Evaluating design alternatives of constructed stormwater treatment wetlands

Abstract

This aims to selecting best design alternatives for constructed wetland design for treatment of stormwater runoff to prepare for the impacts of climate change in South East Queensland (SEQ). In recent years a growing public awareness of environmental issues due to climate change has been observed in Australian and the rest of the world. With an expected increase in extreme future storm events due to the impacts of climate change as observed in the 2011 flood events. Therefore it is inferred, that building better stormwater systems is crucial for preparing the region to climate change, and increase the coping capacity. In this context, in order to identify and evaluate preferred adaptation alternatives to improve South East Queensland’s (SEQ) resilience to the impacts of climate change, the authors have undertaken a multi-criteria analysis by using the AHP technique. In an exploratory study, three stakeholder groups (private sector, public sector and academic institution) were identified and consulted to determine the goal, criteria and adaptation alternatives. The combined results of this exploratory study thus far show that across the three stakeholder groups, Public Health and Safety and Flooding and Drainage Control of highest priority, respectively. When considering design alternatives the three stakeholder groups consider the extended detention wetland system to be of most importance. It was found at this stage during the sensitivity analyses that the alternative priorities did not change by any significant amount when any of the criteria priorities were altered. This suggests that data collected from the stakeholders’ is suitable for interpretation and for making recommendations. However further research and discussion including all stakeholders is required regarding adaption to SEQ.