The Trinidad Lake project was started and completed in 1925. The reservoir, located just south of Trinidad in southwestern Henderson County (centered at 32°07' N, 96°06' W), has a capacity of 7,800 acre-feet and a surface area of 753 acres at an elevation of 285 feet above mean sea level. Water is pumped from the Trinity River to maintain this level. There is no significant drainage area to contribute material to this off-channel storage. The lake is surrounded by flat to rolling terrain surfaced by sandy and clay loams that support water-tolerant hardwoods, conifers, and grasses.