Freshwater wetlands occur throughout Miami-Dade, particularly in western and southern parts of the county.

Wetlands provide areas for aquifer recharge, retention of flood waters and fish and wildlife habitat. They also naturally protect water quality. Therefore, permits are required for work in wetlands.

Coastal, or saltwater, wetlands consist of salt marshes and mangrove swamps.

Salt marshes consist mostly of grasses and herbaceous plants, which provide the coastline with protection from direct wave action.