What can measuring the time for dye to travel between two manholes help determine?

Measuring the time it takes for dye to travel between two manholes provides valuable information about the velocity of water flowing in the collection system. By knowing the distance between the manholes and the time taken for the dye to reach the second manhole, the velocity can be calculated using the basic formula: velocity equals distance divided by time. This information is critical for assessing system efficiency, identifying potential blockages, and planning for capacity needs.

Understanding the velocity of flow in a wastewater system is essential for engineers and operators, as it can help in designing the system properly to prevent issues such as sedimentation and sewer overflows. The other options do not correlate with the direct measurements taken during this test; for example, the temperature of the water, the amount of wastewater present, and the level of contamination would require different methods and tools to assess.