Rethinking the Home Water System

Photo credit: peasap/Creative Commons

U.S. President Theodore Roosevelt once noted that "civilized people ought to know how to dispose of the sewage in some other way than putting it into the drinking water."

The one-time use of water to disperse human and industrial wastes is an outmoded practice, made obsolete by new technologies and water shortages. Yet it is still common around much of the world. Water enters a city, becomes contaminated with human and industrial wastes, and leaves the city dangerously polluted. Toxic industrial wastes discharged into rivers and lakes or into wells also permeate aquifers, making water—both surface and underground—unsafe for drinking.The current engineering concept for dealing with human waste is to use vast quantities of water to wash it away, preferably into a sewer system, where it may or may not be treated before being discharged into the local river.

The "flush and forget" system takes nutrients originating in the soil and typically dumps them into the nearest body of water. Not only are the nutrients lost from agriculture, but the nutrient overload has contributed to the death of many rivers and to the formation of some 405 "dead zones" in ocean coastal regions.


A Better Sewage Solution?


As currently designed, India's sewer system is actually a pathogen-dispersal system. It takes a small quantity of contaminated material and uses it to make vast quantities of water unfit for human use. With this system, Narain says, both "our rivers and our children are dying." India's government, like that of many developing countries, is hopelessly chasing the goal of universal water-based sewage systems and sewage treatment facilities—unable to close the huge gap between services needed and provided, but unwilling to admit that it is not an economically viable option.

The Compost Alternative




Rose George, author of The Big Necessity: The Unmentionable World of Human Waste and Why It Matters, reminds us why the "flush and forget" system is an energy guzzler. One, it takes energy to deliver large quantities of drinking-quality water (up to 30 percent of household water usage is for flushing). Two, it takes energy--and lots of it--to operate a sewage treatment facility.

New Systems, New Opportunities




Individual industries facing water shortages are also moving away from the use of water to disperse waste. Some companies segregate effluent streams, treating each individually with the appropriate chemicals and membrane filtration, preparing the water for reuse. Peter Gleick, lead author of the biennial report The World's Water, writes: "Some industries, such as paper and pulp, industrial laundries, and metal finishing, are beginning to develop 'closed-loop' systems where all the wastewater is reused internally, with only small amounts of fresh water needed to make up for water incorporated into the product or lost in evaporation." Industries are moving faster than cities, but the technologies they are developing can also be used in urban water recycling.


Two household appliances—toilets and showers—together account for over half of indoor water use. Whereas traditional flush toilets used 6 gallons (or 22.7 liters) per flush, the legal U.S. maximum for new toilets is 1.6 gallons. New toilets with a dual-flush technology use only 1 gallon for a liquid waste flush and 1.6 gallons for a solid waste flush. Shifting from a showerhead flowing at 5 gallons per minute to a 2.5 gallons-per-minute model cuts water use in half. With washing machines, a European horizontal axis design uses 40 percent less water than traditional top-loading models.

The existing water-based waste disposal economy is not viable. There are too many households, factories, and feedlots to simply try and wash waste away on our crowded planet. To do so is ecologically mindless and outdated--an approach that belongs to a time when there were far fewer people and far less economic activity.

Adapted from Chapter 6, "Designing Cities for People" in Lester R. Brown, >Plan B 4.0: Mobilizing to Save Civilization (New York: W.W. Norton & Company, 2009), available on-line at
Read more about toilet tech:
I Have Seen the Future and it Flushes
After Smart Grids, Smart Sewage? Urine-Separating NoMix Toilet Gets Thumbs-Up in 7 European Countries
Waste Not, Want Not: The Future of Toilets

Tags: Drinking Water | Water Conservation

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