“30×30” movements around the world are pressing national governments to ensure that 30 percent of their land masses are protected from development by 2030. The more-ambitious “Nature Needs Half” movement argues for stopping the destruction of natural habitat before the ratio falls below 50 percent (already too late for many countries).
This study examines the powerful counterforce of urban sprawl in the United States. The good news is that the rapacious rate of open space destruction of the 1980s and 1990s has slowed considerably. But urban sprawl continues to apply the chainsaw and bulldozer blades to vast amounts of rural land each year.
Between 2002 and 2017 (the period of the most recent government data), the federal Natural Resources Conservation Service identified around 17,800 square miles of new sprawl. (We use the term “sprawl” in the precise way of all our reports since 2000: “Sprawl” is the amount of rural land lost to development, regardless of its attractiveness or density.) That means 17,800 square miles of natural and agricultural land were converted during that period into developed land for residential, commercial, industrial, transportation, and other purposes.
Our study calculated that the cause of the 2002-2017 land loss fell into a surprisingly neat 2-to-1 ratio between the two overall factors of sprawl:
Figure ES-1. Square Miles Of National Land Loss Related To Population And To All Other Factors (2002-2017)
We also calculated rural land loss and its causes in each state (other than Alaska, which the government doesn’t include in its survey). On the map below, you can roll over any state to see the total square miles of habitat and farmland loss during the most recent 15-year period of data. You will also see a pie chart that will display the percentage of that rural land loss that is related to the state’s population growth and the percentage related to all other factors (which increase the amount of developed land per resident of the state). Twenty-six states experienced an overall decrease in developed land per resident during the recent period. That would suggest that zero percent of the land loss would be attributed to growth in per capita land consumption. However, our study found that per capita land consumption growth was a factor for at least some of the land loss in all those states because our calculations disaggregate each state’s data by county, and even states with no per capita consumption growth overall have at least some counties with growth in developed land per resident.
Figure ES-2. Land Loss In Each State And Percent Related To Each Sprawl Factor (2002-2017)
In the United States, nearly all government efforts to combat sprawl have focused on strategies which primarily seek to create denser settlement by changing land use practices.
Our findings, however, indicate that approach will have limited success in saving rural land from development because it fails to address the key reason for current sprawl – population growth and its overwhelming driver, federal immigration policies. Twenty-six states with declining development per resident in the 2002-2017 period provided case studies for that proposition.
The residents of those states lived, worked and shopped more densely than prior to 2002. How did that happen? Certainly, some role was played by so-called Smart Growth planning efforts, higher gasoline prices, fiscal and budgetary constraints (limiting new road-building, for example), the increasing popularity of denser city living (pre-Covid pandemic) and its cultural amenities, and the recession-inducing mortgage meltdown in 2008.
The extent to which any of those and still other unforeseen factors and events – such as the COVID-19 pandemic of 2020-2022 – may affect the rate of per capita sprawl in the coming decades is unknown and unpredictable. It may well be, for example, that concerns about high density residential living in the face of pandemics could increase sprawl pressures by raising the preference of consumers for lower-density suburban neighborhoods.
The 26 states with declining development per person are shown in Figure ES-3 with negative percentage numbers in green-shaded boxes. As you can see in the column next to them containing the square miles of lost rural land, all 26 states still sprawled over additional large areas of natural habitat and farmland. The population growth in these states simply erased any land-conservation benefit of denser living and better planning.