Will cities in the future be re-designed to function "like sponges," to cope with droughts that will only become more severe thanks to climate change?
A recent NPR report takes Los Angeles as an example of how urban water infrastructure will have to change ... moving away from aqueduct systems first used in ancient Rome ... and soon:
If you were to follow a drop of rain from the sky and onto an LA sidewalk, eventually you'd end up at the mouth of the Los Angeles River, which isn't really a river. Engineers turned it into a narrow concrete channel in the 1940s. Today, it's more like a 51-mile-long bathtub that empties out at the port of Long Beach.
But really, it's a flood-control channel, which is why signs on the river prohibit anything recreational. In a rainstorm, all that runoff from the sewers could surge through the channel.
The problem today is the city needs that rain. It can't afford to just send it out into the ocean anymore. Almost 80 percent of California is in extreme drought. (That's a technical term, just one notch shy of "exceptional" drought.)
Los Angeles' Elmer Avenue has been designated an "experimental block," to test out ways in which every drop of rain can be collected, used, and re-used: "along each sidewalk is what's called a bioswale — a gully filled with drought-resistant plants. When it rains, the water collects and filters down into cisterns buried below the street." In an average year, just the one block of Elmer can collect enough water for 30 families.
Other ideas include building houses with roofs designed to capture as much rain as possible, and designating different waters different "grades," like not using drinkable water to flush toilets.
A driving force behind this movement is the nonprofit Arid Lands Institute, whose co-founder Hadley Arnold stresses the importance of its cause:
"The ace in our species pocket is the ability to innovate. And I think the single biggest question in front of us right now is the rate at which we do it. Can we do it fast enough, given the urgency?"
Image via Gallery Hip.