Which type of building drain would not handle sewage?

A building drain that does not handle sewage is the storm drain. Storm drains are specifically designed to collect and transport rainwater or surface water runoff from precipitation, such as rain or melted snow. They are intended to manage water from the environment rather than from sanitary sources, which often contain human waste and other materials that require specialized treatment.

In contrast, combined drains, sanitary drains, and waste drains are designed to handle sewage or wastewater. Combined drains can carry both sewage and stormwater, sanitary drains are exclusively for sewage waste, and waste drains are typically used for liquid waste that may not necessarily be sewage, but still requires proper disposal and treatment. The classification of storm drains as not handling sewage is essential for maintaining the integrity of the wastewater management system and ensuring that different types of water are processed appropriately.