Weather Insider: Odor Advisories

When people visit the Coachella Valley, the Salton Sea isn't usually at the top of most people's to-do lists... and for good reason. The Salton Sea often has a bit of an unpleasant odor. This is because of Hydrogen sulfide, a gas which is well known for giving rotten eggs their distinctive smell.

As with all bodies of water, there are nutrients and gases dissolved within. Since the Salton Sea is endorheic (meaning all the water that drains into the Salton Sea will not drain out), the amount of nutrients is fairly limited. If there's a sudden bloom of algae in the Salton Sea, it can use up all the oxygen in the water, causing the fish to suffocate and die. As these fish rise to the surface, they begin to rot. This releases the Hydrogen sulfide gas which the southerly winds may carry into the Coachella Valley.