Every year, Californians get a report card from their water department telling them if something is wrong with their water. These polished brochures typically begin by laying out all the great things water agencies are doing with ratepayer money. It would be easy to just throw them away. But near the end is series of hard-to-decipher charts that show what sort of contaminants have been found in their drinking water. These are things, like bacteria, that could make someone sick immediately and others, like disinfectant byproducts, that could give someone cancer over time.