Lady Bird Lake is a river-like reservoir on the Colorado River in Austin, Texas, United States. The City of Austin created the reservoir in 1960 as a cooling pond for a new city power plant. The lake, which has a surface area of 416 acres, is now used primarily for recreation and flood control. The reservoir is named in honor of former First Lady of the United St…Lady Bird Lake is a river-like reservoir on the Colorado River in Austin, Texas, United States. The City of Austin created the reservoir in 1960 as a cooling pond for a new city power plant. The lake, which has a surface area of 416 acres, is now used primarily for recreation and flood control. The reservoir is named in honor of former First Lady of the United States Lady Bird Johnson.