Assessment of pluvial flood events based on monitoring and modeling of an old urban storm drainage in the city center of Yangon, Myanmar

Abstract

Pluvial flooding is a critical issue in cities worldwide, particularly in lowland areas with old and deteriorating drainage systems. The primary driver of pluvial flooding is extreme rainfall; other drivers include urbanization, inadequate drainage system, improper solid-waste management, and tidal backwater effect. However, the interplay between these drivers makes predicting pluvial floods difficult and complex. Previous studies in developing countries seldom used water-level data or simulation modeling to identify the causes of pluvial flooding. In this study, rainfall data and water-level variations in an open channel drain and a receiving river controlled by sluice gates were collected and evaluated in detail to investigate pluvial flooding events. To predict these events, we generated a hydrodynamic model using InfoWorks ICM and verified its results using water logger data and official field reports. Analysis shows that drainage-system failures due to solid blockage and receiving water-level variation contribute more to pluvial flood occurrence than heavy rainfall. Lastly, we discuss measures to mitigate pluvial flooding in Yangon, Myanmar. The proposed monitoring and modeling approach can suitably predict pluvial flooding occurrence and provide useful quantitative data for flood risk management.

Investigation of Decentralized Wastewater Treatment System in Urban Wastewater Management: Case Study in Yangon, Myanmar

“…The urban area has 1.1 million household units, with a noteworthy 84.84% of households having access to improved sanitation facilities, as reported by YCDC. Among them, only 3% of households use pit latrines, while 80% have septic tanks [37]. The Yangon centralized wastewater treatment system in Botahtaung, located at 16.767278, 96.190167, was selected as the CWTS case study.…”