The dark, soft sediment found in the marshes of South Carolina is the product of decay, including spartina grasses and fish, crabs, shrimp and other marine life. As anaerobic bacteria is doing the work, hydrogen sulfide is released - thus the smell of rotten eggs.

What is that smell in Charleston?

The smell we are all inhaling is: Pluff Mud. Whether you find the smell of pluff mud nostalgic or repulsive, you will probably agree that it is definitely Lowcountry and definitely unique! In fact, most visitors actually notice the smell almost immediately and often ask locals what it is!

What does river mud smell like?

Mudflats smell like rotten eggs when a smelly gas called hydrogen sulfide is let off by tiny living things called microbes living in it.