Assessment of Water Quality Status Based on Water Quality Index in Zarqa River, Jordan

Abstract

Background and Objective: Water is the main component of all that exists on the surface of this earth. It is important for humans, animals, plants, and the occurrence of many biological processes. Jordan is classified as the most Arab countries that suffers from water scarcity in the region. It has limited water resources and high population growth. The Zarqa River is one of the most important rivers in Jordan. The river suffers from many environmental problems. The aim of this study is to evaluate the quality status of the water that entered the Zarqa River from as Samra wastewater treatment plant based on Water Quality Index (WQI). To evaluate the status of the river water, six water quality parameters were measured. These parameters were: DO, COD, BOD, TSS, NH3-N and ph. Materials and Method: The Malaysian Department of Environment Water Quality Index (DOE-WQI) was used to calculate and classify the water quality based on the National Water Quality Standard (NWQS), Malaysia. The data used in this study were collected by the Water Authority, Jordan in the year 2018. To achieve the aim of this study, the data were analyzed using Descriptive Statistics. Result: The calculations and classifications of the water quality parameters, the water quality of the Zarqa River was categorized under classes I to IV. The average values of DO range from 4.6 to 6.8 mg/l. The average values of COD range from 36.5 to 46.4 mg/l. The average values of BOD range from 3.7 to 4.7 mg/l. The average values of AN range from 0.9 to 1.8 mg/l. The average values of ph range from 6.97 to 7.1, and the average values of TSS range from 6.6 to 11.8 mg/l. The values of WQI for every month of the year 2018 range from 50.04 in February to 58.66 in January. Conclusion:  Based on these results and according to NWQS, the water of the Zarqa River was classified under class III. This shows moderately polluted water that needs extensive treatment.