The Bay Area, like only 2 percent of the world, has a Mediterranean climate. This means that we have cool, wet winters and summer droughts.
Thus, it is important to have landscaping that uses drought-tolerant plants, efficient irrigation, and employs other water-saving methods.
Here are three drought survial guides you can download:
Drought Survival 101 - Water Your Lawn
Drought Survival 101 - Trees and Shrubs
Drought Survival 101 - Benefits of Mulch