Definition of flood: “too many people on wet ground”.
Definition of drought: “too many people on dry ground”.
There’s a theme…
No, the lynchpin is definitely not groundwater, though that might be what Garcetti’s crowd is saying. That’s another dead end.
Groundwater does not recharge adequately. So you pump it for a few years, dig the wells deeper once or twice, and then it is gone. Meanwhile, housing tracts will have caved into the ground above the newly created empty spaces, and the sea has seeped into deep aquifers where they have been pumped near the sea–and Los Angeles is mostly coastal floodplain, remember.
It is not even a matter of too many people–though sure, if you insist on putting everybody in one place, the problems tend to become more critical.
No, the major problem is straightforward. Los Angeles has a century or so worth of infrastructure dedicated to rushing its occasional rains to sea with as little interaction with the surrounding landscape as possible, just as though no one in the western states had ever heard the words “drought,” “fire,” or “flood.”
Any and all reasonable responses to California’s circumstance are diametrically opposed to this. Southern California is on the edge of a desert. It is a Mediterranean climate and gets almost all of its rain between December and March. Yet no one seems to draw the obvious conclusion: California has to store water for 9 or so months of the year.
One might imagine that this cannot be done. Actually, it is not that difficult except that it requires some major re-adjustment in assumptions–which of course is a difficulty not to be minimized.
Here’s the story.
- All across the southland are enormous rooftops. These need gutters and tanks or pipes to lead to converted swimming pools to be used for water storage, as ponds. The water is better than what you get through the pipes now, so it should be used for drinking, cooking and washing.
- Greywater systems can release kitchen and wash water that is not used to flush toilets directly to soil and plants
- Greywater can also be rerouted to flush toilets. No toilet need be flushed with fresh water, nor its water lost.
- Flush toilets need not drain to the sea, where they pollute the oceans and beaches. They can be directed to artificial wetlands, which requester carbon and recycle human waste as fertility. This is already done in large parts of Australia, including urban environments. Well done, it is far more sanitary than current practice, and it stinks less, too.
- Lawns should largely be removed and replaced by gardens favoring xeric perennials, including trees, cacti, and succulent ground cover like iceplant. These are productive, attractive, and use a fraction of the water needed by lawns.
- Deciduous trees should shade the south and west walls of buildings
- Solar panels should be placed so as to shade roofs
- Curbs and driveways can be cut to allow water to flow into landscape at yard after yard, and other steps should be taken to direct all runoff from roads into the landscape
- Slopes can be swaled or plowed on contour to allow water to stop, spread, and soak into the soil
In this way, Los Angeles can not only reduce its pollution and supply all of its own water, but grow most of its food within in the metropolitan area as well.
A very large portion of the Los Angeles area suburbs were built from the 40s through the 70s, were not built to last, have relatively large lots, and are ripe for retrofit. Los Angeles could be a warning example of “what went wrong in the 20th Century,” or it could be an example of how thoroughly a population can catch itself and change direction.
It’s nice that Garcetti & Co have caught on to some of this. The process will need most of it to work.