Reducing Flood Risk in Changing Environments: Optimal Location and Sizing of Stormwater Tanks Considering Climate Change

Abstract

In recent years, there has been an increase in the frequency of urban floods as a result of three determinant factors: the reduction in systems’ capacity due to aging, a changing environment that has resulted in alterations in the hydrological cycle, and the reduction of the permeability of watersheds due to urban growth. Due to this, a question that every urban area must answer is: Are we ready to face these new challenges? The renovation of all the pipes that compose the drainage system is not a feasible solution, and, therefore, the use of new solutions is an increasing trend, leading to a new operational paradigm where water is stored in the system and released at a controlled rate. Hence, technologies, such as stormwater tanks, are being implemented in different cities. This research sought to understand how Climate Change would affect future precipitation, and based on the results, applied two different approaches to determine the optimal location and sizing of storage units, through the application of the Simulated Annealing and Pseudo-Genetic Algorithms. In this process, a strong component of computational modeling was applied in order to allow the optimization algorithms to efficiently reach near-optimal solutions. These approaches were tested in two stormwater networks at Bogotá, Colombia, considering three different rainfall scenarios.

A Framework for Calculating Peak Discharge and Flood Inundation in Ungauged Urban Watersheds Using Remotely Sensed Precipitation Data: A Case Study in Freetown, Sierra Leone

“…For example, for the Congo Valley River baseline LULC scenario, the two year storm affected 1630 people while the 100 year affected 2270 people. This points out that larger storm events cause more flood impacts and need to be mitigated in the future, especially as climate change causes more frequent and larger precipitation events [8,9,91]. Additionally, the largest increases in affected population from the baseline to BAU scenario typically occur for smaller return period storms.…”

“…Additionally, urbanization along river channels without regard for the floodplain impacts the hydraulics of the river and puts infrastructure at significant risk of being flooded [6,7]. Increased risk of hazardous flooding causes negative impacts to the economy, existing infrastructure, public health, and loss of life [6][7][8][9][10]. The effects of the economic upheaval associated with flooding are typically centered in low-to-middle income cities and countries without the necessary infrastructure to prevent or combat significant impacts of flooding [11].…”

Decline in Environmental Quality and Spatial Dynamics of New City Area Development Metropolitan Mamminasata, South Sulawesi, Indonesia

“…This figure confirms that the domestic waste produced is not managed optimally and that environmental sanitation has not been fulfilled is one of the factors that causes environmental pollution in the new city area of Moncongloe-Pattalassang. This means that waste management and poor sanitation are factors that cause various environmental and social impacts and affect public health [70].…”

Inclusion of Hydraulic Controls in Rehabilitation Models of Drainage Networks to Control Floods

“…Better results are obtained by the combination of STs and the replacement of pipes with others with higher diameters. Saldarriaga et al [17] applied two different approaches to determine the optimal location and size of the storage units through the application of Simulated Annealing and Genetic Algorithms. This research validated the use of STs for peak flow reduction in urban areas.…”