SPPS Strategic Planning Policy Statement Edition 2 (December 2025)·Page 63·6.124
Artificial modification of watercourses - environmental impacts
Culverting and canalisation of watercourses can increase downstream flood risk and cause environmental damage including impacts on landscape, ecology and biodiversity, making such modifications environmentally unsustainable.
While culverting may in some instances alleviate local flood risk, it cannot eliminate it and often increases the flood risk downstream by the accumulation of higher flows. The artificial modification of watercourses through culverting or canalisation is also widely considered to be environmentally unsustainable as such operations can adversely impact upon landscape quality, ecological integrity and biodiversity of watercourses.
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