Taste and odor problems in finished water are primarily traced to algae in what location?

• A. In the stream or impoundment above the intake
• B. In the groundwater
• C. In the distribution system
• D. In the treatment plant

Answer: (B)

Taste and odor problems in finished water come mainly from compounds produced by algae in the source water. When algae bloom in a stream or in the impoundment (reservoir) upstream of the intake, they release earthy or musty compounds such as geosmin and MIB that can persist through treatment and appear in the final water. Groundwater generally lacks these algal processes, so it’s not the typical source of taste and odor issues. Issues in the distribution system or at the treatment plant can affect how these tastes and odors are perceived, but the root cause is upstream in the stream or reservoir above the intake.