On February 27, 2023, in a much anticipated decision, California’s Second District Court of Appeal overruled the trial court by determining that the State Water Resources Control Board (“State Water Board”) did not violate its duty to prevent waste and unreasonable use of water when it declined to investigate wastewater discharges from four Los Angeles area Publicly Owned Treatment Works (“POTWs”). The Court found that the State Water Board’s duty under state law to prevent waste and unreasonable use of water is “highly discretionary” and does not require an investigation or assessment of every allegation of unreasonable use. (Los Angeles Waterkeeper v. State Water Resources Control Board (2023)__Cal.App.5th__)