Multiobjective Optimization of Wetlands for Attaining Flood, Water Quality and Bird Habitat Benefits

Abstract

A significant number of historically existing wetlands that naturally stored rainwater and attenuated flood peaks have now been drained and employed as new farming areas. Beyond the water quality and flow problem, this has resulted in loss of natural habitats of diverse ecological species. Restoring wetlands have hence been proposed as a potential conservation strategy to help attenuate many of these problems. In this study a spatial, multi-objective optimization study of new potential wetlands was carried out to achieve biodiversity improvements in addition to flood reduction benefits and water quality improvements. The Soil and Water Assessment Tool (SWAT) was used to simulate flow and water quality, and the USGS GAP tool was used to estimate impacts on ecological habitats. Although this study is focused on four types of bird species, as a surrogate of biodiversity across the study site (Big Creek Watershed in southwestern Indiana), the methodology can be applied to other species and regions. The study helped assess redundancies as well as trade-offs between the flooding, water quality, and habitat objective functions. Additionally, the methodology helped assess critical locations that help improve multiple goals.