse sludge (more toxic). Now a new, and truly intractable, problem appears: what to do with mountains of toxic sludge?

Communities with access to the ocean began dumping sludge there. New York dumped its sewage sludge 12 miles offshore; when that place developed obvious contamination problems, the dumping was moved to a spot 106 miles offshore, where, to no one's surprise, contamination soon developed.

The use of water to carry sewage, and the use of centralized wastewater treatment plants, had great political appeal for several reasons. Most political authorities tend to favor centralized solutions because they basically don't trust people to handle their own problems. Secondly, as we have noted, industry needed a cheap place to dispose of its wastes. [In 1997, according to the Congressional Research Service, industry "dumped 240 million pounds of wastes with hazardous components" into municipal sewers.[2]] Third, and perhaps most important, laying sewer pipes and building centralized sewage treatment plants is extremely costly and engineering firms receive 20% of the initial cost. [Between 1970 and 1993, the federal government appropriated $69.5 billion for sewage construction projects. The Congressional Research Service recently estimated that between now and the year 2016 (17 years), the federal government will spend another $126 billion on sewage projects. [2] These are serious amounts of money.] Only the Federal Highway Administration [and the military] spend more public money on construction. [If even a small fraction of this sewer money is kicked back at election time by consultants, lawyers, investment bankers and engineering firms, it can go a long way toward keeping the present crop of politicians in office.]

In the 1970s, many environmentalists and public health officials favored centralized sewage treatment because it seemed to offer an improvement over dumping raw wastes into waterways. The Clean Water Act of 1977 was essentially a sewering act. Everyone was then locked into centralized wastewater treatment systems.

In 1988, Congress discovered that sludge dumping in the oceans was harming marine life, and the practice was banned as of 1992. This created a massive problem for American cities: [11.6 billion pounds of sludge (that's the dry weight, not counting the water it contains[3]) has to go somewhere, year after year.]

At that moment, EPA decided that the U.S. now needs to mimic 100 generations of successful farmers in Asia, returning human excrement to farmland.

However, EPA has overlooked two important differences between modern sewage sludge and traditional "night soil" (unadulterated human waste):

1) Most of the nitrogen in human waste is in the urine and is water- soluble, so it is not captured in the sludge. Therefore, if sludge is going to substitute for commercial fertilizer, you have to use a lot of it to get enough nitrogen. And (2) when you add a lot of sludge to soil, you are also adding a lot of toxic metals and a rich (though very poorly understood) mixture of organic chemicals and, very likely, radioactive wastes as well.

EPA has addressed the toxic metals by telling farmers to add lime to their soil along with the sewage sludge, to prevent the soil from becoming acidic. If soil turns acidic, then toxic metals begin to move around, either leaching down into groundwater or moving upward into the crops (which, by definition, are part of some food chain). If soils are alkaline (the opposite of acidic), the metals move more slowly.

[What EPA has overlooked is the fact that ordinary rain is slightly acidic, not counting the excess acidity provided by "acid rain." Normal rain drops falling through the atmosphere dissolve small amount of carbon dioxide, forming carbonic acid. Normal rain has a pH of 5.6 whereas 7 is neutral. Therefore, if soils are not kept alkaline by the regular addition of lime, sooner or later normal rain will begin to leach excess metals out of many soils. The only way to prevent this is to keep the excess metals out of soils in the first place.]

In sum, plowing sewage sludge into soils is essentially guaranteed to harm many of those soils as time passes. [See REHW #561.] [As we know from the ancients who poisoned their soils with irrigation salts, a nation that poisons its farmland is a nation that doesn't have a long- term future.]

A series of bad decisions made during this century has brought us to an impasse: sewage sludge is unmanageable because you can't know from day to day what is going to be in it, and so you cannot monitor its contents.[4] (Even if you could manage the scientific problems inherent in monitoring an unknown mixture of unknown substances, as a practical matter there isn't any government agency with enough staff to monitor the nation's sludge.)

Therefore -- as heroic a task as this may seem -- it is time to re- think centralized water-carriage sewage treatment systems. The present systems were not designed to produce useable products and therefore the DESIGN of present systems is the root of the problem.

Three policy goals are needed: (1) Sewer avoidance (stay off or get off water-carriage, centralized sewer systems). (2) Promote low-cost, on- site resource recycling technologies, such as composting toilets, that avoid polluting water and preclude wasting resources. (3) Price water right so that the market works to keep it clean, not contaminate it with excreta.[4]

[For individual households, real solutions are already available: zero discharge household waste systems. An excellent new book by David del Porto and Carol Steinfeld, THE COMPOSTING TOILET SYSTEM, will dispel any fears you may have that composting toilets are a step backward.[5] With microflush toilets and vacuum-flush toilets now readily available, you can have the bathroom of your dreams, yet compost your household wastes into an odor-free product that is entirely satisfactory as agricultural fertilizer. These days, there are companies that will manage the system for you, including removing the compost. Your household waste system can be installed, maintained, and managed by professionals, just like your electrical and heating systems.

But what about apartment buildings and office buildings in cities? Although we know of no one who has applied it, the technology certainly exists for manufacturing building-scale waste systems based on anaerobic digesters, which would produce methane gas and fertilizer. As Abby A. Rockefeller said recently in an interview, "Surely, human ingenuity can do this." Such systems would be cheaper than current sewage systems because they wouldn't require miles of underground pipes to connect to a centralized sewage treatment plant, and they would conserve hundreds of billions of gallons of water each year.

[Every time we flush the toilet, 3.3 gallons of drinking water are degraded. At 5.2 flushes per day (average), each of us presently degrades 6260 gallons of drinking water each year to flush away our 1300 pounds of excrement -- 1.6 trillion gallons of water per year in the U.S.]

Naturally, we would need to keep toxicants out of these composting systems, but that has always been true (even though we have ignored this fact) and we might as well face up to it now. Toxic household products will have to be phased out as part of any plan for sustainable living.

Toxic industrial wastes should be managed by the industries that make them, not dumped into the environment that sustains all life. Unusable wastes are a sure sign of inefficiency.

Lastly, what to do with today's mountains of toxic sludge? Obviously they must be handled as hazardous wastes because that's what they are. [Probably above-ground storage in concrete buildings is the only satisfactory solution at the present time. (See REHW #260.)]

[You say we can't do any of this because we've been doing it another way for 100 years? Ask yourself, what kind of people would dump their excreta into their drinking water in the first place? And what kind of people, faced with workable, cheaper, more environmentally sound alternatives would continue to insist that dumping their excreta into their drinking water is the only way to live?]

-Peter Montague (National Writers Union, UAW Local 1981/AFL-CIO)


[1] Abby A. Rockefeller, "Civilization and Sludge: Notes on the History of the Management of Human Excreta," CURRENT WORLD LEADERS Vol. 39, No. 6 (December 1996), pgs. 99-113. Ms. Rockefeller is president of the ReSource Institute for Low Entropy Systems, 179 Boylston St., Boston, MA 02130; telephone (617) 524-7258.

[2] Claudia Copeland, WASTEWATER TREATMENT: OVERVIEW AND BACKGROUND [98-323 ENR] (Washington, D.C.: Congressional Research Service, January 20, 1999). Available at: .

[3] Gary D. Krauss and Albert L. Page, "Wastewater, Sludge and Food Crops," BIOCYCLE (February 1997), pgs. 74-82. Krauss was staff director for the National Research Council study, USE OF RECLAIMED WATER AND SLUDGE IN FOOD CROP PRODUCTION (Washington, D.C.: National Academy Press, 1996).

[4] Robert Goodland and Abby Rockefeller, "What is Environmental Sustainability in Sanitation?" IETC'S INSIGHT [newsletter of the United Nations Environment Programme, International Environmental Technology Centre] Summer, 1996), pgs. 5-8. The International Environmental Technology Centre can be reached at: UNEP-IETC, 2-1110 Ryokuchikoen, Tsurumi-ku, Osaka 538, Japan. Telephone: (81-6) 915-4580; fax: (81-6) 915-0304; E-mail:; URL: See also Abby A. Rockefeller, "Sewage Treatment Plants vs. the Environment," an unpublished paper dated September, 1997. And: Abby A. Rockefeller, "Sludge is Sludge; The Illusion of Safety," an unpublished paper dated June 26, 1996. Ms. Rockefeller is president of the ReSource Institute for Low Entropy Systems, 179 Boylston St., Boston, MA 02130; telephone (617) 524-7258.

[5] David Del Porto and Carol Steinfeld, THE COMPOSTING TOILET SYSTEM BOOK (Concord, Mass.: Center for Ecological Pollution Prevention, 1999). ISBN 0-9666783-0-3. See http://www.ecological-; $29.95 plus $3.30 shipping ($12 overseas shipping) from: Center for Ecological Pollution Prevention, 50 Beharrell St., P.O. Box 1330, Concord, Mass. USA 01742. Phone (978) 369-9440. Fax: (978) 368-2484. E-mail: See also: Carol Steinfeld, "Composting Toilets Come to the Rescue in Massachusetts," BIOCYCLE (April 1996), pgs. unknown. See And see: Carol Steinfeld, "Composting Toilets Emerge as Viable Alternatives," Environmental Design & Construction (July/August 1998), pgs. unknown. See

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