I played it for a couple of hours and came up with some ideas.
1. With every melee swing draining water and the water (SP) item drops being relatively rare, even reaching the first extraction can become risky, especially with the starter weapons the take a lot of swings to use.
I have died of thirst and other other times came close when the items won't appear while scouring the whole map for items. If the game does not spawn a supermarket, the water survival is at least some RNG and it seems like it can create an unwinnable game by not spawning enough water to reach the end.
Last Stand Aftermath had a similar concept and they solved it by making it possible for the enemies to drop more of those items. Until the game starts dropping more water, I recommend playing the game without save-scum because of the high risk of item loss.
2. The most common non-water-related reason for dying is that enemies weirdly lock the player in and you cannot move or tell what particular enemy is blocking the movement. It might help if you could move a tiny bit past the enemy to simulate the real life not being 2D. Currently the enemies are like box cars that you cannot get past. The main problem is the no indication of what is going on when enemies lock you in in terms making the obvious thing to do to escape it more clear. Maybe a graphical highlight on the enemy that is blocking your movement.
3. I tend to die of thirst because the SP bar is on the other side of the screen whereas the main focus is in the center especially when melee'ing in short range. There could be an audio cue or an visual efect on the crosshair indicating low-water condition. The SP tends to go down fast especially during the Horde sequences with so many enemies around to swing at.
I have not played past level 2. It is either I run out of water while fighting or the enemies lock me in when I have a slow weapon like a sledge or a war axe.