During any Season other than Summer, the Lake will be dry and unusable. The players can walk over it during this time.
During Summer, the Lake will fill up with water when the ground is dry. There is an option to fish in the lake once it is filled. Using a Fishing Rod, Freshwater Fish and Crumpled Packages can be caught at any time of Day. There are 15 Fish or Packages, and one is refilled every 90 seconds. The chance of getting a Fish is 40%, and getting a Package is 60%.
There are 3 Fireflies on the Lake. They are not catchable while the Lake is full of water. These fireflies are refilled whenever the lake is refilled. These fireflies are the only source of renewable fireflies. To get the Fireflies, the player simply has to visit the Lake after summer, as it will then be dried up and the Fireflies will remain.
Making a small outpost near the Oasis can be beneficial as players will be staying at the Lake for long periods of time to fish out the various rare Blueprints only obtainable through Crumpled Packages that are exclusively found in the Lake.
Building a base around the oasis area may be a choice, because wildfires do not start there. However, there is the sandstorm effect and oasis is generally remote from other places, without cave and wormhole.