Abstract
Environmental impact assessment provides a systematic basis for identifying the beneficial and adverse consequences of development projects and formulating measures to manage those consequences. This study assessed the environmental implications of the Patuakhali Town Protection Embankment (PTPE), a flood-protection and drainage-improvement project in coastal southern Bangladesh. The study used primary data gathered from field observations, respondent surveys, focus group discussions, and key-informant interviews, together with secondary information drawn from project documents and records of relevant government institutions. Potential impacts were classified into ecological, physicochemical, and human-interest domains and evaluated using a weighted Environmental Impact Value (EIV) method. The assessment produced negative scores for the ecological domain (−45) and physicochemical domain (−100), but a positive score for the human-interest domain (+150), resulting in an overall EIV of +5. The strongest beneficial contribution was flood protection (+200), followed by compensatory plantation (+100), improved road communication (+40), and local economic development (+30). The largest adverse contributions were water stagnation (−90), waterlogging (−80), fisheries loss (−45), habitat loss (−40), vegetation loss (−40), and water pollution (−40). These results indicate that the PTPE project has a marginally positive net environmental balance because flood protection and socioeconomic benefits slightly outweigh ecological and drainage-related costs. However, this balance is conditional on regular maintenance of regulators, outlets, culverts, and internal drainage channels; effective solid-waste management; riverbank protection; preservation of aquatic connectivity; compensatory plantation; livelihood support; and enforcement against land and river encroachment. The findings suggest that the PTPE can remain environmentally acceptable only if its structural benefits are supported by continuous drainage management, environmental monitoring, and implementation of the proposed mitigation measures.
Keywords: Coastal embankment; Tidal flooding; Waterlogging; Drainage management; Mitigation measures; Weighted scoring.
