Last week, we saw an interactive map showing which water districts are soaking up the most water per capita. A recent study from a student and faculty member at UCLA took a different approach to drought-watching: they looked at residential water usage and income by census tract. What the researchers found was that "Wealth was the most reliable predictor of water use. The wealthy used more than three times the water of nonwealthy people," California Center for Sustainable Communities at UCLA Director Stephanie Pincetl tells Yahoo News.
Pincetl supervised the study on residential water use, which was done by a Ph.D. student at the university and used data from the LADWP for a period of ten years, plus satellite images. Contributing to the high water use of the rich is that they usually have more space to water. Pincetl says that more than 50 percent of water used in LA goes to "outdoor irrigation" —the lush lawns, flowering shrubs, a water feature or two. Considering that lot size, housing density, weather, and the age of dwellings are some of the factors that affect how much water people use, it makes sense that a newer, single-family home on a large lot is probably going to use a lot more water than a older duplex on a small lot.
Playa Vista and Venice were the only two 'hoods that are both affluent and conservative on water use. The final brief for the study says this is probably because Playa Vista is a relatively new community, built with higher densities and water-conservation in mind; Venice's low water consumption—the lowest of 13 neighborhoods surveyed—is chalked up to its relatively cool climate plus its smaller lot and home sizes.
The wealthy are also kind of immune to rate hikes, which are supposed to spur people to use less water. Pincetl says when rates are jacked up, it doesn't really affect richer people, who can afford to pay a little bit more to keep their yards green. "When rates went up by tier for water conservation, low-income people conserve more water — showing they are more price-sensitive to water rates than wealthy people," she says. Income plays such a big part in water usage that "a $1,000 increase in median household income would increase single-family water use by about 2 percent," according to the final brief. So even if a household isn't exactly rich, just a little bit more money in their communal coffers alters the way they use water.
In light of all this information, the study suggested several policy changes, including revising the current tiered system in place to charge consumers for water, separating indoor from outdoor water use by implementing dual meters, and setting up "reasonable" water budgets for households.
· Wealth is most reliable predictor of water use in Los Angeles: Study [Yahoo News]
· Final Brief - Residential Water Consumption in Los Angeles: What are the Drivers and are Conservation Measures Working? [CCSC]
· Mapping/Shaming the Most Water-Guzzling Places in SoCal [Curbed LA]