Spatial variability of environmental field data between two adjacent tidal-inlet entrances

This study is part of a broader research project to build longer, more durable and stable tidal-inlet entrance channels in Currumbin and Tallebudgera Creeks. The sediment exchange and associated maintenance dredging of the inlets are also inherently linked to the development of a strategy to address the present vulnerability of the development-backed, open coast beach situated between the two inlets. These creeks are two of several small tidal inlets in south-eastern Queensland, Australia. There is a long morphological history of changes to the surrounding beaches, which are interconnected to the spatial changes of the mouth and entrance channel of these creeks. This has caused the local authority to perform regular stabilization work and maintenance dredging at great expense. Consequently, an effective long-term management plan is necessary so as to offer improved economic and environmental outcomes. To provide data for establishment of such a plan, a field measurement campaign was carried out in April-May 2011 by measuring a six-week nearshore wave regime, six weeks of tidal level measurements and two spring and two neap current recordings inside the creeks. The investigations showed the differences between these two adjacent inlets, in terms of dominant tide type, tidal prism volume and nearshore processes. Therefore, two different managerial action plans should be considered in contrast to what exist at the moment. The findings of this research will contribute to the design of alternative entrance geometry or maintenance strategies for Currumbin and Tallebudgera Creeks.