A framework of water quality management to maintain sustainability and simplify EIA

Abstract

A framework of water quality management is proposed in this study to maintain the sustainability of watershed and simplify project environmental impact assessment (EIA). Continuously mining natural resources and discharging pollutant to environment result in degradation of water quality in Taiwan. Although EIA is required for new developing projects, stream still keeps degrading due to lack of considering cumulative impacts. To maintain sustainability, cumulative impacts should not exceed environmental carrying capacity. In this study, carrying capacity is evaluated and allocated to land units, and thus cumulated pollutant discharge from all land units will not exceed carrying capacity. Then, a developing project only needs to check whether it meets the requirement that designed pollutant discharge divided by developing area does not exceed unit pollutant load. A case study has been done for the TouChien Creek watershed, which carrying capacity of BOD is estimated by QUAL2E and allocated by an optimization model, respectively. The proposed framework not only simplifies the process of EIA but also guarantees that cumulative impacts will not exceed carrying capacity to maintain sustainability.