Sometime this month, the U.S. population is projected to reach 300 million. In times past, reaching such a demographic milestone might have been a cause for celebration. In 2006, it is not. Population growth is the ever expanding denominator that gives each person a shrinking share of the resource pie. It contributes to water shortages, cropland conversion to non-farm uses, traffic congestion, more garbage, overfishing, crowding in national parks, a growing dependence on imported oil, and other conditions that diminish the quality of our daily lives.

With births exceeding deaths by nearly two to one, the U.S. population grows by almost 1.8 million each year, or 0.6 percent. Adding nearly 1 million immigrants per year brings the annual growth rate up to 0.9 percent, raising the total addition to 2.7 million. As things now stand, we are headed for 400 million Americans by 2043. (See data.)            

U.S. population growth contrasts with the situation in other industrial countries such as France, the United Kingdom, Germany, Italy, and Japan, where populations are either essentially stable or declining slightly. In virtually every industrial society where women are well educated and have ready access to jobs, they have on average two children or fewer.

More people require more of everything, including water. In our highly urbanized society, we fail to recognize how much water one person uses. While we drink close to a gallon of water each day as water, juice, pop, coffee, tea, beer, or wine, it takes some 500 gallons a day to produce the food we consume.

The U.S. annual population growth of nearly 3 million contributes to the water shortages that are plaguing the western half of the country and many areas in the East as well. Water tables are now falling throughout most of the Great Plains and in the U.S. Southwest. Lakes are disappearing and rivers are running dry. It has been years since the Colorado River, the largest river in the U.S. Southwest, reached the Gulf of Mexico.

As water supplies tighten, the competition between farmers and cities intensifies. In this contest, farmers almost always lose. Scarcely a day goes by in the western United States without another farmer or an entire irrigation district selling their water rights to cities like Denver, Las Vegas, Phoenix, Los Angeles, or San Diego.

The seafood appetite of 300 million Americans is also outgrowing the sustainable yield of its coastal fisheries. Long-time seafood staples such as cod off the New England coast, red snapper in the Gulf of Mexico, and salmon in the U.S. Northwest are threatened by overfishing.

In the United States, more people means more cars. And that in turn means paving more land for roads and parking lots. Each U.S. car requires nearly one fifth of an acre of paved land for roads and parking space. For every five cars added to the U.S. fleet, an area the size of a football field is covered with asphalt.

More often than not, this land being paved is cropland simply because the flat, well-drained soils that are good for farming are also ideal for building roads and parking lots. Once paved, land is not easily reclaimed. As environmentalist Rupert Cutler once noted, “Asphalt is the land’s last crop.”

The United States, with its 226 million motor vehicles, has paved some 4 million miles of roads—enough to circle the Earth at the equator 157 times. In addition to roads, cars require parking space. Imagine a parking lot for 226 million cars and trucks. If that is too difficult, try visualizing a parking lot for 1,000 cars and then imagine what 226,000 of these would look like. (See Paving the Planet.)

More cars also translates into more traffic congestion. Americans are spending more and more time sitting in their cars going nowhere as freeways and streets become, in effect, parking lots. As cities sprawl, commuter distance lengthens.

Longer commuting distances and more congestion en route combine to increase the time spent in automobiles. In 1982 the average motorist experienced 16 hours of delay; by 2003 this had virtually tripled to 47 hours. Car commuting time is increasing in nearly every U.S. metropolitan area. “Rush hour” everywhere is becoming longer as commuters attempt to beat it by leaving work early or delaying their commute until traffic eventually wanes.

The costs of increasing congestion and longer commuting times are high. Traffic congestion in the United States in 2003 caused 3.7 billion hours of travel delay and wasted 2.3 billion gallons of fuel. The total bill for all of this was $63 billion.

Some corporations have begun to consider congestion costs when deciding where to establish a new plant or office building. They are concerned about both the effects of traffic congestion on their employees and the costs for the company itself when the movement of raw materials and finished products is slowed.

More people mean that not only are our home towns more crowded, but so too are the “get away” spots where we go for relaxation. National parks, wilderness areas, and beaches are seeing more visitors each year. U.S. national parks sometimes have to turn tourists away. In 1906 when Yosemite National Park was young and when we were a far less mobile population, the park had 5,000 visitors. Today, more than 3 million people (and their cars) visit the park each year.

More people also usually means more garbage. New York City, for example, generates 12,000 tons of garbage a day, a flow that requires 600 tractor-trailers—fully loaded—to leave the city each day headed for remote landfills in New Jersey, Pennsylvania, Virginia, and Ohio. Trucking garbage to ever more distant landfills makes us more dependent on distant sources of oil.

As population grows, so does energy consumption. The United States, richly endowed with oil, has largely depleted its petroleum reserves within two generations. The use of oil has exceeded new discoveries in the United States for some 25 years. As reserves shrink, U.S. production falls and imports /css/er__almost_all_other_industrial_countries_now_have_stable_or_declining_populations._Perhaps_it_rsquo_mkzvepzjqhabjxtzzau747.css;s time for us to stabilize the U.S. population as well, so that we never have to ask whether 400 million Americans is a cause for celebration.

Copyright © 2006 Earth Policy Institute