Posted on 25 February 2021 By Rob Katherman WRD Robles Advanced Water Treatment Facility The Water Replenishment District of Southern California (WRD) is the largest groundwater agency in the State of California, managing and protecting local groundwater resources for over four million residents. WRD's service area covers a 420-square-mile region of southern Los Angeles County, the most populated county in the United States. The 43 cities in the service area, including a portion of the City of Los Angeles, use about 215,000 acre-feet (70 billion gallons) of groundwater annually which accounts...