CHASM tool for considering re-using stormwater


Stormwater is a major untapped resource that has the potential to augment Australia’s water supply in a context of increased water demand and climate change uncertainty. Public, political and technical acceptance of stormwater reuse requires robust hazard assessment and risk management, and the majority of work to date has focused on the acute risks associated with pathogens. Chemical and micropollutant hazards in stormwater have historically been poorly understood, limiting use of this water source for beneficial reuse. 

The water industry is seeking a better method for understanding chemical hazards in alternate water sources such as stormwater: what they are, where they come from, which are most important and how to monitor for them so that the water can be used in a safe way.

The purpose of CHASM is to provide water professionals with a rapid, simple and yet robust and defensible method to 1) identify the chemical hazards associated with land use and activities in potential stormwater catchments, and 2) provide guidance on a monitoring program that would most efficiently and effectively identify chemicals of concern to ensure safe use.

Intended users of CHASM

CHASM was developed for water professionals interested in harvesting stormwater for beneficial use. The quick and easy assessment of micropollutant hazards based on land use/activities can also be used by anyone interested in assessing the micropollutant hazards of a catchment.

The latest version of CHASM is available on the Water Research Australia website. The WaterRA CHASM User Guide should be read prior to using the tool, and is also available on their website.