Alternatives Selected for Study

A crucial aspect in conducting an adequate environmental impact statement is properly selecting the alternatives for detailed analysis and comparison.[1] Early in this investigation, we determined that the alternatives to be studied and compared in depth would be specified primarily in terms of the annual immigration levels set under each alternative.

Making immigration policy involves other choices besides the overall level of immigration. These include the percentage of immigrants allotted to various “sender” countries, the skill and education levels desired, when and whether to grant citizenship to new arrivals, the parameters of a fair and just refugee policy, and more. These are important questions. However, there is no evidence that how they are answered makes a significant difference regarding the ecological questions that are the focus of this study. For example, there is no evidence that where immigrants come from significantly decreases or increases their U.S. descendants’ energy or resource consumption levels.

Regarding environmental impacts, the key issue appears primarily to be one of numbers. Therefore, in the study to follow, the questions that we will be focusing on are: How will annual immigrant numbers influence total population numbers now and in the future? How are different future population numbers likely to affect a full spectrum of ecological impacts (including water withdrawals, sprawl development, greenhouse gas emissions, and loss of threatened and endangered species)?

For similar reasons, vexing questions regarding how to manage illegal immigration are not directly addressed in this study. For the purposes of the alternatives considered, legal and illegal immigrants are treated equally, with the analytic focus on total annual immigration, to which both legal and illegal immigration contribute. From both a demographic and ecological perspective it makes little difference whether immigrants are in the country legally or illegally, particularly since the children of illegal immigrants born in the U.S. are granted automatic U.S. citizenship.

Of course, choices regarding how to manage illegal immigration may have important demographic consequences. Illegal immigration probably accounted for between one-fifth to one-third of total immigration into the U.S. during the past three decades. [2]  Nevertheless, the alternatives in this study will be specified in terms of total annual immigration, with no consideration given to the percentages of legal and illegal immigration that might make up that total.

“No Action” Alternative

According to the National Environmental Protection Act (NEPA), every federal EIS must include a “no action” alternative in its detailed analysis. This is to ensure that the well-known managerial bias in favor of “doing something” does not lead to inadvisable actions, when doing nothing (or continuing to do whatever we are currently doing) would actually be preferable. For this EIS, we define the “no action” alternative as a continuation of status quo immigration policies.

According to the Office of Immigration Statistics, in recent years legal immigration into the United States has averaged around 1.1 million people annually.[3] However, half a century of relative tolerance for illegal immigration (shown in widespread condemnation of enforcement efforts, periodic amnesties and grants of citizenship to illegal immigrants, and the continuation of “birthright citizenship” long after many nations around the world have discontinued it) suggests that illegal immigration’s contribution to total immigration numbers should be treated as part of the political “status quo.”

Illegal immigration is difficult to quantify. Having soared to perhaps half a million annually by the late 1990s, it dropped sharply after the 2007 recession, to perhaps a few hundred thousand net.[4] Estimating conservatively that illegal immigration has averaged 150,000 people annually over the past five decades, we add 150,000 to our baseline of 1.1 million annual legal immigrants. This sets the “no action” alternative at 1.25 million annual immigration.

Alternatives Rejected for Detailed Study

 In soliciting public input on this EIS on U.S. immigration policy, we fielded a wide range of suggestions regarding which other alternatives to include. Many comments suggested “zero immigration” or “zero net migration” as alternatives. These options were sometimes proposed as the environmentally optimal alternatives. Sometimes they were proposed because commenters felt that including zero or zero net immigration options would make immigration-driven population growth’s contribution to Americans’ total ecological impact more clear.

At the other end of the spectrum, several comments suggested that we analyze a true “open borders” alternative, allowing in any would-be immigrants without a criminal record. Given the huge pent-up demand for emigration from poor countries into the U.S., such a policy might initially bring in many millions of new immigrants annually. While some commenters proposed such an alternative as the morally right thing to do, others, who strongly disagreed with this moral judgment, nevertheless thought that widespread support for such an alternative meant that it deserved to be analyzed.

We rejected such very low and very high alternatives for detailed analysis in this EIS. This was not because each of them does not have significant numbers of advocates, or because they are strictly speaking impossible. Instead, we rejected them because they are unlikely to be considered seriously for adoption in the near future. Like any EIS, this one aspires to inform actual decisions: in this case, public policy decisions in the immigration realm. We thus worked to keep our detailed alternatives relevant to realistic policy decisions.

Similar practical considerations pointed to a need to limit the number of alternatives considered, both to keep researchers’ workloads manageable and in order to provide greater clarity for readers of the EIS. [5] We believe readers will be best served by a small number of alternatives that decrease or increase current immigration numbers, but that have a significant chance of being enacted. We therefore propose two such alternatives for detailed study (in addition to the “no action” alternative): a substantial reduction alternative and a substantial expansion alternative, described below.

Alternatives Selected for Detailed Study

The proposed reduction alternative sets annual net immigration at 250,000. This represents a substantial (80%) decrease from current numbers, but not an impossible one. Assuming conservatively 100,000 annual emigrants from the U.S., this alternative would allow 350,000 annual immigrants into the country (for a total of 250,000 net immigration). Based on recent figures, 350,000 would be enough to fulfill the United States’ moral responsibility to provide asylum for legitimate political refugees, to provide citizenship for foreign-born spouses and adopted children of American citizens, and to leave some spots open for immigrants with exceptional abilities to enter the United States on work-related visas.

While 250,000 net immigration is far below current immigration numbers, those numbers are the highest in U.S. history. 250,000 was approximately the annual immigration level for the four decades between 1925 and 1965, the “Great Pause” between the two “Great Waves” of mass immigration into the U.S.[6] It is actually a little higher than the average annual immigration over the entire history of the United States.[7] For these reasons, we take 250,000 annual immigration to be a reasonable alternative for analysis.

Our proposed expansion alternative sets annual net immigration at 2.25 million. This represents a substantial (80%) increase over current numbers, but again, not an impossible one. There exists considerable pent-up demand around the world for immigration into the United States; in recent years, the annual green card “diversity lottery” has garnered over 10 million applications to fill its 50,000 slots. Many millions of relatives of U.S. citizens and residents would welcome the opportunity to immigrate into the U.S.

2.25 million annual immigration also has salience in terms of recent policy proposals. Some analyses of the “Secure Borders, Economic Opportunity and Immigration Reform Act of 2007” (S. 1348), co-sponsored by Senators Kennedy and McCain, asserted that it would have pushed annual immigration above two million. While a full proposal or definite numbers are not yet available, recent “comprehensive immigration reform” proposals by the Obama administration and the bipartisan “Gang of Eight” in the U.S. Senate, both advocate substantial increases over current immigration numbers (through legalizing illegal immigrants, greatly increased worker visa numbers, new “guest worker” programs, expedited “family reunification” programs, and additional means). While 2.25 million may be too high a number for what these proposals seek to legislate, it could just as easily be too low. We thus take 2.25 annual immigration into the U.S. to be a reasonable alternative for analysis.

Our three main alternatives for detailed analysis in this EIS are therefore the following: 250,000 annual immigration into the U.S. (the reduction alternative), 1.25 million annual immigration into the U.S. (the “no action” alternative), and 2.25 million annual immigration into the U.S. (the expansion alternative). Readers interested in considering the environmental impacts of more limited reductions or expansions in immigration numbers, should be able to better understand the ecological implications of these further alternatives, by comparing them to the alternatives chosen for detailed analysis in this study.

Population Projections to 2100

We have calculated initial population projections for our three selected alternatives using the cohort-component method, the standard method used by demographers for national population projections.[8] In the cohort-component method, one starts with a certain size population with a particular age-structure (this was determined, in our projections, by the 2010 U.S. Census). Then one takes that population forward in time as it responds to four key factors: births (fertility), deaths (mortality), immigration, and emigration. These last two factors are sometimes combined as “migration” or “net migration.”

As described in our earlier report on U.S. demographic projections, we utilize a projection tool developed by Decision Demographics, Inc. and the Center for Immigration studies. As noted, these researchers replicated the model created by the U.S. Census Bureau for its 2008 and 2009 population projections.[9] The resultant projection tool allows users to vary fertility levels and immigration levels; hence, it can take into account the Census Bureau’s revised 2012 projections. Use of the D.D./C.I.S. projection tool allows us to ground our projections in the best available demographic data.

In creating the population projections for this study, we held fertility and mortality rates steady under all three alternatives, at the levels predicted by the U.S. Census Bureau in its 2008 projections. The rationales for these particular fertility and mortality rates may be found in the methodology statement for the Census Bureau’s 2008 projections (which should be compared to that for the Bureau’s 2012 projections).[10] Then we phased in the proposed changes from current net immigration levels over six years, starting in 2014 and ending in 2020. After 2020, we held annual immigration levels steady at 250,000, 1.25 million and 2.25 million, respectively, out to 2100. This method generated the following population projections under our three alternatives:

Average annual net immigration

Population in 2010 Population in 2050

Population in 2100

250,000 309 million 369 million 379 million
1.25 million 309 million 415 million 524 million
2.25 million 309 million 460 million 669 million

In graphic form, our population projections to 2100, under the three alternatives selected for analysis, appear as follows:

U.S. Population Projections to 2100 under Three Scenarios

As can readily be seen, the population projections under our three alternatives point to three very different demographic futures for the United States. Most obviously, population grows by 70 million people over the course of the 21st century under the reduced immigration alternative, by 215 million people during this same period under the “no action” alternative, and by 360 million people under the expansive immigration alternative.[11] This corresponds to a 23% population increase, a 70% population increase and a 117% population increase, respectively. Perhaps just as important, while population stabilizes toward the end of the century under the reduced immigration alternative, under both the status quo, “no action” alternative and the expansive alternative, America’s population trajectory in 2100 would likely ensure continued, substantial population growth far into the 22nd century.[12]

Comparing ecological impacts under these three demographic alternatives will be the researchers’ main goal, as we continue work on this EIS on U.S. Immigration Policy. As previously described, our comparative analysis will focus on six key areas:

•       urban sprawl and farmland loss

•       water demands and withdrawals from natural systems

•       greenhouse gas emissions and resultant climate change

•       habitat loss and impacts on biodiversity

•       energy demands and national security implications

•       and the international ecological impacts of U.S. immigration policies.

As always, we welcome your comments regarding our published findings, and your ideas for the best way forward as we continue to develop the EIS on U.S. immigration policy.

Population Projections to 2200

This EIS will analyze the potential ecological impacts of the three selected alternatives out to 2100. Focusing narrowly on impacts over a few decades, while perhaps appropriate for EIS’s that analyze individual or relatively small-scale projects, seems too short-sighted to provide a useful analysis of national population policy. On the other hand, considering ecological impacts beyond 2100 has been judged too speculative. Nevertheless, we may assume that whether the U.S. population is closer to a quarter billion people or a billion people over the course of the 22nd century might make a significant difference to the environmental future of the United States and the world as a whole.

For readers interested in the longer-term demographic implications of the three alternatives under study, we provide the following speculative population projections out to 2200. These near-200-year projections were made by piggybacking onto the 90-year population projections for the three main alternatives:

Three Alternatives Population in 2010 Population in 2100

Reduced immigration alternative (250,000 annual immigration)

309 million 379 million

No action alternative (1.25 million annual immigration)

309 million 524 million

Expansive immigration alternative (2.25 million annual immigration)

309 million 669 million

Next we calculated the percentage rate of population growth for the decade 2090-2100, under each of the three alternatives:

Three Alternatives

Percentage population change, 2090-2100

Reduced immigration alternative (250,000 annual immigration) + 0.2%
No action alternative (1.25 million annual immigration) + 4.2%
Expansive immigration alternative (2.25 million annual immigration) +6.6%

Finally, we took the rate of growth from 2090 to 2100 under each alternative, and projected that out for another hundred years, applying it to the given populations under each alternative. This led to the following population projections to 2200:

Three Alternatives Population in 2010 Population in 2100 Population in 2200
Reduced immigration alternative (250,000 annual immigration) 309 million 379 million 386 million
No action alternative (1.25 million annual immigration) 309 million 524 million 801 million
Expansive immigration alternative (2.25 million annual immigration) 309 million 669 million 1.298 billion

In graphic form, our population projections to 2200 under the three alternatives selected for analysis appear as follows:

U.S. Population Projections to 2200 under Three Different Immigration Scenarios

We find it noteworthy that while the immigration reduction alternative leads to an essentially stable U.S. population below 400 million people, both the “no action” alternative and the immigration expansion alternative lead to immense population increases, on the order of hundreds of millions more Americans. The latter alternatives also lock in continued upward population trajectories.

Under the immigration reduction alternative, the U.S. population grows by 77 million people between 2010 and 2200, for a 25% population increase over the entire period. Under the “no action,” status quo alternative, the U.S. population grows by 492 million people between 2010 and 2200, for a 159% population increase. Finally, under the expansive immigration alternative, the U.S. population grows by 989 million people during this same period, for a 320% U.S. population increase.

Once again, these population projections out to 2200 are quite speculative. Nevertheless, they do allow those of us concerned about ecological sustainability, to peer the recommended “seven generations” into the future and consider the implications for our descendants of the path that we are on.

Readers who find the idea of 800 million or more Americans preposterous might ask what, exactly, is going to change, to keep the United States from reaching such an immense population. One hundred years ago, the idea of a billion people living in China or India might have seemed preposterous to the average Chinese or Indian person. Today the populations of China and India both stand above one billion, with India set to reach one and a half billion within the next thirty years.[13]

[1] See questions 1-3 in Council on Environmental Quality, “Forty Most Asked Questions Concerning CEQ’s National Environmental Policy Act Regulations,” 46 Fed. Reg. 18026 (March 23, 1981), as amended by 51 Fed. Reg. 15618 (April 25, 1986), in Nicholas Yost, NEPA Deskbook, 2nd ed. (Washington, DC: Environmental Law Institute, 1995), pp.263-264. Also useful for understanding the decision-making process for selecting alternatives for analysis is Charles Eccleston, The NEPA Planning Process: A Comprehensive Guide with Emphasis on Efficiency (New York: John Wiley and Sons, 1999), pp.270-279.

[2] Ed Lytwak, “A Tale of Two Futures: Changing Shares of U.S. Population Growth” (Washington, DC: Negative Population Growth, 1999); Steven Camarota, “A Record-Setting Decade of Immigration: 2000-2010” (Washington, DC: Center for Immigration Studies, 2011); Pew Hispanic Center, “A Nation of Immigrants: a Portrait of the 40 Million, Including 11 Million Unauthorized” (Washington, DC: Pew Hispanic Center, January, 2013).

[3] Office of Immigration Statistics, “Annual Flow Report, U.S. Legal Permanent Residents: 2011” (Washington, DC: Department of Homeland Security, 2012), table 2.

[4] Pew Hispanic Center, “A Nation of Immigrants,” op. cit; Jeffrey Passel, D’Vera Cohn and Ana Gonzalez-Barrera, “Net Migration from Mexico Falls to Zero—and Perhaps Less” (Washington, DC: Pew Hispanic Center, May, 2012).

[5] See Eccleston, The NEPA Planning Process, loc.cit.

[6] Annual and decadal immigration numbers may be found in US Department of Homeland Security, "Yearbook of Immigration Statistics: 2011," table 1, “Persons Obtaining Legal Permanent Resident Status: Fiscal Years 1820 to 2011.” Accessible on the Department of Homeland Security website:

[7] Otis Graham, Unguarded Gates: A History of America’s Immigration Crisis (Lanham, MD: Rowman and Littlefield, 2004).

[8] See Brian C. O'Neill, Deborah Balk, Melanie Brickman and Markos Ezra. 2001. “A Guide to Global Population Projections.” Demographic Research volume 4, article 8, pp.203-288, for a lucid description of the cohort-component method.

[9] Steven Camarota, “Projecting Immigration’s Impact on the Size and Age Structure of the 21st Century American Population ” (Washington, DC: Center for Immigration Studies, 2012); Stephen Tordella, Steven Camarota, Tom Godfrey and Nancy Rosene, “Evaluating the Role of Immigration in U.S. Population Projections” (unpublished essay).

[10] See U.S. Census Bureau, “2008 National Population Projections: Methodology and Assumptions,” accessed at:; and U.S. Census Bureau, “Methodology and Assumptions for the 2012 National Projections” (Washington, DC: December 2012), p.11, accessed at:

[11] This confirms the findings in Jeffrey Passel and D’Vera Cohn, U.S. Population Projections: 2005-2050 (Washington, DC: Pew Research Center, 2008), that under a continuation of status quo immigration policies, post-2005 immigration will account for 82% of U.S. population increase between 2005-2050.

[12] Steven Camarota, “Projecting Immigration’s Impact on the Size and Age Structure of the 21st Century American Population” (Washington, DC: Center for Immigration Studies, December 2012) makes a similar point in evaluating population projections through the middle of this century.

[13] U.S. Census Bureau, “International Data Base,” accessed March 22, 2013 at: