Q1: Dry water flow in a combined sewer, is

ANS:D - inclusive of domestic and industrial sewage but excludes storm water.

"Inclusive of domestic and industrial sewage but excludes stormwater" refers to the composition of dry water flow in a combined sewer system. Here's a breakdown:

1. Domestic Sewage: This includes wastewater generated from households, such as water from sinks, toilets, showers, and laundry. Domestic sewage contains organic matter, nutrients, and various contaminants typically found in residential wastewater.
2. Industrial Sewage: Industrial sewage comprises wastewater discharged from industrial processes and commercial establishments. It can contain a wide range of pollutants depending on the industry, including chemicals, heavy metals, oils, and other substances used or produced during manufacturing processes.
3. Exclusion of Stormwater: Stormwater refers to precipitation runoff from rain or melted snow that flows over surfaces and collects pollutants as it travels. In combined sewer systems, stormwater enters the same pipes as domestic and industrial sewage during wet weather events. However, during dry weather periods when there is no rainfall or runoff, stormwater is absent from the flow in the combined sewer.

Therefore, "inclusive of domestic and industrial sewage but excludes stormwater" means that the dry water flow in the combined sewer system consists of wastewater from households and industries but does not include runoff from precipitation events. This dry weather flow represents the normal flow of wastewater during dry periods and is managed and treated accordingly within the combined sewer system. It's worth noting that managing stormwater separately from sanitary sewage and industrial wastewater helps prevent overflows and reduces the risk of pollution in receiving water bodies during heavy rainfall or snowmelt events.