Evaluating the Capability of Grass Swale for the Rainfall Runoff Reduction from an Urban Parking Lot, Seoul, Korea.

Muhammad Shafique,Kwon Kyung-Ho,Reeho Kim

doi:10.3390/ijerph15030537

Abstract

This field study elaborates the role of grass swale in the management of stormwater in an urban parking lot. Grass swale was constructed by using different vegetations and local soil media in the parking lot of Mapu-gu Seoul, Korea. In this study, rainfall runoff was first retained in soil and the vegetation layers of the grass swale, and then infiltrated rainwater was collected with the help of underground perforated pipe, and passed to an underground storage trench. In this way, grass swale detained a large amount of rainwater for a longer period of time and delayed peak discharge. In this field study, various real storm events were monitored and the research results were analyzed to evaluate the performance of grass swale for managing rainfall runoff in an urban area. From the analysis of field experiments, grass swale showed the significant rainfall runoff retention in different rain events. Grass swale markedly reduced total rainfall runoff volume and peak flow during the small storm events of intensity about 30 mm/h. From the analysis, on average rainfall runoff retention from the grass swale was found around 40 to 75% during the various small rain events. From the results, we can say that grass swale is a stormwater mitigation practice which can help avoid flash flooding problems in urban areas.

Highlights

For the last few decades, rapid urbanization is the main cause of surface water deterioration around the globe [1,2]
To encounter these adverse urban water-related problems associated with urban development, Low Impact Development (LID) practices have been applied in different countries and shown multiple benefits for stormwater management in urban areas [4,5,6,7,8,9,10]
Infiltration practices are designed to contribute to urban drainage by retaining a large amount of rainfall runoff and reducing the flow volume and peak flow which reduces the chances of flash flooding in urban areas

Summary

Introduction

For the last few decades, rapid urbanization is the main cause of surface water deterioration around the globe [1,2]. As a result of this more runoff is collected on the surface, which causes flash flooding and water quality degradation problems [2,3,4,5,6,7] To encounter these adverse urban water-related problems associated with urban development, Low Impact Development (LID) practices have been applied in different countries and shown multiple benefits for stormwater management in urban areas [4,5,6,7,8,9,10]. Infiltration practices are designed to contribute to urban drainage by retaining a large amount of rainfall runoff and reducing the flow volume and peak flow which reduces the chances of flash flooding in urban areas

Objectives

Methods

Findings

Discussion

Conclusion