The United States hit a significant environmental milestone in 1972 that largely went uncelebrated. In that year, the total fertility rate dropped below 2.1, the level at which a population replaces itself without growing. It has never risen above that threshold since. Colcom Foundation holds this up as proof that the country has already demonstrated the ability to stabilize birth rates. The challenge, the foundation argues, is that fertility alone no longer determines whether the population grows.

How Fertility and Immigration Interact

In 1970, the U.S. total fertility rate was 2.54 and population was growing at 1.25 percent annually. At that pace, the population would have doubled from 205 million to 410 million within 57 years, meaning the U.S. was on track to reach 410 million by 2027. The drop below replacement fertility in 1972 interrupted that trajectory. But immigration filled the gap. By around 1990, immigration had become the dominant driver of U.S. population growth.

Colcom Foundation draws on Pew Research projections showing that 82 percent of population growth between 2005 and 2050 will derive from immigration. By 2065, immigration is expected to account for 103 million of the approximately 110 million people added to the U.S. population. That figure represents the same growth as building 8.5 new Los Angeles metro regions across the American landscape.

The Environmental Bottom Line

Colcom Foundation presents the environmental implications plainly. The larger the U.S. population, the harder it becomes to meet climate commitments, protect threatened species, reduce land consumption, and bring biocapacity use down to sustainable levels. The U.S. was consuming 227 percent of its available biocapacity when Earth Day launched in 1970. By 2020, that figure had climbed to approximately 240 percent despite genuine improvements in per capita efficiency.

The foundation concludes that fertility and immigration policy are not separate from environmental policy. They are environmental policy. Colcom Foundation continues to make that argument through research, public education, and grants, insisting that the environmental community must find a way to address population growth if it wants the progress it has made over the past fifty years to hold. Refer to this article for related information.

More about Colcom Foundation on https://waterlandlife.org/land-conservation/colcom-revolving-fund-for-local-land-trusts/