The Center for Archaeological Studies (CAS) at Texas State University-San Marcos conducted archaeological monitoring investigations in association with the Spring Lake Aquatic Ecosystem Restoration Project between October 2011 and July 2012. These archaeological monitoring investigations were the result of mitigation efforts proposed in the Historic Properties Treatment Plan drafted in accordance to the Memorandum of Agreement (MOA) signed and enacted between the U.S. Army Corps of Engineers, Texas State University-San Marcos, and the Texas Historical Commission. Archaeological monitoring investigations consisted of monitoring all demolition and ground-disturbing activities conducted during the course of the Spring Lake Aquatic Ecosystem Restoration Project. All cultural deposits or potential cultural deposits were identified, assessed, and documented during the project by archaeological monitors, and time-diagnostic artifacts were collected. Locations of deposits were recorded and uploaded to a GIS database of the Spring Lake area for future reference. No significant cultural remains were identified or impacted by demolition and ground-disturbing activities of the Spring Lake Aquatic Ecosystem Restoration Project.