SPPS Strategic Planning Policy Statement Edition 2 (December 2025)·Page 62·6.114
Drainage Assessment thresholds for residential and land-use development
A Drainage Assessment is required for residential developments of 10+ units, sites over 1 hectare, change of use with new buildings/hard surfacing over 1000 m², or any development (except minor development) in areas with surface water flooding history or where runoff may adversely impact other development or conservation features.
A DA will be required for all development proposals that exceed any of the following thresholds: a residential development comprising of 10 or more dwelling units; a development site in excess of 1 hectare; or a change of use involving new buildings and/or hard surfacing exceeding 1000 square metres in area. A DA will also be required for any development proposal, except for minor development, where the proposed development is located in an area where there is evidence of a history of surface water flooding; or where surface water run-off from the development may adversely impact upon other development or features of importance to nature conservation, archaeology or the built heritage.
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