Lake Dunlap is a reservoir on the Guadalupe River near the town of New Braunfels in Guadalupe County, Texas, United States. The reservoir was formed in 1931 by the construction of a dam to provide hydroelectric power to the area. Management of the dam and lake was assumed by the Guadalupe-Blanco River Authority on May 1, 1963. Lake Dunlap serv…Lake Dunlap is a reservoir on the Guadalupe River near the town of New Braunfels in Guadalupe County, Texas, United States. The reservoir was formed in 1931 by the construction of a dam to provide hydroelectric power to the area. Management of the dam and lake was assumed by the Guadalupe-Blanco River Authority on May 1, 1963. Lake Dunlap serves as a venue for outdoor recreation, including fishing and boating. In 2019, the dam failed, draining the lake. The repair was completed in August 2023, and the lake fully restored by the end of October that year.