Author(s): Sri Puji Saraswati, Sunjoto, B. Agus Kironoto, Suwarno Hadisusanto
Linked Author(s): Sri Puji Saraswati
Keywords: Water resources management & conservation, Water Quality Index (WQI), EPT diversity index, AODs toxicity test
Abstract: Water Quality Index (WQI) is an important tool in river management. WQI based on conventional water quality parameterization often emphasizes more on anthropocentric views. Water quality analysis using ex-situ and in-situ biomonitoring is considered more objective, more comprehensive representation of the river health status and better approach for river water quality conservation than conventional approach. However, biomonitoring is considered as complicated by engineers and practitioners in water management. Many researchers and practitioners in Indonesia usually use the existing WQI developed in other countries. Three of the most commonly used WQIs are: Storet, Pollution Index and INWQS. The first two are developed in the USA, while INWQS is developed in Malaysia. This research attempts to investigate whether those WQIs developed in countries with different climate and environmental condition are suitable to be used directly in Indonesia. Water quality parameters used as a reference in this study is the biological criteria using ex-situ biomonitoring i. e. AODs (Aquatic Organism environmental Diagnostic) toxicity test using fish and shrimp indicators and in-situ biomonitoring based on EPT (Ephemeroptera, Plecoptera and Trichoptera) diversity index. Water quality parameters are monitored at 5 locations along Gadjah Wong stream, Yogyakarta over 2 year's period covering pH, TSS, DO, BOD5, COD, NH3. Since Water Qualilty Conservation Standard has not yet been established, water quality as required for level-I water usage in Yogyakarta Governor Regulation is used as the water quality target. Based on this study, WQI results from the three methods are inconsistent with the ex-situ and in-situ biomonitoring results. From the literature review and current study, the three methods are not always applicable in determining the river health status. Tropical climate as well as specific hydrogeobiochemical characteristics of Indonesia necessitate the development of a specific method for WQI determination
Year: 2017