The Coastside County Water District board of directors will consider on Tuesday asking its customers to voluntarily reduce outdoor water consumption by 10 percent. The move by the municipal water agency serving Half Moon Bay and El Granada comes amid a historic statewide drought. The CCWD relies on water purchased from the San Francisco Public Utilities Commission and that agency is asking for voluntary irrigation reductions of 10 percent. That is because of low storage in the Hetch-Hetchy watershed, which is exacerbated locally by similarly low levels in area reservoirs. âSuccessful voluntary reductions in water use may delay the need for mandatory rationing,â according to a staff report accompanying Tuesdayâs meeting agenda. The staff report says the ask would also position the district to impose a mandatory rationing program should conditions worsen.