It’s been fashionable of late to decry the idea of rich people buying luxury condos in our cities, driving up rents and taking away affordable housing opportunities.  From a transit perspective, an influential study from TransForm showed that it’s best to locate affordable housing near transit if you want to boost ridership and lower greenhouse gas emissions.  Rich people, the study suggests, don’t really ride transit.  And few people like the idea of a vertical Beverly Hills going up in their neighborhood.

I don’t argue with these conclusions, but I think we need to be mindful of a few things.  First, we don’t want to segregate low and moderate-income people around transit nodes in homogenous communities.  For healthy, functional communities, we need people and families with a mix of incomes in close proximity.

Second, all this affordable housing comes with significant public subsidy, so we need to be honest about how we’re going to pay for it.  More developer fees?  Fees on real estate documents?  Bonds?  There are potentially less-expensive options to help make housing affordable, like boosting the supply at all income levels in our cities (which helps solve many other challenges, such as economic inequality and sprawl).

But a third thing to keep in mind is that rich people are huge resource hogs, and helping them live in infill, urban areas offers numerous environmental benefits.  As my UC Berkeley colleagues documented last year, suburban sprawl is terrible for carbon emissions, compared to urban development.

But it’s not just about carbon.  Case in point: in the Bay Area’s East Bay, the water utility just released a list of the biggest water guzzlers who have been fined for their excess. And guess where the top water-wasters are?  Out in the suburbs, not in the cities:

The top water user, amid a fourth year of extreme drought that has caused farmers to fallow fields and wells to go dry, was Kumarakulasingan “Suri” Suriyakumar, president and chief executive of ARC Document Solutions, a Walnut Creek software company that caters to the construction industry. Records show he consumed 9,612 gallons a day at his eight-bedroom, nine-bathroom, 11,368-square-foot Diablo compound next to Mount Diablo State Park.

Here’s the map from the San Francisco Chronicle to put it into perspective, and note the lack of water-wasters in the urban areas along the bay shore, from Richmond to Oakland:

And that’s just water. Electricity data are private (water, too, unless you get fined for a violation), but you can bet these people’s electricity and natural gas usage is off the charts, too. Not to mention their consumption of goods to supply their large homes, from furniture to other equipment.

So all in all, while we want to encourage more affordable housing in our cities, we definitely want to encourage rich people to live in them, too.  It sure beats the water-guzzling, resource-hogging, sprawl-inducing alternative.