Translation:If the water rises, the village would raise the protection.
The English sentence isn't quite grammatical: is the German sentence?
In English, a better phrasing in the subjunctive ((perhaps among others) would be "If the water ROSE, the village would raise the protection." Alternatively, you could say "If the water rises, the village will increase the protection. In any case, the English sentence as given has a conflict in tense.
I agree. I believe I translated it as "increase' or something like that and it was accepted. The sentence is still a little odd, whether it means increasing the insurance (whoops! too late for that!) or piling on more sandbags, but if the German sentence doesn't mean something that isn't clear in the English translation, I'll happily move on.
The German grammar seems wrong to me. Correct versions:
"Wenn das Wasser steigt, WIRD das Dorf den Schutz erhöhen." (The condition may still happen.) Translation as I see it: "If the water is rising, the village will ..."
"Wenn das Wasser stiege, würde das Dorf den Schutz erhöhen" (The condition is not true. Traditional wording.) "Wenn das Wasser steigen würde, würde das Dorf den Schutz erhöhen" (The condition is not true. Modern lazy wording.) Translation (by my German inexperienced mind): "If the water was rising, the village would ..."
As to "Schutz": There is a term "Hochwasserschutz" meaning dikes and other protections. You could "den Hochwasserschutz erhöhen" meaning not to raise the dykes but to raise the general effort, or even the general protection.
There is also "Versicherungsschutz". So the village(?) could raise the insurance cover or even the insurance protection.
Anyway the German sounds odd because the use of "Schutz" alone would only be plausible if "Hochwasserschutz" or "Versicherungsschutz" had been mentioned before. And of course the first thing that comes to mind, is to raise the dikes.