Does "Obwohl" require a direct causal relation between both sentences?

Question

I am a little bit confused with some input I got from Germans regarding the use of obwohl. I understand its meaning, but I am confused by one sentence where someone told me it “makes no sense”.

In the following example (from Usage differences of “obwohl” and “trotzdem”), it is clear that there is a relation between the two clauses:

Clarissa bleibt nicht im Bett, obwohl sie krank ist.

But I was corrected as follows:

Obwohl die Bevölkerung in den armen Ländern stärker wächst, steigt der Wasserverbrauch besonders in den reichen Ländern.
→ Während die Bevölkerung in den armen Ländern stärker wächst, steigt der Wasserverbrauch besonders in den reichen Ländern

I was told that “it makes no sense” and there is no relation between the first clause and the second one. My rationale behind this sentence is: One would expect the water use to increase more where the population has grown more, but this is not what happened.

The question is: Does obwohl require a direct causal relation such as the following:

I am sick. → I should stay in bed.
The population grew. → The water consumption should increase.

If so, would this sentence be correct?

Obwohl die Bevölkerung in den reichen Ländern nicht so stark wächst, steigt der Wasserverbrauch besonders in diesen Ländern

Answer 1

Obwohl is very similar to although in English and there are no unexpected requirements to using it. Hence your example sentence is fine:

Obwohl die Bevölkerung in den armen Ländern stärker wächst, steigt der Wasserverbrauch besonders in den reichen Ländern.

The usage of obwohl here reflects that the reality is contrary to the expectation, namely that water consumption primarily follow population increase.

When reading this sentence, the stress should be on reichen. I think the fellow's confusion stems from unjustifiedly rendering your sentence as this implausible sentence:

Obwohl die Bevölkerung in den armen Ländern stärker wächst, steigt der Wasserverbrauch - besonders in den reichen Ländern.

Although such a deliberate addition of punctuation is not justified and he should have admitted his mistake, in the very least on second glance, this can be prevented in many ways, either replacing words, as one answer suggested, or moving besonders:

Obwohl die Bevölkerung in den armen Ländern stärker wächst, steigt der Wasserverbrauch in den reichen Ländern besonders.

Your second sentence with obwohl is equally fine. There is absolutely no reason to prefer während. The latter does nothing but introduce some ambiguity, as to whether you want to express temporal or logical relationships.

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Per the request of the original poster, I now go on a detour to explain what's wrong with the dashed sentence. Most people may want to skip this to avoid being confused.

Essentially, the dash severes the link between den armen and den reichen. It is now no more possible to tell, what stärker compared. It could be anything, especially a point in time. The basic claim now becomes:

Obwohl die Bevölkerung in den armen Ländern wächst, steigt der Wasserverbrauch.

That, in turn, means that the speaker assumes a model of water consumption in which it it drops when population increases. That is not illogical in the mathematical sense, but implausible, if said without further clarification.

We can of course construct pathological models in which such a thing happens. Let's say, the desert kingdoms of Insania have but a few inhabitants. Most of them live on a cup of water per day, but the crazy Sheik wastes water in his gardens. From time to time inexplicable population explosion multiplies the number of his subjects, who rebel and in a bloody struggle force him to stop wasting water. A native of Insania might indeed exclaim:

Obwohl die Bevölkerung in den armen Ländern stärker wächst als in Insania, steigt der Wasserverbrauch.

But even in this insane scenario, the part after the dash would not fit in. To allow for that we must construct an even more surreal model: Insania is in fact a federation of states. The rich states Koeteria, Perversia and Takeallia waste water, while the poor states suffer. Every once in a while, inexplicably, the population of the poor rises so much, that they can force the rich states to spend less water.

Now the native of Insania has learned that population increase in the poor states means reduction in wasting water and in fact reduction in overall water consumption!

Thusly conditioned he may now exclaim:

Obwohl die Bevölkerung in den armen Ländern stärker wächst denn je zuvor, steigt der Wasserverbrauch - besonders in den reichen Ländern. ,

warning his fellow citizens about the imminent rebellion!

Answer 2

The first clause tells us that the population in poor countries increases heavily. If you introduce a contradicting point to that, a listener expects a surprising fact that relates to that statement, i.e. relating to the increasement of population in poor countries. Examples:

Obwohl die Bevölkerung in den armen Ländern stärker wächst, steigt der Wasserverbrauch dieser Länder nicht.
Obwohl die Bevölkerung in den armen Ländern stärker wächst, steigt der weltweite Wasserverbrauch nicht.

In your example, however, the surprising fact turns out to be a fact about rich countries. This statement is not really a contradicting point to the first statement. Sort of. But you can replace one word, and everything's different.

Obwohl die Bevölkerung in den armen Ländern stärker wächst, steigt der Wasserverbrauch ausgerechnet in den reichen Ländern.

It doesn't need to be the word ausgerechnet, but now the statement is that you would expect to have an increase of water consumption in poor countries but, surprisingly, the consumption increases in rich countries.

That being said, I'm not implying that besonders is the wrong word in context. I'm just of the opinion that this word is the cause of some misconception and another word might just be the better choice.

Still, the sentence isn't perfect yet. I would either drop "stärker" from the first clause, or also add it to the second one. But that's a matter of details.

Während, on the other hand, conveys a slightly different idea. After reading the first clause, you expect to hear a fact about countries that oppose the poor ones, i.e. the rich countries. It doesn't need to relate that strongly to the idea expressed in the first clause; however, it shouldn't be about something totally different.

In conclusion: both sentences are absolutely fine, you just might want to think about a slightly improved way of stressing why the second statement is the suprising contradiction to the first one.