About our ICOLLs

The Byron Shire is home to two intermittently closed and open lakes and lagoons, or ICOLLs:

  • Tallow Creek
  • Belongil Creek

These two creeks open and close to the ocean depending on the build-up of sand at the mouth of the creek.

They are important ecosystems sustaining fish, birds, marine life, vegetation and wetlands. They are also highly significant cultural use places for the traditional owners of this land, the Bundjalung of Byron Bay (Arakwal) people.

Find out more about Council's management of its ICOLLs and when it is necessary and permissible to artificially open a closed lagoon. 

The difference between estuaries and ICOLLs

An estuary is a partly enclosed coastal body of water with one or more rivers or streams flowing into it, and with a free connection to the open sea.

An ICOLL (an intermittently closed and open lake and lagoon) opens and closes to the ocean depending on the build-up of sand at the mouth of the creek.

Estuaries, located at the boundary of marine and freshwater ecosystems, form a transition zone between river environments and ocean environments. Estuaries vary in shape and size ranging from:

  • coastal embayments
  • drowned river valleys
  • coastal lakes
  • smaller intermittently closed and open lakes and lagoons (ICOLLs). 

Estuaries offer immense value from an ecological, social and economic perspective. Estuarine foreshores are desirable places on which to live and work and their waterways are popular for a wide variety of active and passive recreational pursuits.  There are three estuaries within Byron Shire: