"The nutrients in all that effluent, much of it from flush toilets, if converted to fertilizer would be the equivalent of 200 tons of 7-14-12 fertilizer (7% nitrogen, 14% phosphorus, 12% potassium). Each ton of fertilizer when applied to soil would provide nutrients to grow 25 tons of vegetables. Thus each day L.A.'s waste provides the nutrients to grow 5,000 tons of vegetables, enough to provide everyone in Los Angeles with a pound or two of fresh produce daily."
-Sim Van der Ryn, The Toilet Papers