A Drastic Proposal to Accommodate Mass Immigration into California

Californians have a long, proud history of environmental protection. But that heritage is threatened by continued population growth. Exhibit A is water policy, where Governor Gavin Newsom — supposedly strongly pro-environment — is trying to fast-track a water grab that will devastate the Sacramento River Delta, all to accommodate high levels of immigration.

California is America’s most populous state, and its population is concentrated within its southern half — the most arid part — where nearly two-thirds of the state’s 40 million inhabitants live. The region is chronically short of water, a shortage grown worse during the ongoing 25-year megadrought in the southwestern United States.

In May 2025, Governor Newsom urged state lawmakers to fast-track the approval of a massive water diversion effort — the proposed Delta Conveyance Project. Newsom called the $20 to $60 billion, 45-mile tunnel project the “key to the state’s climate adaptation,” especially in light of an anticipated 10% water-supply shortfall by 2040. The project would take water out of the Sacramento River to increase water delivery to Southern California and the Central Valley.

Environmental Concerns

The Delta Tunnel would divert vast quantities of fresh water from the San Francisco Bay-Delta estuary to industrial agricultural operations, as well as to the large cities of southern California. For those who push mass immigration and perpetual growth, the proposed Conveyance Project is the best way to keep the spigots open and the water flowing.

On the other hand, Sacramento River water levels are already at historic lows. Increased diversions could cause the ecological collapse of the largest estuary on the West Coast of the Americas. That’s why the Sierra Club and county governments in the Delta have sued to stop the project.

Over the course of many decades, California has constructed one of the world’s largest and most environmentally destructive system of dams, canals, and diversions. The result has been the closure of most of the state’s salmon fisheries and toxic algal blooms in San Francisco Bay. Both fish (e.g., Delta Smelt, Longfin Smelt) and wildlife species (e.g., Western Snowy Plover, San Joaquin kit fox) are at risk of extinction in the Bay Delta and the Central Valley.

Still, California’s political and business leaders refuse to accept limits to human demands on water and other natural resources. Despite calling himself a progressive environmentalist, Newsom’s administration is embracing a project that will increase already unsustainable levels of water diversion without addressing the underlying problem.

Alternative Solutions

California could consider more affordable water supply solutions, including wastewater recycling, stormwater capture, groundwater clean-up, and smart demand management.

Ultimately though, a sustainable response to California’s water woes involves curbing demand by ending population growth — and that includes reducing immigration, the main driver of that growth. The state must accept limits and acknowledge its human carrying capacity.

Since the first Earth Day in 1970, California’s politicians have acted as if they could have both environmental protection and endless population growth. They can’t. It’s time to face that reality.

The Elephant in the Room

The need for the Delta Conveyance project is being ascribed to climate change. It seems more accurate to cite population growth exceeding the carrying capacity of an arid ecoregion. Since 1960, California’s population has growth from 15 million to 40 million.

With fertility rates well below replacement level, America’s continued population growth is being driven by mass immigration. This is especially true for California, where 21% of U.S. foreign-born residents live. California has by far the highest number of immigrants of any state: 11 million (28% of the state’s population).

The proposed Delta Conveyance project is designed to service 5.2 million people, less than half of California’s immigrant population. If immigration levels had been lower in recent decades, the project would not be necessary.

California’s government is poised to embark on a misguided effort to accommodate continued immigration-driven population growth. Rather than keep feeding the growth machine, California politicians should come to terms with the area’s carrying capacity and accept immigration reduction as a key water conservation measure.

Immigration Reduction Strategies

During this Congress, NumbersUSA is promoting immigration policies to humanely reduce immigration, our Six Great Solutions. One solution tempers excessive legal immigration — the Nuclear Family Priority Act (H.R.2705 / S.1328) which limits family-sponsored immigration to immediate family members. One of the most effective ways to discourage illegal immigration is by mandating use of E-Verify for all new hires. The corresponding bills in Congress now are the Accountability Through Electronic Verification Act (S. 1151) and the Legal Workforce Act (H.R. 251).

NumbersUSA encourages you to contact your Congressional Representatives and Senators to support these bills. They will help protect California’s Sacramento Delta Estuary and other fragile ecosystems across America.