Lagoon Facts & Topics


  • IRL is North America's most diverse estuary
  • Varies in width from .5 to 5 miles; average 3' depth
  • 156 miles long
  • Spans Volusia, Brevard, Indian River, St. Lucie, and Martin counties
  • Includes Mosquito, Banana River and Indian River Lagoons
  • Brackish water - mixture of fresh and salt waters
  • 2000+ Plant species
  • 600+ Fish species
  • 300+ Bird species
  • 53 threatened or endangered species


The Indian River Lagoon stretches 156 miles from Ponce De Leon Inlet in New Smyrna Beach in the north, to Jupiter Inlet near West Palm Beach to the south.  The Indian River Lagoon system includes Mosquito Lagoon, Banana River Lagoon, and Indian River. This is a unique and diverse system that connects Volusia, Brevard, Indian River, St. Lucie, and Martin counties. A large portion of the IRL system, 71% of its area and nearly half its length, is within Brevard County.  (credit, 2007)




How did the Indian River Lagoon get polluted? - For decades, the IRL has been severely threatened by rapid development, habitat destruction, overharvesting and pollution. The northern half of the Lagoon has only a few outlets to the sea, so it does not flush very rapidly which means that stormwater runoff, wastewater treatment discharges, septic systems and excess fertilizer applications have flooded the Lagoon with harmful nutrients and sediments. The nutrients feed the massive algal blooms, and together, with the suspended particles, block the sun from reaching the seagrass. As a result, the seagrass dies, oxygen levels fall and fish suffocate. The rotting fish produce more available nutrients which leads to more blooms.  (credit


Indian River Lagoon Watershed

Mosquito Lagoon Photo Credit John Emerson

"The Indian River Lagoon (IRL) watershed's land features date back to 420,000 years ago, shaped by the rise and fall of the sea. The basin's major waterbodies are three elongated saline lagoons: Mosquito Lagoon, the Indian River Lagoon, and the Banana River. These lagoons separate mainland Florida from a strip of barrier islands that extends north and south of two unique land features, Cape Canaveral and Merritt Island." (source FL DEP).  Click here for more facts about the Indian River Lagoon watershed.

Florida's Mangroves Protect the Lagoon

"Florida's estimated 469,000 acres of mangrove forests contribute to the overall health of the state's southern coastal zone. This ecosystem traps and cycles various organic materials, chemical elements and important nutrients. Mangrove roots act not only as physical traps but provide attachment surfaces for various marine organisms. Many of these attached organisms filter water through their bodies and, in turn, trap and cycle nutrients." (source FL DEP).  Click here for more facts about Mangroves.


Lagoon Minutes - One minute audio posts about Lagoon facts


Straight Talk Events - the presentations of each Straight Talk event hosted by the Coalition