At one of Los Angeles’s main water treatment plants a few miles north of the Port of Los Angeles, a small-scale facility is demonstrating what might be part of the solution to the region’s water woes. The Pure Water Southern California Demonstration Plant facility uses membrane bioreactors, reverse osmosis, and ultraviolet radiation to process about 500,000 gallons of treated wastewater a day, further purifying it into something clean enough to use in industry, replenish the region’s groundwater, and potentially put back into the city’s drinking water system.