My pomegranate tree bear fruit even with minimum watering due to the restrictions and conservation of water for several years as a result of the drought that affected California for the past several years. I cut back on water usage by watering the lawn at a minimum only enough for the lawn not to die; the water saved on the lawn was used instead to water the fruit trees.
Pomegranate trees are known to be extremely drought-tolerant but with more watering it will have better fruit quality, the fruit will be bigger and the seeds will be juicier. Will it be sweeter? That remains to be seen.