Most people take it for granted. You turn the faucet on, and water comes out.

But it isn’t that simple. In fact, it’s far more complicated to fill a glass with clean drinking water.

That’s one of the reasons why the City of San Diego’s Public Utilities Department is mailing residents the annual Drinking Water Quality Report this week.

“A lot of people just think that when you turn the tap water on, it’s just coming from the lakes and the streams,” said Michael Simpson, the Senior Water Operations Supervisor at the Alvarado Water Treatment Plant near Lake Murray.