Potential of Stormwater Source Control Measures for Urban Development: A review for a High-Density Area

The sustainability of conventional stormwater management systems has long been considered impractical. However, many cities around the world still use combined sewers to deal with both waste and stormwater. As those cities continue to grow and their population densities increase, combined sewer overflows (CSOs) may cause adverse effects on receiving waters.

Sanitation infrastructure and stormwater management in urbanized areas have made different advances in recent decades. A wide range of source control measures have been gradually implemented in new developments and redevelopment to reduce contaminants and the rate and volume of water runoff through increasing infiltration or storage, and thus reducing the impact of stormwater loads entering the sewers. However, the implementation of these practices in older and higher-density metropolitan areas is still limited.

In Bangkok, the implementation of sewerage systems to service the whole population has become the main water quality objective over the last few decades. Pollutants generated from anthropogenic activities are often washed out to downstream catchments and water bodies during storm events. Domestic sewage is considered as a significant source of organic and nitrogenous pollution in Bangkok (Buathong et al., 2013; ADB, 2012). The implementation of open stormwater systems may provide an ability to reduce CSOs and handle runoff volumes locally.

The aim of this study was to review the potential of source control measures to reduce stormwater pollution and lower stormwater runoff in a high-density area by drawing from peer-reviewed articles on the various practices. An overview of source control techniques and key research findings highlighted the potential of green roofs, bioretention devices, permeable pavements, swales, detention ponds, and constructed wetlands. Finally, the results of their potential were synthesized and parallels were drawnwith areas in Bangkok where environmental quality improvement might be promoted.