This story was originally published by CalMatters. Sign up for their newsletters.
California’s population exploded during and immediately after World War II, from 6.9 million in 1940 to 19.9 million in 1970, thanks to waves of migrants from other states drawn to California’s surging economy and the famous postwar baby boom.
California absorbed its 13 million new residents by expanding its public infrastructure of schools, colleges, highways, parks and water systems and by welcoming immense private investment in new housing, new retail complexes, new factories and new office buildings.
Population growth slowed in the 1970s in the aftermath of the baby boom and as an economic evolution, from manufacturing to technology and services, changed the job market. The leading politician of the decade, Gov. Jerry Brown, declared that California had entered “an era of limits” and major infrastructure expansion was no longer needed.
However, the 1980s saw a new population surge, driven by immigration from other countries and a new baby boom. California’s population jumped by 6 million — 5-plus million of them babies — during the decade, a more than 25% gain.
The increase was so large, relative to the nation as a whole, that California was awarded seven new congressional seats after the 1990 census.
Unlike California’s expansive reaction to its postwar population increase, the 1980s boomlet sparked an adverse reaction in the 1990s, including new laws aimed at denying public services to undocumented immigrants and a power struggle within the Sierra Club over immigration’s impact on the environment.
Meanwhile, population growth slowed again, and in this decade virtually halted as immigration and birth rates declined and substantial numbers of people left California, thanks largely to the state’s sky-high living costs.
A recent study by researchers Hans Johnson, Julien LaFortune and Eric McGhee at the Public Policy Institute of California found that the total fertility rate has dropped from 2.21 children per woman in 2007 to 1.48 in 2023, far below what demographers call the “replacement level of 2.1 necessary to keep a population from declining.”
The state lost a congressional seat after the 2020 census and is likely to lose several more after the 2030 census. However, the impacts of California’s population plateau extend far beyond politics.
“A smaller population can offer benefits; it reduces pressure on housing and infrastructure needs,” the researchers wrote, “easing congestion and reducing the need for expansive public works projects.” They also cited potential improvements in the environment and increasing per pupil spending on education as enrollment declines.
“At the same time,” they added, “fewer births — and a smaller population — may bring challenges: they could accelerate K–12 enrollment declines and strain the state’s economic and safety net systems as fewer workers support a larger share of older Californians. Labor shortages could also hinder California’s economic development.”
Those are all valid points and many more potential impacts could be mentioned. But the underlying issue is whether political policies will reflect the new demographic reality.
The post-World War II population explosion manifested itself in a bipartisan effort to do what was needed to make the transition relatively painless. We haven’t seen such political adjustment to changing demographic trends since.
Meanwhile, the state’s population is twice what it was in 1970 and we still depend on what politicians wrought in the post-war era — such things as the State Water Plan and our extensive freeway network.
A stagnant population eases pressure for new infrastructure but we still need to maintain what we have and expand it to meet current needs. However, water projects have languished and we no longer build new highways.
Jerry Brown, who proclaimed the “era of limits” in the 1970s, returned to the governorship in 2011 and declared, “I want to get shit done.”
There’s still much that should be done.



