What is the main function of a dry well in landscape design?

The main function of a dry well in landscape design is to catch runoff directly from a roof drain. A dry well is an underground structure designed to manage excess stormwater by collecting and temporarily storing it. When rainwater from a roof drains into the dry well, it allows the water to percolate slowly into the surrounding soil, reducing the risk of erosion and surface flooding. This function is particularly important in areas where stormwater management is needed to comply with environmental regulations or to mitigate flooding in urban settings.

In this context, while retaining water can be a feature of some systems, a dry well is primarily focused on handling runoff from impervious surfaces like roofs, ensuring efficient drainage and facilitating groundwater recharge. This distinguishes it from other options that may imply a different primary purpose or function.