As Derek Thompson put it in March, Americans love big, hot suburbs—at least, that’s where latest Census numbers show the most population growth. Warm-weather counties in Texas, California, Arizona, and Florida had the biggest gains out of anywhere in the country, attracting Americans with their expanding job markets and relatively affordable housing stock.
But while weather may be part of the allure for recent arrivals, many of these fastest-growing counties are also experiencing drought conditions. As a recent Brookings Institution blog post pointed out, about 57 percent of the county’s total population growth since 2000 has occurred in counties with some degree of drought. Los Angeles, Riverside, and San Diego counties in California; Maricopa County in Arizona; and Miami-Dade in Florida all ranked high in population gains, and all are experiencing some of the driest conditions in the country.
Many agencies in these regions are doing what they can to conserve and recycle water, with mandated usage cuts, special rate structures, tax rebates, educational outreach, and new technologies. “These innovative steps represent crucial steps to address the country’s needed investment in water infrastructure,” writes Brookings. But water infrastructure isn’t the only kind of planning these bone-dry, booming counties badly need. As they grow, they’ve got to grow “smart,” with an emphasis on density. Among all kinds of other benefits, dense development will help mitigate water consumption. As I wrote in March,
Urban sprawl, intuitively, affects water consumption. Typically, low-density development (with the large lot sizes and more landscaping) results in higher total water use as well as higher per capita water use. And not only does sprawl contribute to traffic, air pollution, and lower health outcomes, it also threatens the quality and availability of water itself. A report from Smart Growth America writes, "As the impervious surfaces that characterize sprawling development—roads, parking lots, driveways, and roofs—replace meadows and forests, rain no longer can seep into the ground to replenish our aquifers."
If American’s big, hot counties are serious about planning for a water-scarce future, local planners would be wise to get smart.