4 - Biochar for sustainable drainage system

Abstract

Sustainable urban water management requires a paradigm shift from using conventional system to drain storm water as waste to using innovative storm water management technique to harvest and reuse the water. Sustainable drainage systems (SuDS) are designed to achieve the goal. Although SuDS have been used for almost two decades, the implementation has been predominantly in temperate region. The implantation of SuDS results in a variation in water quantity and quality controls in tropical and subtropical regions, which receive more intensive and frequent rainfall events than the temperate regions. To improve the reliability of SuDS, the utilization of amendments derived from waste materials such as biochar has a potential to reduce waste disposal at landfill while improving the quality of storm water discharge. Continuous monitoring and predesign modeling are necessary to deliver effective design guidelines based on the rainfall-runoff profiles. Innovative design measures including modification of filter media by biochar and selection of vegetation are suggested to enhance storm water treatment and minimize seasonal effects such as intensive flow and distinct wet/dry periods in subtropical climates. In this chapter, we discussed the critical design factors to achieve successful SuDS, the role of biochar in SuDS, and the application biochar in SuDS. At the end, challenges and opportunity to further improvement of SuDS design guidelines are listed.