Some environmental impacts include the tides, storm water drainage, and salinity. These factors impact the lagoon on a daily basis.
Salinity plays an important environmental factor in Lake Worth Lagoon, too much or too little can cause some species to die off. The salinity range for Lake Worth Lagoon is 20 to 36 parts per thousand (ppt). The salinity difference between fresh water and the ocean varies greatly where freshwater is zero parts per thousand and the ocean, with an average value of 35 parts per thousand. When freshwater flows in from the surrounding watershed, it can cause drastic changes in the lagoon’s salinity levels. These changes harm plant and animal life in the lagoon.
When it rains, water that runs off the land called storm water, mixes with pollutants such as pesticides and fertilizers. Storm water carries sediment, organic matter, and pollutants from neighborhoods and agricultural lands into the lagoon causing harm to fish and other wildlife. The storm water drainage also forms muck sediments that cover the sandy bottom of the lagoon stifling seagrass and bottom-dwelling organisms.
Tides also play an important role in the lagoon. Since the lagoon is connected to the ocean it obtains fresh ocean water from the in-coming tides through the inlets. As the out-going tide rushes out to sea the pollutants are carried along and get flushed out. Without this kind of flushing effect it is hard for wildlife to flourish.
Human impacts include dredging, filling, shoreline alteration, shoreline hardening, and pollution. These factors impact the lagoon on a daily basis.
Before settlers came to Lake Worth Lagoon it was a freshwater lake with no connections to the ocean. When settlers did arrive many changes were made to accommodate living and traveling in that area. Travel was mostly done by boat and to avoid rough seas, inlets were hand-dug at the northern end of Lake Worth.
In addition to dredging, settlers also replaced mangrove shorelines with concrete structures called seawalls to protect the shoreline from erosion. Today the lagoon is 20 miles long, half a mile wide, and has an average depth of six feet.