Tennessee Wastewater Operator Practice Exam

What role does algae play in aerobic and facultative ponds?

1. Removes toxic substances

2. Contributes to effluent TSS

3. Acts as a predator of bacteria

4. Decreases the need for oxygen

The correct answer is: Contributes to effluent TSS

Algae play a significant role in the functioning of aerobic and facultative ponds, particularly in their interaction with the wastewater treatment process. In these systems, algae are crucial in maintaining the balance of the ecosystem and contribute positively to the treatment process. In aerobic ponds, algae perform photosynthesis, producing oxygen during the day, which is then utilized by aerobic bacteria to decompose organic matter in the wastewater. This process helps to reduce biochemical oxygen demand (BOD) levels and promotes a healthier environment for the overall treatment process. However, while algae do provide oxygen and engage in beneficial exchanges within the lagoon, they can also contribute to total suspended solids (TSS) when they grow excessively or die off. The presence of algal biomass can increase the TSS levels in the effluent, as decaying algae can add solid materials to the water being treated. This is particularly important in evaluating the quality of effluent released from treatment facilities, as higher TSS can lead to environmental concerns and regulatory compliance issues. The role of algae is more nuanced than simply increasing suspended solids. They also improve the efficiency of the treatment processes through their interaction with bacteria. Therefore, while they contribute to effluent TSS, their overall role is integral to the effectiveness and operation