- "A surreal stagnant oasis in the desert. The water might look clean but it can burn through a man's lower intestine in seconds."
- ―GTA V Manual
It is described as "a putrid, salt-rich lake whose waters are unlikely to be home to anything you’d want to go fishing for". The Alamo Sea is located at the base of Mount Chiliad. The sea is probably toxic, as it is described as being able to "burn through a man's lower intestine in seconds".
Despite these claims, the player is able to wade and swim in the water freely. However, large amounts of trash and debris litter the shores of this lake, further hinting of how polluted the sea is.
Alamo Sea is based on the Salton Sea in Southern California.