Site selection of sustainable urban drainage systems using fuzzy logic and multi-criteria decision-making

The rapid growth of cities together with increases in their populations is accompanied by numerous problems in run-off management when flood events occur. The LID-BMP (Low Impact Development-Best Management Practice) approach seeks an environment-friendly development in the management of surface run-off. One important aspect of using such systems is to determine the optimal placement for effective storm water management. The current research presents a method for finding optimum locations for LID-BMP systems. The study area is located in the northern region of Tehran, the capital city of Iran. Three systems, infiltration trenches, vegetated swale and bioretention, were selected for this study. At first, criteria effective in finding locations for these systems were identified, comprising slope, land use and distance from streams, roads, groundwater and fault lines. Then, fuzzy logic and the analytic hierarchical process in Geographic Information Systems (GIS) were employed to combine multiple layers to select optimum locations for these three systems. Finally, considering the field study and taking into account the specific land uses in the region, the optimum locations for these systems were suggested. The sensitivity analysis results showed that the suitable sites were intensely affected by the land use criterion; therefore, attention is recommended, especially in developed urban areas.