In 2007, the Stormwater Management Authority (SMA) was created under the Local Government (Stormwater Management) Amendment Act 2007, based on the Stormwater Management Agreement between the State Government and the Local Government Association. Under the Agreement, functions of the SMA include the facilitation and coordination of stormwater management planning by councils involving production of stormwater SMPs.

Current legislation concerning stormwater management and powers and responsibilities of various parties is contained in the Local Government (Stormwater Management Agreement) Amendment Act 2016 (Schedule 1A of the Local Government Act 1999) and the Natural Resources Management Act 2004.


A number of catchment-wide flood mitigation studies have been undertaken in recent decades including a study commissioned in 2003 by the then Patawalonga Catchment Water Management Board that resulted in the 2006 Master Plan report. Current project, attempts to finalise a flood mitigation plan had been unsuccessful.

As a result of the 2007 legislation, the five catchment councils assumed responsibility for implementing the 2006 Master Plan, thereby establishing the Brown Hill Keswick Creek Stormwater Project.

In February 2008, the SMA conditionally approved the 2006 Master Plan as the Stormwater Management Plan (SMP) for the catchment, however due to subsequent concerns about aspects of the Plan, the five catchment councils and SMA agreed, in 2009, to prepare a revised SMP.

The revised SMP would comply with the Stormwater Management Planning Guidelines of the SMA, introduced in 2007, including consideration of broader stormwater management initiatives, and in particular, stormwater harvesting and reuse.

Over subsequent years, extensive whole of catchment community consultation was undertaken on proposed flood mitigation measures to inform the development of the revised SMP.

In February 2017, the current SMP (“2016 SMP“) was approved and gazetted, which includes the construction of $140 million of flood mitigation infrastructure works along major watercourses of the catchment.

It is estimated that a one in 100-year flood would affect over 2,000 properties across the catchment and cause damages of about $122 million. Crucially, the SMP works are designed to mitigate the effects of such a flood to less than $1 million of damages on fewer than 100 properties.

Significantly, there are also other major benefits of the planned flood mitigation works, including creek rehabilitation, associated creek water quality and biodiversity improvements, as well as enhanced recreational amenity in open space areas traversed by watercourses. Works are also planned for improved quality of stormwater runoff and reduced impact on receiving waters.


The following extensive community consultation was undertaken in preparation of the SMP:

Whole of catchment community consultation was undertaken in November and December 2011, which included an information mail-out to over 20,000 addresses in the catchment community, and public open days at Mitcham, Unley and West Torrens Council centres.

Another community consultation program was carried out in June 2014 to address flood mitigation options for Brown Hill Creek in Orphanage Park, Unley.

More wide-scale community consultation followed in May and June 2015 on proposed flood mitigation measures for upper Brown Hill Creek. This consultation process included open days for the general community and meetings for creek owners to learn more about proposed works and provide feedback to project staff.

The outcomes of this community consultation process were reported to the five catchment councils who, in September 2015, unanimously agreed on a ‘creek capacity upgrade’ option, enabling the project’s SMP to be finalised for the SMA’s approval.

The following information for the community was provided at the time, with some of this information now superseded by more up to date information.


Current relevant reports and investigations can be accessed throughout this website under corresponding project information. For other publicly available reports and information which have been superseded and archived, please click here.