We're stranded in the desert, and need to find our way to safety, civilisation, and rescue. Along the way, we need to husband two important resources: hydration and health, lest we expire from want of one or the other. It's a pretty tense little survival story. By the time I got to the ending, I was just one point up from death in both resources, and I don't get the impression of there being a very easy way of getting or conserving a lot of one or the other.
In a way, it's a bit of a throwback to the classic gamebooks, albeit without the dice-based combat. It's not always clear what a choice will lead to, but the results are never entirely arbitrary either. It's perhaps to be expected, given the unfamiliarity of the terrain. You could make an informed guess as to the preferability of one choice over another, but ultimately it is still a guess ... and there are times when it is clear that, say, three things need to be done but you only have time for two. We're still in control, always: I never had the sense that we could just flip a coin and hope for the best.
There are some odd grammatical errors, which I will assume are only typos. For the most part, the writing is pretty decent -- it doesn't try too hard, it doesn't try too little, it's just right for the story. It does describe a lot of the survival tricks in what seems to be very realistic terms, so that's a big plus.
Dry biscuits augmented with wild berries scavenged from the surrounding woods, and black coffee brewed over a campfire.