Rain drains are an important part of any drainage system. They are used to collect and divert rainwater away from buildings and other structures. The two most common types of rain drains are culverts and spouts. Culverts are large, underground pipes that allow water to flow beneath roads and other structures. Spouts are smaller, above-ground pipes that direct water away from buildings and other structures. Both culverts and spouts are essential components of a successful rain drainage system.