As drought and water shortages become California’s new normal, more and more of the water that washes down drains and flushes down toilets is being cleaned and recycled for outdoor irrigation. But some public officials, taking cues from countries where water scarcity is a fact of life, want to take it further and make treated wastewater available for much more — even drinking. “This is a potential new source of water for California,” said former Assemblyman Rich Gordon. “We need to find water where we can.”