Optimal LID Considering Cost and Effectiveness

Rapid urbanization increases rainfall runoff and the discharge of non-point source pollutants. These outflows and pollutants have mainly been reduced through detention in reservoirs, diversion to sewage treatment plants, or the use of non-point pollution reduction devices before entering rivers. However, in recent years, efforts have focused on reducing them at the source. Representative concepts for this approach are Low Impact Development (LID) and Green Infrastructure (GI). Facilities for this include Porous Asphalt Pavement (PA), Porous Asphalt Pavement (PB), Infiltration Trench (IT), and Tree Box Filter (TB), and various other forms have been proposed, such as rooftop greening and storage-type green spaces. These facilities can be applied to existing cities or new development sites, but they can be implemented more efficiently in newly developed sites. In this study, an optimization search was conducted to achieve maximum reduction effect and minimum cost by selecting optimal LID facilities using the Harmony Search (HS) algorithm for new complexes. As a result of the analysis, it was possible to select the type, size, and location of facility appropriate for optimal efficiency and cost. According to the technique presented in this study, it is expected to be useful in practice, as it allows the selection of optimal solutions for very complex and diverse conditions.