CWEA Grade 4 Practice Test 2026 - Free CWEA Grade 4 Practice Questions and Study Guide

The correct answer emphasizes the range of detrimental effects industrial wastewater discharges can have on wastewater collection systems. When industrial wastewater is introduced into the sewer system, it often contains high concentrations of chemicals and other substances that can corrode plumbing infrastructure. This corrosion can weaken pipes, leading to leaks and structural failures over time.

Additionally, industrial discharges may contribute to blockages within the sewer lines, as certain materials can solidify or react within the system, causing plugs that restrict or halt the flow of wastewater. Moreover, the presence of organic material and various chemicals can lead to the production of foul odors and the release of toxic gases, such as hydrogen sulfide, which poses health risks to workers and nearby communities.

These combined factors illustrate a comprehensive understanding of how industrial wastewater can adversely affect sewage systems, making the choice that identifies corrosion, blockage, odor production, and toxic gas release the most accurate in describing the negative impacts of these discharges.