nvasive), needing no irrigation. Otherwise, for most ground cover, small amounts of efficient drip irrigation suffice. Some examples: creeping juniper, moss pink, houseleek, cushion spurge, saltbush, kinnickinnick, periwinkle. When orchards are established their deep roots need little watering to provide fine food. Rooftop Catchment: Millions of gallons/year fall on city roofs. When all this is collected in eaves, filtered then held in reservoirs, we’ll gain secure direct supply. Much can be also be distilled directly for drinking, in rooftop greenhouses. Depaving: Millions of gallons/year of fresh rainwater falling on streets and parking lots are mixed with automobile toxics and fed through storm drains to the ocean. As the city is rebuilt to become more mobile with fewer cars, hundreds of square miles of smothered land will be freed to feed orchards and gardens, by absorbing rain. This will freshen air and revive groundwater. See FOOD for introduction to depaving machines. Recharge Basins: Diversion of rainwater and river overflow to storage in absorptive terrain is ready for dry seasons. There are already several major basins in the Los Angeles area; there can be more in each neighborhood. Greywater: Household recycling of sink and bathwater. Recycling Onsite, industrial and institutional: Cooling towners. Biodegradable Soaps: Contain no phosphate and is made up of biodegradable surfactants. Efficient Household Utilities: Low-flow showerheads, faucets, etc.
Compost Toilets: Here’s the biggest cultural shift. Shitting into clean water will be replaced by dry toilets that produce clean, sweet-smelling earth. We will no longer contaminate drinking water, groundwater and ocean water with human waste, nor waste millions of gallons of oil to pump water in and poop out. We will instead convert this waste into a healthy resource. Since half of Los Angeles’ household water use goes to flushing toilets, we’ll double the available local water supply and halve the need to import. Composting toilets are approved by the U.S. National Science Foundation and most local Departments of Health. They’re legally a plumbing fixture in several states. They’ve become common in state parks and replaced septic tanks in many in rural areas.
The reason that compost toilets don’t smell bad, and that the stuff in them is not hazardous, is that there are air pipes within that promote decay by air-breathing (aerobic) bacteria. Their byproduct is odorless methane gas, and pathogenfree residue, containing phosphorous, potassium, nitrogen, calcium and manganese. This contrasts with old-fashioned (but common worldwide) pit privies-- shitters-- that contain no air. The byproduct of their non-airbreathing (anaerobic) decay is hazardous muck and sulphurous stench. There are many styles of compost toilet. The model I consider best suited for broad urban use is the carousel-type unit. It completely separates hazardous fresh turd from safe decayed turd, by dividing the dump chamber into four parts. When one quadrant is filled, the chamber is rotated to an empty chamber. After several months or years the full chamber is unloaded, though by this time 95% of deposit has evaporated. Can we learn to love and use compost toilets? For centuries city dwellers poured their crap from windows onto streets, and pooped into pits. Humans then learned to use flush toilets, which are barbaric as well. Now we can learn to adopt the best of both poop worlds.