Everglades Topography: Flat, Wet, and Subtly Sculpted

The Everglades topography defies drama. Maximum elevation: 2.4m (8 ft) above sea level. Minimum: sea level. Slope: ~3 cm/km southward. It's a 1.5M-acre sheet of water on limestone.

Key Features

• Sawgrass Plains: Cladium jamaicense monoculture on marl soils. 60% of area. "River of Grass."
• Tree Islands (Hammocks): Elevated (30–90 cm) on limestone highs. Hardwoods (gumbo limbo, mahogany, live oak). Wildlife refuges. 1,000s scattered.
• Sloughs: Deeper channels (0.5–1.5m). Shark River Slough (west), Taylor Slough (east). Main flow paths. Aquatic fauna highways.
• Marl Prairies: Shorter hydroperiod. Calcareous periphyton mats. Cape Sable seaside sparrow habitat.
• Mangrove Zone: Coastal transition. Red/black/white mangroves. Nursery fisheries. Carbon sequestration.
• Cypress Domes/Strands: Dome = circular (solution hole). Strand = linear (fault/fracture). Bald cypress, pond cypress.
• Coastal Prairies: Saline, fire-maintained. Cape Sable.

Hydrologic Dynamics

• Wet season (May–Oct): 1,000–1,500 mm rain. Sheetflow 30 m/day. Water depth 30–90 cm.
• Dry season (Nov–Apr): <50 mm rain. Evapotranspiration > rainfall. Water retreats to sloughs, gator holes, canals.
• Fire: Dry season lightning → sawgrass fires. Rejuvenates, prevents woody encroachment.

Human Alteration

Canals (2,100 km) + levees → compartmentalization (WCAs). Drainage → soil oxidation (subsidence 1–3 cm/yr in EAA). Seepage barriers → altered gradients. Restoration = re-plumbing.

Topography so subtle, a ruler measures it. Ecology so sensitive, a centimeter decides: sawgrass or slough, fire or flood, life or salt.