An Assessment of Physicochemical Properties and Microbial Count in Dairy Wastewater in Savar Area, Bangladesh

The dairy sector in Bangladesh releases huge amounts of wastewater in the open environment. Dairy wastewater is enriched with hazardous contaminants, which can cause various health complications. The objective of this study was to evaluate the water quality of dairy wastewater by determining the physicochemical properties of tap water and wastewater from three farms from the Islamnagar zone, Savar, Dhaka, and also to assess the significant impacts of wastewater on the environment. The most important physicochemical properties investigated include pH, total dissolved solids (TDS), electrical conductivity (EC), dissolved oxygen (DO), and microbial colony count. The results revealed that in tap water, the pH ranged from 7.11 to 7.20, and in wastewater, it ranged from 7.30 to 7.77. The TDS in tap water ranged from 109 to 116 mg/L, and in wastewater, it ranged from 451 to 2000 mg/L. The EC values were found in tap water from 0.22 to 0.23 mS/cm, whereas in wastewater, they ranged from 0.86 to 13.20 mS/cm. Additionally, for DO, the tap water ranged from 4.21 to 6.25 mg/L; in wastewater, it ranged from 0.98 to 1.86 mg/L. The pH and TDS stayed within the standard limits in the physical–chemical parameters assessed. However, the EC and DO are not within the DoE (Department of Environment, Bangladesh)-allowed limits. In addition, more microbial colonies have occurred in wastewater than in tap water. The study demonstrates that the discharge of dairy wastewater in the open field is detrimental to our ecosystem, and a proper treatment facility is essential.