Identification and dating of indigenous water storage reservoirs along the Rio San Jos  e at Laguna Pueblo, western New Mexico, USA Gary Huckleberry a, * , T.J. Ferguson b , Tammy Rittenour c , Christopher Banet d , Shannon Mahan e a Department of Geosciences, University of Arizona,1040 E. 4th Street, Tucson, AZ 85721, USA b School of Anthropology, University of Arizona, P.O. Box 210030, Tucson, AZ 85721-0030, USA c Department of Geology, Utah State University, 4505 Old Main Hill, Logan, UT 84322-4505, USA d Southwest Regional Office, Bureau of Indian Affairs, 1001 Indian School Road NW, Albuquerque, NM 87104, USA e U.S. Geological Survey, Luminescence Laboratory, Denver Federal Center Box 25046 MS 974, 2nd and Center, Bldg.15, Denver, CO 80225-0046, USA article info Article history: Received 24 June 2015 Received in revised form 31 October 2015 Accepted 10 November 2015 Available online xxx Keywords: Laguna Pueblo Reservoirs Luminescence Stratigraphy abstract An investigation into indigenous water storage on the Rio San Jos e in western New Mexico was con- ducted in support of efforts by the Pueblo of Laguna to adjudicate their water rights. Here we focus on stratigraphy and geochronology of two Native American-constructed reservoirs. One reservoir located near the community of Casa Blanca was formed by a ~600 m (2000 feet) long stone masonry dam that impounded ~1.6  10 6 m 3 (~1300 acre-feet) of stored water. Four optically stimulated luminescence (OSL) ages obtained on reservoir deposits indicate that the dam was constructed prior to AD 1825. The other reservoir is located adjacent to Old Laguna Pueblo and contains only a small remnant of its former earthen dam. The depth and distribution of reservoir deposits and a photogrammetric analyses of relict shorelines indicate a storage capacity of ~6.5  10 6 m 3 (~5300 ac-ft). OSL ages from above and below the base of the reservoir indicate that the reservoir was constructed sometime after AD 1370 but before AD 1750. The results of our investigation are consistent with Laguna oral history and Spanish accounts demonstrating indigenous construction of significant water-storage reservoirs on the Rio San Jos e prior to the late nineteenth century. © 2015 Elsevier Ltd. All rights reserved. 1. Introduction Persistent drought and growing population are making it increasingly difficult to meet water needs in many parts of the globe. A prominent example is the North American Southwest (herein Southwest) where climate change and population growth raise concerns about environmental and economic sustainability (deBuys, 2011; MacDonald, 2010). Concurrent with these converging forces is conflict over the appropriation and control of water. Native Americans have particularly suffered the conse- quences of increased competition for water, with many indigenous communities facing water shortages due to upstream diversions (DeJong, 2009; Knack and Stewart, 1999). For many of these com- munities, the only recourse to regain access to water is through the courts. Archival records provide an important source for doc- umenting indigenous water control and management, but water use by Native Americans long predates the documentary record established with the arrival of Europeans (Doolittle, 2000; Hunt et al., 2005; Wright, 2006). The physical identification and dating of ancient and historic indigenous water-control features such as canals and reservoirs thus provide an important line of evidence to supplement archival records. The Rio San Jos e (RSJ) of western New Mexico (Fig. 1) is currently the subject of water rights litigation involving several parties, one of which is the Pueblo of Laguna, an indigenous agricultural com- munity with a centuries-long tradition of riverine irrigation along the RSJ and its tributaries (Ellis, 1979; Ferguson, 2007). Dams and water diversions in the upper RSJ basin have reduced stream flow through the Laguna Reservation and contributed to a dramatic reduction in irrigated land during the twentieth century (Ferguson, 2007 :49e50). Because agriculture is an important part of Laguna identity, the loss of opportunity to grow crops has repercussions that extend beyond mere economics. * Corresponding author. E-mail addresses: ghuck@email.arizona.edu (G. Huckleberry), tjf@email.arizona. edu (T.J. Ferguson), tammy.rittenour@usu.edu (T. Rittenour), christopher.banet@bia. gov (C. Banet), smahan@usgs.gov (S. Mahan). Contents lists available at ScienceDirect Journal of Arid Environments journal homepage: www.elsevier.com/locate/jaridenv http://dx.doi.org/10.1016/j.jaridenv.2015.11.004 0140-1963/© 2015 Elsevier Ltd. All rights reserved. Journal of Arid Environments 127 (2016) 171e186