Wastewater strength is primarily expressed in terms of which of the following?

Wastewater strength is primarily expressed in terms of suspended solids, biochemical oxygen demand (BOD), and chemical oxygen demand (COD) because these measures provide critical insights into the organic and inorganic matter present in the wastewater.

Suspended solids indicate the amount of particulate material in the water, which impacts both treatment processes and environmental discharge standards. BOD measures the amount of oxygen that microorganisms will consume while decomposing organic matter, which serves as an indicator of the potential impact on receiving waters. COD quantifies the total oxygen demand required to chemically oxidize organic and inorganic substances, offering a more comprehensive view of the water’s overall pollution strength than BOD alone.

Other considerations like pH and temperature, while important for the biological processes in treatment systems, do not serve as direct measures of strength. Nutrient levels are significant for assessing potential eutrophication but are not typically categorized under wastewater strength. Volume and flow rate relate to the quantity of wastewater but do not directly indicate its concentration of pollutants or strength. Therefore, the combination of suspended solids, BOD, and COD provides a robust framework for evaluating wastewater strength and guiding treatment processes effectively.