MUSIC v6 and WSUD
Designing urban development proposals that meet Water Sensitive Urban Design Standards has been made easier with the release of the new version of the urban stormwater software, MUSIC v6.
From governments to catchment management groups, many organisations have introduced initiatives to protect the aquatic environment of urban areas. While the initial focus was on point sources of pollution, such as sewage discharge and industrial effluent, attention has now turned to diffuse sources of pollution, such as urban stormwater. Indeed, stormwater runoff is recognised as a major carrier of urban pollutants.
It is difficult to prevent stormwater from damaging and polluting creeks because runoff can be contaminated almost anywhere rain falls, and excessive flows will occur wherever there are impervious surfaces directly connected to waterways. Consequently, successful initiatives to manage stormwater must adopt a catchment-wide approach, with a particular focus on tackling the sources of stormwater runoff at or near their source. The diffuse sources of stormwater pollution also demand a multi-disciplinary approach. Successful initiatives may need to integrate a range of urban planning and design disciplines, including urban hydrology, land-use planning, landscape design and asset life-cycle economics.
MUSIC can model a wide range of treatment devices to find the best way to capture and resuse stormwater runoff, remove its contaminants, and reduce the frequency of runoff. MUSIC helps you to evaluate these treatment devices until the best combination of cost, hydrology and water quality improvement is achieved.
These are vegetated stormwater filtration systems that use a soil or sand-based filtration medium to remove particulates and soluble contaminants. The system may be lined or unlined and may or may not have an underdrain. In MUSIC v4, based on significant extra data and research, bioretention nodes take better account of the characteristics of the filter media and vegetation. MUSIC users can now more accurately design or represent a variety of different bioretention systems.
Unvegetated infiltration systems, for removing contaminants, which have no underdrain. MUSIC v4 offers a greatly enhanced infiltration modelling capacity to account for horizontal flows from storage and allow for changes in flow with depth. There is greater flexibility to model systems with lined sides or base.
Media filtration systems
Unvegetated stormwater filtration systems for removing contaminants, using media such as gravel, sand or other fine granular material. They are assumed always to have an outlet pipe (underdrain). MUSIC v4 was the first MUSIC version to include this as a treatment node.
Gross pollutant traps
These mesh-like devices are designed to remove floating and suspended rubbish and debris above 5mm in size. Many are proprietary off-the-shelf items.
Strips of vegetated land beside a road are effective in the removal of coarse and medium-size suspended particles; they provide good pre-treatment prior to a bioretention system or other vegetated treatment measures.
Open channels that use vegetation to primarily remove suspended solids. Subject to high flows, they rely on shallow slopes and the density and height of vegetation, to work well.
Ponds and sedimentation basins
Open water bodies act as temporary stores to allow the settling of suspended solids. They can include ornamental ponds, but usually lack vegetation. Reuse of the water is an option.
These domestic water stores enable roof runoff to be captured and used. Contaminants can either settle in the tank or are removed when the water is used on a garden. Tanks can reduce stormwater flows and help to counteract the increase in impervious area that urbanisation brings. They also provide an alternative water supply.
These are heavily vegetated water bodies; the physical, chemical and biological processes that they facilitate remove fine suspended sediment and soluble and insoluble contaminants. Wetlands are commonly used as ‘end of pipe’ measures, but recent research shows they also work well earlier on. MUSIC can also model reuse of the water in a wetland’s permanent pool.
Assists in stormwater peak flow management. New in version 5.
Generic treatment nodes
MUSIC allows the user to model a treatment device that is not a specific node within the program, if the user has sufficient data to model it effectively; for example, flow diversions, flow dilutions or contamination by sewer overflow. In these cases, MUSIC allows the user to define ‘transfer functions’ for flows and water quality.
Development of MUSIC
MUSIC – Model for Urban Stormwater Improvement Conceptualisation – was first developed in 2001.
Research by Dr Tony Wong and colleagues at Monash University and eWater’s forerunner organisation, the CRC for Catchment Hydrology identified that urban water professionals needed a decision support system to evaluate treatment measures and strategies if urban stormwater quality was to be improved.
Fundamental to this was research that showed that treatment of nearly all urban stormwater systems could be simulated using one model, the ‘universal stormwater treatment model’. This breakthrough, combined with a detailed understanding of the hydrology and pollutants of urban areas, gave Dr Wong’s team the necessary building blocks that became MUSIC.
The MUSIC development team focused on having a tool that, though easy to use, was underlain by high quality science. Dr Wong recognised that the science of estimating water quality had tended to become event-based and deterministic, whereas the quality of urban stormwater really depends on the statistical outcome of many rainfall events interacting with a handful of physical and chemical processes. If this ‘actuarial approach’ could be captured with an appropriate algorithm, calculations would be much simplified.
The hydrology inside MUSIC, developed by Francis Chiew and colleagues in the CRC for Catchment Hydrology, is based on defining an impervious area and the properties of related pervious areas. Once this is done, the runoff from an area can be estimated. More and more, confident estimates of hydrology are becoming as important as estimating water quality. In fact, changes in urban hydrology can have major impacts on the health of creeks and streams, as work by Associate Professor Tim Fletcher (a member of the MUSIC development team) and colleagues at Monash University has shown.
MUSIC is supported by eWater and is strongly grounded in proven Australian science and user experience to reduce the uncertainty surrounding stormwater management strategies.
- Version 2 extended the features and provided export options
- Version 3 introduced life-cycle costing, rainwater tanks and infiltration basins
- Version 4 provided more powerful modelling of bioretention and inflitation systems, as well as simpler calibration tools and improved support.
- MUSIC version 5 offered significant new capabilities, including the ability to: model additional pollutants; assess development submissions; understand peak flow impacts, the effects of storage and detention treatments and the water balance; simulate rainwater and stormwater harvesting options and import and export to other models. With MUSIC version 5 also featured an enhanced user interface and improved capacity to report and chart results.
Since MUSIC was first developed in 2001, the software has been used by thousands of professionals working in private practice and in state, regional and local government agencies throughout Australia.
With rigorous testing by hundreds of users, the feedback we have received about MUSIC has been used to expand its capabilties and make it more robust and reliable.