A pilot project in California is using captured rainwater to supply wash water for winemaking, saving thousands of gallons of freshwater per day.
The project uses a GE reverse osmosis system and total organic carbon analyzer at the University of California Davis winery. Rainwater is captured via downspouts in a 1,200 gallon tank, then feeds through a 50-micron filter before being pumped into two 45,000 gallon storage tanks that supply the treatment system. Rainwater contains fewer contaminants than groundwater sources, meaning it requires less filtration to be purified to a usable level for washing.