California Dominates Urban Area Density Rankings


The newly released Census Bureau urban area reveals all 10 or the densest urban areas are in California, as well as 39 of the densest 50, and 70 of the 100. This is an unusually large concentration for a single state. An overall summary of the 2020 US urban areas was recently published in 2020 Urban Areas and Data Announced.

This article focuses on the 15 densest urban areas in the United States, according to the 2020 Census. New urban area criteria were adopted for 2020, which renders direct comparisons to previous data from the 1950 through 2010 censuses non-comparable.Chances are that they are unfamiliar to most, with the exception of San Francisco (San Francisco-Oakland)), Los Angeles (Los Angeles-Long Beach-Anaheim) and San Jose. These three urban areas are the only ones with more than 100,000 population among the top 15 densest areas.

The 15 Densest Urban Areas

Here’s a surprise, even for those of us closely involved in urban demography. Many of the densest urban areas in the country are located in primarily agricultural areas in California’s interior.

The Mecca, California is the densest urban area. Located just to the north of the Salton Sea, in Riverside County, it is nearly 40 miles east of Palm Springs and 140 miles east of Los Angeles, near the junction of California highways 86 and 111. Covering 0.6 square miles, Mecca has about 6,900 residents and a population density of 10,979 — more than 40% denser than either San Francisco or Los Angeles. Mecca is 70% denser than San Jose, 90% denser than the New York urban area and 170% denser than 89th ranked Portland (Oregon), despite its now nearly half-century of densification policy (urban containment policy). Mecca does not include an incorporated municipality.

The Greenfield, California urban area is second densest and is located in Monterey County, about 30 miles south of Salinas on US-101 and 150 miles south of San Francisco (more than one-third the way to Los Angeles). Greenfield has a population of 18,900 in 2.1 square miles, with a population density of 8,821 per square mile.

The Arvin, California urban area is third densest and located in Kern County, about 20 miles from Bakersfield and 100 miles from Los Angeles, to the west of the Interstate 5 corridor. Arvin has a population of 19,600 in 2.4 square miles, for a population density of 8,266.

The Parlier, California urban area is fourth densest and located in Fresno County, about 25 miles south of Fresno and 210 miles north of Los Angeles. It is located to the east of California highway 99, which is the principal route through the center of the San Joaquin Valley. The urban area has a population of 14,500 in 1.8 square miles, for a population density of 8,124 per square mile.

The Soledad, California urban area is fifth densest and located in Monterey County, between Salinas and second ranked Greenfield, about 20 miles south of Salinas and 140 miles south of San Francisco. With a population of 19,800 and a land area of 2.4 square miles, Soledad’s population density is 7,832 per square mile.

The 2020 San Francisco urban area is the 6th densest. It has a population of 3.3 million, covering a land area of 429 square miles (the 48th largest urban footprint in the nation). Its population per square mile is 7,626.

The 2020 Los Angeles urban area is the 8th densest, with 12.3 million residents in 1,637 square miles (the 8th largest urban footprint the nation), for a density of 7,476 per square mile.

Between the San Francisco and Los Angeles urban areas, the MacFarland urban area, Kern County, is the 7th densest. MacFarland is located on California highway 99, 25 miles north of Bakersfield and 135 miles north of Los Angeles. Its density is 7,599 per square mile.

The Calexico urban area is the ninth densest urban area and is located in Imperial County. Calexico has 38,000 residents in 5.4 square miles, with a density of 7,115. It is about 120 miles east of San Diego, and 85 miles south of the densest urban area, Mecca, south of the Salton Sea. Calexico is also directly across the border from Mexicali an urban area with a population of 958,000, and the capital of Mexico’s state of Baja California.

The 10th densest is the Guadeloupe urban area in Santa Barbara County, located about 10 miles from Santa Maria, with a population of 8,000, with a population density of 7,044.

The 11th and 12th densest urban areas are both in Arizona, located in Yuma County, in the southwestern corner of the state. The Somerton urban area has a population of 14,000 and a density of 6,836. The San Luis urban area is located virtually at the southwestern corner of the state, and has a population of 25,000 with a density of 6,710. Like Calexico, California (above), 50 miles to the west using Mexico federal highway 2, San Luis is directly across the border from a much larger urban area, San Luis Rio, Sonora (Mexico), which has about 200,000 residents.

The Wasco, California urban area is located in Kern County, between California highway 99 and Interstate 5. Wasco has 22,000 residents and a density of 6,449 per square mile. Wasco is 30 miles north of Bakersfield and 140 miles north of Los Angeles.

The San Jose urban area, almost exclusively suburban in urban form, is the 14th densest urban area in the nation. San Jose has a population of 1.8 million, in 285 square miles, with a population density of 6,436. San Jose is nearly 8% denser than the New York urban area (5,980 per square mile).

The Orosi urban area is the 15th densest and is in Tulare County. Like Mecca, this urban area does not include an incorporated general purpose government. Orosi’s 13,000 residents live in 2.0 square miles, at a density of 6,422.

Urban Density: From Los Angeles and New York to Mecca and Arvin

The urban area that most would expect to be at the top of the density ratings is New York (New York-Jersey City-Newark). And, indeed, New York City was the densest large municipality in the country. (28,000 per square mile). However, the population density in the balance of the urban area is far lower, at 3.200 per square mile. By comparison, the Los Angeles urban area had a suburban density about double that of New York, at 6,400. The San Francisco urban area suburbs has a density of 4,900 and the San Jose urban area suburbs are at 4,700. The large comparatively more dense suburban expanses of these three urban areas explains their higher overall densities compared to the New York urban area.

Density, it turns out, does not simply occur in places like New York or Los Angeles. In many cases, it shows up in the smallest urban areas.

Wendell Cox is principal of Demographia, an international public policy firm located in the St. Louis metropolitan area. He is a founding senior fellow at the Urban Reform Institute, Houston, a Senior Fellow with the Frontier Centre for Public Policy in Winnipeg and a member of the Advisory Board of the Center for Demographics and Policy at Chapman University in Orange, California. He has served as a visiting professor at the Conservatoire National des Arts et Metiers in Paris. His principal interests are economics, poverty alleviation, demographics, urban policy and transport. He is co-author of the annual Demographia International Housing Affordability Survey and author of Demographia World Urban Areas.

Mayor Tom Bradley appointed him to three terms on the Los Angeles County Transportation Commission (1977-1985) and Speaker of the House Newt Gingrich appointed him to the Amtrak Reform Council, to complete the unexpired term of New Jersey Governor Christine Todd Whitman (1999-2002). He is author of War on the Dream: How Anti-Sprawl Policy Threatens the Quality of Life and Toward More Prosperous Cities: A Framing Essay on Urban Areas, Transport, Planning and the Dimensions of Sustainability.

Photo: Bakersfield, California, seat of Kern County, home of three of the densest urban areas in the United States in 2020 (by author).