What is a dry well and its function in drainage systems?

A dry well is defined as a structure specifically designed to facilitate the slow dispersion of water into the surrounding ground. Its primary function is to help manage excess water, typically from stormwater runoff, by allowing it to seep into the soil. This not only aids in reducing surface water accumulation but also recharges groundwater supplies, promoting better water management in drainage systems.

Dry wells are particularly effective in areas where soil conditions allow for adequate percolation, helping to mitigate flooding and erosion while also leading to a decrease in the burden on municipal stormwater systems. In contrast, the other options describe different structures or systems that do not align with the primary purpose of a dry well, such as rainwater collection, temporary water storage, or groundwater contamination prevention. Thus, the characteristic of a dry well allowing water to disperse slowly into the ground is what makes it a crucial component in effective drainage management.