As a result of the recent high rainfalls and subsequent flooding Melbourne Water is working with emergency services and other relevant agencies to review the impacts to our waterways and assets. 

For flood or storm emergency assistance, contact the VIC SES on 132 500 and for life threatening emergencies call 000. 

You can access current emergency information by calling the VicEmergency Hotline on 1800 226 226 or sign up to receive regular updates regarding flooding via the emergency.vic.gov.au website and app.

STORM and MUSIC tools

A model is usually needed during the design of stormwater treatments to help determine the appropriate size and design configuration, and prove that it meets minimum planning requirements.

The STORM calculator can be used to model stormwater treatments for small subdivisions, while Model for Urban Stormwater Improvement Conceptualisation (MUSIC) is used for more complex projects.

STORM calculator

The general public can use the STORM calculator to design small residential, commercial and industrial developments, ensuring they achieve the stormwater treatment objectives required by state and local government planning provisions.

It is important that the STORM calculator matches the design shown on the plans.

Access the STORM calculator

Rainwater tank mistakes

The STORM calculator assumes that rainwater tanks are used for toilet flushing, with a water use rate of 20 litres per person per day.

A common rainwater tank mistake is to enter the whole roof area into a single row in the calculator, when only part of the roof is connected to the tank. Roof parts not connected to the tank must be entered as separate rows, otherwise the calculator will assume the whole roof is connected.

Raingarden mistakes

The size of raingardens is commonly misunderstood, with household raingardens typically being one metre high in total.

The 100mm and 300mm options in STORM refer to the extended detention depth, or ponding depth above the top of gravel mulch and below the grated cap. The following diagram of a raingarden has 100mm from the top of gravel mulch to the grated cap overflow drain.

Diagram of 100mm raingarden - 100mm from top of gravel mulch to grated cap overflow drain


MUSIC is a computer model representing a project or catchment area, the drainage connections and a series of stormwater treatments. It simulates rainfall and runoff at six-minute intervals over at least one year, and then treatment by sediment basins, wetlands and other water sensitive urban design measures.

MUSIC is more sophisticated than STORM, allowing you to adjust many design dimensions and model a series of treatments, called a treatment train.

To learn more about MUSIC and how to use and purchase the tool, visit the following webpages:

Melbourne Water MUSIC guidelines (see 'Tool guidelines')

MUSIC overview - eWater

MUSIC licensing - eWater

MUSIC Auditor

MUSIC Auditor is a tool used by Melbourne Water and councils to assess MUSIC models and check they comply with Melbourne Water's MUSIC guidelines.

You can check your model before you submit it:

MUSIC Auditor


Last updated:
28 September 2017