Water in the desert

[heirodule]

So according to the thirst rules, in a hot climate, you need 2-3 galons of water a day. But you can go 1 day without water with no penalty.

Say you start with 15 gallons. Can you do this

Day 1: don't drink water: 15 gal left
Day 2: drink 3 gals 12 gal left
Day 3: don't drink: 12 left
Day 4: drink: 9 left
Day 5: no: 9 left
Day 6 drink: 6 left
Day 7 no: 6 left
Day 8 drink: 3 left
Day 9 no: 3 left
Day 10 drink: 0 left
Day 11 no: 0 left
Day 12 NEED WATER BADLY

And why do the Survival rules have no modifyer for finding water in desert conditions? it's a DC 10 in a lake, and a DC 10 in the Gobi.

 

[werk]

So according to the thirst rules, in a hot climate, you need 2-3 galons of water a day. But you can go 1 day without water with no penalty.

Say you start with 15 gallons. Can you do this...

And why do the Survival rules have no modifyer for finding water in desert conditions? it's a DC 10 in a lake, and a DC 10 in the Gobi.

If your DM is the type to pass the days in single chunks, and doesn't mind the suspension of disbelieve or the rules' loophole....sure, you can do that.

Would you say finding water in the desert is:
Very easy (0)
Easy (5)
Average (10)
Tough (15)
Challenging (20)
Formidable (25)
Heroic (30)
Nearly impossible (40)
?

DM's set DC.

 

[Infiniti2000]

I choose:

Would you say finding water in the desert is:
Very easy (0)

My PC is a cleric.

 

[JonnyFive]

no casters in the party? buy a decanter of endless water. problem solved.

 

[frankthedm]

And why do the Survival rules have no modifyer for finding water in desert conditions? it's a DC 10 in a lake, and a DC 10 in the Gobi.

All skills have that modifier.

Favorable and Unfavorable Conditions
Some situations may make a skill easier or harder to use, resulting in a bonus or penalty to the skill modifier for a skill check or a change to the DC of the skill check.

The chance of success can be altered in four ways to take into account exceptional circumstances.

Give the skill user a +2 circumstance bonus to represent conditions that improve performance, such as having the perfect tool for the job, getting help from another character (see Combining Skill Attempts), or possessing unusually accurate information.
Give the skill user a –2 circumstance penalty to represent conditions that hamper performance, such as being forced to use improvised tools or having misleading information.
Reduce the DC by 2 to represent circumstances that make the task easier, such as having a friendly audience or doing work that can be subpar.
Increase the DC by 2 to represent circumstances that make the task harder, such as having an uncooperative audience or doing work that must be flawless.

Conditions that affect your character’s ability to perform the skill change the skill modifier. Conditions that modify how well the character has to perform the skill to succeed change the DC. A bonus to the skill modifier and a reduction in the check’s DC have the same result: They create a better chance of success. But they represent different circumstances, and sometimes that difference is important.

 

[Vorput]

So according to the thirst rules, in a hot climate, you need 2-3 galons of water a day. But you can go 1 day without water with no penalty.

Say you start with 15 gallons. Can you do this

Day 1: don't drink water: 15 gal left
Day 2: drink 3 gals 12 gal left
Day 3: don't drink: 12 left
Day 4: drink: 9 left
Day 5: no: 9 left
Day 6 drink: 6 left
Day 7 no: 6 left
Day 8 drink: 3 left
Day 9 no: 3 left
Day 10 drink: 0 left
Day 11 no: 0 left
Day 12 NEED WATER BADLY

And why do the Survival rules have no modifyer for finding water in desert conditions? it's a DC 10 in a lake, and a DC 10 in the Gobi.

I'm relativly sure realistically this equates to simply rationing your water.

 

[Stalker0]

I'm relativly sure realistically this equates to simply rationing your water.

Agreed, so you really only need 1-1.5 gallons a day.

 

[ken-ichi]

If you are concerned about the long term rationing of water like this then apply a house rule like the following. I also don't really like the fact that all the minuses you have been taking to the check go away after a single day of drinking.
So a example house rule:
Keep track of every "free" day when not consuming water.
You are allowed to remove one of these tallys for every consecutive day of normal water consumption after the first.

You don't need to make a Con check on a day that you drank an adequate amount of water even if you have Tally marks remaining. Your body is still weak from the deprevation so if you immediately go back to not drinking you still suffer the same penalty that you were at.

Day 0 Drink.
Day 1 Skip. Skip Tally 1 "Free Day"
Day 2 Skip. Skip Tally 2 Con check.
Day 3 Drink. Skip Tally 2. No check needed due to drinking today.
Day 4 Skip. Skip Tally 3. Must make a Check vs Dehydration.
Day 5 Drink. Skip Tally 3.
Day 6 Drink. Skip Tally 2 due to 2nd successive day of drinking.
Day 7 Drink. No Tally left -2 from 3rd successive day of drinking.

 

[heirodule]

to add a wrinkle, Sandstorm specifies that in warmer bands, the 24 hours + con score gets cut shorter and shorter at hot ranges

Hot: 12 + con score
Severe heat: 6 + con score

So in the deset, A 12 con gets you 24 hours or 18 hours.

That's complictated needlessly by the fact that in the desert, you're never at the same heat band all the time.

What would be the daily water needs for a day that's 40 degrees all night, hot from 7am to noon and 3 pm to 7pm and severe heat from 12-3pm? Who knows. 2 gallons I guess.

 

[Abe.ebA]

On the one hand, being able to go a day with no water and needing about 3 gallons a day is a lot different from needing 3 gallons every other day (as happens in the proposed plan). You sweat out so much water a day and you have to replace it, so by day 3 you're trying to replace 2 days of lost liquid with one day worth of new liquid.
Personally, I'd rule that as soon as you drop below a gallon of water every eight hours you hit fatigued status. Probably make you roll a Fort save by day 7 or 8 of your 16 day plan to see if you become exhausted with increasing DCs as the days wear on, but that's just me.

On the other hand, there are a lot of ways to increase your survivability in extreme environments. In a desert, for instance, wearing long sleeves and a makeshift turban will keep you from sweating as much and reduce the amount of liquid you need. As someone else mentioned, a desert's temperature changes dramatically after sundown so if you spend your days under shelter and walk at night you'd reduce your need for water even more.

Yet another example of realism falling beneath the granularity of d&d. So yeah, by the RAW what you say would work but if I were running a desert survival adventure where finding reliable hydration were one of the challenges I probably wouldn't let it slide. But I'd also let everyone know how I was going to handle it beforehand.