As cities develop, more land is converted into impervious surfaces, which do not allow water to infiltrate. Careful urban planning is needed to ensure that the hydrologic cycle and water quality of the catchment areas are not affected. There are techniques that can attenuate peak flow during rain events and reduce the amount of metals, nutrients, and bacteria that enter the urban water cycle. This brief gives a short introduction on bioretention systems and documents the effectiveness of some 36 plant species in removing water pollutants. A summary on the maintenance requirements is also presented.

Angelia Sia is an Assistant Director at the Centre for Urban Greenery and Ecology, Singapore. She received her first degree from the National University of Singapore and Master of Business Administration from the Imperial College, London. In addition to managing the publishing and marketing of the award-winning periodical CITYGREEN, she looks into translating research findings into applicable outcomes through other publications, as well as streamlining processes for administrative excellence. In the course of work, she has contributed towards a number of scientific papers.

Introduction.- Selection of Plants that Demonstrated Nitrate Removal Characteristics.- Inspection and Maintenance Guidelines.