Texas Wastewater Class B Practice Exam

What method is best for determining whether a storm drain is connected to a sanitary sewer line?

1. Water pressure testing

2. Smoke test

3. Visual inspection

4. Camera inspection

The correct answer is: Smoke test

The best method for determining whether a storm drain is connected to a sanitary sewer line is the smoke test. This method involves introducing a non-toxic smoke into the sewer system and observing where it escapes. If the storm drain is connected to the sanitary sewer, the smoke will come out of the storm drain, indicating a potential cross-connection. Using a smoke test is effective because it directly reveals unintended connections in a clear and visual manner. It can easily show leaks and connections that might not be visible through other means. Additionally, this method is relatively quick and can cover a large area, making it efficient for identifying problematic connections. Other methods, while useful in their own contexts, may not provide the same level of clarity. For instance, water pressure testing is generally used to assess the integrity of sewer lines but may not specifically indicate connections to storm drains. Visual inspection could miss underground connections or problems that are not immediately apparent, and camera inspection, while effective for observing the interior of sewer lines, could be limited in detecting external connections without additional diagnostic support such as smoke testing.