What is a coastal dune lake?
Coastal dune lakes are bodies of water found in dune ecosystems within two miles of the coast.
They’re typically shallow and irregularly shaped. Coastal dune lakes are usually permanent water bodies, but their water levels fluctuate substantially since they create transitory interchanges with the Gulf of Mexico. The lake-water is composed of both fresh and saltwater that comes from tributaries, groundwater seepage (from uplandsand from the Gulf), rainfall, exchange with the Gulf, and coastal storm surges. The lake-water is generally colored (e.g., tea or black colored) due to the dissolved organic matter it contains. This is a natural phenomenon, and it’s nothing to be worried about! While these lakes are exposed to normal weather conditions just like any lake, Florida’s coastal dune lakes are also tremendously impacted by hurricane activity (i.e., storm frequency, strength, and duration).
What is an outlet/outfall?
Why are the coastal dune lakes important?
According to the Florida Natural Areas Inventory, Walton County’s coastal dune lakes are imperiled globally because of rarity and critically imperiled in the state of Florida because of extreme rarity. They are also indispensable to our coastline as wetland systems that filter and store water, provide habitat for a wide variety of unique flora and fauna, and exist as a natural estuarine transition between the Gulf and upland areas. Coastal dune lakes are reportedly found in limited number throughout the world along the coasts of New Zealand, Australia, Madagascar, and in the United States along the coasts of Oregon, South Carolina, and Northwest Florida.