Sand to Mud to Redevelopment - Trinity Bay 1876 to 2012

The aim of this thesis is to investigate the environmental history of Trinity Bay, Cairns, specifically on the nature and causes of change to the pristine beaches and biodiversity of Trinity Bay, from the time of European settlement. Furthermore, this thesis will explore how those changes are influencing Trinity Bay today. The study takes a thematic approach, based on types of environmental change, and is drawn largely from historical archives, newspapers, local histories, and scientific sources. Following an Introduction, the first chapter explores the ‘discovery’ of Trinity Bay by Captain James Cook on the 10 June 1770 and the ensuing growth of Cairns. The main focus of this chapter is to use photographic and textual evidence to show that the foreshore of Cairns initially had pristine beaches, and that the drive to make a commercial port in the Bay by dredging resulted in turning these beaches into mudflats. Chapter Two examines the continued need for dredging by the early settlers for the advancement of shipping and colonisation. The consequential results of dredging to the mangrove and saltmarsh areas of the Bay and the devastating occurrence of Acid Sulfate Soils as a result of this are discussed. The hunting of dugongs and their rapid population decline, along with the depletion of seagrass beds within Trinity Bay, is the topic of Chapter Three. Chapter Four focuses on reclamation, and demonstrates that although this brought some benefits to Cairns, the long term degradation of the environment was significant. Chapter Five concludes the study by discussing the redevelopment of the foreshore of Trinity Bay in the past thirty years, as well as the presently proposed developments. The debate over the environmental issues from the proposed expansions of the international airport on the edge of the Bay and the influence of tourism on decisions made for development on Trinity Bay are also discussed. This study finds that the effects of European settlement on Trinity Bay and surrounding Cairns over the past 130 years have been dramatic and irreversible. Many of the development decisions for Cairns that were made in the past were for the betterment of Cairns, however little thought was given to the future effects of those decisions on the environment. The dredging of the Bay did increase the commercial viability of the Cairns port and the reclamation did improve public health and drainage of the town, but at a very high future cost to the environment. Most environmentalists would be appalled by the degradation of the marine life and mangrove and saltmarsh habitats, while others would see the ensuring tourism hub of North Queensland as an economic boom, thereby highlighting the complexities of environment-human interactions.