A slough ("sloo") is a swamp with water a little deeper and with a measurable flow. This is probably the most typical scene of what people think of in the Everglades. Water, grasses, a Great Blue Heron. Tree Hammocks in the back. The water is shallow (it is the dry season) and clear as can be. By the time it gets to this location, it has been filtered for many miles. it will travel to Florida Bay.