Building codes for residential housing in California have prevented the installation of home water-recycling systems ("grey water") that use the water that drains from showers, washing machines, dishwashers, and sinks (not toilets) to irrigate lawns and gardens. Now that we are in the worst drought ever recorded, these codes need to be rewritten to encourage the installation of these systems. The benefits to the environment are obvious, but mandating builders to install water-recycling systems would also be an economic stimulus, in that it would foment the creation of many new small businesses by plumbers and landscapers that specialize in these installations. Such businesses are already profitable in Mexico, as they have had mandated grey water systems for years. It is time that we follow the example of our neighbor to the south, and overturn the wasteful laws governing home water use and replace them with sustainable ones.