It’s not the water itself that smells. In fact, the City of Santa Ana conducts regular monitoring tests throughout the water distribution system to check for any odors. This issue is typically related to organic materials that have been discarded into a kitchen drain or another sink. Over time, these materials can accumulate and decay within the drain, creating an unpleasant odor. There could also be bacteria locked in the P-trap of your bathroom sink drain or a buildup of bacteria in your pipes.
To remedy this issue, routinely clean drain stoppers, faucet aerators and flush the P-trap and/or garbage disposal, the sink and the overflow with a solution of household chlorine bleach. If this awful rotten-egg smell is persistent and the issues continue, you may need to contact a qualified plumber to address it.