Just like rising energy demand, global warming, and racial distrust, America’s population boom is escaping serious attention from both presidential candidates. This is happening —or rather, not happening — even though the United States is growing more rapidly than it ever has before. By 2050, according to the U.S. Census Bureau, 420 million people will live here, 140 million more than in 2000. 

Is the country prepared for adding 50 percent more people in 50 years? Hardly. Just look at how America responded to the 33 million more people that joined us here in the 1990s: We paved millions of acres of open land, suffered from record levels of traffic congestion, overwhelmed sewage plans and polluted countless rivers and lakes with storm water runoff. We also widened the economic and social gulf between the outer suburban “haves” and just about everybody else.

If the country continues to spread out as it has, with developed acreage growing seven times faster than the population, roads and parking lots and buildings will cover 157 million acres. That’s about the size of Texas and nearly three times more land than is already developed today. In other words, if we do not change how we grow over the next 46 years, the United States will become an unrecognizable mess.

That is why the country must face up to its demographic future and install a new development policy that assures that America doesn’t choke on its growth. Robert Yaro, president of the Regional Plan Association in New York and one of the country’s most prominent planners, says the country has a long tradition of developing such national plans.

The first such growth plan arrived in 1807, following the Lewis and Clark expedition, when President Jefferson drew up a plan to incorporate the 863,072-square-mile Louisiana Purchase into the rest of the country. In December 1861, President Lincoln signed the Homestead Act to encourage westward settlement, and the Morrill Land Grant College Act, to provide for the development of higher education in “agriculture and the mechanic arts.” In 1906 and 1907, President Theodore Roosevelt signed a series of national park, forest, and game reserve laws that conserved 230 million acres of the country’s most beautiful wild lands. And in 1956, President Eisenhower signed the Federal-Aid Highway Act that authorized the construction of a 41,000-mile Interstate Highway system.

In effect, every half-century or so demographic and economic trends converge so significantly that they force the country to think in novel ways about where it’s heading. That moment has arrived once again.

Earlier this year, faculty and graduate students at the University of Pennsylvania analyzed the Census Bureau’s 50-year population projections and separate projections from Woods and Poole Economics, a Washington-based research firm. The group came to some portentous findings: They concluded that, by 2050, 307 million Americans, 71 percent of the population, will live in just 8 “supercity” regions that today have roughly 175 million people. In other words, most of the population increase will come in a handful of urban regions that will bleed across state boundaries like the Boston-to-Washington corridor does today.

California will have two supercities — one stretching from San Diego to north of Los Angeles and the southern Central Valley, the other encompassing the San Francisco Bay Area and Silicon Valley and reaching inland to Modesto and Sacramento.

A third supercity will permeate the Pacific Northwest, including Portland, Takoma, and Seattle. A fourth, in Texas, will encompass San Antonio, Austin, Dallas, Fort Worth, and Houston. Almost all of Florida will be a supercity. The South’s supercity will reach from Birmingham through Atlanta to Charlotte and Raleigh/Durham. The Midwest’s will start in Cleveland and include Detroit, Chicago, and Milwaukee. The East’s will reach from Richmond all the way up the Atlantic Coast to Portland, Maine.

Immigration will drive much of the growth, demographers say. The Hispanic population will almost triple, from 35.6 million to 102.6 million, or nearly 25 percent of the population. The Asian population will more than triple, from 10.7 million to 33.4 million, or 8 percent of the population. By contrast, the white population will grow by less than 7 percent, or 15 million people, bringing that group’s total to 210 million, or half the population.

As this multi-cultural future unfolds, America will face levels of sprawl, traffic, pollution, and competition for economic and natural resources that it simply has never seen before. As the South’s supercity triples the region’s population, the Bay Area’s population doubles, southern California’s grows by more than half, and the other megalopolises show similar dramatic gains, the need for new infrastructure will be immense. That is why using the same sprawling designs we use today simply will not work and why we must drastically change our patterns of development.

Take transportation: Highway construction alone will not come close to solving the gridlock that comes with putting 100 million more vehicles on the road. But a national network of high-speed rail lines linking airports to downtowns can ease traffic congestion and make America more mobile and energy efficient, and less polluting. So will a federal transportation policy that encourages building many more regional commuter rail systems, which both relieve traffic jams and foster more compact development around station stops. This will ease competition for open land and make it possible for families to get by with one instead of three or four expensive autos.

Achieving even these obvious, greatly needed changes in transportation policy seems a daunting challenge in this era of lower taxes and less public investment. But America is waking up to the realization that it simply cannot meet one of its chief challenges — fitting many more people on the land — with more tax and spending cuts. If anything, the country must do the opposite, and quickly, to avoid the much greater congestion, chaos, taxes, and spending that using the current approach will surely engender. Wise investments in planning, housing, transportation, and conservation will help ensure that 2050 America is both globally competitive and a good place to live. 

Keith Schneider is a journalist and deputy director of the Michigan Land Use Institute. Reach him at keith@mlui.org.