Find out how to measure the water flows of an urban
The Site-scale Urban Water Mass Balance Assessment (SUWMBA) Tool measures the water flows into, through and out of an urban area. The tool generates a comprehensive account of all water flows in both the natural and human-made water cycles (rainfall, evapotranspiration, stormwater runoff, imported water, decentralised water, wastewater, etc.)
You can use this Excel-based tool to consider how water performance is affected by:
- built form design – e.g. building size and the perviousness of land covers
- water servicing features – e.g. rainwater tanks, wastewater recycling
- environmental conditions – e.g. rainfall and soil type.
You can use the SUWMBA Tool with the Infill Performance Evaluation Framework to better define your water sensitive project.
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Interested in applying the SUWMBA Tool?
Or email us admin@crcwsc.org.au
Where to find more information
You’ll find more information about measuring water flows on the following pages:
Useful resources
The SUWMBA Tool is simple to use
The tool performs four main steps:
- Defines the urban entity to be assessed
- Inputs parameters needed to estimate urban water flows
- Compiles the urban water mass balance
- Generates water sensitive performance indicators.
Practitioners input to the tool:
- site information (e.g. population, number of dwellings)
- environmental context (e.g. location, timeframe of analysis)
- zones within the area (e.g. land cover areas and their characteristics)
- availability of alternative water sources for particular uses (rainwater harvesting, purple pipe etc.)
- water demand (indoor and outdoor water characteristics etc.)
- hydrological model settings.
The outputs are an annual water mass balance for the assessed urban entity, and a set of 25 water sensitive performance indicators (e.g. water supply self-sufficiency, stormwater runoff coefficient, stormwater runoff naturalness ratio).
Supporting materials are available to help you
The user manual provides a step-by-step process for entering the required information into the tool.