Projecting Indian Populations for the Purpose of Determining Water Requirements: Methodological Issues

Gretchen Greene, Northwest Economic Associates
Michael Taylor, Northwest Economic Associates
Jeri Sawyer, Northwest Economic Associates

Objectives This paper will review the various demographic issues that influence long-run population forecasts for Indians living on reservations. Using the cohort component method, topics include a review of the strengths and weaknesses of various sources of data, the increasing incidence of Indian self - identification, correcting for census undercounting, a review of approaches to each of the components of change, and the use of uncertainty parameters within the cohort component method. Background In the 1800s, many American Indian tribes entered into treaties with the United States through which the preservation of rights was exchanged for a reservation as a homeland. Since that time the Supreme Court has affirmed that the United States maintains a trust responsibility for the protection of tribes and tribal resources. Determining the bounds of this protection is an important requirement for assuring that the federal responsibility is met. The resource base of the reservation homeland provides the foundation for many rights and protections. This is particularly true in the case of water rights for agricultural irrigation purposes. But securing and protecting rights to water for other purposes of the reservation, such as domestic, commercial, municipal, or industrial uses, is not as well defined. However, it is likely that the quantification of those rights will be based upon the population that is to be served by those rights. Yet an accurate count of the current population of American Indians living on reservations has become somewhat elusive for a variety of statistical, methodological, and cultural reasons. This can lead to a serious misrepresentation, and usually underestimate, of the level of tribal rights and the extent of trust responsibility to be provided by the United States to many tribes. Furthermore, this has serious implications when entitlement resources such as health care and educational funding are based upon the quantity of the service population. After the 1990 U.S. Census, in which the Census Bureau estimated that Indians living on reservations were undercounted by 12.2 percent, much concern was raised within Indian Country about census participation. Adjusted counts were produced for Indian populations on reservations, though the U.S. Congress never officially accepted these counts. Later, in 1995, a workshop was held by the National Research Council’s Committee on Population to examine the effects of an Indian population that was changing not only by the traditional components of change (birth, death, and migration), but also by the increasing incidence of Indian self-identification. The papers from the workshop were published in one volume in 1996 that identified many of the issues. Since that time, little has been written about changing demographics of Indians on reservations, although there is a great need to provide information to both Tribes and the federal government on this topic. Methodology Literature and data from various demographic and Native American sources will be reviewed with the goal of conducting a population projection using the cohort component method. Based on this review, a set of assumptions will be developed for a long-run (100-year) projection of one reservation. Assumptions will be developed regarding 1) An appropriate method for adjusting baseline census data for undercounting, 2) changing patterns of Indian self-identification, including an approach to tabulation of multiracial Indians from the 2000 census, and 3) the use of uncertainty parameters within the projection. A sensitivity analysis will be conducted comparing projection results under modifications of the assumptions developed above. Expected Results The results of this review will be two-fold. First, the review should provide an update of some of the issues raised at the conference held in 1995 by the National Research Council. Second, the results should demonstrate the impacts of the assumptions under consideration, and therefore the relative importance of the different assumptions. Discussion This topic should generate some discussions about the importance of demographic data for indigenous peoples in North America. Although many of these groups enjoy a geographically well-defined home, the demographic issues of identity are less well defined. Still, these issues play a potentially important legal role that is critical to ability of native people to exercise their rights, and more research on these topics is recommended.