U.S. Department of the Interior Prepared in cooperation with The Chitimacha Tribe of Louisiana; Open-File Report 2019–1030 U.S. Geological Survey Gulf Coast Prairie Landscape Conservation Cooperative

91°35' 91°34' 91°33' 91°32' 91°31' 91°30' Introduction

Situated in the Mississippi Alluvial Plain of the Gulf Coast Prairie Landscape Conservation Cooperative (GCP 29°55' LCC), the Chitimacha Tribe is one of four federally recognized tribes in Louisiana. The Tribal seat, trust lands/ reservation, and adjacent Tribal owned lands are located near Charenton, Louisiana, totaling nearly 1,000 acres. The Chitimacha, with a population of approximately 1,400 people, are currently impacted by storm surge, which is expected to increase with climate change. The additional stress from storms will likewise increase the vulnerability to catastrophic 10 impact in the event of a breach in the Atchafalaya Basin 12 Spillway levee. A collaborative effort between the U.S.

10 Geological Survey (USGS) and the Chitimacha Tribe has 10 been initiated to provide resources and expertise to increase 12 the Tribe’s ability to prevent, plan, and prepare for these 10 environmental challenges. By enhancing technical skills, providing access to environmental data, and increasing 10 West Atchafalaya Basin Spillway levee awareness of environmental issues, the Chitimacha will be better prepared to plan and adapt to the environmental 101010 29°54' impacts facing their lands related to land use and climate change. For this project, USGS researchers asked how Chitimacha Tribal Lands might be impacted by future sea level rise scenario projections. These models illustrate some flooding within the northernmost boundary of Chitimacha Tribal Lands. 10 Methods and Data

This map of the Chitimacha Tribal Lands and surrounding 12 area illustrates the magnitude of potential flooding resulting from future sea level rise at 2 feet, 4 feet, and 6 feet above 14 current sea level. These projections do not account for unusual high tide and storm surge events, which could 14 lead to increased flooding. Sea level rise data for this map display were downloaded from the National Oceanic and 29°53' CharentonCharentonCharentonCharenton 14 Atmospheric Administration (NOAA) Office for Coastal Management through the NOAA Sea Level Rise Viewer 14 (NOAA, 2012; https://coast.noaa.gov/slr). Existing waterbodies visible in the imagery and derived from the 12 high-resolution version of the USGS National Hydrography dataset (USGS, 2013), such as streams/rivers, canals/ditches, 14 14 10 lakes/ponds, and so on, were removed from the NOAA sea level rise layers and appear in this map to delineate the sea 14 level rise projections surrounding them. Contours were 10 12 added to show elevation ranges at 10, 12, and 14 feet. These 12 contours were created from a 15-meter bare-earth digital elevation model developed from the USGS 3D Elevation Program Coastal National Elevation Dataset (USGS, 2017) 14 10 topographic model of the Northern Gulf of Mexico.

10 References 29°52' National Oceanic and Atmospheric Administration (NOAA), 12 10 2012, Sea level rise viewer: 1-6 ft sea level rise inundation 10 extent: Accessed March 18, 2016, at http://www.coast.noaa. 14 12 gov/slr. U.S. Geological Survey (USGS), 2013, National

12 Hydrography geodatabase: The National Map viewer: Accessed March 18, 2016, at https://nhd.usgs.gov/. U.S. Geological Survey (USGS), 2017, 3DEP products and Bayou Teche services: Accessed March 18, 2016, at https://nationalmap. 12 14 12 gov/3DEP/3dep_prodserv.html. 10

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Base from United States Department of Agriculture EXPLANATION 0 0.5 1 MILE National Agriculture Imagery Program, 2015 Universal Transverse Mercator zone: 15 North American Datum of 1983 Sea level rise (SLR) Central Meridian: -93 00 0 0.5 1 KILOMETER 4-band, 1-meter 2 feet

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Chitimacha Tribal Lands

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Study area

For more information on the USGS—the Federal source for science about the Earth, its natural and living resources, natural hazards, and the environment—visit https://www.usgs.gov/ or call 1–888–ASK–USGS (1–888–275–8747). For an overview of USGS information products, including maps, imagery, and publications, visit http://store.usgs.gov/. Any use of trade, firm, or product names is for descriptive purposes only and does not imply endorsement by the U.S. Government. Although this information product, for the most part, is in the public domain, it also may contain copyrighted materials as noted in the text. Permission to reproduce copyrighted items must be secured from the copyright owner. Potential Sea Level Rise on Chitimacha Tribal Lands in Louisiana Suggested citation: Spear, K.A., Jones, W., Griffith, K., Tirpak, B.E., and Walden, K., 2019, Potential sea level rise on Chitimacha Tribal Lands in Louisiana: U.S. Geological Survey Open-File Report 2019–1030, By 1 sheet, https://doi.org/10.3133/ofr20191030. Kathryn A. Spear,1 William Jones,1 Kereen Griffith,1 Blair E. Tirpak,1 and Kimberly Walden2 1U.S. Geological Survey ISSN 2329-132X (online) 2019 2The Chitimacha Tribe of Louisiana https://doi.org/10.3133/ofr20191030